[Laboratory diagnosis of hyaline membrane disease and amniotic fluid inhalation. A study of 100 neonates with respiratory distress].

The aim of this study of 100 newborns with respiratory distress in the first 24 hours was to evaluate the diagnostic reliability of sequential L/S ratio testing of the fluid retrieved through tracheal suctioning in identifying hyaline membrane disease and that of calculating the urinary meconial index (UMI) for the first mictions in identifying amniotic fluid aspiration. The L/S ratio was found to be low (< 2) during the first 3 days in 90% of the cases of hyaline membrane disease; this good correlation shows that the technique employed here can reliably be used to diagnose clinically and radiologically atypical forms of this disease (12%). The UMI was found to be abnormally elevated (> 1) in all the cases of severe meconial aspiration. This result implies that minor or atypical cases or those in which another disorder is associated can be diagnosed by the test. It is therefore proposed that the concurrent use of these two tests would improve the accuracy of the etiological diagnosis of respiratory distress in newborns.