Abdominal tuberculosis with a Pseudo-Sister Mary Joseph nodule mimicking peritoneal carcinomatosis

Abstract

A 46-year-old woman presented in severe abdominal pain on a background of 3 months of weight loss and intermittent vomiting. She had visited East Africa 6 months prior but reported no unwell contacts. On examination, she had generalised abdominal tenderness, distension and a painful paraumbilical swelling. CT scanning confirmed small bowel obstruction and revealed widespread peritoneal nodules, lymphadenopathy, ascites and a soft tissue paraumbilical mass. CA-125 tumour marker was elevated. However, transvaginal ultrasound scanning showed normal-appearing ovaries. She underwent a diagnostic laparoscopy for ascitic fluid analysis and biopsy of omental and peritoneal nodules, which revealed a lymphocytic exudate and caseating granulomas, respectively. Interferon-γ release assay and repeated stains for acid-fast bacilli were negative. She was commenced on antituberculous chemotherapy for a presumed diagnosis of abdominal tuberculosis. Positive culture results 2 weeks later confirmed Mycobacterium tuberculosis infection. The patient experienced a complete resolution of symptoms within 6 weeks of treatment.