Clinical chorioamnionitis at term II: the intra-amniotic inflammatory response

Area of Science:

• Reproductive Medicine
• Immunology
• Obstetrics

Background:

• Clinical chorioamnionitis is a complex condition with varying bacterial presence and inflammation levels in the amniotic cavity.
• Understanding the inflammatory profile is crucial for accurate diagnosis and management of term chorioamnionitis.

Purpose of the Study:

• To characterize the amniotic fluid's inflammatory response in term clinical chorioamnionitis.
• To differentiate inflammatory patterns based on the presence or absence of bacteria and intra-amniotic inflammation.

Main Methods:

• A retrospective case-control study analyzed amniotic fluid (AF) cytokine and chemokine concentrations in 45 women with term clinical chorioamnionitis and 24 controls.
• Patients were classified based on AF cultures, PCR-MS, and IL-6 levels into groups with/without inflammation and/or bacteria.
• V-PLEX immunoassays measured 29 cytokines/chemokines in AF.

Main Results:

• Women with chorioamnionitis had significantly higher AF pro- and anti-inflammatory cytokines/chemokines (e.g., IFN-γ, TNF-α, IL-4, MIP-1β, IL-8) than controls.
• Both microbial-associated and non-microbial intra-amniotic inflammation showed distinct cytokine/chemokine profiles compared to uncomplicated pregnancies.
• No significant difference in inflammatory response patterns was observed between chorioamnionitis with and without detectable bacteria.

Conclusions:

• Term clinical chorioamnionitis with or without detectable bacteria involves a significantly upregulated intra-amniotic inflammatory response.
• A subset of patients diagnosed with chorioamnionitis lacks intra-amniotic inflammation, indicating potential over-diagnosis.
• This study provides the first characterization of the cytokine/chemokine network in the amniotic cavity during term clinical chorioamnionitis.