The effect of primary cytomegalovirus infection on fetal lung maturity indices

The aim of this study was to evaluate the impact of primary cytomegalovirus (CMV) infection on fetal pulmonary surfactant production as assessed by different tests for the diagnosis of fetal lung maturity (FLM) on amniotic fluid (AF). A cross-sectional cohort study. AF samples from 11 pregnant women with primary CMV infection were examined for FLM between the 26th and 37th week of gestation. Normal pregnancies (n = 11) were matched for gestational age at amniocentesis and at delivery, birth weight, Apgar score and gender sex. FLM was assessed by planimetric and stoichiometric lecithin to sphingomyelin ratio (L/S), phosphatidylglycerol (PG) presence and lamellar bodies count (LB). Maternal immunological parameters (T-cells, natural killer [NK] activity) were also considered. Mean planimetric L/S ratio (4.2+/-2.1 vs 2.3+/-0.7, P < 0.01) and LB count (42.6 x 10(3)+/-19.0 x 10(3) vs 16.8 x 10(3)+/-11.5 x 10(3), P < 0.004) were higher in controls when compared to CMV infected patients. Moreover, planimetric L/S ratio was higher in five CMV non-infected babies compared to six CMV-infected babies (3.1+/-1.3 vs 1.9+/-0.8, P < 0.05). When FLM was related to maternal immunological results, planimetric and stoichiometric L/S and LBs count were negatively correlated with CD8+ T-cells (r = -0.8, P < 0.05; r = -0.9, P < 0.05; r = -0.9, P < 0.01, respectively); LBs was also negatively correlated with CD14+ T-cells (r = -0.8, P < 0.03). In contrast, a positive correlation was found between stoichiometric L/S and NK activity (r = 0.9, P > 0.01). Maternal primary CMV infection impairs FLM indices as a possible result of reduced surfactant release and/or production. Significant correlations were found between immunity status of CMV-infected mothers and FLM tests.