Influence of spurious dilution and hyperglycemia on erythrocytes and platelets evaluated with two different hematological analyzers

The integrity of whole blood samples may be compromised by suboptimal collection practices. Therefore, we investigated the influence of spurious hyperglycemia on erythrocytes and platelets, assessed with two hematological analyzers using optical or impedance technique. Three K2EDTA blood specimens were collected from 12 healthy subjects, pooled and divided into four aliquots. The first aliquot was left untreated (glucose concentration 4.4 mmol/L), whereas scalar amounts of standard 5% glucose solution were added to the remaining, generating glucose contamination of 5% (19.2 mmol/L), 10% (33 mmol/L) and 20% (62 mmol/L). Hematological testing was then performed using Siemens Advia 2120 and Sysmex XE-2100, whereas glucose and cell-free hemoglobin were measured in centrifuged plasma. Hemolysis did not occur in contaminated aliquots, whereas hemoglobin, erythrocyte count, hematocrit, mean corpuscular hemoglobin concentration and platelet count progressively decreased with glucose concentration. No clinically significant variation was found for red blood cell distribution width and mean corpuscular hemoglobin. The erythrocyte size increased in parallel with glucose, exhibiting larger variation with Advia 2120 than with XE-2100. The mean platelet volume increased on Advia 2120 but not on XE-2100. These results suggest that hyperglycemia induces alterations of erythrocyte and platelet properties, which differ according to the technology used for assessment.