Correlation of a simple biochemical marker and intraamniotic infection in patients with preterm premature rupture of membranes

ABSTRACT

Subclinical intramniotic infection has been associated with preterm labour and preterm premature rupture of membranes. Prompt diagnosis of subclinical intraamniotic infection is important in that it may prevent the maternal and neonatal morbidity associated with clinical chorioamnionitis. While amniotic fluid cultures are widely used to assess the microbiologic state of the amniotic cavity, results are not immediately available and are not capable of covering a wide range of organisms with different culture requirements. Rapid methods for detection of infection such as Gram stain and acridine orange stain of AF are insensitive. This study evaluated AF glucose concentration as an early parameter of intraamniotic infection. Amniocentesis for 40 patients with preterm PROM gestation was carried out. Cultures of AF for aerobic and anaerobic organisms as well as for Mycoplasma species was done. Gram stain of AF as well as AF glucose assay were correlated with culture results. AF glucose concentration with a cut off value <15 mg/dl has a sensitivity of diagnosing intraammniotic infection of 95.8%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 94.1%. AF glucose concentration is more rapid. simple, and non-expensive than the elaborate culture techniques. At the same time, it is more sensitive and reliable than Gram stain. Mycoplasma species had a big share in intraamniotic infection. Such organisms need specific culture requirements and are mostly invisible with Gram stain. AF glucose concentration has a particular advantage in that respect