Premature rupture of the membranes and amniotic infections--the significance of laboratory tests.

White blood cell count (WBC), C-reactive protein (CRP) and elastase alpha 1-proteinase inhibitor complex (E alpha 1 PI) have been determined in 85 women during pregnancy and after birth to assess their diagnostic value in case of amniotic infection syndrome (AIS). In ten patients clinically diagnosed AIS could be confirmed by histopathological examination, five patients who fulfilled the clinical criteria showed no histological signs of infection. E alpha 1 PI levels were found to be elevated to above 200 micrograms/l in nine patients with clinical and histological infection and remained below this value in all but one of the cases not showing signs of AIS. On the other hand, CRP concentrations were elevated in five out of these ten women, but also showed false-positive values in patients without AIS; leucocyte counts above 15,000/mm3 have been observed in only one case before delivery. The application of betamethasone led to a marked elevation of leucocyte concentrations. CRP levels were raised substantially after birth, whereas E alpha 1 PI remained unchanged under both conditions. It is suggested that all three parameters should be taken into consideration to increase diagnostic reliability in case of suspected amniotic infections.