Interleukin-8 in urine: a new diagnostic parameter for intra-amniotic infection after premature rupture of the membranes.

Interleukin-8 (IL-8), a 72 amino acid peptide secreted by cells of the immune system and of the amnion, chorion and decidua, was measured in women in late pregnancy. IL-8 was detected in the urine of 91 of 104 women with premature rupture of the fetal membranes, with values exceeding 1000 ng/L in cases of severe intra-amniotic infection. Women with urinary tract infections were excluded. The routine measurement of IL-8 in urine, together with C-reactive protein in serum, thus provides a low risk and technically simple approach to the assessment of intra-amniotic infection.