Chorioamnionitis classification
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] ; Associate Editor(s)-in-Chief: Adnan Ezici, M.D[2]
Overview
Chorioamnionitis may be classified into several subtypes based on the presentation of the patient, the type of infiltrating cells, anatomical regions infiltrated by neutrophils (stage), and the intensity of inflammation (grade).
Classification
Chorioamnionitis may be classified into several subtypes based on the presentation of the patient, the type of infiltrating cells, anatomical regions infiltrated by neutrophils (stage), and the intensity of inflammation (grade).[1]
- Chorioamnionitis may be classified according to the absence or presence of clinical signs and laboratory findings into two groups: clinical chorioamnionitis, and subclinical/histologic chorioamnionitis.[2][3]
- Subclinical/histologic chorioamnionitis indicates the inflammation of the chorion, amnion, and placenta in the absence of clinical signs.
- Diagnosis of histologic chorioamnionitis is mainly based on the evaluation of pathology which might be confirmed by the presence of inflammatory cells within the fetal membranes.
- The presence of maternal fever, leukocytosis, maternal/fetal tachycardia, uterine tenderness, foul-smelling amniotic fluid, and preterm rupture of membranes (PROM) indicates the clinical chorioamnionitis.
- Subclinical/histologic chorioamnionitis indicates the inflammation of the chorion, amnion, and placenta in the absence of clinical signs.
- Chorioamnionitis may be classified into acute and chronic forms, depending on the type of infiltrating cells.[4]
- Acute and chronic chorioamnionitis indicate the infiltration of the fetal membranes by PMNs and monocytes, respectively.
- The staging of chorioamnionitis is based on the anatomical regions infiltrated by neutrophils.[1]
- Stage 1 represents the infiltration of chorion or subchorionic space by neutrophils.
- Stage 2 represents the infiltration of chorionic connective tissue and/or amnion or the chorionic plate by neutrophils.
- Stage 3 represents the necrotizing chorioamnionitis, indicates the edema and necrosis of the amniotic epithelium.
- The grading of chorioamnionitis is based on the intensity of inflammation.[1]
- Grade 1, mild to moderate inflammation, represent the infiltration of fetal membranes by small clusters of maternal neutrophils.
- Grade 2, severe inflammation, represents the presence of at least 3 chorionic microabscesses (cluster of neutrophils measuring ≥ 10 x 20 cells) or the presence of neutrophils of ≥ 10 cells in width that involve at least half of the subchorionic fibrin or one cycle around the membrane roll.
- The staging system might be more effective to establish the severity of inflammation than the grading system.[1]
References
- ↑ 1.0 1.1 1.2 1.3 Kim CJ, Romero R, Chaemsaithong P, Chaiyasit N, Yoon BH, Kim YM (October 2015). “Acute chorioamnionitis and funisitis: definition, pathologic features, and clinical significance”. Am J Obstet Gynecol. 213 (4 Suppl): S29–52. doi:10.1016/j.ajog.2015.08.040. PMC 4774647. PMID 26428501.
- ↑ Peng CC, Chang JH, Lin HY, Cheng PJ, Su BH (June 2018). “Intrauterine inflammation, infection, or both (Triple I): A new concept for chorioamnionitis”. Pediatr Neonatol. 59 (3): 231–237. doi:10.1016/j.pedneo.2017.09.001. PMID 29066072.
- ↑ Ericson JE, Laughon MM (March 2015). “Chorioamnionitis: implications for the neonate”. Clin Perinatol. 42 (1): 155–65, ix. doi:10.1016/j.clp.2014.10.011. PMC 4331454. PMID 25678002.
- ↑ Chi BH, Mudenda V, Levy J, Sinkala M, Goldenberg RL, Stringer JS (January 2006). “Acute and chronic chorioamnionitis and the risk of perinatal human immunodeficiency virus-1 transmission”. Am J Obstet Gynecol. 194 (1): 174–81. doi:10.1016/j.ajog.2005.06.081. PMID 16389028.
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