Stability of hematologic analytes in monkey, rabbit, rat, and mouse blood stored at 4°C in EDTA using the ADVIA 120 hematology analyzer

Background The time from sampling to analysis can be delayed when blood samples are shipped to distant reference laboratories or when analysis cannot be readily performed. Objective The objective of this study was to evaluate the stability of hematologic analytes in blood samples from monkeys, rabbits, rats, and mice when samples were stored for up to 72 hours at 4 degrees C. Methods Blood samples from 30 monkeys, 15 rabbits, 20 rats, and 30 mice were collected into EDTA-containing tubes and were initially analyzed within 1 hour of collection using the ADVIA 120 analyzer. The samples were then stored at 4 degrees C and reanalyzed at 24, 48, and 72 hours after collection. Results Significant (P <.0003) changes in hematologic analytes and calculations included increased HCT and MCV and decreased MCHC and cell hemoglobin concentration mean (CHCM) at 72 hours and increased MPV at 24 hours in monkeys; increased MCV at 72 hours and MPV at 48 hours and decreased monocyte count at 24 hours in rabbits; increased MCV and decreased MCHC, CHCM, and monocyte count at 24 hours in rats; increased MCV, red cell distribution width, and MPV and decreased MCHC, CHCM, and monocyte count at 24 hours in mice. Conclusions Although most of the changes in the hematologic analytes in blood from monkeys, rabbits, rats, and mice when samples were stored at 4 degrees C were analytically acceptable and clinically negligible, the best practice in measuring hematologic analytes in these animals is timely processing of blood samples, preferably within 1 hour after collection.