Practice 5 MCQs on Chemical Pathology with OmpathStudy. Built for Kenyan medical and health students to revise key concepts and prepare for exams.
Q1. A study of blood product therapy is done. One product is identified that carries the greatest risk for infection. This blood product has the shortest shelf life, and it must be used as quickly as possible for transfusion. Which of the following products is best described by these findings? Options: A) Platelets
Answer: Whole blood
Explanation: Platelets are stored at room temperature (not refrigerated), have the shortest shelf life (5 days), and highest bacterial contamination risk due to room temperature storage. ---
Q2. A 17-year-old boy has developed a mild fever with sore throat over the past day. On physical examination he has generalized lymphadenopathy. Laboratory studies show a CD4 lymphocyte count of 375/microliter. He is most likely to be infected with which of the following agents? Options: A) HTLV-1
Answer: HTLV-2
Explanation: HTLV-1 can cause adult T-cell leukemia/lymphoma with lymphadenopathy and can affect CD4 counts. The acute presentation with lymphadenopathy fits HTLV-1 infection better than the other options. ---
Q3. A healthy 27 year old male donates blood. He completes the questionnaire and interview with no exclusions noted. The presence of which of the following infectious agents will not routinely tested for on his blood collected for transfusion? Options: A) Human immunodeficiency virus type 1
Answer: Hepatitis A virus
Explanation: Hepatitis A is not routinely tested in blood donors because it's primarily fecal-oral transmission, has short viremic period, and doesn't cause chronic infection. All other agents are routinely screened. ---
Q4. During phlebotomy, there is difficulty obtaining blood for all of the test ordered. Not all of the collection tubes are completely filled. Of the following collection tubes, which is the only one that may be partially filled and not affect test results? Options: A) Gray top for glucose
Answer: Red top for total protein
Explanation: Red top tubes (serum tubes) don't contain anticoagulants, so the blood-to-additive ratio isn't critical. Other tubes require specific ratios for accurate results (especially coagulation studies). ---
Q5. A 25-year-old woman incurs a head injury from a skiing accident. She is now in stable condition and her vital signs are normal. Serum electrolytes now show Na 134 meq/L, K 7.6 meq/L, Cl 100 meq/L, and CO2 25 meq/L. What is the most likely etiology for these laboratory test findings? Options: A) Hemolyzed specimen
Answer: Severe diarrhea
Explanation: Stable patient with markedly elevated potassium (7.6) but normal other electrolytes suggests pseudohyperkalemia from hemolysis during blood collection, releasing intracellular potassium. ---