What can cause a falsely low hemoglobin reading?

A falsely low hemoglobin reading can occur due to the presence of hemolysis in the sample or fluid overload, both of which can interfere with the accurate measurement of hemoglobin.

When hemolysis happens, red blood cells break down, releasing their contents, including hemoglobin, into the plasma. This can lead to an artificially lower hemoglobin concentration when performing laboratory tests, as the hemolysed sample can alter the optical density readings or interfere with the measurement methods used in automated analyzers. In cases of fluid overload, the dilution of blood components results in reduced concentrations of red cells and hemoglobin, thus yielding a lower hemoglobin result.

In contrast, insufficient iron intake typically leads to iron deficiency anemia, which would cause a genuinely low hemoglobin level rather than a falsely low reading. Dehydration concentrates the blood components, which tends to increase hemoglobin levels rather than decrease them. A low leukocyte count does not directly impact hemoglobin measurements, as leukocytes do not contribute to hemoglobin concentration in the same way red blood cells do. Thus, understanding these mechanisms is key in hematology and laboratory diagnostics.