Which finding is associated with a false increase in hemoglobin as well as the MCV and RBC count?

Which finding is associated with a false increase in hemoglobin as well as the MCV and RBC count?

• A. Marked leukocytosis
• B. Dehydration
• C. Polycythemia
• D. Iron deficiency anemia

Answer: (A)

A false elevation in these CBC indices often comes from a laboratory artifact caused by very high white blood cell counts. When leukocytosis is marked, automated hematology analyzers can misclassify or misread cells, and the extra cellular debris or turbidity can interfere with the measurements, causing the reported hemoglobin, hematocrit, RBC count, and even the calculated MCV to appear higher than they truly are. This isn’t a real increase in red cell mass; it’s an instrument/sample interference. In contrast, dehydration can raise the values through hemoconcentration but typically does not produce a consistent false rise in MCV, and iron deficiency anemia or true polycythemia would produce physiologic patterns consistent with those conditions rather than an artifact. If such a spike is suspected, repeating the test with a new sample and reviewing a peripheral smear help confirm whether it’s a true change or an instrument artifact.

A false elevation in these CBC indices often comes from a laboratory artifact caused by very high white blood cell counts. When leukocytosis is marked, automated hematology analyzers can misclassify or misread cells, and the extra cellular debris or turbidity can interfere with the measurements, causing the reported hemoglobin, hematocrit, RBC count, and even the calculated MCV to appear higher than they truly are. This isn’t a real increase in red cell mass; it’s an instrument/sample interference.

In contrast, dehydration can raise the values through hemoconcentration but typically does not produce a consistent false rise in MCV, and iron deficiency anemia or true polycythemia would produce physiologic patterns consistent with those conditions rather than an artifact. If such a spike is suspected, repeating the test with a new sample and reviewing a peripheral smear help confirm whether it’s a true change or an instrument artifact.