The Counts Reference Ranges Of Neutrophils From Peripheral Blood And Primary Utility In Diagnosis Of Septicemia In Very-Low-Birth-Weight Infants

Objective:To build count reference ranges for neutrophils from peripheral blood,to analyze the influencing factors and primarily evaluate the utility in the diagnosis of septicemia in very-low-birth-weight(VLBW)infants.Methods: Clinic material on VLBW infants was collected with excluding that ones accompanied by perinatal and neonatal complication, the reference ranges for absolute total neutrophil count (ATN),absolute total immature neutrophil count (ATI) and proportion of immature neutrophils to total neutrophils (I/T) from peripheral blood were built and some perinatal and neonatal factors were analyzed by group comparison.Results:1. The peak value of total white blood cell count(WBC) occurred between 12 and 18 hours after birth with a upper limit of 24,000mm3/L .2. As for leukocyte differential count ,at birth, the neutrophil percentage of WBC was 0.63, and maintained the same proportion with lymphocyte percentage during 8 to 15 days. Afterward, the lymphocyte stably occupied a proportion of 0.603. Newly built ATN reference ranges showed a peak at about 10 hours after birth, with a upper limit of 19,000 /mm3 and a lower limit of 5,700/mm3. After 60 hours after birth, the ATN remained unchanged, with a upper limit of 8,200 /mm3 and a lower limit of 2,000/mm3.4. Respectively,only one case (3.3%) of ATI and I/T values obtained from the"normal"VLBW neonates was outside the previously abroad reference ranges.5. The VLBW infants of the females, single birth and earlier gestational age had significantly higher ATN counts (p<0.05).6. Among the three cases of definite neonatal septicemia in this study ,one case during the 60 hours after birth was demonstrated neutropenia, and the other two cases after 60 hours had neutrophilia associated with elevated ATI and I/T ratio.Conclusion:1. The domestic reference ranges for ATN differed from the abroad ones.2. The gender,number of childbirth during the same delivery and gestational age are demonstrated to be the influencing facotors on ATN;3. The utility of the reference ranges in the diagnosis of neonatal septicemia requires further study.