Amniotic-Fluid Lactoferrin: A Marker for Subclinical Intraamniotic Infection Prior to 32 Weeks Gestation

• Published in: Infectious Diseases in Obstetrics and Gynecology Vol. 1995; no. 5; pp. 179 - 183
• Main Authors: Heller, K A, Greig, P C, Heine, R P
• Format: Journal Article
• Language: English
• Published: Egypt Hindawi Limiteds 1995; Hindawi Publishing Corporation; Hindawi Limited
• Subjects: Preterm labor; decidual activation; chorioamnionitis
• ISSN: 1064-7449; 1098-0997
• DOI: 10.1155/S1064744995000573

Objective: Lactoferrin is a glycoprotein released from the secondary granules of activated neutrophils in the setting of infection. The purpose of this study was to determine if amniotic-fluid (AF) lactoferrin levels are elevated in preterm labor (PTL) patients with subclinical intraamniotic infection (IAI). Methods: AF samples were obtained from 186 pregnant patients with the following characteristics: group 1 - term, no labor; group 2 - preterm, no labor; group 3 - PTL with IAI; group 4 - PTL without IAI. Lactoferrin levels were measured with an enzyme-linked immunosorbent assay (ELISA). Results: AF lactoferrin levels were elevated in normal gestation after 31 weeks (P ＜ 0.0001). Lactoferrin levels were also higher in infected PTL patients compared with noninfected PTL patients at gestations ≤31 weeks (P = 0.005). An AF lactoferrin level of ＞2.5 μg/ml is highly suggestive of infection in PTL patients at ＜32 weeks, with an overall sensitivity of 82% and a specificity of 83%, when infection is defined as a positive AF culture or positive placental histology. Conclusions: AF lactoferrin levels increase after 31 weeks in normal gestations, but lactoferrin levels ＞2.5 μg/ml in PTL patients before this gestational age are highly suggestive of IAI. AF lactoferrin levels may be a useful clinical tool for selecting those PTL patients who might benefit from antimicrobial therapy, closer observation, or early delivery.