LAUSR

Uterine fibroids, the most common tumors in reproductive-aged women, are found in 20%-30% of women aged ≥ 30 years.1 However, they rarely become symptomatic after menopause, and emergency operation is usually unnecessary.2 Herein, we report a rare case of uterine fibroid torsion in a 60-year-old postmenopausal woman. The patient presented to an emergency department with a history of intermittent diffuse lower abdominal pain that started 3 days earlier. Previously, she had no episodes of vomiting, diarrhea, or vaginal bleeding. Upon examination, she was afebrile and tachycardiac (103 beats/min) and had diffuse lower abdominal tenderness with peritoneal signs. Laboratory testing revealed a white blood cell count of 9.6 (normal 3.5-9.1) x 109/l and a C-reactive protein level of 117 (normal 0-3) mg/l. Peritonitis was suspected, and pelvic and abdominal contrast-enhanced computed tomography (CT) showed a mass cranial to the uterus with a dark fan sign but no sign of appendicitis or other bowel etiologies (Figure 1a-c). Emergency transvaginal ultrasonography revealed a pelvic mass suggestive of a uterine fibroid (Figure 1d). Pelvic magnetic resonance imaging also suggested a uterine fibroid (Figure 1e) and confirmed bilateral intact ovaries, excluding the possibility of ovarian torsion. Signs of peritonitis and imaging findings indicated uterine fibroid torsion. Interoperative examination confirmed the diagnosis of necrotic pedunculated subserous uterine fibroid twisted by 360° with slight bleeding (Figure 2a). Given the prominent intrapelvic inflammation and strong edematous change to the uterus, hysterectomy was avoided to minimize the risk of unnecessary complications due to heavy bleeding. Necrotic fibroid myomectomy was successfully performed, and no postoperative complications were observed. Histology confirmed a benign necrotic leiomyoma with no sign of malignancy (Figure 2b). 1Department of Obstetrics and Gynecology, Suwa Central Hospital, Nagano, Japan 2Department of Medical Education Studies, International Research Center for Medical Education, Graduate School of Medicine The University of Tokyo, Tokyo, Japan 3Department of Internal Medicine, Suwa Central Hospital, Chino, Nagano, Japan So Yamashita1 , Hirohisa Fujikawa2,3 , Toru Yoshizawa1 A Rare Cause of Acute Abdomen: Torsion of Subserous Uterine Fibroid in a Postmenopausal Woman