Stability of blood cell counts, hematologic parameters and reticulocytes indexes on the Advia A120 hematologic analyzer

Delayed sample analysis is not a rare circumstance in clinical and laboratory practice, especially when blood samples are shipped to distant centralized laboratories, when the analysis can not be readily performed, or when retesting is appropriate. In this study we sought to evaluate the stability of conventional and new hematologic parameters in blood specimens stored for as long as 24 hours at 4°C. Of the 21 hematologic parameters tested with the use of the Advia 120 hematologic analyzer (Bayer Diagnostics), means for paired samples of specimens differed significantly over the 24-hour storage period for hematocrit, main corpuscular volume, percentage of macrocytes, platelet count, main platelet volume, reticulocyte count and percentage, and reticulocyte hemoglobin content (all P < .01). We noted no significant changes in the other parameters tested or in the white blood cell differential. The overall distribution of the immature reticulocytes fractions remained substantially unchange...