mlt part 2

A refrigerator used to store whole blood must be able to maintain a temperature in the ranges of: 0 - 4 degrees Celsius 2 - 4 degrees Celsius 2 - 8 degrees Celsius 1 - 6 degrees Celsius

1 - 6 degrees Celsius Feedback After collection all blood should be stored at 1 - 6oC, unless it is going to be used as a source of platelets.

Which of the following organisms is indole negative? Escherichia coli Klebsiella oxytoca Chryseobacterium indologenes Capnocytophaga canimorsus

Capnocytophaga canimorsus Feedback None of the Capnocytophaga species produce indole. Both Escherichia coli and Klebsiella oxytoca are strong indole producers. Chryseobacterium indologenes is a weak indole producer.

A tech is working with a small Gram-negative coccobacillus that may be Francisella tularensis. Which of the following tests could the tech use to rule out this organism? Catalase negative Beta-lactamase positive Urease negative Oxidase negative

Catalase negative Feedback Francisella tularensis is a catalase positive organism, thus if the tech is working with an organism that is catalase negative, they can rule out F. tularensis as an identification for the organism. Francisella tularensis is a Gram-negative coccobacillus that grows slowly and may need cysteine for optimal growth. Characteristics of the organism include beta-lactamase positive, urease negative, and oxidase negative.

Which lipid does not serve as a source of fuel, but can be converted to steroid hormones? Fatty acids Cholesterol Triglycerides Phospholipids

Cholesterol Feedback Cholesterol is an unsaturated steroid alcohol. Cholesterol is unique in that, unlike other lipids, it is not readily catabolized by most cells, and therefore, does not serve as a source of fuel. A small amount of cholesterol can also be converted by some tissue, such as the adrenal gland, testis, and ovary to steroid hormones such as glucocorticoids, mineralocorticoids, and estrogens.The majority of fatty acids are found as a constituent of triglycerides or phospholipids.Triglycerides contain three fatty acid molecules attached to one molecule of glycerol by ester bonds.Phospholipids are similar in structure to triglycerides except that they only have two esterified fatty acids. NEXT QUESTION

The following organism is an anaerobic organism that produces spores and a double-zone of beta-hemolysis. The correct answer is highlighted below Pseudomonas aeruginosa Clostridium perfringens Enterobacter aerogenes Cutibacterium (Propionibacterium) acnes

Clostridium perfringens Feedback Clostridium perfringens is an anaerobic organism that is known to cause gas gangrene, food poisoning, and necrotizing enteritis. The identification of this organism begins with the appearance of a Gram-positive, spore-forming bacillus that produces a double-zone of beta-hemolysis on blood agar. Pseudomonas aeruginosa is a Gram-negative bacillus that produces beta-hemolysis but it is not a double-zone of beta-hemolysis. This organism is frequently found in water sources including environmental and hospital environments. Many of the opportunistic infections are related to exposure to water such as the community-acquired 'swimmer's ear' (otitis externa) and hospital-acquired respiratory infections. Enterobacter aerogenes is a Gram-negative bacillus that produces no hemolysis on blood agar. It is an opportunistic pathogen associated frequently with contaminated medical devices such as respirators. Cutibacterium (Propionibacterium) acnes is an anaerobic Gram-positive bacillus but it does not produce any hemolysis on blood agar. Although it is known to cause acne and endocarditis, it is the most common anaerobic skin contaminate for blood cultures.

A Gram stain of drainage from an open wound revealed gram-positive bacilli with spores. This description would commonly rule out which one of the following organisms? (Choose the BEST response.) Clostridium perfringens Bacillus cereus Clostridium septicum Bacillus anthracis

Clostridium perfringens Feedback The presence of spores virtually rules out Clostridium perfringens. While the organism does produce spores, they are rarely seen in clinical infections. Bacillus cereus produces spores, but it does so only under aerobic and not under anaerobic conditions. Clostridium septicum produces spores as does B. anthracis. By elimination, Clostridium perfringens is the best answer.

The serum medium and methylene blue stain originally described by Loeffler are both helpful in the identification of: Bordetella pertussis Corynebacterium diphtheriae Streptobacillus moniliformis Gardnerella vaginalis

Corynebacterium diphtheriae Feedback The combination of Loeffler's serum medium and Loeffler's methylene blue stain has been used for the recovery and presumptive identification of Corynebacterium diphtheriae. In the methylene blue stain, the bacterial cells of C. diphtheriae appear mottled from the uptake of dye by metachromatic granules. The identification must be confirmed by demonstrating the presence of diphtheria toxin. Potato starch and glycerol are required in culture media for the recovery of B. pertussis; the bacterial cells are not metachromatic. Serum supplements are needed for the recovery of Streptobacillus moniliformis; however, the bacterial cells do not stain metachromatic. Human blood, not serum, is required for the optimum recovery of Gardnerella vaginalis. NEXT QUESTION

The photomicrograph is a representative field from a peripheral blood smear. Which of the following MCV values correlates best with the peripheral blood picture? The correct answer is highlighted below 68 fL 82 fL 105 fL 149 fL

105 Feedback Most of the cells observed in the peripheral blood smear are slightly larger than normal red blood cells. This is based on the fact that the majority of the red blood cells are larger than the nucleus of the small lymphocyte in the field, which can be used as a reference for the normal size of a red blood cell. These red blood cells are classified as macrocytes. The reference interval for MCV is 80-100 fL. An MCV value below 80 fL correlates with a finding of microcytes; an MCV value above 100 fL correlates with a finding of macrocytes. 105 fL is the best option since the red blood cells are only slightly larger than the nucleus of the small lymphocyte. An MCV of 68 fL correlates with a finding of microcytes. An MCV of 82 fL correlates with a finding of normocytes. An MCV of 149 fL correlates with very large macrocytes, much larger than those seen in this peripheral blood smear.

All of the statements below regarding amylase and lipase in pancreatitis are true EXCEPT: Amylase and lipase are as predictive in chronic pancreatitis as they are in acute pancreatitis. Diagnosis sensitivity is increased by assaying both amylase and lipase. Urinary amylase: creatinine ratio is the most sensitive test for acute pancreatitis. Serum lipase peaks at 24 hours after an episode of acute pancreatitis and remains high for 7-8 days.

Amylase and lipase are as predictive in chronic pancreatitis as they are in acute pancreatitis. Feedback Serum amylase and lipase levels may be slightly elevated in chronic pancreatitis, but not diagnostic enough to predict chronic pancreatitis; whereas high levels are found only during acute pancreatitis episodes. In the later stages of chronic pancreatitis, normal to decreased levels of amylase and lipase are caused by the gradual inability of the pancreas to secrete the enzymes.

A 27-year-old female presents to her physician after suffering a spontaneous abortion. Though rare, which antibody may be the etiological agent? Anti-P1 Anti-P Anti-PP1Pk Anti-P2

Anti-P Feedback Individuals with the P1k phenotype only express the P and Pk antigens, so they may form an anti-P antibody. This antibody is clinically significant as it can cause spontaneous abortion, but it is a rare phenotype to possess. The Anti-P1 antibody is a cold-reacting antibody that is not clinically significant. Null-type individuals have the P phenotype. The corresponding Anti-PP1Pk can be clinically significant, but it causes hemolysis. The P1 and P2 phenotypes are similar to A1 and A2. Anti-P2 does not naturally exist. NEXT QUESTION

The infectious diseases listed below are listed with the most commonly associated bacterium, EXCEPT: Haemophilus aegyptius - "Pink eye" Pseudomonas aeruginosa - "Swimmer's ear" Aspergillus niger - "Black lung" Burkholderia pseudomallei - "Meliodosis"

Aspergillus niger - "Black lung" Feedback The correct answer is Aspergillus niger - "Black lung". Aspergillus niger is actually the most common fungal cause of "swimmer's ear". "Black lung" is actually caused by long term exposure to coal dust, not a microorganism. "Pinkeye" is a general term for acute infection of the conjunctiva, but classically has been attributed to Haemophilus aegyptius, thought by most microbiologists to be a variant of Haemophilus influenzae. Pseudomonas aeruginosa is the most common bacterial cause of "swimmer's ear". This occurs when water is retained in the outer ear canal, giving the perfect habitat for bacteria (or fungi) to grow. Melioidosis is a glanders-like infection (fever, malaise, cutaneous cellulitis, ulceration, and abscess formation) that affects animals and humans. It is caused by the bacterium, Burkholderia pseudomallei, which is endemic in regions of Thailand, Vietnam, and Southeast Asia.

When should you first refer to a chemical's label? Before moving or opening the chemical Before disposing of the chemical After a spill After accidentally ingesting the chemical

Before moving or opening the chemical Feedback The correct answer is before moving or opening the chemical. You should always read a chemical's label BEFORE working with the chemical to ensure the proper precautions are being taken. It is also in the best interest of laboratory professionals to learn as much as possible about the chemicals they work with in order to decrease the risk of improper handling, storage, usage, contamination, etc. NEXT QUESTION

A person who lived in the United Kingdom between the years of 1980 and 1996 for 3 or more months is indefinitely deferred from donating blood or blood products based on an increased risk of which of the following? Malaria Leishmaniasis Creutzfeldt-Jakob disease (CJD) and/or variant Creutzfeldt-Jakob disease (vCJD) Chagas disease

Creutzfeldt-Jakob disease (CJD) and/or variant Creutzfeldt-Jakob disease (vCJD) Feedback The correct answer is CJD and/or vCJD. If a potential blood donor spent more than 3 months in the United Kingdom between 1980 and 1996, or 5 or more years in France from 1980 to the present, they are indefinitely deferred due to an increased risk of CJD and/or vCJD. If they have ever been diagnosed with CJD or vCJD, they are permanently deferred. Persons with malaria or who have been infected with malaria are deferred for a period of 3 years after they are asymptomatic. The United Kingdom (UK) is not a malaria-endemic area and traveling to the UK in and of itself, would not be cause for deferral based on a potential malaria infection. Traveling to an area that is endemic for Leishmaniasis may be cause for a 12-month deferral from the time you left the area. The UK is not an Leishmaniasis endemic area. It is endemic in tropical and subtropical areas of the Middle East, Mediterranean, Africa, Central and South America, and Asia. Chagas disease is endemic in parts of Central and South America and Mexico. The UK is not an endemic area of Chagas disease. All potential donors are tested one time for Trypanosoma cruzi, the causative agent of Chagas disease. If the potential donor tests nonreactive for Chagas disease, the donor doesn't need to be retested. The rational for this is that most persons with Chagas disease have a chronic infection that was acquired while in a endemic area. FINAL SCORE

Direct examination of treponemes can be performed by: Light microscopy examination Darkfield microscopy examination VDRL testing Rapid Plasmin Reagin (RPR) testing

Darkfield microscopy examination Feedback Darkfield microscopy allows for direct observation of spirochetes from an active syphilitic lesion. It is the test of choice for examining symptomatic patients with primary syphilis. A darkfield examination is also suggested for immediate results in cases of secondary syphilis.The traditional logarithm for syphilis testing of suspected patients with syphilis begins with observations of classic lesions present, suggestive sexually transmitted infection history, and current sexually transmitted disease. Non-treponemal testing such as the Rapid Plasmin Reagin (RPR) is the next step. A reverse sequence testing algorithm begins with the same patient observations but the next step is to perform treponemal testing by chemiluminescence immunoassay or enzyme immunoassay.Light microscopy examination is not effective in the detection of spirochetes. Darkfield or fluorescent microscopy techniques are required for direct observation of spirochetes.The VDRL assay is a flocculation test that measures IgM and IgG antibodies to lipoidal material released from damaged host cells, to lipoprotein-like material, and possibly to cardiolipin released from the treponemes. Without some other evidence for the diagnosis of syphilis, a reactive nontreponemal test does not confirm T. pallidum, infection. Antilipoidal antibodies are antibodies that are not only produced as a consequence of syphilis and other treponemal diseases but also may be produced in response to nontreponemal diseases of an acute or chronic nature in which tissue damage occurs.Rapid Plasmin Reagin (RPR) testing is a non-treponemal testing method. Traditionally, it is the next step in serological assessment. The RPR is the most widely used assay to determine the presence of reagin, an antibody formed against cardiolipin, a lipid remnant of damaged cells, cholesterol, and lecithin, is used to detect the nontreponemal regain antibodies. NEXT QUESTION

Which one of these Gram-positive species has a high incidence of vancomycin resistance? Aerococcus species Enterococcus faecium Group D streptococci Streptococcus pyogenes

Enterococcus faecium Feedback Vancomycin-resistance in Enterococcus faecium is close to 90% in blood cultures in the U.S. In addition to Enterococcus faecium, E. faecalis is also isolated in nosocomial infections such as UTI or bacteremia. Leuconostoc and Pediococcus are other Gram-positive cocci that demonstrate resistance to vancomycin.Aerococcus species, Group D streptococci, and Streptococcus pyogenes are usually susceptible to vancomycin. Aerococcus is an opportunistic pathogen causing infection similar to other gram-positive cocci. Group D streptococci are part of the viridans group found as normal flora but may cause infections such as bacteremia and endocarditis. Streptococcus pyogenes is found as normal flora existing on the skin and in the oropharynx but may cause serious infections such as pharyngitis, necrotizing fasciitis, TSS, and rheumatic fever. NEXT QUESTION

Which of the following organisms is Gram-positive? Pasteurella Erysipelothrix Aeromonas Fusobacterium.

Erysipelothrix Feedback Erysipelothrix is the only choice given that is Gram-positive. Erysipelothrix is thin Gram-positive bacilli. Pasteurella is a small, Gram-negative bacillus with bipolar staining. Aeromonas is also a Gram-negative bacillus. Fusobacterium is Gram-negative bacilli with tapered or pointed ends. FINAL SCORE

The prothrombin time test will detect deficiencies in which pathways? Extrinsic and intrinsic pathways Extrinsic and common pathways Intrinsic pathway and common pathways Intrinsic pathway only

Extrinsic and common pathways Feedback The prothrombin time, or PT, will detect coagulation factor deficiencies in the common and extrinsic pathways. These factors include I, II, V, X (common pathway factors), and factor VII (extrinsic factor). The activated partial thromboplastin, or aPTTT, detects factors in the intrinsic and common pathways. The intrinsic factors include Factors XII, XI, IX, and VIII. Neither test reflects the intrinsic pathway alone since the common pathway follows it and is necessary for fibrin clot formation.

A variety of additives are used in blood collection tubes. Which of the following additives is used to separate serum or plasma from the cells? The correct answer is highlighted below EDTA Sodium fluoride Sodium heparin Gel

Gel Feedback The gel in the tube is used to form a barrier between plasma/serum and blood cells upon centrifugation. EDTA prevents blood from clotting by binding calcium which in turn inhibits the coagulation cascade. EDTA is found in the lavender, pink, white, royal blue, and tan top tubes. Sodium fluoride is found in gray top tubes and its purpose is to inhibit glycolysis (metabolism of glucose by red blood cells). Sodium heparin is an additive used to prevent clotting by inhibiting thrombin and thromboplastin. It is found in green and light green tubes.

A patient presents to his family doctor with respiratory issues. He has a history of being a heavy smoker for more than 20 years, so the physician orders a BAL cell count with differential. Which of the following cells would most closely correlate with the patient's medical history? The correct answer is highlighted below Macrophages with phagocytized red blood cells Macrophages with phagocytized bacteria Macrophages with purple/black inclusions Macrophages without any inclusions

Macrophages with purple/black inclusions Feedback Macrophages containing purple/black inclusions would most closely correlate with the patient's medical history of being a heavy smoker for more than 20 years. These cells contain hemosiderin and are also known as siderophages. Macrophages with phagocytized red blood cells would correlate with the normal removal of old red blood cells from circulation by the macrophages in the spleen. Macrophages with phagocytized bacteria would correlate with a bacterial infection. Macrophages without any inclusions would be a normal presentation on the differential and would not indicate a disease state. NEXT QUESTION

When serotyping Salmonella typhi, false-negative reactions can occur when testing. For example, a Salmonella typhi isolate tested Vi antiserum positive and O antiserum negative. What should be done next? Report out results as they are correct Heat specimen and repeat O antiserum test Heat specimen and repeat Vi antiserum test Check the antiserum expiration date

Heat specimen and repeat O antiserum test Feedback Heat specimen and repeat O antiserum test is correct because Salmonella typhi Vi capsular polysaccharide can mask the agglutination reaction of the O antigens and antiserum. If the antiserum Vi is positive and the O antiserum is negative, the Salmonella isolate should be heated for 15 minutes to remove the capsule. After cooling, the specimen should be retested using O antiserum. A presumptive identification can be made based on the positive reactions of Vi and O antigens, negative urease production, positive H2S production, and lack of lactose fermentation. Report out results as they are correct is incorrect because the Vi capsular antigen can mask the O somatic antigen in serotyping. Therefore, before results can be reported the specimen must be heated and the O somatic antigen must be retested, if a negative reaction occurred. Heat specimen and repeat Vi antiserum test is incorrect because this refers to the O somatic antigen serotyping as the Vi capsular antigen can mask the O somatic antigen. Check antiserum expiration date is incorrect even though this is a troubleshooting step. Antisera issues will be detected when controls are performed before each day of use. NEXT QUESTION

Identify the urine sediment element indicated by the arrow in the illustration: Mucus thread Cylindroid Hyaline cast Waxy cast

Hyaline cast Feedback Hyaline casts generally appear colorless, homogeneous, and transparent with rounded ends. They can also be seen as a result of dehydration, after diuretic therapy, in renal disease, and transiently as a result of exercise. A mucus thread can be seen under phase-contrast or interference contrast microscopy and can resemble delicate ribbon strands that are generally transparent. They are normal in small numbers in the urine. A cylindroid resembles a cast, with the exception that one end tapers out. They are considered to have the same significance as casts. Waxy casts are yellow, gray, or colorless and very refractive. They resemble short broad casts with broken ends and cracked edges.

A stool specimen can be suspected of harboring Vibrio cholerae if it possesses which of the following characteristics? If the stool is well-formed and shows blood streaks. If the stool is soft, dark, and positive for occult blood. If the stool contains a high concentration of segmented neutrophils. If the stool is watery with a high pH and flecks of mucus.

If the stool is watery with a high pH and flecks of mucus. Feedback Diarrhea caused by V. cholera is watery and contains large concentrations of sodium, bicarbonate, and other electrolytes, producing an alkaline pH. The diarrhea is caused by the action of cholera toxin on the intestinal epithelial cells, with the end result of stimulating adenyl cyclase (cyclic AMP), which in turn inhibits the reabsorption of sodium across the brush border membrane and stimulates the excretion of bicarbonate and potassium into the bowel lumen. A stool specimen comprised of primarily fluid and flecks of mucous (known as rice water stools) is a distinctive feature when cholera toxin activity is present. In the absence of mucosal invasion by the bacteria, blood or neutrophils are not found in the stool specimen. FINAL SCORE

Spectrophotometric absorbance is related to % transmittance in what way: Inversely and arithmetically Inversely and logarithmically Directly and arithmetically Directly and logarithmically

Inversely and logarithmically Feedback Particles in a solution absorb certain wavelengths while they transmit others. The color red we see in a solution, for example, appears red to the human eye because the particles in the solution absorb all the wavelengths except red, which is transmitted and seen. As the concentration of particles in a solution increases, the amount of absorbed light increases, while the percentage of light transmitted decreases. Absorbance (A) is the inverse log of transmitted (T) light. A = log(1/T) or A = -log(T)

This illustration demonstrates a non-pathogenic amoeba that measures 5-20 µm, contains a large glycogen mass, and a single nucleus with a large karyosome and no peripheral chromatin. What is this parasite? Entamoeba hartmanni cyst Entamoeba coli cyst Endolimax nana cyst Iodamoeba bütschlii cyst

Iodamoeba bütschlii cyst Feedback The cysts of Iodamoeba bütschlii may be readily identified by their size (approximately 12 µm) and by the presence of a well-defined glycogen mass. Furthermore, the large karyosome and absence of peripheral chromatin that constitutes the single nucleus help to distinguish them from the other amebic cysts. This organism is non-pathogenic. Entamoeba hartmanni cyst is a smaller version of Entamoeba histolytica. It is 5-10 µm with 1-4 nuclei, a small centrally located karyosome, and possibly a round, blunt, chromatoid body. It is non-pathogenic. Entamoeba coli cysts are typically 10-35 µm, may contain 5-8 visible nuclei each with a small eccentric karyosome. If the chromatoid body is visible, it typically has splintered ends. This organism is non-pathogenic. Endolimax nana cysts measure 5-10 µm, may contain 2-4 visible nuclei each with a small eccentric or centrally located slightly larger karyosome. There is typically no visible peripheral chromatin.

What is a LIS in a hospital setting? Laboratory Immunology System Laboratory Intellectual System Laboratory Informative Subsets Laboratory Information System

Laboratory Information System Feedback The Laboratory Information System, or LIS, is a combination of computer hardware and software designed to interface with instruments, transfer data, allow patient record recalls, store quality control data, and much more.

Normal adult CSF may have 0-5 white blood cells (WBCs)/µL. Which of the following cell types account for 60-100% of these WBCs? Neutrophils Lymphocytes Monocytes Eosinophils

Lymphocytes Feedback Typically, majority of cells seen in a normal adult CSF specimen are lymphocytes and monocytes (70:30 ratio). This ratio is reversed in children.

Albumin levels are can be a good gauge for chronic protein deficiency. Which of the following terms describes inadequate protein and caloric intake? Kwashiorkor Marasmus Albuminemia Hypoproteinism

Marasmus Feedback The correct answer is marasmus. Marasmus is a nutritional disease as a result of calorie deprivation. This includes an insufficient amount of protein.Kwashiorkor is a nutritional disease resulting from protein deprivation. In some cases caloric intake can be adequate or even excessive.Albuminemia is not a term that is commonly used. It would only point to album and not other proteins and would not describe an insufficient caloric intake.Hypoproteinism is not a term that is used. Hypoproteinemia is a term that can be used to describe low levels of protein in the blood, but would not necessarily be used to describe a low caloric intake. NEXT QUESTION

Which of the following statements is TRUE regarding "protected health information" (PHI)? PHI only includes information that is transmitted on paper or electronically; it does not include oral information. A patient's past physical or mental health conditions are not considered PHI. PHI includes information that is transmitted in any form (orally, on paper, or electronically). None of the above

PHI includes information that is transmitted in any form (orally, on paper, or electronically). Feedback PHI includes information that is transmitted in any form (orally, on paper, or electronically). It includes a patient's past, present, and future physical or mental health conditions.

Which of the following tumor markers is associated with the prostate? CEA PSA Alpha-fetoprotein Beta HCG

PSA Feedback PSA, or prostate specific antigen = Prostate CEA, or Carcinoembryonic Antigen = Colon beta hCG, or Human chorionic gonadotropin = Testicles AFP, or Alpha-fetoprotein = Liver NEXT QUESTION

This image was taken from a patient suffering from severe organism-related anemia. Which organism could be responsible for this patient's anemia? Plasmodium sp. Ehrlichia sp. Bartonella sp. Escherichia sp.

Plasmodium sp. Feedback The correct answer is Plasmodium sp. Since the image depicts intracellular ring-shaped red blood cell inclusions, the only choice that matches this morphology is Plasmodium species. Ehrlichia species is associated with an intracellular white blood cell parasitic inclusion. Bartonella species are associated with intracellular organisms inside red blood cells in single, chained, or paired morphologies. Escherichia species are gram-negative bacterial rods that are typically extracellular and can cause sepsis but are not generally associated with anemia. NEXT QUESTION

Bacterial contamination is MOST likely in which of the following blood products? Packed red blood cells Frozen red blood cells Platelets Fresh frozen plasma Feedback

Platelets Feedback The correct answer is platelets. Bacterial contamination of platelets is most likely because they are stored at room temperature. The estimated rate of bacterial contamination in platelets is around 10%. Bacterial contamination is possible in packed red blood cells stored in the refrigerator, but the estimated rate of bacterial contamination is only around 0.2% Frozen red blood cells are not likely to have bacterial contamination. Fresh frozen plasma is not likely to have bacterial contamination. FINAL SCORE

In this photomicrograph, several dematiaceous hyphae with long, flask-shaped, tapered phialides that have flat saucer-like terminus are seen (arrow). This feature is most characteristic of which of the following fungal species? Phialophora verrucosa Pleurostomophora richardsiae Exophiala jeanselmei Scopulariopsis brumptii

Pleurostomophora richardsiae Feedback Pleurostomophora richardsiae (formerly Phialophora richardsiae) is the correct answer because this fungal species produces phialides with distinct flattened or saucer-like collarettes. Phialophora verrucosa is incorrect because this fungal species produces deeper, more cup or flask-shaped phialides. Exophiala jeanselmei is incorrect because this fungal species produces long, slender, tapered phialides that may appear roughened at the tip where the rings or annelids have formed. Scopulariopsis brumptii is incorrect because this fungal species produces lemon-shaped, flat, truncated base phialides, rather than the open phialides seen with these other species. Often resembles Penicillium at first glance. NEXT QUESTION

Why is Rh immune globulin (RhIg) administered within 72 hours of delivery to an Rh negative mother if the newborn is found to be D-positive or weak-D positive? Prevent future children from producing antibodies Prevent fetal cells from initially sensitizing the mother Prevent antibody response in a previously sensitized mother Neutralize any natural maternal antibodies present

Prevent fetal cells from initially sensitizing the mother Feedback The production of IgG antibodies (particularly anti-D) can have threatening consequences for the fetus. RhIg is available and prevents alloimmunization in D negative mothers exposed to D positive red cells. RhIg suppresses the immune response after exposure to D positive fetal cells and prevents the mother from producing anti-D. All Rh-negative women should receive at least one full dose of RhIg at 28 weeks gestation and another full dose after birth (within 72 hours of delivery, assuming that the newborn is found to be D-positive or weak D-positive). This situation develops from the fetal cells having the D antigen and not from fetal antibodies. Once a woman is alloimmunized and produces antibodies, the condition cannot be reversed. Anti-D is not considered a natural antibody.

Vaccines can be divided into the following non-experimental types with the exception of: Live, attenuated Inactivated Toxoid Recombinant vector

Recombinant vector Feedback Recombinant vector vaccines are experimental vaccines similar to DNA vaccines, but they use an attenuated virus or bacterium to introduce microbial DNA to cells of the human body. Vector refers to the virus or bacterium used as the carrier. Researchers are working on recombinant vector vaccines for HIV, rabies, and measles. Live attenuated vaccines contain a version of the living microorganisms that have been weakened in the laboratory to prevent the organism from causing disease. A live attenuated vaccine is the closest thing to exposure to a natural infection. Inactivated vaccines are manufactured by killing an infectious microbe with chemicals, heat, or radiation. This type of vaccine is more stable and safer than live vaccines. The disadvantage of inactivated vaccines is that they stimulate a weaker immune system response than live vaccines. Usually, a weaker response necessitates additional doses or booster shots to maintain immunity, e.g., influenza vaccination. Toxoid vaccines are used when a bacterial toxin is the main cause of illness. Toxins can be inactivated. Such "detoxified" toxins called toxoids are safe for use as vaccines. A toxoid vaccine containing a harmless toxoid stimulates the immune system to produce antibodies that react to and block the toxin. Vaccines against diptheria and tetanus are examples of toxoid vaccines.

All of the following vacutainer tube colors are correctly paired up with the anticoagulant found in them EXCEPT? Light blue - Sodium Citrate Lavender - EDTA Gray - Potassium oxalate Red - Silica

Red - Silica Feedback While some plastic red top tubes contain silica, silica is not an anticoagulant. It is included in plastic tubes to aid in facilitating the clotting process, not preventing it.All the other tube colors and anticoagulants are correctly paired up with one another.

The type of sporulation of the dematiaceous mold that is illustrated in this photomicrograph is called: Acrotheca Rhinocladiella Birds on a fence Acropetal

Rhinocladiella Feedback Rhinocladiella is the correct answer because production of single conidia in succession both laterally and around the tip of a straight phialide is called the rhinocladiella type of sporulation, characteristic of Fonsecaea pedrosoi. Acrotheca type sporulation is incorrect because this type of sporulation is characterized by the production of short chains of elliptical conidia in a circular arrangement from the tips of branching phialides. Birds on a fence is incorrect because this type of arrangement of microconidia is characteristic of Trichophyton rubrum. This type of sporulation is somewhat reminiscent of the rhinocladiella type sporulation except that the conidia are more loosely held and alternate more from one side of the hyphae to the other. (Trichophyton rubrum is a hyaline rather than a dematiaceous fungus.) Acropetal in incorrect because this term refers to a type of sporulation where chains of conidia are formed with each new daughter cell produced from the previous one, leaving the oldest cell at the base of the chain. This type of sporulation is characteristic of Aspergillus species and Penicillium species. NEXT QUESTION

Which of the following describes gastrin's role in digestion? Stimulates gastric acid-HCl secretion Stimulates secretion of a base to lower the stomach's pH Is secreted when the gastric fluid pH is low to buffer fluid Inhibits the secretion of intrinsic factor

Stimulates gastric acid-HCl secretion Feedback Gastrin is secreted by the gastrointestinal mucosa cells in response to mechanical stress or high pH, both of which are produced by the presence of food in the stomach. Gastrin stimulates the stomach parietal cells to produce gastric hydrochloric acid. NEXT QUESTION

Which of the following best defines specific gravity: Weight Volume Density The density of a solution compared to the density of water

The density of a solution compared to the density of water Feedback Specific gravity is the ratio of the mass of a solution to the mass of an equal volume of water. Urine specific gravity increases as ionic concentration increases. If there were no solutes present, the specific gravity of urine would be 1.000, which is the same as pure water. Since all urine has some solutes present, a urine SG of 1.000 is not really possible. The upper limit of the test pad on a chemical reagent strip, which is typically 1.035, indicates concentrated urine, one with many solutes with a smaller amount of water. NEXT QUESTION

A laboratory test flags a critical result. The technologist repeats the test, and it again flags as a critical result. Which of these scenarios correctly describes all the actions that need to be taken after this occurs? The technologist immediately releases the result. The technologist phones the clinical person handling the patient's care (caregiver) and reports the critical test result. The technologist phones the patient's caregiver, reports the critical result, documents his placement of the call, who was notified, time, and date of notification. The technologist phones the patient's caregiver, reports the result, and asks the caregiver to read back the information; documents his placement of the call, who was notified, time, and date of notification.

The technologist phones the patient's caregiver, reports the result, and asks the caregiver to read back the information; documents his placement of the call, who was notified, time, and date of notification. Feedback Critical laboratory test results that are given over the phone must only be given to a clinical person (person in charge of the patient's care). The person who receives the result should be asked to read back the information that is given to verify that it was heard correctly. The person who reported and called the result, the person who was notified, and the date and time of notification should be documented along with the test result. NEXT QUESTION

Brucella suis and Salmonella typhi can commonly infect the spleen, liver, and bone marrow. Which of the following reasons allows these two organisms to cause a systemic infection? They both can only infect the spleen, liver, or bone marrow They are ingested by eosinophils and the eosinophils take them to the spleen, liver, and bone marrow They are both ingested by monocytes and/or macrophages within the spleen, liver, and bone marrow They both have the capability to suppress interleukins of the immune system, which will allow the spread of the organisms throughout the bloodstream causing infections of the spleen, liver, and bone marrow

They are both ingested by monocytes and/or macrophages within the spleen, liver, and bone marrow Feedback They are both ingested by monocytes and/or macrophages within the spleen, liver, and bone marrow is the correct answer because monocytes and macrophages will phagocytize infected neutrophils within the bloodstream as they enter the spleen, liver, and bone marrow. Monocytes/Macrophages are part of the reticuloendothelial system to remove debris and dead or dying cells out of the bloodstream. Since these organisms can remain viable not only in neutrophils but in monocytes and macrophages, granulomas can develop in these organs causing infection. They both can only infect the spleen, liver, or bone marrow is incorrect because Brucella suis can cause wound infections and has been linked to endocarditis. Salmonella typhi is a gastrointestinal pathogen that causes diarrhea and has been linked to infection of the gall bladder leading to carrier status. They are ingested by eosinophils and the eosinophils take them to the spleen, liver, and bone marrow is incorrect because eosinophils do not ingest the organisms. The neutrophils are the cells that do the initial phagocytizing and then the monocytes/macrophages will remove the infected cells as they enter the spleen, liver, and bone marrow. They both have the capability to suppress interleukins of the immune system, which will allow the spread of the organisms throughout the bloodstream causing infections of the spleen, liver, and bone marrow is incorrect because they do not suppress interleukins within the immune system. Brucella suis has the capability to interfere with the phagosome-lysosome fusion within macrophages and Salmonella typhi has many virulent factors that allow the organism to replicate and survive within the macrophages. NEXT QUESTION

This parasite is typically found in striated muscle and is responsible for which one of the following conditions? Trichinosis Elephantiasis River blindness East African sleeping sickness

Trichinosis Feedback The correct answer is trichinosis. The organism pictured is Trichinella spiralis. This organism is an intestinal-tissue nematode whose larvae encyst by coiling in muscle tissue. Humans are an accidental host that becomes infected when encysted larvae are ingested through poorly cooked pork. Elephantiasis can be caused by three different microfilariae: Wucheria bancrofti, Brugia malayi, or Loa loa. All three are introduced to humans by larvae that are transmitted by the bite of an infected insect. River blindness is caused by Onchocerca volvulus. It is called such because of the ocular involvement that leads to varying degrees of loss of sight. Microfilariae are found in the nodule following the bite of a fly and may cause localized infection or wander to infect other tissues, including the eye. East African sleeping sickness is caused by Trypanosoma brucei subspecies rhodesiense. It is transmitted to humans by the bite of an infected tsetse fly transmitting epimastigotes.

Which of the following urine chemical reagent strip tests is based on the Ehrlich-aldehyde reaction? pH Protein Glucose Urobilinogen

Urobilinogen Feedback The urobilinogen urine chemical reagent strip test is based on the Ehrlich-aldehyde reaction in which urobilinogen reacts with p-dimethylaminobezaldehyde (Ehrlich reagent). In this test, a pink-red color forms in proportion to the amount of urobilinogen present. NEXT QUESTION

Generally speaking, infant RBCs demonstrate the presence of the ____ antigen, which gradually decreases as one ages. Conversely, the ____ phenotype is not expressed at birth, but the amount of this antigen increases as one ages. M; N K; k i; I M; K

i; I Feedback From birth onwards - the "i" antigen slowly decreases on the RBC surface, while the "I" antigen increases reciprocally. It's a unique characteristic of this particular pair, with no other pair of common blood bank relevant antigens demonstrating such a trait. In practice, while auto anti-i is rarely seen, when suspected, one could simply react the patient's serum with cord RBCs, expecting to see a strong reaction. Meanwhile, reacting the patient's serum with adult RBCs would yield a weak or no reaction. Antigens in the MNS and Kell systems are present at birth. The number of antigens expressed on red cells within these systems does not vary based on age. NEXT QUESTION