Giant prolapsed uterine leiomyoma causing acute urinary retention and severe anemia: a case report and review of the literature

Introduction: Uterine leiomyomas are common benign tumors that rarely present with severe complications. Acute urinary retention (AUR) is an exceptional initial symptom from mechanical obstruction. Profound anemia without reported menorrhagia is also atypical, resulting from a giant, prolapsed fibroid undergoing ischemic necrosis, leading to surface ulceration and chronic blood loss. We report a case of a giant prolapsed leiomyoma presenting with this rare combination of AUR and severe anemia. Case presentation: A 44-year-old, para 6, woman presented with a 1-month history of AUR. Examination revealed a large, impacted vaginal mass; labs showed severe anemia (hemoglobin 7.1 g/dL). Imaging confirmed a 13 × 12 cm prolapsed uterine leiomyoma with necrotic foci. After transfusion, a combined abdomino-vaginal myomectomy was performed. A standard vaginal approach failed, necessitating an abdominal incision with an anterior colpotomy to ligate the pedicle, followed by vaginal delivery of the mass. Histopathology confirmed a benign leiomyoma, and the patient recovered fully. Clinical discussion: This case highlights considering uterine pathology in female AUR. The patient's retention was caused by a "cork-in-a-bottle" effect from the impacted fibroid. The severe anemia is explained by ischemic necrosis followed by surface ulceration and chronic hemorrhage from the prolapsed mass, a mechanism distinct from menorrhagia. The surgical management demonstrates the necessity of intraoperative adaptability. The innovative use of an anterior colpotomy via an abdominal approach provided safe access to the vascular pedicle after a standard vaginal approach failed, bypassing the distorted anatomy. Conclusion: This case underscores that giant leiomyomas should be in the differential for female AUR, especially with concurrent anemia. It clarifies the pathophysiology of severe anemia without menorrhagia from a prolapsed, necrotic fibroid. Finally, it champions surgical flexibility, showing how an innovative, combined abdomino-vaginal approach can overcome significant anatomical challenges to ensure a successful outcome.