Am J Perinatol 1990; 7(2): 130-132
DOI: 10.1055/s-2007-999463
ORIGINAL ARTICLE

© 1990 by Thieme Medical Publishers, Inc.

Leukocyte Esterase Activity in Amniotic Fluid: Normal Values During Pregnancy

Iffath Abbasi Hoskins, Frances Marks, Steven Anthony Ordorica, Bruce Kenneth Young
  • Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, New York University-Bellevue Medical Center, New York, New York
Further Information

Publication History

Publication Date:
04 March 2008 (online)

ABSTRACT

Chorioamnionitis during pregnancy is a common diagnostic dilemma for the obstetrician. Fast and accurate diagnosis poses the most significant problem. Since leukocytes are known to be released in response to infections, examination ofamniotic fluid for their presence is an important part of the evaluation for chorioamnionitis. These neutrophils contain several esterases that are not present in serum, urine, or vaginal secretions. The esterases are not influenced by bacteria or by commonly used drugs. We have previously described the reliability of leukocyte esterase (LE) activity for the detection of chorioamnionitis in term pregnancies uncomplicated by other diseases. A prospective study was performed to assess the presence or absence of LE activity to establish normal values in amniotic fluid at various gestational ages prior to term before its use as a possible predictor for chorioamnionitis. Sterile amniotic fluid specimens were obtained from 13 patients undergoing second trimester genetic amniocentesis (with gestational ages varying from 15 to 19 weeks) and from 11 patients with a wide variety of medical problems, undergoing amniocentesis for Rh sensitization or lung maturation studies (with gestational ages ranging from 25 to 27 weeks). All patients with ruptured membranes or preterm labor were excluded. Each amniotic fluid sample was divided into two parts, one of which was transported to the laboratory for aerobic and anaerobic cultures and the other used for LE activity detection as measured by dipstick. The LE results were retrospectively compared with the results of the cultures. LE activity was always found to be negative when the culture results were negative. On the basis of this study, we have established the norms for LE activity in amniotic fluid prior to term, even in the presence of other medical or obstetric complications.

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