MLS ASCP Study Questions - 1
Which of the following analytes would be *increased* due to delay in centrifugation? A. Bicarbonate B. Folate C. Ionized Calcium D. ALT
D. ALT The specimen should not be delayed for more than two hours prior to centrifugation because some of the analyte levels (such as glucose, ionized calcium, bicarbonate, folate, etc.) may be falsely decreased due to cellular consumption or falsely increased (such as potassium, ALT, AST, creatinine, etc.) because they are released over time from cells into serum or plasma.
Motility is a key initial assessment in the presumptive identification of the nonfermentative gram-negative bacilli. All of the following organisms are motile EXCEPT? A. Burkholderia cepacia B. Alcaligenes faecalis C. Pseudomonas aeruginosa D. Elizabethkingia meningoseptica
D. Elizabethkingia meningoseptica
All of the following are Lancefield carbohydrate antigens found on beta-hemolytic Streptococcus species. All of the following antigens are found on organisms from the Streptococcus anginosus group EXCEPT? 1. A 2. B 3. F 4. G
2. B The group B Lancefield carbohydrate antigen is found on Streptococcus agalactiae. Groups A, C, F, & G Lancefield carbohydrate antigens can be found on Streptococcus anginosus.
The laboratory workplace includes many hours of computer use. The suggested time for a break after 30 minutes of computer use is: A. 1-2 minute break B. 3-5 minute break C. 5-10 minute break D. 20 minute break
A. 1-2 minute break It is suggested that after 30 minutes of computer use, a 1 to 2-minute break will provide the eyes a break to avoid fatigue. After each hour, an employee should take a 5 to 10-minute break.
The ketone component that is measured by the nitroprusside reaction is: A. Acetoacetic acid B. Beta-hydroxybutyric acid C. Acetone D. C-Reactive Protein
A. Acetoacetic acid A positive ketone result is demonstrated as a color change from purple to violet. The intensity of the violet color is proportional to the concentration of ketone bodies in the urine.
What urine contaminant could cause a falsely elevated level of urinary albumin, thus giving the false interpretation of kidney damage? A. Blood from menstruation B. Feces from urine collections during bowel movement C. Incomplete cleaning of the genitalia with a disinfectant prep pad D. Diluting the urine sample with water
A. Blood from menstruation The level of protein and albumin in blood is far higher than that of urine. For this reason, women should be instructed not to collect urine samples for protein and albumin analysis during menstruation.
Which of the following analytes would be *increased* due to delay in centrifugation? A. Creatinine B. Ionized Calcium C. Folate D. Bicarbonate
A. Creatinine The specimen should not be delayed for more than two hours prior to centrifugation because some of the analyte levels (such as glucose, ionized calcium, bicarbonate, folate, etc.) may be falsely decreased due to cellular consumption or falsely increased (such as potassium, ALT, AST, creatinine, etc.) because they are released over time from cells into serum or plasma.
Which of the following is the most common condition associated with a nonmegaloblastic macrocytic anemia? A. Liver disease B. Aplastic anemia C. Chronic blood loss D. Folic Acid deficiency
A. Liver disease The most common condition associated with nonmegaloblastic macrocytic anemia is liver disease, including cirrhosis due to alcoholism. While aplastic anemia can appear macrocytic, it is often normocytic. Anemia due to chronic blood loss is typically macrocytic. Folic Acid deficiency can lead to macrocytic anemia but is megaloblastic, not nonmegaloblastic.
Which of the following may be seen in a CSF sample of a patient that has a subarachnoid (intracranial) hemorrhage (SAH)? A. Macrophages containing hemosiderin B. Uneven distribution of blood in CSF tubes collected C. Clot is present in the CSF sample D. Supernatant of CSF sample does not have xanthochromia
A. Macrophages containing hemosiderin Characteristics of a subarachnoid hemorrhage (SAH) include even distribution of blood in tubes collected, no clot formation in the sample, as well as a xanthochromic supernatant to the sample. Another characteristic that correlates with a SAH is hemosiderin deposits in macrophages. As red blood cells degenerate, the breakdown products are seen in macrophages as dark, granular, iron-laden hemosiderin deposits.
Which of the following Mycobacterium species is positive for nitrate reduction? A. Mycobacterium tuberculosis B. Mycobacterium bovis C. Mycobacterium simiae D. Mycobacterium ulcerans
A. Mycobacterium tuberculosis
What procedure utilizes leukapheresis to collect the buffy coat from whole blood? A. Photopheresis B. Plasmapheresis C. Therapeutic apheresis D. Erythrocytapheresis
A. Photopheresis
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 cannot prevent alloimmunization of the recipient to antigens on transfused cells since patients and donor units are not phenotyped for every antigen prior to transfusion.
All of the following conditions would be associated with an increased level of alpha-fetoprotein, EXCEPT? A. Prostate Cancer B. Hepatocellular Carcinoma C. Viral Hepatitis D. Testicular Tumors
A. Prostate Cancer AFP is not found in increased levels in patients with prostate cancer. PSA, or prostate-specific antigen, is commonly used to screen for prostate cancer, not AFP. Hepatocellular carcinoma, viral hepatitis, testicular tumors, and pancreatic cancer are all associated with increased levels of AFP. In addition, liver cirrhosis and gastric cancers can also have an associated increased AFP level.
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
A urine concentration test was performed on a patient after a fluid intake deprivation period with the following findings: After 12 hours Urine Osmolality = 850 mOsm/Kg After 16 hours Urine Osmolality = 850 mOsm/Kg What do these results indicate? A. This represents normal kidney function. B. This represents a loss of tubular function and concentrating ability. C. This represents a laboratory error, as these results are not medically possible. D. These results represent end-stage renal disease.
A. This represents normal kidney function. A urine osmolality of 800 mOsm or higher is considered normal when patients were deprived of fluid for 12 hrs. A concentration test is used to determine the ability of the tubules to reabsorb the essential salt and water that have been non-selectively filtered by the glomerulus. The loss of tubular reabsorption capability is often the first function affected in renal disease.
Which one of the following analytes usually shows a decrease during an acute phase response? A. Transferrin B. Ceruloplasmin C. Alpha-1 Antitrypsin D. Fibrinogen
A. Transferrin Transferrin is a "negative" acute phase protein since it is found in decreased levels during acute phase response. Other "negative" acute phase proteins include albumin and transthyretin. Alpha-1-antitrypsin, fibrinogen, and ceruloplasmin are all "positive" acute phase proteins that are found in increased levels during acute phase response. Other "positive" acute phase proteins include alpha-1- acid glycoprotein, haproglobin, C3, C4, C-reactive protein, and serum amyloid.
Which of the following best describes the methodology for FISH? A. Uses directly labeled fluorescent nucleotides or probes with reporter molecules that are indirectly detected by fluorescent antibodies or affinity molecules B. Signal amplification test that uses signal amplification and alkaline phosphatase C. Target amplification test that uses thermal cycling and DNA polymerase D. Target amplification test using thermal cycling and DNA ligase
A. Uses directly labeled fluorescent nucleotides or probes with reporter molecules that are indirectly detected by fluorescent antibodies or affinity molecules Branched DNA (bDNA) uses signal amplification by measuring nucleic acid directly by signal amplification with alkaline phosphatase labels. Polymerase chain reaction (PCR) is a test amplification procedure with thermal cycling and DNA polymerase as the enzyme for amplifying the desired sequence. Ligase chain reaction (LCR) is similar to PCR, however, it uses DNA ligase to enhance amplification of the sequence using thermal cycling instead of polymerase like PCR.
*Calcofluor white* is used for: A. Visualization of fungal structures with fluorescent microscopy B. Separation of bacteria into two categories based on cell wall composition C. Visualization of protozoa in direct wet mounts or smears D. Visualization of bacteria in specimens where debris may be present
A. Visualization of fungal structures with fluorescent microscopy
What should be added to the cytocentrifuge chamber when preparing slides on serous fluids to aid in the adhesion of cells to the slide and preserve cellular morphology? A. Hyaluronidase B. 22% Albumin C. 10% acetic acid D. Sterile saline
B. 22% Albumin The addition of albumin helps preserve cellular morphology and improves adhesion to the slide. 10% acetic acid can be used as a diluent for grossly bloody serous fluids and CSF. The acetic acid lyses the red blood cells to increase the visualization of the nucleated cells present. Sterile saline can be used for dilutions.
Serum proteins can be separated by cellulose acetate electrophoresis into how many basic fractions: A. 4 fractions B. 5 fractions C. 6 fractions D. 7 fractions
B. 5 fractions Cellulose acetate electrophoresis separate serum proteins into 5 fractions: albumin, a1-globulins, a2-globulins, ß-globulins, and gamma-globulins.
In order to prevent a loss of viability in platelet concentrates during storage, the pH must be maintained at or above what level? A. 7.5 B. 6.2 C. 5.0 D. 4.5
B. 6.2 The proper pH for a unit of platelets must be at or above 6.2.
When the body compensates for a respiratory or metabolic disorder, the MAIN goal is to achieve: A. Correct carbonic acid level since it is the most important system in the body. B. A normal pH C. Normal pO2 and pCO2 for normal respiration D. Correct bicarbonate level since it is the most important system in the body.
B. A normal pH
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 Acute intermittent porphyria is a neurological porphyria. Porphyria cutanea tarda, Congenital erythropoietic porphyria, and Erythropoietic protoporphyria are all cutaneous porphyrias.
Which enzyme is responsible for the rate-limiting step of steroid hormone synthesis? A. 21-hydroxylase B. CYP450 C. F-zone enzymes D. 17-hydroxylase
B. CYP450
The recovery of this bacterial species from diarrhea stool specimens requires the use of selective culture media such as Butzler selective media or Skirrow blood agar incubated at 42° C in an atmosphere of 5% oxygen, 10% CO2, and 85% nitrogen. Growth on Skirrow blood agar as illustrated in the upper image are confluent smooth non-hemolytic colonies growing along the streak line with lateral extensions (arrows). Slender, long branching, S-shaped Gram negative rods are observed on Gram stain, as observed in the lower image. Positive reactions for oxidase, indoxyl, and hippurate provide for a more definitive identification. With these observations, select the name of this isolate. A. Campylobacter coli B. Campylobacter jejuni C. Helicobacter cinaedi D. Cardiobacterium hominis
B. Campylobacter jejuni Distinctive for C. coli is the negative reactions for indoxyl and hippurate.
This species of Candida accounts for around 20 percent of urinary yeast isolates. A. Candida albicans B. Candida glabrata C. Candida krusei D. Candida tropicalis
B. Candida glabrata Candida glabrata is the second most common Candida species to cause disease (Candida albicans is the most common). In urinary yeast isolates, it is identified about 20 percent of the time. Infections tend to be aggressive and difficult to treat with traditional antifungal therapy. It has different sugar assimilation patterns than Candida albicans, notably rapid assimilation of trehalose, so it can easily be differentiated. Candida krusei and Candida tropicalis are seen in immunocompromised patients and cause nosocomial infections.
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 has its natural habitat in the oropharynx of humans and would not be involved in dog bite infections. All of the other bacterial species listed in this question reside in the oropharynx of dogs and other canines and may cause human dog bite infections.
The laboratory receives a synovial fluid for acid-fast culture. How should the tech proceed with this culture? A. Digest the sample for culture B. Centrifuge the specimen and directly inoculate the culture C. Perform a direct smear only D. Reject the specimen
B. Centrifuge the specimen and directly inoculate the culture Body fluids, such as synovial fluid and spinal fluid, do not have normal flora like respiratory specimens. Thus, these samples do not need to be digested before setting up the culture. The specimen should be centrifuged, unless the volume is very low, then the sediment is used to inoculate the smears and culture media.
The image shows an antimicrobial susceptibility result for a Corynebacterium species on a 5% sheep blood agar plate. The zone around the 10 µg penicillin disk rules out: A. Corynebacterium minitissmum B. Corynebacterium ureolyticum C. Corynebacterium xerosis D. Corynebacterium aquaticum
B. Corynebacterium ureolyticum Corynebacterium ureolyticum is one of a few species of Corynebacterium, including C. amycolatum, C. jeikeium, and C. resistens, that are resistant to penicillin and most other antibiotics. The 10 µg penicillin disk is often used in the initial identification of Corynebacterium species to screen for C. jeikeium. For this question, C. ureolyticum is the only available answer that is resistant to penicillin.
A Rh negative individual has produced an anti-D antibody. Which situation has the ability to stimulate this production of anti-D? A. Delivering a Rh negative baby. B. Delivering a Rh positive baby. C. Receiving Rh negative packed red blood cells. D. Receiving Rh positive fresh frozen plasma.
B. Delivering a Rh positive baby.
All of the following are roles of a sentinel microbiology laboratory, EXCEPT? A. Rule out pathogens. B. Determine that a bioterrorist event has occurred. C. Transfer suspicious specimens to reference laboratories. D. Be familiar with likely agents involved in a bio crime.
B. Determine that a bioterrorist event has occurred. The role of a sentinel laboratory is to receive patient samples, rule out pathogens, and transfer suspicious specimens to reference laboratories. A reference laboratory confirms the presence of biological terror agents.
Which of the statements below regarding the diagnosis of pancreatitis is CORRECT? A. Amylase and lipase are as predictive in chronic as in acute pancreatitis. B. Diagnostic sensitivity for acute pancreatitis is increased by assaying both amylase and lipase. C. Chronic pancreatitis occurs more often in women. D. Increased amylase levels stay increased after the cause of the pancreatitis is removed.
B. Diagnostic sensitivity for acute pancreatitis is increased by assaying both amylase and lipase. Increased levels of amylase and lipase are very useful for detecting acute pancreatitis. In chronic pancreatitis, amylase and lipase levels may not be elevated and, in fact, can decrease over time, so these tests are not as predictive for chronic pancreatitis as they are for acute.
Which of the following is a confirmatory test for syphilis? A. RPR B. FTA-ABS C. VDRL D. Automated Reagin Test (ART)
B. FTA-ABS FTA-ABS (Fluorescent Treponema pallidum absorption test) should only be used to differentiate between true positives, false positives, and in late or latent syphilis. RPR, VDRL, and ART are screening tests for syphilis.
All of the following represent a 2 week temporary deferral from donating blood or blood products EXCEPT: A. Measles (rubeola) vaccine B. German measles (rubella) vaccine C. Mumps vaccine D. Polio vaccine
B. German measles (rubella) vaccine A potential blood donor who has received a German measles (rubella) vaccine is deferred for 4 weeks following the vaccination. Measles (rubeola), mumps, and polio vaccines all have a 2 week deferral period following the vaccination.
Which of the following statements best describes Rh antibodies? A. Naturally occurring, IgM B. Immune, IgG C. Naturally occurring, IgG D. Immune, IgM
B. Immune, IgG Rh antibodies are typically IgG class immunoglobulins, and occur as a result of exposure to the corresponding antigens, through pregnancy or transfusion, and thus are considered "Immune". Rh antibodies are not typically naturally occurring or of the IgM class of immunoglobulins.
High levels of lipoprotein-associated phospholipase A2 (Lp-PLA2) are associated with: A. Decreased cardiovascular risk B. Increased cardiovascular risk C. Increased renal failure risk D. Increased liver failure risk
B. Increased cardiovascular risk A concentration of >200µg/L is considered to be a risk for a cardiovascular event.
Using molecular methods to identify organisms can provide GREATER specificity when compared to phenotypic methods. Which of the following organisms would molecular methods not be beneficial over phenotypic methods in identification? A. Corynebacterium and related genera B. Klebsiella species C. Nocardia and related genera D. Dimorphic mycologic pathogens
B. Klebsiella species Enterobacteriaciae such as Klebsiella can still be reliably and easily identified by phenotypic (biochemical) methodologies.
All of the following are causes of hypernatremia EXCEPT: A. Excess water loss B. Low aldosterone production C. Decreased water intake D. Increased sodium intake or retention
B. Low aldosterone production Excess water loss, decreased water intake, and increased sodium intake and retention are all causes of high levels of sodium (hypernatremia). Hypernatremia is seen in diabetes insipidus due to excess water loss and in hyperaldosteronism (increased retention of sodium). Aldosterone is a hormone produced by the adrenal cortex. Aldosterone stimulates sodium reabsorption in the distal tubules of the nephron. Low levels of aldosterone would not promote increased levels of sodium.
You are collecting a blood specimen to be used for forensic (legal) alcohol testing. Which of the following must be done before you can start the specimen collection process? A. Label the tubes in the presence of the patient. B. Must inform the patient that the blood about to be collected is for alcohol testing. C. Seal the collection tubes in front of the patient. D. Collect the specimen, the patient does not need to be informed what the blood is collected for.
B. Must inform the patient that the blood about to be collected is for alcohol testing. Labeling the blood tubes and sealing them in front of the patient is done after collection is complete.
The human infections related to the 60 X 40 µm ovum, as illustrated in the image, are reported by the World Health Organization to involve several million people worldwide. Symptoms vary from nausea and diarrhea in patients with light infection, to peripheral edema, anemia, dehydration, and congestive heart failure in those with heavy infections. Select the most likely genus/species identification. A. Enterobius vermicularis B. Necator americanus C. Trichuris trichiura D. Ascaris lumbricoides Picture shows: thin, smooth, transparent shell with the developing internal yolk sack retracting from the shell leaving an open clear space.
B. Necator americanus
Which analyte shows no difference between capillary and venous values? A. Glucose B. Phosphorus C. Bilirubin D. Calcium
B. Phosphorous Phosphorus and urea show no difference between capillary and venous values. Glucose and Potassium capillary values are greater than venous values. Bilirubin and Calcium capillary values are less than the venous values. Capillary values of chloride, sodium and total protein will also show less than venous values.
Which one of these test systems can be used to evaluate the adequacy of fibrinogen in heparinized patients? A. D-Dimer B. Reptilase Time C. Thrombin Time D. Prothrombin Time
B. Reptilase Time Reptilase time can be performed on blood that contains heparin since it does not interfere with the clotting process in this test. Patients who have qualitative or quantitative fibrinogen disorders are associated with prolonged reptilase time results.
In the evaluation of a positive DAT result, all of the below techniques can be used to dissociate the antibody(ies) form the RBCs EXCEPT: A. EDTA-glycine B. Saline replacement C. Chloroquine diphosphate D. Murine monoclonal antibodies
B. Saline replacement
*Gram stain* is used for: A. Visualization of fungal structures with fluorescent microscopy B. Separation of bacteria into two categories based on cell wall composition C. Visualization of protozoa in direct wet mounts or smears D. Visualization of bacteria in specimens where debris may be present
B. Separation of bacteria into two categories based on cell wall composition
The first intermediate host in the fluke life cycle is the: A. Copepod B. Snail C. Fish D. Water plant
B. Snail
A WBC differential count on CSF should be performed using the following technique: A. Wet mount of sample from collection tube B. Stained smear of a cytocentrifuged specimen C. Directly from hemocytometer chamber count D. Directly from stained hemocytometer count
B. Stained smear of a cytocentrifuged specimen Differential counts on CSF should be performed on stained smears made from a cytocentrifuged specimen. The cytocentrifugation process distributes the cellular elements in a monolayer, making it easy to distinguish the cells' morphology when observed under the microscope. Cell type cannot be reliably assessed on unstained specimens or from the hemocytometer.
All of the following carbohydrates are considered reducing sugars EXCEPT: A. Lactose B. Sucrose C. Glucose D. Ribose
B. Sucrose
A mother's serologic results show as type O positive with negative screens. Her newborn types as group A Rh positive with a (1+) positive direct antiglobulin test (DAT). Which of the following investigative tests would be most useful to resolve the cause of the positive DAT and should be done *FIRST*? A. Test an eluate prepared from newborn's red cells against an antibody identification panel by IAT. B. Test newborn's plasma against group A1 red cells and group O antibody screen cells by IAT. C. Test newborn's plasma against mother's red cells by IAT. D. Test newborn's plasma against father's red cells by IAT.
B. Test newborn's plasma against group A1 red cells and group O antibody screen cells by IAT. Results are consistent with a possible case of ABO HDFN. ABO HDFN is nearly always limited to A or B infants of group O mothers with potent anti-A,B. The most useful follow-up would be to test the infant's plasma against A1 red cells and group O antibody screen cells (as a control), expecting only the A1 cells to be positive (due to the mother's anti-A,B because she is group O) if the DAT was due to ABO incompatibility.
The gram negative bacillus illustrated in the lower photomicrograph was recovered from a skin wound incurred while the patient was swimming in sea water around the Western U.S. coast of the Gulf of Mexico. Note that the gray-yellow colonies grow well on blood agar (upper composite image to the left), but the *colonies on TCBS agar (Thiosulfate Citrate Bile Sucrose - composite image to the right) are pale green, indicating the lack of sucrose utilization*. The short, slightly curved gram negative bacilli seen in a gram stain (lower photomicrograph) are consistent with Vibrio species, but not species specific. Select the presumptive identification of this isolate. A. Vibrio cholerae B. Vibrio vulnificus C. Aeromonas hydrophila D. Plesiomonas shigelloides
B. Vibrio vulnificus The light green rather than yellow pigmented colonies on TCBS agar indicates lack of sucrose fermentation serving to separate V. vulnificus from V. cholera. Lactose fermentation is positive.
Which of the following blood tests is used to determine acute pancreatitis? A. Acid phosphatase B. Uric acid C. Amylase D. Alkaline phosphatase (ALP)
C. Amylase Acid phosphatase test helps in diagnosing prostate cancer. Uric acid is a test used to diagnose gout in a patient. ALP is the test used to evaluate liver function.
If detected in antibody screen testing, which of the following antibodies is NOT considered clinically significant in prenatal patients? A. Anti-M B. Anti-N C. Anti-Leb D. Anti-Fya
C. Anti-Leb Anti-Leb may be detected in antibody screen testing of prenatal patients; however, this antibody is considered clinically insignificant. It is not indicated in causing hemolytic disease of the fetus and newborn (HDFN). Although rarely seen, both anti-M and anti-N can potentially cause mild to moderate HDFN. The most common clinically significant antibodies noted in prenatal patients include the following: anti-Fya, anti-K, anti-D, anti-E, anti-e, anti-C, and anti-c. These IgG antibodies have been determined to cause moderate to severe HDFN.
What do the two and/or three reagent cells used for antibody screening detect? A. Antibodies to most white cell antigens B. Antibodies to red cell A and B antigens C. Antibodies to common alloantigens D. Antibodies to most private (low incidence) red cell antigens
C. Antibodies to common alloantigens Screening cells licensed by the FDA require an antigen profile capable of detecting most clinically significant red cell antibodies (common alloantibodies). Screening cells are for the detection of preformed red cell antibodies. Screening cells are group O, and will, of course not detect antibodies to A and B antigens.
Which of the following consequences of severe hemolytic disease of the fetus and newborn (HDFN) is most associated with neonatal death before or shortly after birth? A. Enlarged liver B. Enlarged spleen C. Cardiac failure D. Hyperbilirubinemia
C. Cardiac failure As red cell destruction continues, the fetus becomes increasingly anemic. The fetal liver and spleen enlarge as erythropoiesis increases to compensate for the red cell destruction. Hemoglobin is liberated from the damaged cells, metabolized to indirect bilirubin and is transported across the placenta where it is conjugated by the maternal liver and excreted. As the red cell destruction continues, cardiac failure resulting from uncompensated anemia will occur.
Illustrated in the photomicrograph is a small pear-shaped ovum, averaging 25 - 35 µm that was found in a stool specimen. The shell is smooth and slightly thickened. Distinctive is the shouldered operculum at the cephalic end of the shell and a small knob at the posterior margin (arrows). Developing larvae at varying stages are observed internally. The adults are most commonly found within the liver bile duct system which may lead to obstruction and intermittent jaundice. What is the best presumptive identification? A. Paragonimus westermani B. Trichuris trichiura C. Clonorchis sinensis D. Fasciola hepatica
C. Clonorchis sinensis
Platelets are: A. The smallest nucleated cells seen in normal peripheral blood. B. The largest nucleated cells seen in normal peripheral blood. C. Fragments of megakaryocyte cytoplasm and do not contain nuclei D. Fragments of neutrophils
C. Fragments of megakaryocyte cytoplasm and do not contain nuclei Platelets do not contain nuclei. They are fragments of megakaryocyte cytoplasm. Therefore, they are not the smallest nor the largest nucleated cells found in peripheral blood. Neutrophils do not produce platelets.
Which of the following species of bacteria is positive for rapid urease production, as demonstrated by a color change in urea agar from yellow to pink within two hours? A. Salmonella enterica B. Escherichia coli C. Helicobacter pylori D. Campylobacter jejuni
C. Helicobacter pylori Salmonella enterica, Escherichia coli, and Campylobacter jejuni are also Gram-negative rods implicated in enteric infections but are urease negative.
How does hydroxyurea aid in the treatment of sickle cell disease? A. Acts as an analgesic in pain management. B. Prevents sickle cells from clumping together. C. Induces increased production of HbF. D. Reduces the number of sickle cells that form.
C. Induces increased production of HbF. Anti-inflammatory agents are given to serve as an analgesic in pain management for sickle cell patients. Nitric oxide treatment prevents sickle cells from clumping together. Clotrimazole is an over-the-counter antifungal medication. This drug prevents water loss from the red blood cells, which helps prevent the formation of sickle cells.
Which of the following tests on amniotic fluid would be included when assessing fetal lung maturity: A. Alpha Fetoprotein B. Bilirubin C. L/S Ratio D. Fetal hemoglobin
C. L/S Ratio Because amniotic fluid is continuously swallowed or inhaled and then replaced or exhaled in uterus the ratio can be measured to determine how much surfactant is in the fetal lungs. This ratio will help determine how well the infant's lungs will perform breathing at birth. Alpha-fetoprotein is used in assessing the potential for genetic disorders. Bilirubin is used in diagnosing the cause of jaundice and other liver problems. Fetal hemoglobin is not used to assess fetal lung maturity.
A variety of additives are used in blood collection tubes. Which of the following additives prevents clotting by inhibiting thrombin and thromboplastin? A. EDTA B. Gel C. Lithium or sodium heparin D. Sodium fluoride
C. Lithium or sodium heparin Lithium/sodium heparin is an additive used to prevent clotting by inhibiting thrombin and thromboplastin. It is found in green and light green tubes. EDTA prevents blood from clotting by binding calcium, which in turn inhibits the coagulation cascade. EDTA is found in lavender, pink, white, royal blue, and tan top tubes. The gel in the tube is used to form a barrier between plasma/serum and blood cells upon centrifugation. Sodium fluoride is found in gray top tubes and its purpose is to inhibit glycolysis (metabolism of glucose by red blood cells).
Which of the following major cellular elements does not develop solely in the bone marrow? A. Monocyte B. Neutrophil C. Lymphocyte D. Macrophage
C. Lymphocyte Lymphocytes may be produced not only in the bone marrow but also in lymphoid tissues.
The following are described as rapid growing, opportunistic fungi that are differentiated based on the presence of sporangiospores, the shape of the columella, presence or absence of rhizoids, and the location of the rhizoids on the stolon. A. Aspergillus species B. Penicillium species C. Mucorales species D. Dermatophyte species
C. Mucorales species Mucorales species include the rapidly growing Absida, Mucor, and Rhizopus species.
Which of the following is an expected or common laboratory finding in patients with hereditary hemochromatosis (HH)? A. Elevated hemoglobin and hematocrit B. Decreased transferrin saturation C. Presence of HFE mutation D. Decreased serum ferritin
C. Presence of HFE mutation (HH) is an inherited condition where there is increased iron absorption in the gut with iron overload over time. Typical laboratory findings in HH include the presence of an HFE mutation. Patients with HH will generally present with elevated transferrin saturation and elevated serum ferritin.
Which one of the following statements about lead poisoning is *false*? A. While lead distributes to all tissues, the central nervous system, kidney, and bone marrow are particularly susceptible to lead toxicity B. Whole blood lead measurement is the best test for detecting lead toxicity C. Serum lead level is a good inexpensive screening test for lead toxicity D. Lead levels below 5 µg/dL in children do not prompt ongoing monitoring
C. Serum lead level is a good inexpensive screening test for lead toxicity While lead distributes to all tissues, the central nervous system, kidney, and bone marrow are particularly susceptible to lead toxicity. Serum lead levels are of little value, since they fluctuate rapidly, and do not remain positive very long after episodes of exposure to lead. Whole blood lead measurement is the best test for detecting lead toxicity. The CDC recommends to monitor lead levels and if the upper limit is above 5 µg/dL in children to prompt ongoing monitoring. The goal is to keep levels below 10 µg/dL in children.
Adult Ascaris lumbricoides worms reside in the: A. Lungs B. Liver C. Small intestines D. Large intestines
C. Small intestines Although the larval form of Ascaris migrates through the lung, where it can cause Loeffler's syndrome, the mature form lives in the duodenum or proximal jejunum within the small intestines.
A chemical reaction that is utilized by many different analytical methods involves: A. Fluorometry B. Glucose oxidase C. The reduction of NAD to NADH D. UV spectrophotometry
C. The reduction of NAD to NADH In addition, several different analytical methods can use this method because it is not a light-producing dependent reaction. Fluorometry is an analytical method that is dependent on analytes that have the ability to fluoresce. Glucose oxidase is an enzymatic glucose oxidase method used to measure the amount of glucose present in a sample. UV spectrophotometry is an analytical method dependent on the light-producing ability of analytes present in the sample.
A prothrombin time (PT) specimen was collected at an outpatient clinic and will not be picked up by the testing laboratory's courier until several hours later. How should the specimen be stored until it is picked up by the courier? A. The specimen should be centrifuged right away and stored in the refrigerator at 4° C until is picked up the the courier. B. The specimen should be frozen immediately and kept there until is tested. C. The tube should remain unopened and be kept at room temperature (20°-25° C). D. The specimen should be protected from light.
C. The tube should remain unopened and be kept at room temperature (20°-25° C). Temperatures between 2° - 4° C may result in cold activation of factor VII that would alter the PT result. The tube should not be opened to remove the plasma before testing if the test will be completed within 24 hours of collection. Plasma should be removed and frozen at -20° C or lower if the PT test is not completed within 24 hours. Whole blood should never be frozen because the red cells will lyse, and the PT test result would be drastically altered. The specimen does not require protection from light.
Which troponin protein binds the troponin complex to tropomyosin? A. Troponin I (TnI) B. Troponin C (TnC) C. Troponin T (TnT) D. Troponin P (TnP)
C. Troponin T (TnT) TnT binds the troponin complex to tropomyosin. *TnI inhibits* the binding of actin and myosin. *TnC binds to calcium* to reverse the inhibitory activity of TnI. Troponin is a complex of three proteins (TnT, TnI, and TnC) that regulates the calcium-dependent interactions of myosin heads with actin filaments during striated muscle contraction, so *there isn't a Troponin P*.
*Trichrome stain* is used for: A. Visualization of fungal structures with fluorescent microscopy B. Separation of bacteria into two categories based on cell wall composition C. Visualization of protozoa in direct wet mounts or smears D. Visualization of bacteria in specimens where debris may be present
C. Visualization of protozoa in direct wet mounts or smears
In the following list of organisms, which organism is considered cryophilic (can grow as low as 4° C)? A. Escherichia coli B. Pseudomonas aeruginosa C. Yersinia enterocolitica D. Campylobacter jejuni
C. Yersinia enterocolitica This is an important implication in that this organism is a possible infective agent in cases of transfusion-related septicemia as the organisms can survive and replicate at the storage temperature of blood products.
Which marker is most useful for the detection of gestational trophoblastic disease? A. CEA (Carcinoembryonic antigen) B. AFP (a-fetoprotein) C. hCG (human chorionic gonadotropin) D. CA-125 (cancer antigen 125)
C. hCG (human chorionic gonadotropin) hCG is used for pregnancy testing, but it is also the most useful marker for the detection of gestational trophoblastic disease. The main clinical use of CEA is a marker for colorectal cancer. AFP is often elevated in patients with hepatocellular carcinoma and germ cell tumors. CA-125 is a serological marker of ovarian cancer.
A 21-year-old male presented to the emergency room complaining of abdominal pain, fever, cough, nausea, vomiting, and constipation alternating with diarrhea. Radiologic studies revealed the presence of a hepatic abscess. The form in this image (Entamoeba histolytica trophozoite), measuring 20 µm, was seen in the microscopic examination of a sample taken from the abscess. What condition is the patient most likely suffering from? A. Intestinal amebiasis B. Meningoencephalitis C. Giardiasis D. Extraintestinal amebiasis
D. Extraintestinal amebiasis The form found in the abscess sample and the patient's symptoms indicate this is extraintestinal amebiasis caused by Entamoeba histolytica. Intestinal amebiasis is limited to the intestine. This infection also involved the liver. Meningoencephalitis is defined as the presence of inflammation in the meninges and the brain. This is not consistent with the case described. The organism image is not consistent with Giardiasis which is caused by Giardia duodenalis. Also, Giardia does not invade the mucosal surface to cause extraintestinal infections.
Which FAB designation is called the "true" monocytic leukemia and is characterized by monoblasts, promonocytes, and monocytes? A. FAB M1 B. FAB M3 C. FAB M4 D. FAB M5
D. FAB M5 FAB M5 is acute monoblastic leukemia. Most cells are monocytes. There are 2 subtypes. Subtype a is characterized by large blasts in the bone marrow and peripheral blood. Subtype b is characterized by monoblasts, promonocytes, and monocytes. FAB M1 is acute myeloblastic leukemia without maturation. Blasts and promyelocytes predominate with minimal maturation of myeloid cells. FAB M3 is acute promyelocytic leukemia. Promyelocytes predominate in the bone marrow. FAB M4 is acute myelomonocytic leukemia. Myeloid and monocytic cells represent at least 20% of the total leukocytes.
Which one of these Lewis blood group system phenotypes usually produces anti-Lea? A. Le(a+b+) B. Le(a+b-) C. Le(a-b+) D. Le(a-b-)
D. Le(a-b-) This antibody can occur almost exclusively in the serum of Le(a-b-) individuals and can occur without red blood cell stimulus. It is typically found as a clinically insignificant, naturally occurring IgM antibody. Phenotypes other than Le(a-b-) rarely produce the corresponding antibody.
Which of the following is most likely to interfere with the measurement of hemoglobin? A. Leukocytopenia B. EDTA C. Heparin D. Lipemia
D. Lipemia Increased turbidity of the specimen may interfere with the measurement of hemoglobin and result in a falsely increased hemoglobin result. Lipemia, leukocytosis, paraproteinemia, cryoglobulinemia, cryofibrinogenemia, and presence of abnormal hemoglobin (e.g., HbS, HbC), are all possible causes of increased turbidity.
A 67-year-old homeless man was seen in the ambulatory clinic for chest pain and sputum production. A mycobacterial culture showed the following: rough, non-pigmented colonies, which grew after two weeks at 35oC and failed to grow at other temperatures, serpentine cording, a strongly positive niacin test, nitrate reduction, and loss of catalase activity after heating at 68oC in pH 7. What is the most likely identification? A. Mycobacterium bovis B. Mycobacterium intracellulare C. Mycobacterium kansasii D. Mycobacterium tuberculosis
D. Mycobacterium tuberculosis
A patient has a history of repeated spontaneous abortion. Coagulation studies reveal an elevated APTT, normal PT, normal platelet function, and normal thrombin time. Schistocytes were seen on the peripheral blood smear. Which test should be performed to determine if the patient has lupus anticoagulant? A. Factor VIII assay B. Mixing studies with factor-deficient plasmas C. Antinuclear antibody test D. Platelet neutralization test
D. Platelet neutralization test Platelet neutralization tests are one of the confirmatory tests that can be used to determine if a patient has a circulating lupus antibody, or lupus anticoagulant. The principle in this test involves the use of a freeze-thawed platelet suspension that, when mixed with the patient plasma, will neutralize the anti-phospholipid antibodies (lupus anticoagulant) present and allow for a corrected APTT result upon re-testing. The antinuclear antibody test is a screening test for autoimmune diseases such as systemic lupus erythematosus (SLE). Although some patients with SLE may have a lupus anticoagulant, not all patients with lupus anticoagulant have SLE.
When a patient has a bile duct obstruction, the bilirubin test portion of the reagent strip is: A. Negative because unconjugated bilirubin is increased and cannot be excreted by the kidneys. B. Positive because unconjugated bilirubin is increased and is excreted by the kidneys. C. Negative because conjugated bilirubin is decreased and cannot be excreted by the kidneys. D. Positive because conjugated bilirubin is present and is excreted by the kidneys.
D. Positive because conjugated bilirubin is present and is excreted by the kidneys. Unconjugated bilirubin, usually caused by red blood cell breakdown, is not able to be excreted from the kidneys, and will not cause a positive urine bilirubin result.
Which adsorption technique removes cold (IgM) antibodies, particularly anti-I specificities? A. Cold autoadsorption B. Warm autoadsorption C. Differential (allogeneic) D. Rabbit erythrocyte stroma (RESt)
D. Rabbit erythrocyte stroma (RESt) RESt removes cold (IgM) antibodies, particularly anti-I specificities. However, it may adsorb anti-B and other IgM antibodies. Cold autoadsorption uses patient red cells to remove cold autoantibodies to determine whether alloantibodies are present. Warm autoadsorption uses patient red cells are used to remove warm autoantibodies to determine whether alloantibodies are present. Allogeneic adsorption uses known phenotyped red cells to separate specificities: 1) warm autoantibodies from alloantibodies 2) alloantibodies with several specificities.
Which of the following organisms is the leading cause of bacterial meningitis in infants, young children, and adults in the United States? A. Haemophilus influenzae B. Neisseria meningitidis C. Pediococcus spp. D. Streptococcus pneumoniae
D. Streptococcus pneumoniae Streptococcus pneumoniae is the leading cause of bacterial meningitis in the groups listed. Followed by Neisseria meningitidis and Haemophilus influenzae. Pediococcus spp. usually are only capable of causing infections in severely immunocompromised individuals.
When a Specked Nuclear Antibody (ANA) pattern is observed, what follow-up test for antibodies related to Systemic Lupus Erythematosus (SLE) is not beneficial? A. Testing for antibodies to Smith (Sm) B. Testing for all antibodies to the extractable nuclear antigens (ENA) C. Testing for antibodies to SS-A/SS-B+ D. Testing for antibodies to U1RNP+ and dcSSc
D. Testing for antibodies to U1RNP+ and dcSSc U1RNP+ and Scl-70 antibodies are extractable nuclear antigens that yield a speckled ANA pattern, but they are not associated with Systemic Lupus Erythematosus (SLE). U1RNP+ is associated with mixed connective tissue disease/undifferentiated connective tissue disease; Scl-70+ is associated with Diffuse cutaneous scleroderma.
Circulating organic iodine is found primarily in the form of: A. Triiodothyronine B. Parathyroid hormone C. Thyroglobulin D. Thyroxine
D. Thyroxine Iodine is the basic element involved in the synthesis of thyroid hormones. Iodine circulates mostly as thyroxine (T4) and to a lesser extent as triiodothyronine (T3). About 80% of T3 comes from the monodeiodination of T4.
Which two of the following crystalline elements are found in acid urine: A. Cystine and calcium carbonate B. Triple phosphate and calcium carbonate C. Calcium phosphate and uric acid D. Tyrosine and cystine
D. Tyrosine and cystine Crystals and sediment found in acid urine include cystine, leucine, calcium oxalate, sodium urate, sulfonamide, tyrosine, uric acid, and amorphous urates.
*Acridine orange* is used for: A. Visualization of fungal structures with fluorescent microscopy B. Separation of bacteria into two categories based on cell wall composition C. Visualization of protozoa in direct wet mounts or smears D. Visualization of bacteria in specimens where debris may be present
D. Visualization of bacteria in specimens where debris may be present *Acridine orange* is a fluorochrome dye that binds to nucleic acids in bacterial specimens to aid in visualization.
Autologous blood donation hemoglobin and hematocrit requirement:
HGB: 11.0 g/dL HCT: 33%
Osmolality calculation:
Osmolality = 2Na + [Glucose / 20] + [BUN / 3]
Manual WBC count performed on hemocytometer calculation:
[ # cells counted x dilution factor ] / [ .1 x # squares counted ] Formula can not be calculated when cell counts on each side of the hemocytometer are greater than 10% of one another because they are considered discrepant.
