🩺 Q225: A patient sample is collected in a tube with the wrong additive, leading to hemolysis. How does this affect the potassium result?
Anonymous Quiz
0%
A) Falsely decreases potassium due to dilution.
69%
B) Falsely increases potassium due to intracellular release.
0%
C) No effect on potassium levels.
31%
D) Potassium levels are only affected if the sample is stored at room temperature.
🩺 Q226: What is the primary purpose of a 'Levey-Jennings' chart in laboratory quality control?
Anonymous Quiz
0%
A) To compare patient results to population normals.
87%
B) To monitor the performance of an analytical method over time.
13%
C) To calibrate the instrument at the start of each shift.
0%
D) To calculate the total allowable error (TEa).
🩺 Q227: Which of the following is considered the most effective method for decontaminating laboratory surfaces contaminated with bloodborne pathogens?
Anonymous Quiz
6%
A) 70% Isopropyl alcohol
94%
B) 10% Sodium hypochlorite (bleach)
0%
C) Soap and water
0%
D) UV light exposure
🩺 Q228: What does the 'analytical sensitivity' of a clinical assay refer to?
Anonymous Quiz
11%
A) The ability of the test to identify patients with the disease.
89%
B) The lowest concentration of an analyte that can be reliably detected.
0%
C) The ability of the test to exclude patients without the disease.
0%
D) The degree of agreement between replicate measurements.
🩺 Q229: What is a primary requirement for the handling of Proficiency Testing (PT) samples in a clinical laboratory?
Anonymous Quiz
41%
A) PT samples must be analyzed by the same staff and methods as routine patient samples.
47%
B) PT samples should be tested by the supervisor to ensure accuracy.
12%
C) PT samples can be shared with other laboratories to compare results.
0%
D) PT samples should be treated with special reagents not used for patient samples.
🩺 Q230: If a control result falls outside 3 standard deviations (1-3s rule), what does this indicate?
Anonymous Quiz
0%
A) The system is in control.
76%
B) A random error has likely occurred.
24%
C) A systematic error is present.
0%
D) The reagent has expired.
🩺 Q231: What is the purpose of a Safety Data Sheet (SDS) in the laboratory?
Anonymous Quiz
6%
A) To provide information on the clinical utility of a test.
82%
B) To outline the hazard profile, handling precautions, and emergency procedures for a chemical.
12%
C) To list the maintenance schedule for laboratory instrumentation.
0%
D) To record the results of annual competency assessments.
🩺 Q232: Which of the following is an example of a 'pre-analytical' error?
Anonymous Quiz
11%
A) Incorrect instrument calibration.
28%
B) Reporting a result for the wrong patient.
56%
C) Using an incorrect tube type for the requested test.
6%
D) A clerical error in the laboratory information system.
🩺 Q233: When using the cyanmethemoglobin method for hemoglobin determination, what reagent is used to convert hemoglobin to hemiglobincyanide?
Anonymous Quiz
0%
A) Sodium chloride and hydrochloric acid
81%
B) Potassium ferricyanide and potassium cyanide
13%
C) Drabkin's reagent with sodium azide
6%
D) Surfactants and hydrogen peroxide
🩺 Q234: Which of the following findings is considered a definitive WHO criterion for the diagnosis of Polycythemia Vera?
Anonymous Quiz
0%
A) Elevated serum erythropoietin levels
76%
B) Presence of JAK2 V617F mutation
12%
C) Increased marrow iron stores
12%
D) Presence of Philadelphia chromosome
🩺 Q235: A patient with severe vitamin K deficiency would likely show which coagulation profile results?
Anonymous Quiz
35%
A) Prolonged PT and normal APTT
41%
B) Normal PT and prolonged APTT
24%
C) Prolonged PT and prolonged APTT
0%
D) Normal PT and normal APTT
🩺 Q236: Which of the following is the most sensitive indicator of iron deficiency anemia in a patient with chronic inflammation?
Anonymous Quiz
0%
A) Serum iron
88%
B) Total iron-binding capacity (TIBC)
13%
C) Serum ferritin
0%
D) Transferrin saturation
🩺 Q237: A patient presents with hypertension, hypokalemia, and metabolic alkalosis. Plasma aldosterone is elevated, but plasma renin activity is suppressed. What is the most likely diagnosis?
Anonymous Quiz
0%
A) Secondary hyperaldosteronism
88%
B) Primary hyperaldosteronism (Conn syndrome)
13%
C) Renal artery stenosis
0%
D) Addison disease
🩺 Q238: Which enzyme is most specific for the diagnosis of liver disease when compared to bone or placental sources of elevated alkaline phosphatase?
Anonymous Quiz
13%
Aspartate aminotransferase (AST)
81%
B) Gamma-glutamyl transferase (GGT)
6%
C) Alanine aminotransferase (ALT)
0%
D) 5'-Nucleotidase
🩺 Q239: A 24-year-old male presents with a painful penile ulcer and inguinal lymphadenopathy. A darkfield microscopy of the exudate is negative. Which diagnostic test is the next most appropriate step to confirm primary syphilis?
Anonymous Quiz
13%
A) RPR (Rapid Plasma Reagin) test
80%
B) Treponema pallidum particle agglutination (TPPA) assay
0%
Culture on Thayer-Martin agar
7%
D) Gram stain of the lesion exudate
🩺 Q240: Which of the following describes the mechanism of TRALI (Transfusion-Related Acute Lung Injury)?
Anonymous Quiz
31%
A) IgE-mediated hypersensitivity to plasma proteins
63%
B) Donor antibodies against recipient leukocyte antigens
6%
C) Fluid overload due to rapid transfusion
0%
D) Bacterial contamination of the donor unit
🩺 Q241: Which antibody is most commonly associated with Delayed Hemolytic Transfusion Reactions (DHTR)?
Anonymous Quiz
0%
Anti-A
76%
B) Anti-Kidd (Jka)
18%
C) Anti-D
6%
D) Anti-Lewis
🩺 Q242: What is the shelf life of Platelet Concentrates stored at 20-24°C with continuous agitation?
Anonymous Quiz
18%
A) 24 hours
47%
B) 5 days
29%
C) 35 days
6%
D) 42 days
🩺 Q243: A patient returns from a trip to Southeast Asia and presents with persistent diarrhea. A stool O&P exam reveals large, oval eggs with a prominent operculum and a small abopercular thickening. What is the most likely parasite?
Anonymous Quiz
0%
A) Fasciolopsis buski
88%
B) Diphyllobothrium latum
6%
Clonorchis sinensis
6%
D) Paragonimus westermani
🩺 Q244: A laboratory isolate from a blood culture is a Gram-positive coccus in chains. It is catalase-negative and shows beta-hemolysis on sheep blood agar. The organism is resistant to bacitracin and shows positive growth in 6.5% NaCl broth. What is the identity of this organism?
Anonymous Quiz
13%
A) Streptococcus pyogenes
50%
B) Streptococcus agalactiae
0%
C) Enterococcus faecalis
38%
D) Streptococcus pneumoniae