Elevated CHI3L1 and COX-2 levels correlate with menstrual pain severity in endometriosis

Endometriosis is a chronic gynecological disease associated with inflammation and severe pelvic pain in 6%-10% of women of reproductive age. Although the pathophysiology and management of endometriosis are currently understood, further research is needed to develop new diagnostic methods, particularly those involving inflammatory pathways, which could guide targeted therapies. This study aims to analyze the differences in levels of Chitinase-3-like protein 1 (CHI3L1) and Cyclooxygenase-2 (COX-2) in the walls of endometriosis cysts compared to non-endometriosis cysts (controls) and to evaluate the correlation of CHI3L1 with COX-2 and menstrual pain level using the Visual Analog Scale (VAS).

This observational analytical study utilized a cross-sectional design and included 64 samples divided into 2 groups: 32 endometriosis cysts and 32 non-endometriosis cysts. Diagnosis is made through ultrasound and laparoscopic surgery or laparotomy, with histopathological confirmation. Samples were taken from the cyst walls and analyzed for CHI3L1 and COX-2 levels using the Enzyme-linked immunosorbent assay (ELISA) method. Statistical analysis was conducted using the Mann-Whitney test and Spearman's Rank correlation.

The results showed that CHI3L1 and COX-2 levels in the walls of endometriosis cysts were significantly higher than in controls (p < 0.001). A strong positive correlation was found between CHI3L1 and COX-2 (r_s = 0.767; p < 0.001) and between CHI3L1 and menstrual pain level (VAS) (r_s = 0.511; p = 0.003).

This study concludes that CHI3L1 may play a role in the pathogenesis of endometriosis through an inflammatory pain pathway involving COX-2 and prostaglandins.