Determination of Hematologic Reference Values of Neonates in Mashhad - Iran

The results of laboratory tests have little practical utility unless clinical studies have ascribed various states of health and disease to intervals of values. Several factors affect hematologic values, including race, environment, time of sampling, test method, blood collection site, gestational age and maternal factors. Since these factors vary in various populations, they can cause differences in reference hematologic values. Between September 2007 and March 2008, 447 healthy neonates with more than 2500 g weight were selected and cord blood specimen was taken using EDTA as the anticoagulant. Complete blood count, hemoglobin, hematocrit, and RBC indices were measured by Sysmex cell counter. Differential leukocyte counts were determined in peripheral blood smear. Data were analyzed by SPSS software (version 11.50). A p value < 0.05 was considered to be significant. Mean values and reference ranges of hematologic parameters were as follows: WBC (x10μl)= 11.62 (5.16-18.2), RBC (x10 μl)= 4.45 ( 3.61-5.29), Hb (g/dl)=15.9 (13-18.8), Hct (%)= 48.3 (39.6-56.9), MCV (fl)= 108.7 (97.5-119.8), MCH (pg)= 35.8 (31.7-40), MCHC (g/dl)= 33 (30.135.2), RDW (%)= 17.1 (14.1-20.3). We observed some differences in hematologic values of neotanal cord blood in comparison with other references which are in use in daily clinical practice. Especially RBCs and hemoglobin were higher and MCV, WBC and absolute neutrophil count were lower.