Reference values of reticulocyte counts in five age groups of healthy infants at Rawalpindi, Pakistan.

OBJECTIVES: To determine the reference range values of reticulocyte counts among various infantile age groups at tertiary care hospitals. METHODS: The descriptive cross-sectional study was carried out at the Haematology Department of the Armed Forces Institute of Pathology (AFIP), Rawalpindi, from March 2010 to March 2011. The sample size was 2000 which was equally distributed between males and females across five age groups. < 27 days Group I; 03 months Group II; 06 months Group III; 09 months Group IV; and 1 year Group V. Each group had 400 patients. Reticulocyte staining was used to calculate the percentage of reticulocyte in all the groups. SPSS 15 was used for statistical analysis. RESULTS: Gender had no effect on reticulocyte count in all the five groups. The average range of reticulocyte count was 5.1 to 7.5 in Group I, observed in 272 (68%) infants, with a mean value of 1.58 +/- 0.65. For all the remaining groups, 7.6 to 10 was the average range. The mean reticulocyte count value in Group II was 0.73 +/- 0.37, while the values were 0.83 +/- 0.44, 0.82 +/- 0.44 and 0.80 +/- 0.43 in Group III, Group IV and Group V respectively. A significant difference was seen between Group I and the remaining four (p < 0.05). CONCLUSION: Reference values of reticulocyte counts currently used in our region were somewhat different from those currently used.