ABSTRACT
OBJECTIVE: Results of antepartal fetal lung maturity (FLM) testing in diabetics were compared to control patients. We analysed 274 patients by phospholipid profile and 219 by phosphatidylglycerol (PG), consisting of 73, respectively 54 diabetic and 201, resp. 165 normal control subjects. MATERIAL AND METHODS: Phospholipid concentration increased exponentially with gestational age (rreg = 0.44 for diabetic and 0.57 for normal control patients). There was no significant difference between both groups. Measurement of PG showed a trend towards lung immaturity in diabetic infants for preterm and term gestations, which did not reach significance (chi-square [chi 2] test 0.07, resp. 0.06). RESULTS: Diabetic and non-diabetic pregnancies did not differ significantly in FLM and RDS frequency. Both methods show a high rate of falsely immature results. Antepartal FLM testing by measurement of phospholipids and PG does not play a role in clinical management of diabetic patients.
Subject(s)
Fetal Organ Maturity/physiology , Lung/embryology , Pregnancy in Diabetics/diagnosis , Respiratory Distress Syndrome, Newborn/diagnosis , Amniocentesis , False Positive Reactions , Female , Gestational Age , Humans , Infant, Newborn , Male , Phosphatidylglycerols/analysis , Phospholipids/analysis , Pregnancy , Pregnancy in Diabetics/physiopathology , Respiratory Distress Syndrome, Newborn/physiopathology , Risk Factors , Sensitivity and SpecificityABSTRACT
OBJECTIVE: Comparison of three different methods of fetal lung maturity (FLM) testing in amniotic fluid (AF) to predict fetal respiratory distress syndrome (RDS): phospholipid concentration, phosphatidylglycerol (PG) and lamellar body count (LBC). STUDY DESIGN: 315 amniotic fluid (AF) samples were tested, 291 by determination of phospholipid, 237 by PG and 68 by LBC. Eighty one patients (26%) delivered within 3 days, incidence of RDS was 7% (n = 6). Correlation of phospholipids and LBC to gestational age was analyzed as well as correlation of LBC and PG versus phospholipid concentration. Sensitivity and specificity for all three methods were calculated. RESULTS: Phospholipids and LBC increased exponentially with gestational age (rregr = 0.54, p < 0.01, rregr = 0.76, p < 0.01) showing a curvilinear function. There was a linear correlation between both methods (rcorr = 0.51, p < 0.01, n = 47). Sensitivity for prediction of RDS was 80% for phospholipids compared to 83% for LBC and 67% for PG. Specificity was best for PG (92%) followed by phospholipids (85%). While positive predictive value was low (27% for phospholipids and 50% for LBC), negative predictive value varied between 97% and 100%. CONCLUSIONS: LBC is a simple and reliable method for FLM testing, with a sensitivity comparable to phospholipid testing and a somewhat lower specificity (67% vs. 85%). It may be useful for screening of FLM in a cascade approach.