Diagnosis and Management of Clinical Chorioamnionitis

Abstract

Chorioamnionitis is a common complication of pregnancy associated with significant maternal, perinatal, and long-term adverse outcomes. Adverse maternal outcomes include postpartum infections and sepsis while adverse infant outcomes include stillbirth, premature birth, neonatal sepsis, chronic lung disease and brain injury leading to cerebral palsy and other neurodevelopmental disabilities. Research in the last two decades has expanded our understanding of the mechanistic links between intraamniotic infection and preterm delivery as well as morbidities of preterm and term infants. Recent and ongoing clinical research into better methods for diagnosing, treating and preventing chorioamnionitis is likely to have a substantial impact on short and long-term outcomes in the neonate. KeywordsChorioamnionitis; infection; pregnancy; management DefinitionChorioamnionitis or intraamniotic infection is an acute inflammation of the membranes and chorion of the placenta, typically due to ascending polymicrobial bacterial infection in the setting of membrane rupture. Chorioamnionitis can occur with intact membranes, and this appears to be especially common for the very small fastidious genital mycoplasmas such as Ureaplasma species and Mycoplasma hominis, found in the lower genital tract of over 70% of women [1]. Only rarely is hematogeneous spread implicated in chorioamnionitis, as occurs with Listeria monocytogenes [2]. When characteristic clinical signs are present, the condition is referred to as clinical chorioamnionitis or clinical intraamniotic infection. Although there is significant overlap between clinical and histologic chorioamnionitis, the latter is a more common diagnosis based on pathologic findings on microscopic examination of the placenta that encompasses clinically unapparent (sub-clinical) chorioamnionitis as well as clinical chorioamnionitis. Funisitis, also a histopathologic diagnosis, is the extension of infection or inflammation to the umbilical cord. Overall the definition of chorioamnionitis a Corresponding author for proof and reprints: Dr. Alan T. N. Tita (alan.tita@obgyn.uab.edu Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Epidemiology (incidence and risk factors)Overall, 1-4% of all births in the US are complicated by chorioamnionitis [2]; however, the frequency of chorioamnionitis varies markedly by diagnostic criteria, specific risk factors and gestational age [3][4][5][6][7]. Chorioamnionitis (clinical and histologic combined), complicates as many as 40-70% of preterm births with premature membrane rupture or spontaneous la...

Recent Developments and Current Issues in the Epidemiology, Diagnosis, and Management of Bacterial and Fungal Neonatal Sepsis

“…Chorioamnionitis is defined as a maternal fever > 38°C and two or more of the following: maternal leukocytosis > 15,000 cells/mm 3 , maternal tachycardia > 100 beats per minute, fetal tachycardia > 160 beats per minute, uterine tenderness, or a foul odor to the amniotic fluid. 5 Although maternal fever occurs in one in four or five laboring women who receive epidural anesthesia, histological or microbiologic chorioamnionitis rarely occurs in women with an isolated fever. 6 Surveillance of high-risk preterm infants at 20 academically affiliated neonatal intensive care units (NICUs) of the NICHD Neonatal Research Network (NRN) noted that between 14% and 28% of women with preterm deliveries at 22 to 28 weeks' gestation had clinical presentations consistent with chorioamnionitis.…”

Optimizing Treatment of Intra-amniotic Infection and Early-Onset Postpartum Endometritis: Advantages of Single-Agent Therapy

“…However, extended-spectrum cephalosporins and penicillins and, more recently, carbapenems have also been shown to be effective singleagent treatments. 2,8 Studies comparing the effectiveness of the single-agent regimens to the standard, multidrug regimen of ampicillin-gentamicin-clindamycin did not show superiority of the single-agent treatments as these medications became available from 1980 to 2000. Because the cost of these newer medications was greater during that period, owing to patent protection, there was no compelling reason to consider routine use of these regimens over the standard treatment.…”

“…Clinically diagnosed infection is estimated to occur in 1% to 2% of full-term deliveries and in up to 10% of preterm deliveries 1 ; the rates are increased by premature rupture of membranes and cesarean delivery. 2 These polymicrobial infections require broad coverage for gram-positive, gram-negative, and anaerobic bacteria; added anaerobic coverage is beneficial when delivery is cesarean. The most commonly recommended antibiotic treatment regimen employs a combination of ampicillin, gentamicin, and clindamycin for patients not allergic to penicillin; the antibiotics used and the length of treatment vary with the route of delivery.…”

Low-grade intraventricular hemorrhage and neurodevelopment at 24 months of age

“…Chorioamniotitis was defined as an infection with resultant inflammation of any combination of the amniotic fluid, placenta, fetus, fetal membranes or decidua, with occurrence of rupture of membranes plus one or more of the following: maternal fever, mother's receipt of antibiotics antepartum, foul smelling amniotic fluid or uterine tenderness [19].…”