Which statement best describes the two most common preanalytical interferences in clinical chemistry?

Which statement best describes the two most common preanalytical interferences in clinical chemistry?

• A. Coagulation and Separation
• B. Dilution and Concentration
• C. EDTA and Heparin
• D. Hemolysis and Lipemia

Answer: (D)

In clinical chemistry, what you’re measuring can be distorted by factors that sneak in before the analysis—the preanalytical stage. The two most common interferences are hemolysis and lipemia. Hemolysis occurs when red blood cells break open during blood collection or handling, releasing intracellular components like potassium and various enzymes into the serum or plasma. This can artificially raise or alter many test results and often flags samples as compromised. Lipemia, on the other hand, is a cloudy, milky appearance caused by high lipid levels in the blood; it scatters light and can bias spectrophotometric assays, leading to inaccurate readings even in samples that otherwise look normal. Proper venipuncture technique, gentle handling, and appropriate fasting or sample processing help minimize these issues; when lipemia is present, some labs may use alternate methods or lipid-clearing steps to obtain accurate results. Other options reflect collection additives or processing steps rather than the common preanalytical interferences. Anticoagulants like EDTA or heparin are chosen to prevent clotting but aren’t themselves the typical interferences seen in chemistry results; they can affect specific tests if used inappropriately. Coagulation or separation describes parts of processing rather than the interferences that most commonly skew chemistry measurements, and dilution or concentration aren’t the standard preanalytical factors tied to the majority of chemistry test distortions.

In clinical chemistry, what you’re measuring can be distorted by factors that sneak in before the analysis—the preanalytical stage. The two most common interferences are hemolysis and lipemia. Hemolysis occurs when red blood cells break open during blood collection or handling, releasing intracellular components like potassium and various enzymes into the serum or plasma. This can artificially raise or alter many test results and often flags samples as compromised. Lipemia, on the other hand, is a cloudy, milky appearance caused by high lipid levels in the blood; it scatters light and can bias spectrophotometric assays, leading to inaccurate readings even in samples that otherwise look normal. Proper venipuncture technique, gentle handling, and appropriate fasting or sample processing help minimize these issues; when lipemia is present, some labs may use alternate methods or lipid-clearing steps to obtain accurate results.

Other options reflect collection additives or processing steps rather than the common preanalytical interferences. Anticoagulants like EDTA or heparin are chosen to prevent clotting but aren’t themselves the typical interferences seen in chemistry results; they can affect specific tests if used inappropriately. Coagulation or separation describes parts of processing rather than the interferences that most commonly skew chemistry measurements, and dilution or concentration aren’t the standard preanalytical factors tied to the majority of chemistry test distortions.