352: Chorionic-vasculitis is associated with more intense fetal and intraamniotic inflammatory-responses in the context of amnionitis

Abstract

Inflammation or necrosis in amnion is an intermediate or advanced stage of maternal inflammatory response while chorionic vasculitis is an early stage of fetal inflammatory response(FIR) in ascending intrauterine infection(AIUI). Of note, both amnionitis and chorionic vasculitis have been regarded as the same stage III in the conventional process of AIUI. However, we cannot find any information about the comparison in the intensity of FIR and intraamniotic inflammatory response(IAIR) between chorionic vasculitis and amnionitis. The objective of current study is to examine whether the presence of chorionic vasculitis is associated with more intense FIR and IAIR even in the context of amnionitis. FIR and IAIR were examined according to the presence or absence of chorionic vasculitis in 82singleton preterm birth(≤35.5wks) due to either PTL or preterm-PROM in the context of amnionitis. FIR was determined by umbilical cord(UC) plasma CRP concentration at birth, the frequency of fetal inflammatory response syndrome(FIRS; defined as UC plasma CRP at birth≥200ng/ml), and the progression of inflammation in UC(i.e., inflammation-free UC, inflammation restricted to umbilical vein[UV], inflammation in at least one umbilical artery[UA] without extension into Wharton’s jelly, the extension of inflammation into WJ). IAIR was assessed by MMP-8 concentration in 37amniotic fluid(AF) samples obtained within 3days of birth. Chorionic vasculitis was present in 21% of cases with amnionitis. Median UC plasma CRP level at birth(Fig.1[a]) and the frequency of FIRS(Fig.2[a]) were higher, and the progression of inflammation in UC was more advanced(Fig.2[b]) in cases with chorionic vasculitis than in those without chorionic vasculitis. Moreover, cases with chorionic vasculitis had a higher median AF MMP-8 level than those without chorionic vasculitis(Fig.1[b]). Chorionic vasculitis is associated with more intense FIR and IAIR even in the context of amnionitis. This finding suggests that amnionitis and chorionic vasculitis should not be regarded as the same stage in the process of AIUI.View Large Image Figure ViewerDownload Hi-res image Download (PPT)