Project Summary/Abstract Urologic Chronic Pelvic Pain Syndrome (UCPPS) is a debilitating condition afflicting 10 million men and women in the U.S. UCPPS encompasses two highly prevalent chronic urologic pain disorders, interstitial cystitis/bladder pain syndrome (IC/BPS) in men and women, and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) in men. UCPPS prominently manifests as debilitating symptoms characterized by urinary urgency, frequency, and pain. Unfortunately, the biological mechanisms contributing to UCPPS symptoms remain unclear. This delays diagnosis and limits therapeutic development. Using a mass spectrometry-based metabolomics approach, we recently found that elevated urinary etiocholanolone sulfate (Etio-S) levels identify a high symptom score subgroup of female UCPPS patients. We hypothesize that elevated Etio-S is symptomatic of a more general perturbation of related steroids. We also hypothesize that this represents just one of multiple UCPPS subgroups arising from biochemically distinctive etiologies. In this study, we will use state-of-the-art targeted and untargeted metabolomics approaches to discern UCPPS- associated biochemical signatures in human specimens from the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) research network. Rigorous chemical identification will connect these results to specific physiological processes, providing the basis for new diagnostic and therapeutic approaches. Targeted metabolite assays of samples from these studies will be used to identify treatment-responsive subgroups in clinical trials, improving UCPPS patient care. An experienced interdisciplinary research team of physicians, analytical chemists, and mathematical data scientists has been assembled to ensure the rigor and clinical validity of this effort.