MediaLab that I'm wrong

Unless an alternative has been approved by the FDA, what is the expiration and storage temperature of rejuvenated (non-frozen) RBC's? A) 24 hours; 1 °C to 6 °C B) 48 hours; 1 °C to 10 °C C) 72 hours; 1 °C to 6 °C D) 24 hours; Room temperature

A) 24 hours; 1 °C to 6 °C

An increased serum level of which of the following analytes is MOST commonly associated with decreased glomerular filtration? A) Creatinine B) Uric acid C) Urea D) Ammonia

A) Creatinine Plasma concentrations of creatinine are used to assess renal function. Creatinine clearance is based on the serum creatinine level and is used to measure glomerular filtration rate or GFR.

The object shown at the arrow in this image was found in a formed stool and measured 15 µm. What is the identification and stage of this organism? A) Entamoeba histolytica cyst B) Entamoeba hartmanni cyst C) Entamoeba coli cyst D) Endolimax nana cyst

A) Entamoeba histolytica cyst 🔬 Entamoeba histolytica cysts: 10-20 µm 😲 2-4 nuclei 👀 small central karyosome surrounded by evenly distributed peripheral chromatin thin chromatin bars in older cysts 😯 🔬 Entamoeba hartmanni cysts: 6-8 µm 4 nuclei in mature cysts, usually 2 nuclei 🔬 Entamoeba coli cysts: 15-25 µm 📏 8 nuclei, sometimes 16+ 😮 Coarse granular peripheral chromatin unevenly distributed on the membrane 🔬 Endolimax nana cysts: 6-8 µm, usually oval 4 nuclei in mature cysts, no peripheral chromatin 🚫

This Xylose Lysine Decarboxylase (XLD) medium shown in this photograph was isolated from a stool specimen of an immunocompetent adult. Your best action would be to: A. Report it as no Salmonella or Shigella isolated B. Work it up for possible Salmonella spp. C. Work it up for possible Yersinia enterocolitica D. Serotype it for Escherichia coli O157:H7

A. Report it as no Salmonella or Shigella isolated XLD Media Snapshot 📸 Lactose, xylose, and/or sucrose fermenter: Picture-perfect in red! Salmonella and Shigella: Red on XLD, with Salmonella rocking black centers (H2S production). 🌈 Bonus Features: Yersinia enterocolitica and E. coli O157:H7: Shine in yellow on XLD, but prefer CIN and Sorbitol MacConkey media for a VIP treatment. 🔍 Pro Tip: XLD's exclusive guest list includes Salmonella and Shigella. 🚫 Others, head to CIN and Sorbitol MacConkey for the ultimate party! 🎉 #MicrobiologyMagic #MediaMatters

The following BEST describes serum hCG levels during pregnancy: A. Rise in levels throughout pregnancy B. Highest levels found at the end of pregnancy C. The rapid rise in levels during the first trimester; slow decline and possible level-off throughout the remainder of the pregnancy D. The slow rise in levels during the first trimester; rapid rise during the second trimester; slow decline during the third trimester

C. The rapid rise in levels during the first trimester; slow decline and possible level-off throughout the remainder of the pregnancy hCG goes up fast in early pregnancy, starts dropping around week 16. Slowly decreases and can stabilize for the rest of the pregnancy. 📈👶

What is the most frequent genotype among Rho (D) negative persons? A. r'r B. r'r" C. rr D. r"r

C. rr

What is the half-life of digoxin in plasma? A) 8 hours B) 18 hours C) 28 hours D) 38 hours

D) 38 hours

Which of the following blood groups reacts least strongly with anti-H? A) O B) A2 C) A1 D) A1B

D) A1B Blood groups have different amounts of H antigen on red cells: 🅾️ > 🅰️2 > 🅱️ > 🅰️2🅱️ > 🅰️1 > 🅰️1🅱️. So, 🅰️1🅱️ has the least H antigen, making its reaction with anti-H the weakest.

Observation of colonies producing brick red fluorescence under long-wave ultraviolet light on KVLB agar allows for presumptive identification of which anaerobic bacterial genus? A. Fusobacterium B. Peptostreptococcus C. Bacteroides D. Prevotella

D. Prevotella 🔬 Anaerobic bacteria listed: Prevotella: KVLB (kanamycin and vancomycin) growth, may produce brick red fluorescence under UV light (🔦 Wood's lamp). Fusobacterium species (except F. nucleatum): KVLB growth, chartreuse fluorescence. Peptostreptococcus: ❌ KVLB growth, no fluorescence, susceptible to SPS (sodium polyanethol sulfonate). Bacteroides: KVLB and BBE agar growth, no fluorescence. 🔬🔍

What do the majority of centrifuge accidents stem from? A. Centrifuge brand or type B. Voltage or power source used C. Setting of time and speed of centrifuge D. User error

D. User error OSHA reports that most centrifuge accidents result from user errors. 🚨🔍 Proper training is crucial, including checks for tube cracks, clean spindles, avoiding overfilling, and regular maintenance. ⚠️🔄 Brand/type and power source aren't major causes. Users should follow guidelines and manuals for setting time and speed. 📚⚙️ This doesn't contribute significantly to accidents. 🚫‍🔬

In heme synthesis, how many molecules of delta-aminolevulinic acid (ALA) are needed to form one molecule of heme? A) 2 B) 4 C) 6 D) 8

The correct answer is 8 molecules of ALA are needed to form 1 molecule of hemoglobin.

What is the required storage temperature for thawed cryoprecipitate? A. 4 - 8 ºC. B. 20 - 24 ºC. C. 35 - 37 ºC. D. -20 ºC or colder

B. 20 - 24 ºC. Once liberated from the icy embrace, cryoprecipitate craves the spotlight at room temperature (20 - 24°C) for a grand 6-hour performance. 🌡️❄️ If it's mingling in an open system pool, the countdown shortens to 4 hours, still sizzling at 20 - 24°C. 🕰️🎉 All other temperatures? They're the VIP section rejects, too cool or too hot for this cryo party! ❄️🎊

How soon must granulocyte concentrates be administered after donation? A. 12 hours B. 24 hours C. 3 days D. 30 days

B. 24 hours Granulocytes go bad quickly! 🕰️ Transfuse ASAP, always within 24 hours! ⏰ Use only if patient = low neutrophils + stubborn infections! 👎💊

Substances found in urinary sediment that are more easily distinguished by the use of a polarized microscope are: A) WBC B) RBC C) Waxy casts D) Anisotropic cholesterol droplets

D) Anisotropic cholesterol droplets

When performing the rosette test to screen for Fetal Maternal Hemorrhage, what is considered the correct combination to avoid false positives and/or false negatives? A) Fetal cells D positive & mother is D negative B) Fetal cells D positive & mother is weak D positive C) Fetal cells weak D positive & mother is D negative D) Any combinations could cause false positive and/or false negative results with the rosette test

A) Fetal cells D positive & mother is D negative The fetal cells must be D positive, and the mother must be D negative for the rosette test to be valid. A false-positive result can occur if the mother is weak D positive. A false-negative result can occur if the fetus is positive for weak D.

What red blood cell component is indicated for patients who receive directed donations from immediate family members to prevent transfusion-associated graft versus host disease (TA-GVHD)? A) Irradiated Red Blood Cells B) Washed Red Blood Cells C) Leukocyte-reduced Red Blood Cells D) HLA matched Red Blood Cells

A) Irradiated Red Blood Cells

Illustrated in the top photograph is a 4-day old fugal colony cultured from a "ringworm" cutaneous infection. Although the appearance of the colony may suggest a presumptive identification, microscopic mounts prepared from the surface hyphae must be examined, as observed in the lactophenol blue stained tease mount in the bottom photomicrograph. With these observations, select from the multiple choices the identification of this dermatophyte. A) Microsporum canis B) Trichophyton mentagrophytes C) Epidermophyton floccosum D) Microsporum gypseum

A) Microsporum canis Choose Microsporum canis 🐾. Its colonies mature in about 1 week. Look for a lemon-yellow apron at the edge where conidia grow. You'll also see large, spindle-shaped macroconidia with a thick wall, each with a tapered terminal cell. Sometimes, you might find scattered microconidia too. M. canis is a zoophilic dermatophyte often passed from infected pets to humans. Trichophyton mentagrophytes 🐭 colonies look cottony or granular and are tan to cream-colored. No yellow ring on the edge. Under a microscope, you'll spot grape-like clusters of small spherical microconidia along thin hyphae. Macroconidia are cigar-shaped. Epidermophyton floccosum 🍂 colonies are gray-yellow or olive green. Microscopically, you'll see large, club-shaped macroconidia with smooth walls. They attach directly and laterally to hyaline hyphae. No microconidia. Microsporum gypseum 🏞️ colonies are cinnamon-brown with outward-projecting delicate hyphae. Under a microscope, you'll see large canoe-shaped macroconidia with rounded distal cells. This one usually stays in the soil and rarely infects humans.

These adult nematodes are round, elongated, typically look like an earthworm and can be found in decaying vegetation or moist soil. Of the following organisms listed, which one is a nematode? A. Ascaris lumbricoides B. Diphyllobothrium latum C. Taenia solium D. Hymenolepis diminuta

A. Ascaris lumbricoides Ascaris lumbricoides or roundworm is a common parasite found worldwide. Ascaris eggs remain viable and infective more often than eggs of any other helminth species. Diphyllobothrium latum, Taenia solium, and Hymenolepis diminuta are all cestodes. Cestodes are also known as tapeworms and are capable of self-fertilization.

Donor and recipient blood samples must be kept for at least how long after transfusion? A. 10 days B. 7 days C. 3 days D. 24 hours

B. 7 days Alright, here's the deal! The right answer is 7 days! 📆 Donor and recipient samples are must-haves for checking transfusion reactions, just in case! 👀 Antibody screening and crossmatch samples? Keep 'em less than 72 hours (3 days) old, but the full 7 days is the retention rule. 🗓️ And check this out: 5 days is too short for a reaction investigation, and 10 days? That's more than the needed 7 days. 🚫‍♂️ Easy peasy! 🌟

Hyperacute rejection of a transplanted organ is caused by: A) Pre-formed humoral antibodies in a patient B) Patient sensitization to donor antigens C) Development of allogeneic reaction to donor antigens D) Disturbance of host-graft tolerance

A) Pre-formed humoral antibodies in a patient The reason why some transplanted organs get rejected is because of different things happening in the body. 1. **Hyperacute rejection** happens when the patient's body already has antibodies that attack the new organ right away. These antibodies are usually against the ABO blood type or certain proteins on the cells (MHC antigens). 🚫 2. **Accelerated rejection** can occur when the patient's immune system quickly recognizes and attacks the new organ because it has encountered similar tissue before. This is like when the body remembers something it doesn't like. 🏃‍♂️ 3. **Acute rejection** is when the body's immune system reacts against the new organ after the first exposure to it. Initially, T cells are involved, but later on, antibodies and other immune proteins may join in. This can damage the organ. 4. **Chronic rejection** happens over time, usually after three months. It's a slow process where the body's immune system gradually damages the organ, leading to a decline in its function. This affects most people who receive transplants. 🕰️ So, rejection can happen quickly or slowly, but it's all because the body's defenses don't recognize the new organ as its own.

In cases where separate fungal cultures are incubated at both 30° C and 35°-37° C, a dimorphic yeast form may develop within 3-4 days as illustrated in the top photograph. The isolate is commonly recovered from puncture wounds of the fingers, wrists or arms among rose gardeners. The yeast colony has a smooth outer white border surrounding an inner pigmented center of growth that appear to be hyphal strands. What is the yeast identified by observing the microscopic features as illustrated in the bottom lactophenol stained mount? A) Sporothrix schenckii B) Histoplasma capsulatum C) Blastomyces dermatitidis D) Coccidioides immitis

A) Sporothrix schenckii 🍄 Sporothrix schenckii is a fungus 🌱 often found in gardens. It can change shape depending on the temperature 🌡️. At 22°C, it looks like mold with tiny conidia at the end of long strands and darker conidia along the sides. But at 37°C, it transforms into a yeast 🍞 with cigar-shaped cells that bud off. 🌱 🔍 Histoplasma capsulatum is another fungus 🍄 that produces small yeast cells in clusters. They have a spiny appearance 🌵 under the microscope. To diagnose it, we grow the mold on special agar at 37°C to make it turn into yeast cells. 🔬 Blastomyces dermatitidis yeast cells are bigger and rounder , with a daughter cell budding off from a broad base. In its mold form, it has short, egg-shaped conidia. 🌱 🔬 Coccidioides immitis doesn't become a yeast 🚫, but it forms hyaline arthroconidia in its mold phase. These arthroconidia turn into spherules in tissues, but we can't see them in cultures.

Colligative properties of solutions include all of the following EXCEPT: A) The solution's pH B) Freezing point C) Osmotic pressure D) Vapor pressure

A) The solution's pH Colligative properties are properties of solutions that depend on the number of molecules in a given volume of solvent or the number of particles in the solution. Colligative properties include lowering of vapor pressure, the elevation of boiling point, depression of freezing point, and osmotic pressure.

The microorganism in the photographs was detected in muscle tissue. The most likely identification is: A) Trichinella spiralis encysted larva B) Strongyloides stercoralis filariform larva C) Hookworm rhabditiform larva D) Taenia solium cyst

A) Trichinella spiralis encysted larva - Trichinella spiralis is the most likely identification as it is the only nematode known to encyst in human muscle tissue and has a distinctive coiled shape. - Strongyloides stercoralis does not encyst in muscle tissue. - Hookworm filariform larvae are found in soil contaminated with fecal material, not in muscle tissue. - Taenia solium encysts in human tissue, but it does not produce the spiral shape shown in the photographs.

Once Fresh Frozen Plasma (FFP) has been thawed, it should be stored at what temperature? A. 1 - 6 ºC B. 30 - 37 ºC C. 20 - 24º C D. 45 - 56º C

A. 1 - 6 ºC Here's the lowdown! Thawed FFP chills at 1-6°C and should party in a transfusion within 24 hours. ❄️📆 Thawing? It happens in a 30-37°C water bath, but storage stays cool at 1-6°C. 🛁❄️ Platelets hang out at 20-24°C. 🌡️ No blood components get cozy at 45-56°C. 🚫🔥

Red blood cell units with CPD (citrate-phosphate-dextrose) can be stored for up to how many days? A. 21 days B. 28 days C. 35 days D. 42 days

A. 21 days Alright, let's keep it simple! A) RBC units with CPD or CP2D: Store 'em for 21 days. 📆 B) Irradiated RBC units: Good for 28 days or the original date, whichever is first. ☢️📆 C) CPDA-1 RBC units: Keep 'em fresh for 35 days. 🏡📆 D) Additive solution RBC units: Last up to 42 days. 📆 Easy peasy! 🌟‍♂️

Which morphologic term describes this slide? A. Alder-Reilly neutrophils B. Auer rods C. Döhle bodies, bacteria, toxic granulation D. Pelgeroid neutrophils

A. Alder-Reilly neutrophils Alder-Reilly anomaly: Inherited autosomal recessive. WBCs have granules with mucopolysaccharides, stain red on Wright stain (not dark purple/blue). Qualitative changes resemble toxic granulation. More neutrophils affected in Alder-Reilly; granulation in all leukocytes. 🔍 Auer rods: Seen only in malignant myeloblasts and promyelocytes. Pink rods in cytoplasm. 👀🔬 Döhle bodies, toxic granulation, and bacteria: Seen in sepsis. Döhle bodies = small blue-gray cytoplasmic inclusions. Bacteria are dark staining and larger than granules. 🔬 Pelgeroid cells: Hyposegmented neutrophils with one or two lobes. 👶🔬

For which of the following antibodies is the DAT most likely to be NEGATIVE when testing a newborn for possible HDFN? A. Anti-A,B B. Anti-c C. Anti-D D. Anti-K

A. Anti-A,B While the DAT is usually positive in ABO HDFN, it's likely to be negative in this scenario. Washing during the test might break the bonds between anti-A,B and the baby's underdeveloped A (or B) antigens. 🚿 For alloantibody HDFN, like anti-D, anti-c, or anti-K, expect a positive DAT! 👶✨

Which of the following statements is correct regarding total laboratory automation (TLA)? A. Back-end systems may include the removal of specimens from the analyzer. B. Front-end systems may include the removal of specimens from the analyzer with transport to storage. C. Front-end systems may include retrieval from storage. D. Back-end systems may include the identification of specimens.

A. Back-end systems may include the removal of specimens from the analyzer. TLA refers to automated devices and robots 🔬 integrated with existing analyzers to perform all phases of laboratory testing. Back-end systems may include removal of specimens from the analyzer and transport to storage 📦🚛, retrieval from storage for retesting 🔁, re-aliquoting, or disposal 🗑️. Front-end systems can identify and label specimens 🏷️, centrifuge the specimen and prepare aliquots , and sort and deliver samples to the analyzer .

The name of the rapid test seen in the image, often used to differentiate S. pneumoniae from viridans streptococci, in which a drop of 10% deoxycholate was placed on an area of growth, is: A. Bile solubility test B. Bile esculin hydrolysis C. Optochin susceptibility test D. Bacitracin susceptibility test

A. Bile solubility test Correct answer: Bile solubility test! 🔍 S. pneumoniae colonies disappear with 10% deoxycholate, thanks to amidase and bile salts lowering surface tension. Viridans streptococci colonies stay visible! Bile esculin test: Identifies enterococci and Streptococcus bovis group. Positive reaction for enterococci and group D streptococcus, negative for non-group D viridans streptococcus. 📊 Optochin susceptibility test (P disk test): Differentiates S. pneumoniae from viridans streptococcus. Optochin lyses pneumococci; alpha streptococci are resistant. Positive if inhibition zone > 14 mm. 🛡️ Bacitracin Susceptibility: Presumptive test for beta-hemolytic group A streptococci (Streptococcus pyogenes). Susceptible to 0.04 units bacitracin, unlike other resistant beta-hemolytic streptococci. 💉

This suspicious form recovered from a stool specimen measures 165 µm by 65 µm. It is responsible for causing: A. Bilharziasis (schistosomiasis) B. Paragonimiasis C. None; considered non-pathogenic D. Dog tapeworm infection

A. Bilharziasis (schistosomiasis) The 🐛 pictured is a Schistosoma mansoni egg, which can be identified by its large size, oblong shape, and prominent lateral spine. The condition associated with this parasite is known as bilharziasis or schistosomiasis 🔬. Paragonimiasis is caused by Paragonimus westermani. The egg of P. westermani is oval with a prominent operculum with rim . The size of the egg ranges from 78-120 µm by 45-60 µm. All Schistosoma species are pathogens and cause various diseases depending on the species. They are differentiated by the placement and size of the spine ⚔️. Dog tapeworm infection is caused by Dipylidium caninum. It mainly affects dogs and cats, rarely causing disease in humans. In a stool specimen, D. caninum is found in an egg pocket, with each pocket containing 5-30 eggs. The individual eggs are 30-60 µm in size 🐶🐱.

Which of the following is the proper designation for the pluripotential stem cell that is a precursor for both myeloid and lymphoid cell lines? A. CFU-S B. CFU-GEMM C. G-CSF D. CFU-GM

A. CFU-S CFU-S stands for colony-forming unit spleen - it is the pluripotential stem cell that gives rise to all cell lines. CFU-GEMM is a multilineage precursor for granulocyte, erythrocyte, macrophage, and megakaryocyte. G-CSF is the precursor committed to granulocyte cell lines. CFU- GM is the precursor for granulocyte and monocyte cell lines.

Which one of the following cardiac biomarkers could detect a recent reinfarction? A. Creatine kinase MB (CK-MB) B. Troponin I (TnI) C. Troponin T (TnT) D. Lactate dehydrogenase (LD)

A. Creatine kinase MB (CK-MB) ⏰ Following an acute myocardial infarction (AMI), CK-MB returns to normal ranges in 48-96 hours. If a patient has a second AMI in this time period, a second rise in CK-MB concentrations would be seen. This is not true for the cardiac troponins as they remain elevated for much longer following an AMI: TnT for 8-21 days and TnI for 7-14 days. ⚡️ 💉 LD levels are elevated for up to one week following AMI. LD levels can also be falsely elevated in hemolyzed samples, as LD is in higher concentration intracellularly. ❗️🔬

What does a positive Clinitest result indicate in a urine sample? A. Elevated glucose levels in the urine. B. Increased protein levels in the urine. C. Presence of ketones in the urine. D. Abnormal pH in the urine.

A. Elevated glucose levels in the urine.

The egg is the infective stage of this parasite for humans. What is the identification of this organism? A. Enterobius vermicularis B. Taenia solium C. Trypanosoma cruzi D. Schistosoma mansoni

A. Enterobius vermicularis Enterobius vermicularis (🐛 also known as Pinworm) infects humans after 🍽️ ingestion of eggs. The eggs migrate to the digestive tract, to the small intestine, where they hatch 🐣 and release larvae. Although Schistosoma mansoni () and Taenia solium (🐷) have eggs in their corresponding life cycles, this form is not the infective stage for human infections. Taenia solium infects humans after 🍽️🐷 ingestion of pork contaminated with cysticercus larva. This larva consists of a scolex (🔬) surrounded by a thin-walled cyst filled with fluid. The larvae will emerge in the small intestine, mature, and release eggs. Those eggs are consumed by the animal species (🐷), in which the larva will deposit in the tissues. Trypanosoma cruzi () does not have an egg stage at all. T. cruzi is a hemoflagellate and requires an arthropod vector (the reduviid bug) for transmission. When the bug bites a human, infective trypomastigotes are deposited next to the bite. Humans will scratch the bite and rub these into the area and into the host. Schistosoma mansoni infection occurs through the water-residing cercaria, which enters the human body by drilling into the skin. They migrate to the bloodstream where they mature and reside in the veins surrounding the intestinal tract. The females lay eggs. The reach water and release the miracidium that must find a snail host to develop into cercaria. The egg is not the infective form for humans.

What is a typical finding for determining the endpoint for the initial or iron-depletion phase of treatment for hereditary hemochromatosis (HH)? A. The serum ferritin decreases to between 20 and 50 ng/mL B. The hepatic iron index returns to normal C. The transferrin saturation drops below 20% D. The serum iron falls to below 35 µg/dL.

A. The serum ferritin decreases to between 20 and 50 ng/mL Hereditary hemochromatosis (HH): Absorbs too much iron, storing excess in bone marrow, heart, and liver. Initial treatment phase ends when serum ferritin drops to 20-50 ng/mL. Ferritin levels fall rapidly as storage iron depletes. Serum ferritin test is cheap and non-invasive. 💉💔 Hepatic iron index: Calculates liver iron concentration, indicating excess iron. Invasive and costly, requires liver biopsy. 💉💰 Transferrin saturation and serum iron: Decrease after iron stores deplete, but not the first indicators of successful HH treatment. 📉💉💊

The morphologic structures found in select tapeworms that are typically responsible for attaching to the human intestinal wall are called: A. Hooklets B. Polar plugs C. Operculums D. Polar thickenings

A. Hooklets Hooklets are structures attached to the rostellum of tapeworms (Cestodes). These hooklets aid in the attachment of the worm to the host's intestinal lining. An example of a cestode with hooklets is Taenia solium. 🐛 🍋 Polar plugs are characteristic features that aid in identifying the Trichuris species. The ends and oval shape give the organism a lemon-drop appearance. These structures do not aid in the organism's attachment to the intestinal lining. Trichuris is a nematode, not a cestode. 🐛 🔓 A number of helminth eggs (primarily cestode & trematode eggs) have an operculum. This lid structure opens under the appropriate conditions, allowing the egg contents (larva) to escape and continue their development. This structure does not aid in the organism's attachment to the intestinal lining. 🔍 Polar thickenings are characteristic features that aid in identifying the Hymenolepis species. These thickenings do not aid in the organism's attachment to the intestinal lining. 🐛

The stage of Ixodes tick most likely to transmit Lyme disease is: A. Nymph B. Larva C. Adult D. Egg

A. Nymph Nymph stage of Ixodes tick: Likely Lyme transmission in spring/summer, active when people outdoors. Needs 24 hrs attachment for spirochete transfer. Small size may go unnoticed, allowing transmission. 🌳🕰️ Ixodes larva stage: Hatches in summer of first year, acquires Borrelia from small rodents. Less likely to transmit than nymph stage. 🐁🔬 Adult stage of Ixodes tick: Late summer of second year, less likely Lyme transmission. Larger and more noticeable when attached. 🌞👀 Egg laid by female: Late spring on the ground. Hatches to larva, acquires Borrelia from small animal. Doesn't attach to host for transmission. 🔍

All of the following are reasons for conducting compatibility testing EXCEPT: A. Prevent recipient alloimmunization B. Verify ABO and Rh C. Select proper blood products D. Detect antibodies against donor cells

A. Prevent recipient alloimmunization Compatibility testing in the blood bank lab detects incompatibilities that may reduce donor red cell survival in the patient, but it can't prevent recipient alloimmunization to transfused cell antigens. Patients and donors aren't phenotyped for every antigen before transfusion. 🔬 Compatibility testing (pretransfusion testing) involves ABO and Rh verification, selecting appropriate blood products, and detecting antibodies against donor cells to prevent transfusion reactions.

On sheep blood agar, Haemophilus influenzae may exhibit satellitism around all of the following bacteria, EXCEPT: A. Pseudomonas spp. B. Neisseria spp. C. Staphylococcus spp. D. Streptococcus pneumoniae

A. Pseudomonas spp. 🔬 Neisseria, Staphylococcus, and Streptococcus pneumoniae are like "Hey H. influenzae, we got your back with enough V factor for growth!" But Pseudomonas is like, "Nah, not in my neighborhood." 🙅‍♂️ Enter the "satellite test" technique! 🌌 Tiny Haemophilus colonies appear in the hemolytic zone around a streak of S. aureus on sheep blood agar. 💢 It's like a secret handshake for presumptive Haemophilus ID. 🕵️‍♂️👾

The light pink-yellow, mucoid, non-hemolytic colonies on blood agar, an uncommon isolate, belongs to the aerobic actinomycetes. This species is widely spread among farm animals and may cause human respiratory infections upon animal contact. The Gram stain reveals Gram-positive cocci, with younger colonies also showing branching bacilli, with residuals seen here. Carbohydrates were not utilized (asaccharolytic), and the decarboxylase reactions are also negative. The presumptive identification is: A. Rhodococcus equi B. Nocardia asteroides C. Oerskovia turbata D. Streptomyces species

A. Rhodococcus equi 🔬 Rhodococcus equi: Smooth, mucoid, or rough colonies, can turn pink. Gram-positive cocci, cocco-bacilli in short chains. No love for casein, tyrosine, and xanthine; urease-negative. Hangs out in soil and animal dung, may bug humans on contact. 🌱🐴 Nocardia asteroides: Velvety to chalky colonies, maybe wrinkled and brown-yellow. Gram-positive bacilli, thin and branched. Low-key with casein, tyrosine, and xanthine; urease-positive. Not much of a threat, chills with immune-compromised buddies, causes infections in cozy places. 💤👾 Actinomadura madurae: Small, white to pink, molar tooth look after 2 weeks. Moderate branching with spores. Likes casein and nitrate, not a fan of urea. Causes actinomycetomas, peritonitis, wound infections, pneumonia, and bacteremia. Streptomyces species: Smooth to granular colonies, light yellow-brown pigment. Long, slender, branching Gram-positive bacilli. Loves casein, tyrosine, and xanthine. Hangs in the soil, but may cause respiratory and skin drama in humans. 🌿💊😷

Which one of the following parasites is the causative agent of Katayama fever? A. Schistosoma mansoni B. Strongyloides stercoralis C. Enterobius vermicularis D. Taenia saginata

A. Schistosoma mansoni Schistosomes cause Katayama fever. Their eggs are easy to spot with large size, unique shape, and a species-specific spine. "Schistosome" got its name from the male's groove for female copulation! ‍♂️💑 Strongyloides stercoralis larva = threadworm, looks like twisted thread! 🐛 Enterobius vermicularis = pinworm, with a sharply pointed posterior end! 📍 Taenia saginata = beef tapeworm, found in beef! 🐄🐛

An organism isolated from a sputum specimen appeared as a dry, wrinkled, off-white colony on sheep blood agar. A Gram stain was performed and Gram-positive branching rods were seen. In addition, a modified acid-fast stain was performed and was positive. The organism was later identified as a Nocardia species. Which of the following antibiotics is the appropriate treatment? A. Sulfonamides B. Erythromycin C. Rifampin D. Streptomycin

A. Sulfonamides Correct answer: Sulfonamides! 👍 They're the go-to for Nocardia infections. Also, consider amikacin, ceftriaxone, cefotaxime, linezolid, imipenem, and minocycline. Combo with sulfa and a primary agent for serious cases! 💊💪 Incorrect answers: Erythromycin and Rifampin. They treat Rhodococcus, Gordonia, and Tsukamurella species infections. 🚫 Streptomycin is a no-go too! It's for Streptomyces species infections. 🚫

Which of the following autoantibodies are found in a patient with Hashimotos thyroiditis? A. Thyroid-stimulating hormone receptor antibodies (TRAbs) B. Antithyroid peroxidase (TPO) C. Islet cell antibodies D. Antitransglutaminase (tTG)

B. Antithyroid peroxidase (TPO)

All of the following are considered cutaneous porphyrias, EXCEPT? A) Porphyria cutanea tarda B) Acute intermittent porphyria C) Congenital erythropoietic porphyria D) Erythropoietic protoporphyria

B) Acute intermittent porphyria The correct answer is acute intermittent porphyria, as this is a neurological (also termed neuropsychiatric) porphyria. Porphyria cutanea tarda, Congenital erythropoietic porphyria, and Erythropoietic protoporphyria are all cutaneous porphyrias.

Laboratory diagnosis techniques that utilize water are NOT recommended for the identification of which of these parasites? A) Cryptosporidium parvum B) Blastocystis hominis C) Toxoplasma gondii D) Balantidium coli

B) Blastocystis hominis 🔬 Lab tests with water ☔ and other liquids are a no-go for finding Blastocystis hominis. They tend to break down this parasite's forms 😵, giving wrong results ❌. But don't worry! Water doesn't bother C. parvum, T. gondii, or B. coli at all! 😄

Which dye-binding method uses an increase of absorbance at 595 nm to determine the total protein concentration of the specimen? A) Bromophenol blue B) Coomassie brilliant blue 250 C) Amido black 10B D) Ponceau S

B) Coomassie brilliant blue 250

The India ink preparation is used for presumptive identification of which organism? A) Aspergillus niger in blood B) Cryptococcus neoformans in CSF C) Histoplasma capsulatum in CSF D) Candida albicans in body fluids

B) Cryptococcus neoformans in CSF

Observed in this photomicrograph of a histological section of the duodenum are small, 5 µm in diameter spores adhering to the surface epithelium. Although a presumptive identification can be made by demonstrating acid-fast staining of these spores, monoclonal antibody-based DFA assays of stool specimens provide a more definitive identification. Select the probable identification. A) Cyclospora species B) Cryptosporidium species C) Cystoisospora belli D) Microsporidium species

B) Cryptosporidium species Cryptosporidium species 😷 = correct! Look for small oocysts (4-6 µm) with acid-fast appearance on duodenal mucosa. This might mean Cryptosporidiosis! But 🕵️‍♂️, monoclonal antibody-based tests can confirm the diagnosis if you suspect this infection. Cyclospora oocysts : they're lightly acid-fast and bigger (8-10 µm). Also, they look wrinkled! Cystoisospora oocysts 😲: big ones (25 µm) and shaped like spindles. Microsporidium spores : they're tiny (0.7-4 µm), not acid-fast, but they stain positive with Weber stain. You'll find them inside intestinal cells, not just on the surface.

Which of the following molds is classified as a zygomycete? A) Microsporum nanum B) Cunninghamella species C) Trichophyton schoenleinii D) Epidermophyton floccosum

B) Cunninghamella species Cunninghamella species are zygomycetes. Members of this order are rapidly growing organisms normally found in the soil. They are often opportunistic pathogens in immunocompromised hosts. Zygomycetes generally produce profuse, gray to white, aerial mycelium characterized by the presence of hyaline, sparsely septate hyphae. Microsporum nanum, Trichophyton schoenleinii, and Epidermophyton floccosum are all species of dermatophytes. Dermatophytes contain the largest number of organisms that are causative agents of mycoses, including cutaneous, subcutaneous, and systemic disease. Organisms are placed into this group when no mode of sexual reproduction has been identified.

Which of the following parasites is known to contain ingested red blood cells in the trophozoite morphologic form? A) Endolimax nana B) Entamoeba histolytica C) Entamoeba hartmanni D) Entamoeba dispar

B) Entamoeba histolytica The trophozoites of Entamoeba histolytica and Entamoeba dispar (both found in the stool) look very much alike. If you see red blood cells inside them, it's a sign of Entamoeba histolytica. Endolimax nana looks like a smaller version of Entamoeba coli but without red blood cells inside. Entamoeba hartmanni is similar to Entamoeba histolytica but lacks red blood cells inside. Entamoeba dispar is almost the same as Entamoeba histolytica but without red blood cells, and it's not harmful.

Which type of kinetic reactions are reactions in which the enzyme is in excess and the substrate concentration is the limiting factor? A) Zero order B) First order C) Second order D) Third order

B) First order First, imagine first-order reactions like a race 🏁 where there are lots of speedy runners (enzymes) but not many medals (substrates). So, the number of runners doesn't matter much—it's all about how fast they can grab the medals. Now, in zero-order kinetics, it's like a pizza 🍕 party where the rate of eating pizza stays the same no matter how many slices are on the table. It's all about how hungry (or full) you are, not how much pizza is available. But hey, hold up! Second and third order? Nah, those are like unicorns in this enzyme world—they're not terms we use when talking about enzymes in the lab. They're like characters in a fairy tale, not part of our scientific story.

Hydrogen ion concentration (pH) in blood is usually determined by means of which of the following electrodes? A) Silver B) Glass C) Platinum D) Platinum-lactate

B) Glass

The most common testing method for vitamin E determination is by: A) Protein binding radioimmunoassay (RIA) B) High-performance liquid chromatography (HPLC) C) 2,4-dinitrophenylhydrazine D) Not assayed - prothrombin time is used as a functional indicator of vitamin D status.

B) High-performance liquid chromatography (HPLC) HPLC 😊 is like the superhero method for measuring vitamin E! It checks for the coolest and most powerful type of vitamin E, alpha-tocopherol. 😎 B12 gets tested using RIA methods. 😊 To find out how much vitamin C (ascorbic acid) is in something, scientists often use 2,4-dinitrophenylhydrazine. Vitamin K doesn't get measured directly. Instead, doctors look at prothrombin time to see how well vitamin K is working.

The adult liver fluke, Fasciola hepatica can be identified by its relatively small size and cone-shaped anterior extension (arrow). How do humans become infected with this organism? A) Ingestion of poorly cooked meat B) Ingestion of poorly cooked water plants C) Bite of infected fly or insect D) Direct skin contact with contaminated soil

B) Ingestion of poorly cooked water plants Eating poorly cooked water plants 🌿 is right! 🎉 This is how you can get infected by a fluke. These tiny creatures stick to the plants and make us sick when we eat them uncooked or not cooked well. 😷 But eating poorly cooked meat 🍖 is wrong! ❌ Trichinella spiralis is an example of a nasty worm that can make us sick if we eat raw or undercooked pork or other animal meat with baby worms in them. 🐷 Getting bitten by a bug is also wrong! ❌ Leishmania and malaria can make us sick if an infected fly or mosquito bites us. 💉 Touching dirty soil with your skin 👣 is also not the right way! ❌ This usually happens with hookworms when we touch contaminated soil with our hands or walk barefoot where these worms live. 🚫

Which of the following cells are lining cells that could be seen in a peritoneal fluid? A) Choroidal cells B) Mesothelial cells C) Ependymal cells D) Squamous epithelial cells

B) Mesothelial cells Mesothelial cells 😊 line serous cavities like the pleural, peritoneal, or pericardial fluid. Choroidal cells are in the choroid plexus lining. Ependymal cells line ventricles and neural canal. Squamous epithelial cells 💁‍♂️💁‍♀️ line the lower portion of the male urethra and female vagina/urethra.

All of the following are directly involved in the production of semen EXCEPT? A) Prostate B) Pituitary gland C) Seminal vesicles D) Bulbourethral gland

B) Pituitary gland

What is the cell indicated by the arrow in this illustration? A) Basophilic lymphocyte B) Plasma Cell C) Small Lymphocyte D) Metamyelocyte

B) Plasma Cell

All of the following are true of lab results of patients with Glanzmann thrombasthenia EXCEPT? A) Deficient GPIIb/IIIa B) Severe thrombocytopenia C) Increased bleeding time D) Abnormal platelet aggregation with ADP, collagen, and epinephrine

B) Severe thrombocytopenia The correct answer is severe thrombocytopenia. Patients with Glanzmann thrombasthenia typically have normal platelet counts. The issue for patients with Glanzmann thrombasthenia is abnormal platelet function, not low platelet counts. The remaining answer options are all characteristic lab findings or disease characteristics of Glanzmann thrombasthenia.

Which culture medium is specifically formulated to recover Salmonella typhi from stool specimens? A. Selenite broth B. Bismuth sulfite agar C. Salmonella/Shigella (SS) agar D. Deoxycholate citrate agar

B. Bismuth sulfite agar 🔍 The correct answer is bismuth sulfite agar. It contains bismuth sulfite and brilliant green, which inhibit most enteric bacteria except Salmonella typhi and other salmonellae. 🔬 Selenite broth is used to inhibit the growth of E.coli and other coliform bacilli, but it needs to be subcultured to another media, usually bismuth sulfite agar. 🔬 🔒 SS agar is selective for Salmonella and Shigella. 💥 🔒 Deoxycholate citrate agar is selective for Salmonella paratyphi. 🍽️

Human dog bite infections may be caused by each of the following bacterial species EXCEPT: A. Pasteurella multocida B. Capnocytophaga ochracea C. Capnocytophaga cynodegmi D. Neisseria weaveri

B. Capnocytophaga ochracea 🐶 Capnocytophaga ochracea is like "nah, I'm chillin' in human mouths." 🙊 No dog bite drama for this one! 🚫 But hey, all the other bacteria in the list are like, "Yeah, we're doggo mouth buddies!" 🐕 So, they might join the party in human dog bite infections. 😬 Watch out for those canine bacteria adventures! 💢

Which of the following actions describes the MAJOR property of antidiuretic hormone? A. Acts on proximal tubules. B. Changes distal tubule water permeability. C. Acts on Na/K/(H') pump. D. Cannot be affected by diuretics.

B. Changes distal tubule water permeability. ADH, or antidiuretic hormone, saves body water by controlling urine loss in the distal tubule and collecting duct. More ADH = concentrated urine, less water lost. Less ADH = collecting ducts release more water in urine. 🚰👉💧/🚫💧

The properties of enzymes are CORRECTLY described by which of the following statements? A. Enzyme activity is not altered by heat denaturation. B. Enzymes are protein catalysts of biological origin. C. Enzymes are stable proteins and unaffected by pH changes. D. Enzymes affect the rate of a chemical reaction by raising the activation energy needed.

B. Enzymes are protein catalysts of biological origin. The only correct choice is choice 2, as enzymes are protein catalysts of biological origin. Enzymes are altered by heat denaturation, are affected by pH changes, and affect the rate of a chemical reaction by decreasing the activation energy needed.

When parasites are observed in clinical stool specimens, antigen detection is the preferred method for identification, providing increased sensitivity over more common microscopy techniques. This H & E - stained tissue section of the duodenum illustrates the presence of an intra-luminal intestinal trophozoite in which an antigen assay might be helpful in making a definitive identification. Select the presumptive identification from the choices listed. A. Chilomastix mesnili B. Giardia duodenalis C. Dientamoeba fragilis D. Pentatrichomonas hominis

B. Giardia duodenalis Correct identification: Giardia duodenalis (lamblia)! 🔬 Pear-shaped trophozoite with two laterally placed nuclei, flagellum, known as "old man face." If uncertain, Giardia antigen testing on duodenal fluid aspirate might help. 👴👁️💉 Incorrect responses: 🚫 Chilomastix mesnili: Pear-shaped trophozoite, single large anterior nucleus. Non-pathogenic; negative for Giardia antigen. 🍐🚫 Dientamoeba fragilis: Pear-shaped trophozoite, two distinctive nuclei with granulated karyosomes. Negative for Giardia antigen. 🍐🚫 Pentatrichomonas hominis: Tear-drop trophozoite, single dark-staining nucleus beneath anterior membrane. Non-pathogenic; negative for Giardia antigen. 😢🍐🚫

A bone marrow biopsy from a 50-year-old patient that has an overall cellularity of 20% (i.e., 80% fat and 20% hematopoietic cells) is considered: A. Normocellular B. Hypocellular C. Hypercellular D. Monocellular

B. Hypocellular For a quick estimate of expected bone marrow cellularity in adults, subtract the age from 100%. The normal range is within +/- 10 of that number. A healthy 50-year-old should have a cellularity between 40% and 60%. ‍⚕️📊 At 50, the bone marrow typically has a 1:1 ratio of cellular elements to fat cells, with around 50% fat and 50% hematopoietic cells. 🔍 If there's more fat and fewer cells, it's considered hypocellular. ⚖️

What additional information is required on a label or tie tag of an autologous unit? A. Name of the ordering physician B. Identification of the recipient C. Location of the collection facility D. The statement "For Emergency Use Only"

B. Identification of the recipient In addition to the routine labeling of the autologous blood bag, the name of the donor, the recipient, the blood group, and the name of the hospital must be included along with the phrase "for autologous use only."

Which of the following conditions may produce the findings indicated by the arrows in the image on the right? A. Sepsis B. May-Hegglin anomaly C. Chediak-Higashi syndrome D. Alder-Reilly anomaly

B. May-Hegglin anomaly May-Hegglin anomaly: Rare autosomal dominant trait. Granulocytes have RNA inclusions and giant platelets. No symptoms except occasional bleeding due to low platelet counts. ‍♂️ Toxic changes: Neutrophils show toxic granulation, vacuoles with sepsis. 🔬 Chediak-Higashi syndrome: Rare autosomal recessive disorder. Neutrophilic granules fuse, inhibiting function. No giant platelets. ‍♀️ Alder-Reilly anomaly: Inherited. Large purple granules in all leukocytes. 💜

What is the rare phenotype found exclusively in male patients that is caused by X-linked inheritance from a carrier mother, often demonstrating a chronic but well-compensated anemia as well as muscle and nerve disorders? A. Fy (a- b-) B. McLeod C. Jk (a- b-) D. U-

B. McLeod Correct answer: McLeod phenotype! ❌🔬 Lacks Kx and Km antigens, low expression of other Kell Blood Group antigens. Linked to X-linked chronic granulomatous disease (not always). 👾 Fy(a-b-) phenotype: Found in African Americans, linked to resistance against P. vivax malaria. 🌍🚫 Jk(a-b-) phenotype: Very rare, often in Polynesian population. 🏝️ U- phenotype: Extremely rare, only in individuals both S- and s-. 🚫💉

What is the first step of the ethyl acetate concentration procedure? A. Centrifuge specimen to obtain four layers B. Mix fresh stool specimen with 10% formalin and strain to obtain a sediment C. Add normal saline, centrifuge. and decant the supematant fiuid D. Resuspend the sediment with 10% formalin and add ethyl acetate

B. Mix fresh stool specimen with 10% formalin and strain to obtain a sediment Mix the fresh stool specimen with 10% formalin and strain to obtain a sediment is the correct answer because the purpose of the ethyl acetate concentration procedure is to remove fecal debris. Filtering the specimen removes large pieces of debris. (First Step) Add normal saline, centrifuge, and decant the supernatant fluid is incorrect because this is the washing step of the procedure to remove smaller pieces of debris. (Second Step) Resuspend the sediment with 10% formalin and add ethyl acetate is incorrect because this is the preservation step of the procedure. Ethyl acetate is added to introduce specific gravity differences into the testing environment. (Third Step) Centrifuge specimen to obtain four layers is incorrect because this is the last step in this procedure. By centrifuging the specimen after the addition of ethyl acetate, the parasites are heavier and will sink to the bottom of the tube. The formalin layer will be above the sediment. The debris/fat layer will be above the formalin, and the ethyl acetate layer will be at the top. (Last Step)

Which of the following may be found in the cerebral spinal fluid (CSF) and measure approximately 15 µm? A. Acanthamoeba species cyst B. Naegleria fowleri trophozoite C. Toxoplasma gondii bradyzoite D. Entamoeba gingivalis trophozoite

B. Naegleria fowleri trophozoite The correct answer is Naegleria fowleri trophozoite . These trophozoites are small, measuring 10-20 µm, and have a distinct appearance with a single nucleus and blunt pseudopodia. Naegleria fowleri is a type of amoeba found in brackish or fresh waters. It can enter the body through the nose while swimming in these waters. Once inside, it can travel to the brain and cause infection. 🏊‍♂️👃💥 The incorrect answers are: Acanthamoeba species cyst ❌: These cysts are larger, measuring 10-25 µm, and have a double cyst wall with a wrinkled outer wall. Acanthamoeba infections are associated with specific conditions like granulomatous amoebic encephalitis and corneal ulceration. 🚫🔬 Toxoplasma gondii bradyzoite ❌: These are observed in tissue samples, not cerebrospinal fluid. Toxoplasma gondii infections are typically diagnosed through serological testing. 🚫🔬💉 Entamoeba gingivalis trophozoite ❌: These trophozoites are commonly found in the oral cavity, not in cerebrospinal fluid. 🚫👄🔬

Illustrated in the top image is a 4-day growth of a dark brown, entire colony with a narrow outer white zone. The surface mycelium is glabrous and finely granular. As this colony is not specific, the fungal species identification must be made on stained mounts prepared from the surface of the mycelium. In the lactophenol blue mount shown in the bottom photomicrograph is the characteristic sac-like structure, a pycnidium, within which are contained small spiral, hyaline, one-celled conidia. Select the name of the fungal species represented in these photographs. A. Chaetomium species B. Phoma species C. Ulocladium species D. Curvularia species

B. Phoma species 🍄 Phoma species: Look for smooth to peppery mycelium, and check under the microscope for pycnidia housing tiny, spherical conidia. 👀🔬 🍶 Chaetomium species: Spot flask-shaped perithecia, standing out with hair-like extensions. Ascospores do their thing within the perithecium. 🍶💨 🌱 Ulocladium species: Fast-growing colonies in gray, olive-green, or black, rocking multi-celled, angular conidia on cool sympodial conidiophores. 🚀🌈 🌑 Curvularia species: Rapidly growing, cottony colonies in shades of gray to black. Microscopically, catch crescent-shaped conidia with 3-5 unevenly-sized cells. 🌪️👀

A sputum specimen for culture is processed in the laboratory. Upon reviewing the Gram stain, the tech finds there are about 15 epithelial cells per low power field and a mix of bacterial flora present. What should the tech do next? A. Report out the Gram stain and incubate sputum culture plates B. Reject specimen C. Report out Gram stain and discontinue culture D. Discard specimen

B. Reject specimen 📝🚫 This sputum specimen should be rejected due to the high number of epithelial cells present in the Gram stain. 🔬 Specimens with more than 10 epithelial cells per low power field and mixed flora indicate upper respiratory tract contamination and should not be cultured. 💥 ❌ The culture should not be continued due to the high number of epithelial cells present in the Gram stain. Sputum cultures are used to determine the presence of pneumonia, infection in the lower respiratory tract, and significant upper respiratory contamination will provide inaccurate results to the physician. 🔍 Gram stain for the culture should not be reported due to the epithelial cells present. 📊 Reporting can provide inaccurate or confusing results for the physician. 🙅‍♂️ 💡 Specimens should not be discarded before discussing the rejection reasons with the physician or healthcare provider that collected the specimen. 🗣️💼

This antinuclear antibody (ANA) pattern is characterized by granular staining in the nuclei of the interphase cells (a). There is also an absence of staining in the chromosomal area of the metaphase mitotic cells (b). The slide is viewed using fluorescent microscopy. Which pattern is this? A. Homogeneous B. Speckled C. Nucleolar D. Centromere

B. Speckled 🔬 To get a positive ANA, you gotta see a clear design in the cell nuclei! They use metaphase mitotic cells to help figure out this pattern. 🌀 In the pic, you see a speckled ANA pattern: little speckles in the cell nuclei (a) but none on the chromosomal area in dividing cells (b). No staining on the nucleoli means it's not a nucleolar pattern. 🚫 If it was a homogeneous pattern, you'd see the whole nuclei stained and some coloring in dividing cells. For centromere pattern, lots of little speckles in both interphase nuclei and dividing cell chromatin. 🌈🔍

Given the following laboratory results, what is the most likely diagnosis?HBsAg: Negative Anti-HBc: Negative Anti-HBs: Negative A. Acute Hepatitis B infection B. Susceptible to Hepatitis B infection C. Immune to Hep B due to past infection D. Immune to Hep B due to vaccination

B. Susceptible to Hepatitis B infection Hepatitis B surface Antigen (HBsAg) is the first viral protein to become positive after infection with 4-12 weeks, while Anti-Hepatitis B surface (Anti-HBs) antibody appears after resolution of acute infection and is not found in chronic states. It is also found in those with immunity from vaccination or past infection. Anti-HBc (core) antibody presents about 6 months post-infection and, if found, is a determinate of immunity from past infection.

Which of the following labels must be affixed to an autologous blood component that is shipped from the donor center without completing infectious disease testing? A. A blue sticker indicating which tests are in process. B. The phrase "Donor Untested." C. A statement from the ordering physician requesting the release. D. A red warning tag.

B. The phrase "Donor Untested." Alright, listen up! Autologous blood donations skip the infection test since they're just for the original donor. If not tested, slap a label saying "Donor Untested" and keep it away from the group donation scene. 🚫 Simple, right? 😎🌟

The following are organisms that are associated with their appropriate diagnostic specimens with the exception of: A. Entamoeba hartmanni - stool B. Trichomonas tenax- vaginal secretions C. Pentatrichomonas hominis - stool D. Entamoeba gingivalis- mouth

B. Trichomonas tenax- vaginal secretions 🔍 Trichomonas tenax - 🌸 vaginal secretions is the correct answer because Trichomonas tenax is seen only in preparations from the mouth. It is not found in vaginal secretions. 😮💦 🍽️ Entamoeba hartmanni - is an intestinal amoeba acquired through contaminated food and water. Therefore, a stool specimen is the most appropriate specimen for ova & parasite testing. 💩 🍽️ Pentatrichomonas hominis - is an intestinal flagellate acquired through contaminated food and water. Therefore, a stool specimen is the most appropriate specimen for ova & parasite testing. 💩 🌸 Entamoeba gingivalis - is found in the oral cavity. 😁

Compared to plasma frozen within 8 hours of collection, plasma frozen within 24 hours of collection will likely have reduced levels of Factor: A. II B. VIII C. X D. XI

B. VIII Plasma frozen in 24 hours (PF24/FP24) = clotting factors like 8-hr frozen plasma! ✨ But, PF24 may have less Factor V and Factor VIII! ⬇️🔬 Factors II, X, and XI in 24-hr frozen = fresh-frozen (8-hr frozen)! 🔄❄️

Delayed hemolytic transfusion reactions (DHTR) usually occur within which time period? A) 1 hour after transfusion B) 24 hours after transfusion C) 3-7 days after transfusion D) One year after transfusion

C) 3-7 days after transfusion The right answer is usually 3-7 days after getting blood . This is when your body might react to the transfusion. If it happens within 1 hour, it's an immediate reaction 😱. If it's after 24 hours, it's probably not due to the blood itself, maybe just a fever . But if it's a year later, it's likely not because of the transfusion .

For BEST results, if not tested immediately, a semen sample should remain at which of the following temperatures following collection? A) 4 ºC B) Room temperature C) 37 ºC D) -40 ºC

C) 37 ºC Preferably, a semen sample should remain at 37° C following collection, which helps to maintain sperm integrity. The specimen should be tested within 1 hour of collection.

Which of the following best describes the type of chemical lithium is? A) An anionic metal B) A synthetic salt C) A cationic metal D) A naturally-occurring salt

C) A cationic metal Lithium is a metal found in nature 🌿. It acts like sodium in our bodies and gets removed by our kidneys 🚽. People use it as a medicine to help with mood swings 🎭, like in bipolar disorder, sadness that keeps coming back , and when someone gets too aggressive .

Which of the following is the cause of cytopenia in Myelodysplastic syndromes (MDS)? A) Unchecked clonal hematopoiesis B) Inability to incorporate iron into developing erythrocytes C) Excess apoptosis D) Myelofibrosis

C) Excess apoptosis Too many abnormal cells dying -> less cells in blood -> not enough blood cells (😨 cytopenia). MDS = abnormal blood disease. If cells grew uncontrollably, blood counts would be high (like in Myeloproliferative diseases), but in MDS, the bad cells get destroyed in the bone marrow. 🔬 Some MDS, like RARS, have iron in cells, but it's because of messed-up development, not iron problems like in Sideroblastic Anemia. 💀 Myelofibrosis can cause low blood counts, but it's not a big deal in MDS.

What characteristics are most often associated with alpha thalassemia intermedia? A. No clinical abnormalities present B. Polycythemia, hepatomegaly C. Anemia, splenomegaly D. Erythroid hypoplasia

C. Anemia, splenomegaly Alpha thalassemia intermedia (Hemoglobin H disease): Microcytic, hypochromic anemia + splenomegaly. 👶🔬 Clinical abnormalities from birth: Physical + intellectual issues. 👶 Polycythemia: Increase in hemoglobin + hematocrit. Types include polycythemia vera, secondary polycythemia, and reactive polycythemia. Hepatomegaly less common than splenomegaly. 💉📈 Erythroid hyperplasia in thalassemia: Bone marrow boosts erythropoiesis due to anemia. 🔬

All of the following colony and microscopic descriptions are paired correctly with the mold indicated, EXCEPT: A) Macroscopic description: rose red or purple red pigmentation Microscopic description: multi-celled, sickle-shaped macroconidia Mold: Fusarium sp. B) Macroscopic description: greenish-gray or olive-black colony Microscopic description: branched septate hyphae with conidiophores bearing round conidia in chains Mold: Aspergillus sp. C) Macroscopic description: cottony white colony with black spores Microscopic description: black, globose, smooth-walled conidia borne in chains Mold: Rhizopus sp. D) Macroscopic description: velvety, grayish-green colony with a white border Microscopic description: septate hyphae with conidiophores bearing brown, oval conidia Mold: Penicillium sp.

C) Macroscopic description: cottony white colony with black spores Microscopic description: black, globose, smooth-walled conidia borne in chains Mold: Rhizopus sp. The right answer is: 🔍 Macroscopic description: green, granular, rugose colonies 🔬 Microscopic description: 📜 chains of spherical conidia produced from branching phialides; 🍄 Aspergillus sp. 💡"Chains of spherical conidia produced from branching phialides" is like describing Penicillium species. They usually make green, granular, rugose colonies. 💡"Multi-celled, sickle-shaped macroconidia" fits with Fusarium species. Their colonies look 🔴 rose red or purple-red. 💡"Dark, elliptical conidia each supported by a conidiophore ('lollipops')" is typical of Scedosporium apiospermum. Their colonies look grayish-brown. 💡The description of "tight clusters of spherical conidia held by finger-like phialides" matches with Gliocladium. Their colonies look like a "green lawn" across the Petri dish.

Donation of which apheresis blood product more than once every four weeks requires monitoring of total plasma protein and antibody levels? A) Red cell apheresis B) Plateletpheresis C) Plasmapheresis D) Leukapheresis

C) Plasmapheresis Plasma levels of total protein, IgG, and IgM levels must be monitored every four months in plasmapheresis donors because levels of these and other proteins present in plasma decrease following plasmapheresis. Blood components from red cell apheresis, plateletpheresis, and leukapheresis do not contain enough volume of plasma to necessitate the monitoring of plasma proteins.

Which of the following statements are true regarding the storage and handling of urinalysis chemical reagent strips? A) Variations in temperature during storage will not affect the effectiveness of the chemicals on the reagent pads. B) Touching the reagent areas of the strip will not interfere with test results. C) Remove only enough strips for immediate use. D) The bottle of reagent strips can remain uncovered once it has been opened.

C) Remove only enough strips for immediate use.

The 40 µm in diameter ovum in this photograph may be found in the stool specimens of individuals presenting with minimal abdominal discomfort and low grade diarrhea. Pairs of hooklets are observed internally in the absence of an internal membrane. Select from the multiple-choice answers the presumptive identification of this cestode ovum. A) Hymenolepis diminuta B) Diphyllobothrium latum C) Taenia spp. D) Dipylidium caninum

C) Taenia spp.

Which assay is recommended by the American Heart Association (AHA) and the Centers for Disease Control and Prevention (CDC) as the inflammatory marker of choice in the evaluation of cardiac heart disease risk? A) CRP B) BNP C) hs-CRP D) NT-proBNP

C) hs-CRP 🔬 The hs-CRP test 👩‍🔬 can find CRP even when it's super tiny! It shows if there's chronic inflammation and helps know heart 💔 risks. The American Heart Association (AHA) and the Centers for Disease Control and Prevention (CDC) recommended it in 2003 for checking heart risk! 💡 🔍 The regular CRP test measures inflammation during acute conditions, like 🔥 fever. It got famous as a sign of acute rheumatic fever. In 1947, they found CRP in people with 💔 heart failure, showing its link to heart issues. Shortness of breath is common in heart failure, but it can happen in other issues too. That's where BNP and NT-proBNP tests come in! They help tell if the trouble's in the heart or somewhere else, especially in emergency rooms and clinics. 🚑

Using the given formula and data, what is the standard error of estimate (Se) for this regression line? Point Reference Method (x) Test Method (y) x- y- (x-)(y-) (x-)² 1 2 0 -3 -5 15 9 2 4 5 -1 0 0 1 3 6 6 1 1 1 1 4 8 9 3 4 12 9 Total Average= 5 Average= 5 28 20 b = 1.4 a (y-intercept) = -2 A. 0.83 B. 0.96 C. 1.18 D. 6.21

C. 1.18 Standard error 🔢 is the estimated standard deviation of an estimate. 📏 It measures the uncertainty associated with the estimate. 📊 Compared with the standard deviations of the underlying distribution, which are usually unknown, standard errors can be calculated from observed data. 📈🔍📊

Once the seal on a unit of packed red blood cells is opened, how long can the unit be stored in the refrigerator prior to administration? A. 4 hours B. 12 hours C. 24 hours D. 48 hours

C. 24 hours If the seal on a packed RBC unit is opened or used to prepare a blood component in an open system, then the unit can be stored refrigerated (1-6°C) for up to 24 hours. The change in expiration time is necessary to reduce the risk of bacterial sepsis in the recipient.

Donated red blood cells that contain the anticoagulant CPDA-1 (citrate-phosphate-dextrose-adenine) may be stored up to how many days? A.21 days B. 28 days C. 35 days D. 42 days

C. 35 days Adenine in the solution? Red blood cells last 35 days, not just 21. 📆 CPD or CP2D? Good for 21 days. 📆🚫 Irradiated cells? Expiry at 28 days from irradiation or the original date, whichever comes first. ⏳📆 Additive solutions? Boost shelf life to 42 days. 🚀📆

How many microns are equivalent to one ocular micrometer at 40X given the following information? Stage micrometer: 0.4 Ocular micrometer: 53 A. 5 µm B. 0.50 µm C. 7.5 µm D. 0.75 µm

C. 7.5 µm 🔢🔬 The following formula is required to determine the number of µm equivalent to each ocular unit: 📐 (number of stage micrometer units X 1,000) µ / (number of ocular micrometer units) Inserting the values given in this question: (0.4 X 1,000) µ / 53 = 7.5 µm ✅ Therefore, each ocular unit = 7.5 µm

The ratio of whole blood to anticoagulant is very important in the PT assay; at which hematocrit level should the standard anticoagulant volume be adjusted? A. < 50% B. > 75% C. > 55% D. < 35 %

C. > 55% ⚠️ If the hematocrit value is >55% (like in polycythemia), the effect of anticoagulant is 💪 too strong to ignore. At this level, the plasma volume is lower and excess citrate binds more calcium ions needed for clotting tests. This leads to falsely prolonged clotting times in PT and APTT tests. 😱 The formula to correct the citrate to blood ratio is: Volume of sodium citrate = (1.85 X 10-3) X (100 - patient hematocrit) X volume of whole blood drawn. 📐

An aliquot of AS-1 red blood cells is being prepared from an intact packed cell unit using a sterile connection device. During the process of preparing an aliquot, the sterile device fails and blood drips onto the counter from the product tubing. What should be done with the primary unit? A. Destroy the unit. B. Keep the original expiration date. C. Change the expiration date to 24 hours. D. Change the expiration date to 48 hours.

C. Change the expiration date to 24 hours. Alright, let's simplify! Red blood cell aliquots are for patients not needing a full unit, like neonates and infants (less than 4 months old). 🍼 Indications include fetal or placental issues, twin troubles, obstetric accidents, and internal bleeding. To make aliquots, a closed system keeps the original outdate. 🔄🔒 But if it opens during the process, the outdate flips to 24 hours. ⏰❌ The unit's safe, no need to destroy, but the original expiration date is a no-go due to the system hiccup. 🚫📆 And 48 hours is too long; it's now good for 24 hours. 🕰️‍♂️ Easy, right? 🌟

Which of the following amoeba cysts measures approximately 25 µm? A. Entamoeba hartmanni B. Entamoeba histolytica C. Entamoeba coli D. Balantidium coli

C. Entamoeba coli Entamoeba coli ✅ is correct. Entamoeba coli cysts measure between 10 - 35 µm. 🔬📏 Size is an important parasite-identifying feature. It is especially significant in distinguishing Entamoeba histolytica from Entamoeba hartmanni. The size ranges of these and other amoebae often overlap. 🔄📏 Entamoeba hartmanni ❌ is incorrect because this amoeba measures less than 10 µm. 🚫📏 Entamoeba histolytica ❌ is incorrect because this organism measures between 10 - 20 µm. 🚫📏 Balantidium coli ❌ is incorrect because this amoeba measures between 50 - 75 µm. 🚫📏

This suspicious form that measured 20 µm, was recovered from sigmoidoscopic material. What is the identification of this organism? A. Pseudoparasite B. Entamoeba coli C. Entamoeba histolytica D. Entamoeba polecki

C. Entamoeba histolytica Of the three parasites listed here, only Entamoeba histolytica may be recovered in sigmoidoscopic material. 🔬 Entamoeba coli and Entamoeba polecki are only found in stool samples. 💩 The circular form of the organism indicates that it is a cyst form as opposed to a trophozoite form. E. histolytica cysts typically measure 8-22 µm. There is one nucleus with a small, central karyosome, and even peripheral chromatin. Also noticeable in the cytoplasm is a glycogen mass. Psuedoparasite means false or fake parasite or an artifact in the specimen that resembles a parasite. The key to differentiating a parasite and artifact is to look for defined edges and defined internal structures. In this image, the nucleus stands out as a distinct structure indicating it is a parasite and not an artifact. ❌ Entamoeba coli cysts are typically 8-35 µm. They contain 1-8 nuclei. The karyosome is typically large, irregular, and eccentric. There is also uneven peripheral chromatin present. Glycogen vacuoles may be seen also. There are also typically chromatoid bars with splintered ends seen in the cytoplasm that are absent from this image. 🔬 Entamoeba polecki cysts range in size from 10-20 µm. They typically have one nucleus with a small and central karyosome with evenly distributed peripheral chromatin. Glycogen and inclusion masses can be seen. They also typically contain chromatoid bars with pointed ends, which are absent in this image. 🔬

The upper image is a photomicrograph of a Gram stain prepared from a positive blood culture obtained from a 68-year-old female with an indwelling urinary bladder catheter. Smooth, gray, faintly beta-hemolytic colonies were recovered in subcultures of the positive bottle. The tubes shown in the lower photograph are: an esculin slant (left) displaying intense brown coloration a 6.5% sodium chloride broth (right) showing cloudy growth The most likely identification is: A. Non-Enterococcus Group D B. Streptococcus mitis C. Enterococcus faecalis D. Staphylococcus saprophyticus

C. Enterococcus faecalis Enterococcus faecalis: Gram-positive cocci in pairs and short chains. Esculin hydrolysis, grows in 6.5% NaCl. Can be alpha, beta, or gamma hemolytic on blood agar. 🔍 Non-Enterococcus Group D: Group D antigen common, but additional testing needed. Pediococcus species, Streptococcus gallolyticus possible. Variable reactions with bile esculin, 6.5% NaCl. 🚫 Streptococcus mitis: Alpha streptococcus, can't grow in high salt. Rare in urinary tract infections. PYR negative. 🏞️🚫 Staphylococcus saprophyticus: Gram-positive cocci in clusters. Involved in UTIs, grows in 6.5% NaCl. No esculin hydrolysis. 🚺🚫

The following urine test results were obtained from a 6-month-old African American infant who experiences vomiting and diarthea after milk ingestion and has failed to gain weight: pH: 5.0 Protein: Negative Glucose: Negative Ketones: Negative Blood: Negative Bilirubin: Negative Nitrite: Negative Urobilinogen: 0.1 EU/dL Clinitest: 2+ These results are clinically significant in which of the following disorders? A. Diabetes mellitus B. Lactose intolerance C. Galactosemia D. Cystic fibrosis

C. Galactosemia Galactosemia is an inherited metabolic disorder that affects an individual's ability to metabolize the sugar galactose effectively. Infants affected by galactosemia typically present with symptoms of lethargy. vomiting, diarrhea, failure to thrive, and jaundice. The presence of galactose in the urine sample is not picked up by the glucose pad on the urine test strip. However, the Clinitest result is positive since it can detect different sugars in the urine, including galactose, therefore diabetes mellitus would not be suspected for this patient. Cystic fibrosis would not be associated with the findings in this case. Im addition, the clinical symptoms and patient age differentiates lactose intolerance from galactosemia. True lactose intolerance will usually not become symptomatic in children until they are at least 3 years old (usually after age 7). Also, lactose intolerance is associated with diarthea, but not closely associated with vomiting.

For which determination is the brilliant cresyl blue stain used MOST often? A. Malaria - ring forms B. Plasma Cells C. Reticulocytes D. Basophilic stippling

C. Reticulocytes Reticulocytes = immature red cells with RNA remnants. Detect RNA through supravital staining (live cells). Brilliant cresyl blue, new methylene blue are supravital stains. 🔬💙 Malaria ring forms, plasma cells = Wright's stain. No need for supravital staining. 🔬🔍 Basophilic stippling = granules of ribosomes and RNA. Seen with supravital or Wright's stain. 🔬💉

Coccidia parasites are often acquired by fecal-oral routes by ingesting contaminated food or water. All of the following are coccidia parasites EXCEPT? A. Sarcocystis species B. Cryptosporidium parvum C. Trypanosoma cruzi D. Isospora belli

C. Trypanosoma cruzi Incorrect: Trypanosoma cruzi! 🚫 Not like Plasmodium or Babesia. No insect vector for sexual reproduction. It multiplies asexually by binary fission! 🐜💔 Sarcocystis, Cryptosporidium, Isospora = coccidian parasites. Contaminated food/water route! 🍔🚱 Plasmodium, Babesia = coccidia/sporozoa, insect vector spread! 🐜💨 Coccidia and sporozoa = both asexual and sexual reproduction in life cycles! ♻️💑

Nocardia species can be isolated from cutaneous specimens and can produce sulfur granules. These granules can be found in tissue specimens and can aid in detecting aerobic actinomycetes. To help identify the presence of sulfur granules in tissue specimens, which of the following methods will be most beneficial? A. Gram stain B. Acid fast stain C. KOH Mount D. Gomori methenamine-Silver (GMS)

C. KOH Mount KOH Mount ✅ is the correct answer because this is a rapid test that can detect sulfur granules in tissue. By performing a KOH mount on tissue specimens, proteinaceous material can be digested in order to detect the presence of sulfur granules. 🔬 Aerobic actinomycetes, such as Actinomadura species, Nocardia species, and Streptomyces species can grow in tissue as small, hard colonies, which are referred to as sulfur granules. 💥 Gram stain ❌ is incorrect because this test will detect the presence of Gram-positive or Gram-negative organisms. By performing a Gram stain test, the presence of aerobic actinomycetes can be detected by the presence of Gram-positive branching rods. This test will not detect the presence of sulfur granules. 🔍 Acid-fast stain ❌ is incorrect as this test is used to assist in identifying Nocardia species because Nocardia is weakly or partially acid-fast positive. This test does not detect the presence of sulfur granules. ❌ Gomori methenamine-Silver (GMS) ❌ is incorrect because this test is used to detect aerobic actinomycetes filaments from tissue specimens. It does not detect the presence of sulfur granules. ❌

In patients with Sickle cell disease, upon sickling what laboratory test will see an increase? A. MCV B. RBCs C. MCHC D. Hematocrit

C. MCHC MCHC: The winner! It's the concentration of hemoglobin in the blood, spiking when those cells go into sickle mode. 📈💉 📏 MCV: It's the average volume of red blood cells, but no big swings with sickle cell peeps. 🔄 👇 RBCs: Sorry, not more, but less! Sickle cells stress out and decrease the red blood cell count. 📉 🔴 Hematocrit: It's the ratio of red blood cells to total blood volume. But in sickle cell anemia, it's more of a decrease than an increase. 📉💉

Which of the viruses or diseases listed below is screened for in blood donors solely through questions asked during the donor screening and selection process? A. Hepatitis B B. West Nile Virus C. Malaria D. HIV

C. Malaria Currently, there's no FDA-approved test for checking malarial infections in donors; they just ask about travel to malaria-prone areas. For Hepatitis B and HIV, donors spill risky info, and tests like enzyme immunosorbent assays, chemiluminescent immunoassays, and NAT come into play. When it's West Nile Virus, no questions, just straight to NAT testing.

A peripheral smear demonstrates a population of red cells that are mostly 5 - 5.5 µm in diameter. The CBC data shows RDW of 13% (reference range 11.5-14.5%). Which of the following morphologies is consistent with these findings? A. Macrocytosis, low variation of cell volume B. Normocytic cell, low variation of cell volume C. Microcytosis, low variation of cell volume D. Normocytic cell, high variation of cell volume

C. Microcytosis, low variation of cell volume Quick Erythrocyte Facts Normal erythrocyte diameter: 7.5 µm (microcytic cells). RDW reference range: 11.5-14.5%, indicating anisocytosis. No increased volume variation observed in these microcytic cells. 🔍 More: Macrocytes have a diameter >7.5 µm (MCV >100 fL). High RDW signals increased variability in cell volume. ⚖️ In a nutshell: Microcytic cells with consistent volume! 📊 #HematologyFacts #Erythrocytes101

This suspicious form was recovered from a stool specimen. It measures 12 µm in length. Which of the following conditions is it responsible for when present? A. Amebiasis B. Amebic hepatitis C. None; considered non-pathogenic D. Traveler's diarrhea

C. None; considered non-pathogenic 🔬 This image shows a trophozoite of Chilomastix mesnili, a pear-shaped organism measuring 8-15 µm in length. It has a single nucleus at the front, a small karyosome, and lacks peripheral chromatin. C. mesnili has 4 flagella, 3 extending from the front and 1 from the cytostome. Cytosomal fibrils resembling a "shepherd's crook" are found near the cytostome. The posterior end has a spiral groove, giving it a curved appearance. 🚫 Chilomastix mesnili is non-pathogenic and not associated with any parasitic condition. It is transmitted through ingestion of cysts in areas with poor sanitation. Amebiasis and amebic hepatitis are caused by Entamoeba species, notably E. histolytica. Entamoeba trophozoites are larger, typically 12-25 µm, with pseudopods and a different nucleus structure than C. mesnili. Entamoeba species are amoebas without flagella. 💩 Traveler's diarrhea is often caused by Giardia intestinalis, a flagellate with a pear-shaped trophozoite of similar size (8-20 µm). However, G. intestinalis is bilaterally symmetrical with two nuclei.

Effusion fluids are classified as transudates or exudates. According to Light's criteria, all of the following applies to an exudate EXCEPT? A. Pleural fluid/serum protein ratio >0.5 B. Pleural fluid/serum lactate dehydrogenase (LDH) ratio >0.6% C. Pleural fluid lactate dehydrogenase (LDH) <2/3 the normal upper limit for serum D. Serum-ascites albumin gradient (SAGG) <1.1 g/dL

C. Pleural fluid lactate dehydrogenase (LDH) <2/3 the normal upper limit for serum ❌ Out of the listed criteria, "Pleural fluid lactate dehydrogenase (LDH) <2/3 the normal upper limit for serum" is the one NOT applicable to an exudate. To be classified as an exudate, the pleural effusion must meet one of the following criteria: Pleural fluid/serum LDH > 2/3 the upper limit for serum Pleural fluid/serum protein ratio >0.5% Pleural fluid/serum LDH ratio >0.6% Serum-ascites albumin gradient (SAGG) <1.1 g/dL

The scatterplot that is pictured represents results from a normal peripheral blood sample that was analyzed using flow cytometry. The cell that is indicated by the arrow on the right would fall into which of the circled areas? A. Population A B. Population B C. Population C D. The cell would not be detected in any of the three populations.

C. Population C Arrowed cell = segmented neutrophil! ➡️ X-axis = cell size, Y-axis = complexity/granularity. Neutrophils = intermediate size, more granular than lymphocytes or monocytes. 📏📊 Population A likely lymphocytes = smallest, lack granularity, near origin in size and complexity. 🚶‍♂️🔬 Population B likely monocytes = larger cells, less granularity. 🏃‍♂️🔬 Neutrophils detected by automated differential instruments using flow cytometry. 📊

The image is a Wright-Giemsa stained smear (1000x) of cerebrospinal fluid (CSF). What is the identification of the cells that are indicated by the arrows? A. Ependymal cells B. Atypical lymphocytes C. Presumptive malignant cells D. Immature white blood cells

C. Presumptive malignant cells 🔍 The cells with arrows ➡️ might be naughty cancer cells! 😬 To spot these troublemakers and their buddies as the bad guys, look for things like super big cells, cells squished together, a lot of nucleus compared to the gooey stuff around it (N/C ratio), uneven nuclei, weird nuclear walls, more than one nucleus in a cell, and empty spaces inside. 💢

Which of the following best describes the Westgard multirule 22S? A. Two control data points fall within the 95.5% confidence interval. B. One control data point falls outside +2 SD, and a second data point falls outside -3 SD. C. Two consecutive data points fall outside +2 SD or -2 SD limits. D. One data point from two days ago fell outside +2 SD, and today one data point for the same assay fell outside +2 SD.

C. Two consecutive data points fall outside +2 SD or -2 SD limits. Westgard multirule 22S: Two consecutive data points fall outside +2 SD or -2 SD limits. Violation occurs if both points in a day exceed the 2 SD limits or if one point exceeds 2 SD as seen in a previous run (same day) or previous day. 📊🚫🔍 If violated, reject the run—likely due to systematic error. ⚠️🚫🔬

Gram stains are performed on positive blood culture bottles. Each of the following responses correctly matches the organism with its description EXCEPT? A. Large, gram-positive rods with square ends occurring in short or long chains = Bacillus anthracis B. Small gram-negative coccobacillus or bacillus demonstrating bipolar staining = Yersinia pestis C. Very tiny, pale staining, gram-negative coccobacillus often arranging in pairs = Fusobacterium species D. Small, gram-negative coccobacilli that may stain very faintly or appear gram-positive due to retention of crystal violet stain; individual cells present = Brucella species

C. Very tiny, pale staining, gram-negative coccobacillus often arranging in pairs = Fusobacterium species Fusobacterium: Long, thin, filamentous gram-negative bacilli with tapered ends, arranging end to end. F. necrophorum may show irregular or pale staining with swollen ends. 🔬 Bacillus anthracis: Large, gram-positive rod with square or concave ends. Forms short chains in clinical specimens, longer chains in culture material. Oval spores may be central to sub-terminal. 🔍 Yersinia pestis: Gram-negative bacillus or coccobacillus. Forms short chains, resembles other Enterobacteriaceae. "Safety-pin" bipolar staining in blood culture. 🔬 Brucella species: Small, faintly staining gram-negative coccobacilli. May appear initially as gram-positive; counterstain with safranin improves visualization. 🔍👀

Which is the MOST accurate definition for an orthochromic normoblast or nucleated red blood cell (NRBC)? A) A cell with irregular lobulated or puckered shape containing residual RNA and mitochondria in the cytoplasm. B) A cell with a high nuclear-to-cytoplasmic ratio with a lacy, fine linear chromatin pattern. C) A cell with deeply basophilic cytoplasm, a perinuclear halo, and a wheel spoke chromatin pattern. D) A cell with a low nuclear-to-cytoplasmic ratio with pink cytoplasm and a heavily condensed chromatin pattern.

D) A cell with a low nuclear-to-cytoplasmic ratio with pink cytoplasm and a heavily condensed chromatin pattern.

All of the following are true in terms of platelet characteristics, EXCEPT? A) Produced in the bone marrow by megakaryocytes. B) Possess an inherent sticky property that aids in adhesion and aggregation. C) Have a lifespan of roughly 9-12 days. D) Are normally found circulating in their inactive, spiny form.

D) Are normally found circulating in their inactive, spiny form. Platelets 😊 are not normally found circulating in their inactive, spiny forms . Instead, they become spiny and sticky when they are activated in response to blood vessel damage. Platelets are produced in the bone marrow from megakaryocytes. Platelets do possess an inherent sticky property that helps them stick together and adhere to damaged blood vessels. Platelets have a lifespan of approximately 9-12 days before they are cleared from the circulation. ⏳

Storage lesion, or the biochemical changes in red blood cells during storage, will result in: A) Decreased hemoglobin B) Increased plasma sodium C) Decreased plasma potassium D) Decreased plasma pH

D) Decreased plasma pH Storage problem 📦 can make plasma pH go down ⬇️ as lactic acid levels rise ⬆️. Free hemoglobin levels increase as red blood cells burst 💥. Plasma sodium levels drop due to dilution from cell bursting 💦. 🍟 Plasma potassium levels rise because of cell bursting 🚀.

A D-test is performed on gram-positive cocci to determine inducible resistance to clindamycin when the isolate is sensitive to clindamycin and resistant to which antibiotic? A) Methicillin B) Vancomycin C) Cefoxitin D) Erythromycin

D) Erythromycin The right answer is erythromycin! 😊 When erythromycin tests show resistance but clindamycin is sensitive, we need to check if there's a hidden resistance to clindamycin. This check is called the "D-test." 📋 The D-test works like this: if there's a positive result, you'll see a 'D' shape around the clindamycin disk. This means there might be a resistance that's not easy to see at first. 🚫💊 The D-test is special because it's used specifically for finding this hidden resistance to macrolide antibiotics like erythromycin. None of the other medicines listed work the same way.

The following results were obtained on a patient with a history of mucocutaneous bleeding: PT: 12 seconds APTT: 26 seconds Bleeding Time: 18 minutes Platelet aggregation studies:ADP: abnormal responseThrombin: abnormal responseCollagen: abnormal responseRistocetin: normal response Which of the following does this patient seem to have? A) Bernard Soulier Syndrome B) Von Willebrand Disease C) Thrombotic Thrombocytopenic Purpura D) Glanzmann Thrombasthenia

D) Glanzmann Thrombasthenia Glanzmann Thrombasthenia is the correct diagnosis in this case. 😔 In Glanzmann Thrombasthenia, the patient will have normal PT and APTT results, but abnormal responses to all platelet aggregating agents except ristocetin. This disorder is characterized by a deficiency of the GP IIb/IIIa platelet receptor, which is responsible for binding fibrinogen to aid in platelet aggregation. 😔❌ Bernard Soulier Syndrome and Von Willebrand Disease are not the correct diagnoses because they would show an abnormal response to ristocetin, but a normal response to all other aggregating agents. 😔❌ Thrombotic Thrombocytopenic Purpura can be ruled out as it would display normal responses to all platelet aggregating agents. 😔❌

What is the unique colony morphology feature of Rhodotorula growing on Sabouraud Dextrose Agar (SDA)? A) Rugose (wrinkled) colonies B) Filamentous colonies C) Green/blue pigment D) Pink-red/orange pigment

D) Pink-red/orange pigment Rhodotorula is a yeast found in air, soil, lakes, ocean water, and dairy products. It may colonize immunocompromised individuals, with rising prevalence. Rhodotorula species are characterized by distinctive salmon color (pink-red/orange) pigmentation. In addition, this yeast has spherical to elongated budding yeast-like cells or blastoconidia and shows a small capsule on an India Ink preparation.

The ideal stool sample for parasitic examination is one that is freshly collected and submitted to the laboratory at: A) Refrigerator temperature (2°C) B) Incubation temperature (37°C) C) A temperature of -70°C D) Room temperature (approximately 22°C)

D) Room temperature (approximately 22°C) Room temperature is perfect for sending poop for parasite tests! 😊 Because the little parasites can break down fast, it's best to check watery poops within 30 minutes and mushy poops within 60 minutes after collecting them. 🕒 If you can't check them in time, use a special liquid to keep them fresh! 🌡️ Don't put your poops in the fridge or freezer or try to heat them up! ❄️🔥 Extreme temperatures can kill the parasites and mess up the test results. ❌ Never freeze and thaw your poop or put it in a warm place because the parasites can die quickly. 🚫

From the following list of parasites, identify which one has the smallest egg? A) Ascaris lumbricoides B) Paragonimus westermani C) Schistosoma mansoni D) Trichuris trichiura

D) Trichuris trichiura

Immunoglobulin M (IgM) is the characteristically overproduced gene product found in: A) Multiple myeloma B) Plasma Cell Myeloma C) Heavy chain disease D) Waldenström's disease

D) Waldenström's disease Waldenström's primary macroglobulinemia is considered to be a lymphoplasmacytic lymphoma as defined by World Health Organization classification system. It is a malignant lymphocyte-plasma cell proliferative disorder. Immunoglobulin M (IgM) is the characteristic overproduced gene product. IgG myeloma is the most common form of Multiple Myeloma. Four subtypes of IgG heavy chains are known to exist among patients with IgG myeloma (IgG1, IgG2, IgG3, IgG4). Plasma Cell Myeloma refers to Multiple Myeloma. IgG myeloma is the most common form of Multiple myeloma. Heavy Chain disease is characterized by the presence of monoclonal proteins composed of the heavy-chain portion of the immunoglobulin molecule. Alpha heavy-chain disease is the most common of the heavy-chain gammopathies.

HbA, the most common hemoglogin in adults is made with two a chains and two ß chains (a2ß2). What is the most common hemoglobin chain pair in fetal hemoglobin, HbF? A) ?2e2 B) a2e2 C) ?2?2 D) a2?2

D) a2?2 Fetal Hemoglobin HbF is like a 👶 superhero made of two 🅰️ chains and two ? chains (🅰️2?2). 😊 Hb Gower1 is like a cute 🐣 made of two ? chains and two 🅴 chains (?2🅴2) and is only found in embryos. Hb Gower2 is like a tiny 🚼 made of two 🅰️ chains and two 🅴 chains (🅰️2🅴2) and is only found in embryos. 🍼 Hb Portland is like a precious 💎 made of two ? chains and two ? chains (?2?2) and is only found in embryos.

Red cells units containing CPDA-1 as an anticoagulant-preservative may be stored for how long prior to transfusion? A. 5 days B. 15 days C. 25 days D. 35 days

D. 35 days Here we go! Red cell units with CPDA-1: cool at 1-6°C for 35 days. ❄️🏡 Other choices? No specific storage limits in current rules. CPD or CP2D units? Good for 21 days. 📆 Additive solutions like AS-1, AS-3, and AS-7? Boost storage to 42 days. 🚀📆 Easy, right? 🌟‍♂️

What is the correct identification for each egg illustrated? A. A: Hookworm egg B: Trichuris trichiura egg C: Enterobius vermicularis egg B. A: Ascaris lumbricoides egg B: Enterobius vermicularis egg C: Hookworm egg C. A: Diphyllobothrium latum egg B: Hookworm egg C: Trichuris trichiura egg D. A: Trichuris trichiura egg B: Hookworm egg C: Enterobius vermicularis egg

D. A: Trichuris trichiura egg B: Hookworm egg C: Enterobius vermicularis egg The correct answer is A: Trichuris trichiura egg 🐛 B: Hookworm egg C: Enterobius vermicularis egg 🐛. 🔍 Trichuris trichiura eggs have a thick shell with hyaline polar plugs. 🔍 Hookworm eggs have a thin shell that is broadly oval and contains four to eight cells when passed in the stool. 🔍 Enterobius vermicularis eggs have a colorless shell flattened on one side, with a c-shaped larva inside. 🔍 Ascaris lumbricoides eggs have a bumpy (mammillated) outer shell. 🔍 Diphyllobothrium latum eggs have an inconspicuous operculum with a small knob at the opposite end.

Red blood cells with a positive DAT cannot be tested accurately with blood typing reagents that require an indirect antiglobulin technique unless they have been treated with all of the following (to dissociate IgG from the RBC membrane) EXCEPT: A. Chloroquine diphosphate B. Ficin C. ZZAP D. Albumin

D. Albumin 📝 The correct answer is albumin. Albumin would not be effective in removing IgG bound to RBC's for further testing. 💉 RBCs with a positive DAT cannot be accurately tested with blood typing reagents that require an indirect antiglobulin technique unless treated with chloroquine diphosphate, ZZAP, or ficin to dissociate IgG from the RBC membrane.

Which of the following is NOT considered a characteristic of paroxysmal cold hemoglobinuria (PCH)? A. Patient population: children and young adults B. Pathogenesis: following viral infection C. Site of hemolysis: intravascular D. Autoantibody class: IgM

D. Autoantibody class: IgM 📚 PCH (paroxysmal cold hemoglobinuria) is a condition that has certain characteristics or factors associated with it. These include: The type of autoantibody involved is called IgG. 👶 PCH is commonly seen in children and young adults. 🚸 The condition is believed to develop after a viral infection. 🌡️ ❤️💥 Hemolysis, which means the breakdown of red blood cells, occurs inside the blood vessels. 🔴💥

The colonies seen growing on the surface of the blood agar plate shown in the upper photograph were recovered from a blood culture after 36 hours of aerobic incubation at 35° C. A Gram stain prepared from one of the colonies is shown in the lower photomicrograph. The most likely identification is: A. Clostridium species B. Listeria monocytogenes C. Corynebacterium striatum D. Bacillus circulans

D. Bacillus circulans 🔬 The right answer is Bacillus circulans! The colonies on the blood agar plate are gray, kind of see-through, spread out, and look buttery/mucoid. Without the Gram stain, you might think it's Gram-negative like Klebsiella pneumoniae or Pseudomonas aeruginosa. But, surprise! The Gram stain shows short, Gram-positive bacilli, and many cells have a spore (check out those blue arrows). 🔄 Bacillus circulans can grow in both air and no-air situations! 🌬️🚫 Clostridium species is a no-go. They're Gram-positive rods that only make spores when there's no air. 🚷 Listeria monocytogenes is a nope. It's a Gram-positive, non-spore-forming coccobacillus. Watch out for its beta-hemolytic action and don't confuse it with Group B streptococci! Corynebacterium striatum is a negative. It's a Gram-positive rod with a cool palisading arrangement, but no spores and doesn't do esculin. 🙅‍♂️

What is the vector for the transmission of Onchocerca volvulus? A. Mosquitoes B. Sandflies C. Reduviid D. Black Flies

D. Black Flies

All of the following red cell inclusions are identified in the frames of photographs, EXCEPT? A. Basophilic stippling B. Pappenheimer bodies C. Malaria parasite D. Cabot ring

D. Cabot ring No Cabot ring seen. It's a red-violet inclusion, oval or figure-eight, made of nuclear fragments or mitotic spindle fibers. 🚫🔬 Frame A: Pappenheimer bodies, tiny blue-staining bodies in Wright-smears (confirm with iron stain), often in pairs. Common in sideroblastic anemia. 👥🔵 Frame B: Erythrocyte with finely granular basophilic stippling (linked to autoimmune hemolytic anemias). 🔵 Frame C: Red blood cell inclusion, plasmodium ring form of Falciparum malaria, linked to recurrent fever. 💍 Frame D: Howell-Jolly bodies in erythrocytes after splenectomy. 🔴💔

Daily activities by microbiology personnel should be performed to ensure patients receive the best care. All of the following actions should be performed daily EXCEPT? A. Compare Gram stain reports with what grows in culture to ensure all organisms are recovered B. Check antimicrobial susceptibility reports to ensure correct drug/organism profiles C. Check susceptibility reports for multiple-drug-resistant organisms D. Check to ensure autoverification of results is working correctly

D. Check to ensure autoverification of results is working correctly Correct answer: Check autoverification of results to ensure it's working correctly! ✅ Validation needed once a year for accurate reporting. 📆💉 Incorrect answers: Daily checks needed! Compare Gram stain reports with culture to ensure all organisms recovered. 🔬🔍 Check antimicrobial susceptibility reports for correct drug/bug profiles. 💊 Check susceptibility reports for multiple-drug-resistant organisms. 🚫💊 Daily monitoring identifies and corrects errors before reaching physicians for quality care. 💉👨‍⚕️

Storage lesion, or the biochemical changes in red blood cells during storage, will result in: A. Decreased hemoglobin. B. Increased plasma sodium. C. Decreased plasma potassium. D. Decreased plasma pH.

D. Decreased plasma pH. Storage lesion ☠️ → lower plasma pH ⬇️, lactic acid ⬆️ in storage! Free hemoglobin ⬆️ when red blood cells burst! 💔 Plasma sodium ⬇️ from hemolysis dilution effect! 🌊 Plasma potassium ⬆️ due to unit hemolysis! 💥

Which of the following serum constituents is unstable if a blood specimen is left standing at room temperature for eight hours before centrifugation and processing? A. Cholesterol B. Triglyceride C. Creatinine D. Glucose

D. Glucose Glucose in blood drops over time due to red blood cell utilization. Glycolysis reduces levels by 5-7% per hour (5-10 mg/dL) at room temperature. To prevent changes, centrifuge and separate cells/serum within two hours of collection. ⏳💉

A unit of red blood cells collected on June 15, 2009, and frozen with glycerol at -80°C on June 20, 2009, will expire on what date? A. June 14, 2010 B. June 15, 2010 C. June 20, 2019 D. June 15, 2019

D. June 15, 2019 Let's break it down! The right answer is June 15, 2019; 10 years from the collecting date. 📅🔟 Frozen blood is a thing for rare or autologous units, and the FDA approves it for 10 years post-collection. Glycerol is the go-to, added within 6 days, and freeze time shouldn't pass 4 hours. ❄️⏳ When you need the blood, thaw it, and the expiration shifts to 24 hours from thawing. 🔄🕰️ So, the correct answer is 10 years from the collection date—June 15, 2019. 🎉📆 Easy, right? 🌟‍♂️

The distinctly large, spreading, mucoid colonies seen on blood agar in the upper left image, and the display of lactose fermentation on MacConkey agar in the upper right image provide for a presumptive organism identification. This species is most commonly recovered from respiratory specimens of patients with pneumonia. Observing the absence of motility, a weak reaction for urea, and strong reactions for citrate and Voges-Proskauer confirm the presumptive identification. From the multiple choices, select the name of the isolate presented here. A. Proteus mirabilis B. Edwardsiella tarda C. Citrobacter freundii D. Klebsiella pneumoniae

D. Klebsiella pneumoniae Correct response: Klebsiella pneumoniae! 👾🔬 Large, mucoid colonies with lactose fermentation on MacConkey agar. Weak urea reaction, strong citrate, and Voges-Proskauer reactions confirm. Non-motile, commonly found in pneumonia patients. 🏥💨 Incorrect responses: 🚫 Proteus mirabilis: Non-mucoid, swarming colonies, strong urea reaction, distinctive hydrogen sulfide (H2S) production. 🚫💨 Edwardsiella tarda: Non-mucoid, non-pigmented, non-lactose fermenter, negative citrate, and Voges-Proskauer reactions. Strong H2S production. 🚫💨 Citrobacter freundii: Smooth, slightly mucoid colonies, lactose production on Kligler Iron agar. Positive citrate, negative Voges-Proskauer. Many produce H2S. 🚫💨

An analytical method with a low detection limit would: A. Measure only what is being assayed B. Measure zero concentrations of analyte C. Perform accurately in the presence of interfering substances D. Measure low concentrations of analyte

D. Measure low concentrations of analyte Low detection limit: Detects low analyte concentrations. 🕵️‍♂️🔬 Specificity: Measures only what's being assayed. 🎯🔍 Analytical specificity: Measures a specific organism or substance in a sample. 🚫 Limit of blank: Measures a sample lacking the analyte. 📉🚫

The two nucleated cells in this peripheral blood smear image can be identified as (left image-right image): A. Myelocyte - lymphocyte B. Monocyte- nucleated red blood cell C. Monocyte - lymphocyte D. Myelocyte - nucleated red blood cell

D. Myelocyte - nucleated red blood cell 🔬 The cell on the left is an abnormal myelocyte with a large nucleus and blue cytoplasm. This immature cell is not normally found in healthy individuals. 🔬 🔬 The cell on the right is a nucleated red blood cell at the metarubricyte stage, which is also an immature erythroid stage not normally released. 🔴 ⚠️ Nucleated red blood cells can be mistaken for lymphocytes due to their condensed nucleus and bluish cytoplasm, but this cell's nucleus is smaller than that of a lymphocyte. 🔵 ⚠️ Although this myelocyte may resemble a monocyte due to its uneven nucleus, a monocyte has more abundant and bluer cytoplasm. These cells can be observed in conditions that disrupt the bone marrow, such as fibrosis or other invasive bone marrow disorders.

Various methods have been employed for the detection of Clostridioides difficile disease, which method is the new gold standard for detection? A. Culture on cycloserine-cefoxitin-fructose agar (CCFA) B. Cell cytotoxicity neutralization assay (CCNA) C. Enzyme immunoassays (EIA) detecting toxins D. Nucleic acid amplification tests (NAATs)

D. Nucleic acid amplification tests (NAATs) Nucleic acid amplification tests (NAATs) are becoming the new gold standard for detection. They determine the presence of toxin A and B genes in a stool sample. It is becoming the new gold standard since it does not need confirmation like other test methods. Cell cytotoxicity neutralization assays (CCNA) were considered for a long time the gold standard for Clostridioides difficile detection because they detect the toxins in the stool sample. However, the assay is labor-intensive and requires 48 of incubation for the cells to grow. The culture of stool on cycloserine-cefoxitin-fructose agar (CCFA) is very effective in detecting C. difficile, although it requires up to four days to isolate the organism. Isolates must also be subsequently tested for toxin production to prove their causal relationship to disease. Enzyme immunoassays (EIA) provide a more efficient and rapid means of diagnostic testing. Sensitivity of detection is enhanced by choosing a method that allows for the detection of both toxins A and B.

Which of the following is NOT required to be in a machine-readable format on a blood component label? A. ABO & Rh of the donor B. Product code C. Collection facility D. Outdate

D. Outdate Got it! The odd one out is the outdate! 📅✨ It can be handwritten but needs to be readable. 🖋️👁️ Now, according to 21 CFR 606.121, these must be machine-readable: 👨‍💻 A) Unique collection facility identifier B) Lot number linked to the donor C) Product code D) ABO and Rh of the donor Easy-peasy, right? 🌟‍♂️

While working at a blood bank laboratory, you hear chimes over the hospital loudspeaker system announcing the birth of a baby. Thirty minutes later, you receive a cord blood specimen that you identify as O positive. You previously received the mother's specimen and she was O negative with a negative antibody screen. What is the next action? A. Issue one vial of RhIg B. Perform a Kleihauer Betke stain C. Nothing - Mom is not at risk for anti-D D. Perform a fetal bleed screen

D. Perform a fetal bleed screen 👶🅰️🅱️ Because the baby is D+ and the mom is D- and not immunized to the D antigen, mom will need at least one 300 µg dose of RhIg. But first, we need to do a fetal bleed screen to check for FMH (fetal-maternal hemorrhage). If FMH is present, the screen will be positive, and a Kleihauer Betke stain is done. Some places use flow cytometry studies to quantify FMH. For FMH ≤ 30 mL, 1 vial of RhIg is given. For FMH > 30 mL, a calculation determines the number of RhIg vials needed.

In which developmental stage do red blood cells begin forming hemoglobin in amounts large enough to be visualized on a Wright-stained bone marrow aspirate smear? A. Reticulocyte B. Pronormoblast C. Basophilic normoblast D. Polychromatic normoblast

D. Polychromatic normoblast Hemoglobin starts in basophilic normoblast, but major synthesis kicks in with polychromatic normoblast! Polychromatic normoblast's cytoplasm on smear = gray-blue mix (pink from hemoglobin, blue from RNA)! 🎨💙 Basophilic normoblast's cytoplasm = deep, rich blue (ribosomes/RNA hide early hemoglobin)! 📘

Which of the following statements about hepatitis C virus (HCV) is true? A. There is vaccination against infection with HCV. B. The primary route of infection with HCV is airborne transmission. C. Patients infected with HCV will always have observable symptoms. D. The majority of individuals who are infected with HCV and develop antibodies in their serum (seroconvert) will develop a chronic infection and active liver disease.

D. The majority of individuals who are infected with HCV and develop antibodies in their serum (seroconvert) will develop a chronic infection and active liver disease. Most patients with antibodies 🛡️ will likely have ongoing liver issues due to Hepatitis C. 😔 Around 75-85% of people who get infected with Hepatitis C and have antibodies develop a long-term form of the disease. 🕒 Over time, about 70% of those with long-term infection will have liver problems. Unfortunately, there isn't a vaccine 🚫 to prevent Hepatitis C. It mainly spreads through blood 💉 and body fluids. 💧 People with chronic Hepatitis C may not feel sick for many years. 📅

The tiny colonies growing on chocolate agar after 3 days of incubation, as illustrated in the left plate in the upper photograph, were recovered from a skin abscess at the site of a contaminated needle injection. The colonies growing on Middlebrook 7H10 agar seen to the right in the image were larger, smooth, convex, and gray-white. Acid-fast stains were positive for the appearance of slender bacilli, consistent with one of the rapidly growing Mycobacteria. Reactions for nitrate reduction and iron uptake were negative. A distinctive characteristic was the antibiotic resistance to Ciprofloxacin (left upper strip) and Polymyxin B susceptibility (vertical strip) in the lower photograph. From these observations, select the identification of this isolate. a. Mycobacterium chelonae b. Mycobacterium fortuitum c. Mycobacterium gordonae d. Mycobacterium scrofulaceum

a. Mycobacterium chelonae Mycobacterium chelonae is the correct response. Characteristic is the rapid growth of gray-white smooth non-pigmented colonies both on chocolate agar and Middlebrook 7H10. The colony morphology and acid-fast staining characteristics do not distinguish between M. chelonae and M. fortuitum. One approach to making the identification of M. chelonae is by demonstrating resistance to Ciprofloxacin and susceptibility to Polymyxin B, susceptibility patterns opposite to those of M. fortuitum. Negative reactions for nitrate reduction and iron uptake can also be used to make the separation. Mycobcterium fortuitum colony growth is also rapid and differences in acid-fast staining appearance are not sufficient to separate M. fortuitum from M. chelonae. Differentiation M. fortuitum can be made by using a susceptibility test that demonstrates susceptibility to ciprofloxacin and resistance to Polymyxin B, in contrast to the opposite patterns of susceptibility for M. chelonae. Positive reactions for nitrate reduction and iron uptake also distinguish M. fortuitum. M. gordonae and M. scofulaceum colonies are slow-growing usually beyond 10 days that along with the yellow pigmentation of colonies both before and after exposure to environmental light (scotochromogens) serve to presumptively separate these Mycobacteria species from M. chelonae. Susceptibility testing is not required to make this separation.

A 43-year-old female presented to her doctor for a routine check-up. Her only complaint was that she had been experiencing watery stools that occasionally contained pus and blood. Physical examination revealed abdomen tenderness. A stool for ova and parasite was sent to the laboratory and these two suspicious forms were seen. The oblong form on the left measured 53 µm by 60 µm; the form on the right measured 45 µm by 37 µm. The parasite is MOST likely: a. Entamoeba histolytica b. Balantidium coli c. Dientamoeba fragilis d. Trichomonas vaginalis

b. Balantidium coli The correct answer is Balantidium coli. Balantidium coli is the most likely cause of balantidiasis in this patient, which is typically acquired by ingesting water and/or food contaminated with the infective cysts of the parasite. B. coli is characterized by its large cyst and trophozoite forms that are covered in cilia. Both stages of the parasite contain a kidney-bean-shaped macronucleus and a small, round micronucleus. Other parasites such as Entamoeba histolytica, Dientamoeba fragilis, and Trichomonas vaginalis are smaller in size than the measurements given and do not possess a large, kidney-bean-shaped macronucleus.

For an isolate of Escherichia coli, Klebsiella, or Proteus species testing positive for ESBL (Extended Spectrum Beta Lactamases), all of the following antibiotics should be reported as resistant except: a. Aztreonam b. Cefazolin c. Cefoxitin d. Ceftriaxone

c. Cefoxitin Organisms that test positive for ESBL production should be reported as resistant to all cephalosporin and penicillin antibiotics as well as aztreonam, regardless of MIC value. The cephamycins (cefoxitin and cefotetan) would be not reported as resistant as these are active antibiotics against ESBL-producing strains. Cefoxitin is a cephamycin and would have an interpretation reported based on the MIC value. It would not be changed to resistant for an ESBL-producing organism. Aztreonam should not be used for ESBL-producing strains and thus would all be reported as resistant, regardless of the MIC value. Cefazolin and ceftriaxone are both cephalosporin antibiotics and should not be used for ESBL-producing strains and thus would all be reported as resistant, regardless of the MIC value.