Chorioamnionitis increases matrix metalloproteinase-8 concentrations in bronchoalveolar lavage fluid from preterm babies.

OBJECTIVE

To determine the effects of chorioamnionitis and antenatal corticosteroids on matrix metalloproteinase-8 (MMP-8) concentrations in bronchoalveolar lavage (BAL) fluid from preterm babies in the first week of life.

DESIGN

Prospective observational study.

SETTING

Regional neonatal intensive care unit.

PATIENTS: Thirty five ventilated preterm babies < 33 weeks gestation, seven of whom were born after chorioamnionitis, which was diagnosed histologically as the presence of inflammatory cells in the chorioamnionic plate.

METHODS

MMP-8 was measured by enzyme linked immunosorbent assay (ELISA) in 90 serial BAL samples taken during the first six postnatal days. The median MMP-8 concentration for each baby was calculated.

RESULTS

Median MMP-8 concentrations were higher in the chorioamnionitis group than in those without (43 v 5 ng/ml). Partial or complete courses of antenatal corticosteroids had no effect on MMP-8 concentrations.

CONCLUSIONS

Higher concentrations of MMP-8 are found in BAL fluid from preterm babies from pregnancies complicated by chorioamnionitis. This type I collagenase may contribute to the lung injury that occurs in some babies with respiratory distress syndrome.