Abdominal cocoon syndrome caused by Mycobacterium bovis from consumption of unpasteurised cow's milk

Abstract

A 12-year-old girl presented to the emergency room with severe abdominal pain, non-bilious emesis, and a 3-month history of progressively worsening lower abdominal pain, malaise, night sweats, and 4 kg weight loss. She had emigrated from Iraq 2 years earlier, and had been fed cow’s milk—often taken directly from the udder—after birth because her mother was unable to breastfeed. In the emergency room, her lower abdomen was tender, without peritonitis, and distended. Her white blood cell count, erythrocyte sedimentation rate, and C-reactive protein concentration were raised, whereas tests for hepatitis A, B, and C, HIV, and tuberculosis were negative. MRI of her abdomen and pelvis revealed extensive thickening of the bowel mesentery, peritoneum, and greater omentum, with a complex right-sided adnexal mass (appendix). We did an exploratory laparotomy to assess the mass, and encountered a dense, thick rind of tissue that was studded with tubercles and encased the peritoneal cavity (fi gure). A diagnosis of abdominal cocoon syndrome was made, and the abdomen was closed due to the extreme diffi culty in separating the fi brotic tissue from the abdominal wall. Frozen-section biopsy samples revealed caseating granulomas consistent with tuberculosis. A culture of the peritoneal fl uid grew Mycobacterium bovis subspecies bovis after 4 weeks and was resistant to pyrazinamide. The girl stayed in hospital for 3 months because she had recurrent episodes of partial or complete bowel obstruction that resolved with conservative, non-operative management. She was given isoniazid, rifampicin, and moxifl oxacin for 6 months while in hospital, followed by isoniazid and rifampicin for a further 12 months. On her last follow-up visit, she was no longer receiving antibiotic therapy, and was functioning normally. No further surgical intervention was planned for her, even though a repeat MRI of her abdomen and pelvis continued to show the thickened peritoneum and adnexal mass.