Clinical Testing & Analysis Flashcards

Which of the following tests is most commonly used to assess kidney function in a clinical laboratory?

Answer: Creatinine

Creatinine is a waste product generated from muscle metabolism that is consistently filtered out of the blood by the kidneys. Measuring serum creatinine levels is the most common and reliable laboratory test to assess kidney function because it directly reflects the glomerular filtration rate (GFR). Elevated creatinine levels typically indicate impaired kidney function, as the kidneys are not effectively removing this waste product.

What is the primary purpose of performing a Complete Blood Count (CBC) test?

Answer: Evaluate blood cell components

A Complete Blood Count (CBC) is a comprehensive blood test that provides vital information about the different types of cells in the blood: red blood cells, white blood cells, and platelets. It evaluates their numbers, sizes, and characteristics, helping to diagnose a wide range of conditions. These include anemia, infections, inflammation, and bleeding disorders, making it a fundamental diagnostic tool.

Which test is most appropriate for diagnosing diabetes mellitus?

Answer: Hemoglobin A1c

The Hemoglobin A1c test measures the average blood glucose levels over the past two to three months by quantifying the percentage of hemoglobin in red blood cells that is glycated. This provides a long-term picture of glucose control, making it a highly effective and widely used diagnostic tool for diabetes mellitus. Unlike single-point glucose measurements, A1c is not affected by recent food intake and offers a more stable indicator of chronic hyperglycemia.

Which laboratory test is used to assess coagulation function?

Answer: Prothrombin Time (PT)

Prothrombin Time (PT) is a crucial laboratory test used to evaluate the extrinsic and common pathways of the coagulation cascade, which are essential for blood clotting. It measures the time it takes for plasma to clot after adding tissue factor, helping to diagnose bleeding disorders, monitor anticoagulant therapy (like warfarin), and assess liver function. An elevated PT indicates a prolonged clotting time.

Which of the following is a key marker used to diagnose myocardial infarction?

Answer: Troponin

Troponin is a highly specific and sensitive biomarker for myocardial infarction (heart attack). When heart muscle is damaged due to ischemia, troponin proteins are released into the bloodstream. Elevated levels of cardiac troponin (T or I) indicate myocardial injury, making it the preferred diagnostic marker in clinical practice for confirming a heart attack.

Which of the following laboratory tests is commonly used to assess liver function?

Answer: Alanine Aminotransferase (ALT)

Alanine Aminotransferase (ALT) is an enzyme primarily found in liver cells. When the liver is damaged or inflamed, ALT is released into the bloodstream, causing its levels to rise. Measuring serum ALT is a common and effective test for assessing liver function and detecting liver injury, as elevated levels are a strong indicator of hepatocellular damage.