Transverse colon tuberculosis presenting as colonic obstruction.

To the Editor: A 21-year-old woman presented with a history of abdominal pain, occasional vomiting, and fever of 2 weeks’ duration. She had no respiratory symptoms, and her past history was unremarkable. On examination she had a low-grade fever and mild tenderness in the abdomen. No masses were felt in the pelvis. Her white cell count was 3.7×10/l, and blood culture was negative. The chest radiograph was unremarkable. Computed tomography (CT) of the abdomen showed a remarkable omental thickening, with nodularity with ascites (Fig. 1). The level of the tumour marker CA-125 was 7 988 kU/l (normal 0 35), and the level of carcino-embryonic antigen was normal. At diagnostic laparoscopy, multiple seedlings were seen on the peritoneum. Peritoneal biopsy was negative for malignancy, acid-fast bacilli and Mycobacterium tuberculosis (MTB) complex DNA. The ascitic fluid also was negative for MTB complex DNA and for malignant cells. Histopathological examination of the peritoneal biopsy showed a chronic inflammatory infiltrate resembling tuberculosis. The patient was put on antituberculosis treatment, improved and was discharged. Peritoneal tuberculosis may be misdiagnosed as peritoneal carcinomatosis, as the two conditions share many radiological and clinical features, especially when serum CA-125 levels also are elevated. CA-125 is a useful marker of ovarian epithelial malignancy. It is secreted by mesothelial cells of the pleura, peritoneum and pericardium. Its levels can rise in conditions with serosal involvement by tuberculosis, leukaemia and lymphoma. Acid-fast bacilli were not seen in the ascitic fluid and tissue specimen in our patient. The diagnosis was made by histopathology. This case reminds us that in any case of ascites with elevated serum CA-125 level tuberculosis should be considered in the differential diagnosis. It has been reported that CA-125 can be used to monitor the response to antituberculosis treatment.