Performance of hysteroscopy in diagnosing chronic endometritis and the role of intra- and inter-observer variability: a prospective study of 70 cases.

Introduction: Chronic endometritis (CE) is a persistent inflammation of the endometrium often implicated in female infertility. Histological examination with immunohistochemical (IHC) analysis of the plasma cell marker CD138 is the gold standard for diagnosing this condition. Methods: This prospective, multicentered, observational study was conducted from June 6, 2021, to August 8, 2022. We evaluated the diagnostic sensitivity and specificity of hysteroscopy (HSC) using the standardized criteria of Cicinelli et al, which include micro polyps, focal hyperemia, diffuse hyperemia, stromal edema, strawberry aspect, and hemorrhagic spots. We also assessed intra- and inter-observer variability in the hysteroscopic diagnosis of CE. Results: The prevalence of CE diagnosed by IHC analysis of CD138 expression was 42.9%. The performance of HSC in diagnosing CE was moderate, with a sensitivity of 47.5%, specificity of 64.38%, positive predictive value of 50%, and negative predictive value of 62.05%. The inter-observer agreement for hysteroscopic diagnosis of CE was strong ( Conclusion: HSC is not the examination of choice for diagnosing CE. An endometrial biopsy using the Novak curette with IHC analysis of CD138 expression is a more sensitive and less costly diagnostic method.