Marked interference of hyperglycemia in measurements of mean (red) cell volume by Technicon H analyzers

Severe hyperglycemia can result in falsely high results for mean cell (erythrocyte) volume (MCV), which will also cause false results for erythrocyte indices calculated on the basis of MCV. Falsely high MCV results were obtained with the Technicon H1 and H2 analyzers and (to a lesser extent) with the Coulter T660. The H analyzers were more susceptible to this interference than was the Coulter T660. This difference in sensitivity of MCV to hyperglycemia can be explained by the use of sodium dodecyl sulfate in the Technicon erythrocyte diluent and by differences in incubation times. In severe hyperglycemia, results for MCV, mean cell hemoglobin concentration, and hematocrit obtained from electronic cell counters, especially Technicon H systems, are unreliable.