Complex Rectovesical and Rectourethral Fistulas: Integrating Anatomical Assessment, Individualized Surgical Reconstruction, and Multidisciplinary Management

Complex rectovesical and rectourethral fistulas represent uncommon but challenging pathological communications between the gastrointestinal and urinary systems, frequently associated with previous pelvic surgery, radiotherapy, malignancy, trauma, and inflammatory conditions. Their management requires comprehensive anatomical evaluation, individualized surgical planning, and multidisciplinary collaboration to achieve durable closure while preserving urinary and gastrointestinal function. This narrative review aimed to analyze the anatomical, diagnostic, and reconstructive characteristics of complex rectovesical and rectourethral fistulas, emphasizing surgical decision-making, postoperative outcomes, and current limitations in the scientific evidence. A structured thematic synthesis of international biomedical literature was developed, incorporating systematic reviews, observational investigations, multicenter studies, and relevant reconstructive reports, including contributions from Latin America. The analysis addressed etiological mechanisms, anatomical assessment, diagnostic imaging, surgical approaches, vascularized tissue interposition, and functional recovery. The reviewed evidence demonstrated substantial heterogeneity in fistula characteristics, reconstructive techniques, and definitions of surgical success. A previously published systematic review involving 416 patients reported an overall surgical closure rate of 87.5%, although differences in patient selection and operative strategies limited direct comparisons. Transperineal reconstruction and gracilis muscle interposition were frequently described in complex rectourethral defects, while transabdominal, transsphincteric, robotic-assisted, and endoscopic approaches demonstrated specific anatomical applications. Multidisciplinary assessment emerged as an important component of reconstructive planning, particularly in patients with previous irradiation, extensive fibrosis, or recurrent fistulas. Anatomical closure did not consistently correspond to complete functional recovery, emphasizing the importance of evaluating urinary continence, bowel function, complications, recurrence, and quality of life. Current evidence remains limited by heterogeneous study designs and insufficient standardization of postoperative outcomes. Comprehensive anatomical characterization, individualized reconstructive selection, and coordinated multidisciplinary management constitute essential principles for addressing complex urinary–rectal fistulas. Further multicenter investigations are necessary to strengthen comparative evidence and establish standardized clinical and functional outcome measures.