Association of endometriosis with interstitial cystitis in chronic pelvic pain syndrome: Short narrative on prevalence, diagnostic limitations, and clinical implications

Introduction: Chronic pelvic pain (CPP) is a diagnostic and therapeutic challenge affecting women of all ages globally. The syndrome is not well understood, but the association of interstitial cystitis (IC) with endometriosis in causing CPP should not be overlooked in managing this cohort. Herein, we present a mini review of this association to evaluate the literature in determining the prevalence of endometriosis and IC concomitantly in patients with CPP, diagnostic limitations, and clinical implications. Methods: A Medline search of the key words “evil twins’ syndrome,” “interstitial cystitis,” “bladder pain syndrome,” and “endometriosis” was conducted for full-text articles published in English over the past 20 years. The search yielded 40 articles, of which 21 were selected. Cross-referencing bibliographies of each publication yielded an additional 25 references. Results: Both endometriosis and IC share a similar array of symptoms that are often exacerbated during the perimenstrual period. Multiple authors have reported the frequent coexistence of these two conditions. Over 80% of patients with CPP were found to have both conditions. The prevalence of endometriosis and IC coexistence was greater than that of each condition separately. Conclusions: It is crucial to look beyond the traditionally diagnosed endometriosis as the cause of CPP. This is true especially in patients whose previous treatment was ineffective. Simultaneous assessment for both conditions is essential to avoid the frequently delayed diagnosis and prevent unsuccessful medical and surgical therapies.