Evaluation of diagnostic value of lamellar body counts (LBC) in amniotic fluid for diagnosis of neonatal respiratory distress syndrome (RDS) in pregnancy termination at 28-40 gestational weeks

Respiratory distress syndrome (RDS) due to lack of enough surfactant in fetal lung tissue is one of the common causes of neonatal mortality. There are several laboratory methods to determine the amount of fetal lung surfactant. The purpose of this study is to assess the lamellar body count for prediction of the amount of pulmonary surfactant for diagnosis of neonatal respiratory distress syndrome in premature neonates. This cross-sectional and applied study was performed on 91 infants with gestational age between 28-40 weeks for 6 months in 2013. In this study، lamellar body count test was performed for all infants. Lamellar body count was performed by a cell counter (Sysmex model K-X21). ROC Curve was also used for data analysis. Among 91 samples، 14 cases (15. 4%) had respiratory distress syndrome. There were significant relationship between the prevalence of respiratory distress and gender (P=0. 05)، gestational age (P=0. 01) and neonatal weight (P=0. 01). The best cut off point for lamellar body count was less or more than 22500. Also، sensitivity، specificity، positive and negative predictive values were 94. 7%، 100%، 100% and 94. 7%، respectively. Lamellar body count is a useful test for screening in terms of neonatal pulmonary surfactant. The test has appropriate sensitivity and specificity in the diagnosis of respiratory distress syndrome.