Elevated amniotic fluid nucleosome levels in women with intra-amniotic infection

Objective: To compare amniotic fluid (AF) soluble nucleosome levels in pregnant women with and without intraamniotic infection. Methods: Amniocentesis was performed in 74 pregnant women with preterm contractions, labor, or premature rupture of membranes. Intra-amniotic infection was defined as a positive AF culture. Amniotic fluid tests for Gram stain, glucose, neutrophils, creatinine, pH, and specific gravity were performed. Amniotic fluid soluble nucleosome levels were determined by enzyme-linked immunosorbent assay and were normalized by AF creatinine levels. Results: Twenty-eight patients had intra-amniotic infection and 46 did not. Amniotic fluid soluble nucleosome levels were significantly higher in pregnant women with intra-amniotic infection than in those without infection (48.1 ± 21.3 compared with 0.0 ± 0.0 U/mg creatinine; P = .005). The AF nucleosome levels were positively correlated with AF neutrophil counts and negatively correlated with AF glucose concentrations. Conclusion: Our data indicate that elevated AF nucleosome levels are associated with intra-amniotic infection and may have potential as a clinical marker to detect intraamniotic infection.