Esterase activity in second- and third-trimester amniotic fluid: an indicator of chorioamnionitis

Area of Science:

• Obstetrics and Gynecology
• Clinical Chemistry
• Infectious Diseases

Background:

• Chorioamnionitis diagnosis presents significant clinical challenges.
• Previous research indicated leukocyte esterase activity in amniotic fluid as a potential diagnostic aid.
• Dipstick assays for esterase activity showed promise but lacked optimal accuracy.

Purpose of the Study:

• To evaluate the effectiveness of an in vitro spectrophotometric assay for amniotic fluid esterase activity.
• To establish baseline esterase activity levels in uninfected amniotic fluid.
• To compare the diagnostic reliability of the spectrophotometric assay against dipstick and culture methods.

Main Methods:

• Fifty-seven amniotic fluid samples were collected during second- and third-trimester amniocenteses.
• Samples were divided for microbial culture, dipstick esterase assay, and spectrophotometric esterase assay.
• Spectrophotometric assay measured quantitative esterase activity, defining baseline and elevated levels.

Main Results:

• The spectrophotometric assay demonstrated higher specificity and sensitivity in detecting elevated esterase activity.
• A quantitative increase in esterase activity was observed in infected amniotic fluid samples.
• The spectrophotometric method proved more reliable in predicting chorioamnionitis than dipstick or culture.

Conclusions:

• The in vitro spectrophotometric assay is a more reliable tool for diagnosing chorioamnionitis.
• This method offers improved accuracy in identifying elevated esterase activity associated with infection.
• Spectrophotometric analysis provides a quantitative and sensitive approach to aid in chorioamnionitis diagnosis.