Role of cystatin C levels as an inflammatory marker in predicting endometriosis

OBJECTIVE: Endometriosis is a common chronic inflammatory disease associated with infertility and pelvic pain. Diagnosis is based on the appearance of endometriotic lesions at the time of surgery. Our study aimed to determine whether cystatin C can be used as a predictor of endometriosis and to investigate its potential role in doing so. METHODS: The study included 45 patients with endometriosis between the ages of 18 and 40 years whose pathology results were compatible with endometriosis and were operated on, and a control group of 45 healthy women. These two groups were compared in terms of serum cystatin C levels, demographic-clinical characteristics, operation results, and other laboratory values. RESULTS: The cystatin C and hs-CRP levels of the endometriosis patients were found to be significantly higher than the control subjects (p<0.005). Whether the endometriosis disease could be detected for serum cystatin C levels was determined by the receiver operating characteristic analysis and the most appropriate positive cutoff value for cystatin C was found to be 5.14 ng/mL (86.7% sensitivity and 77.8% specificity). In the linear regression analysis, it was observed that the probability of endometriosis increased 2.5 times when cystatin C levels increased above the threshold value of 5.14 ng/mL (OR: 2.5; 95%CI 2.24–2.76). CONCLUSION: Our study shows that the serum cystatin C levels can be used as a guide for diagnosis in patients with advanced endometriosis. However, more research is needed to prove its reliability and accuracy in order to put it into practice.