Thinking Outside the Lungs: A Case of Disseminated Abdominal Tuberculosis

BACKGROUND Extrapulmonary tuberculosis (TB) occurs in up to one-fifth of all cases of TB, with abdominal TB accounting for 5% of all cases. It is an uncommon diagnosis in the Western world, where it is primarily identified in immigrant and immunocompromised populations. CASE REPORT We review a case in which a 47-year-old Nepalese woman with a history of cognitive dysfunction secondary to epilepsy presented with decreased appetite and diffuse abdominal pain. She was hypoxic and febrile on initial exam, and imaging indicated lung consolidation, right-sided pleural effusion, and thickening and nodularity of the omentum with patchy wall thickening of the colon. After failing to improve on a standard antibiotic regimen for treatment of pneumonia and colitis, the differential was broadened to include TB. Interferon-g release assay was subsequently found to be positive, and omental and peritoneal biopsies were obtained. The patient was started on an empiric course of rifampin, isoniazid, ethambutol, pyrazinamide, and pyridoxine. Laboratory testing revealed no immunochemical evidence of Mycobacterium species, however, Ziehl-Neelsen acid-fast stain was positive with rare acid-fast bacilli identified. CONCLUSIONS Peritoneal TB carries significant morbidity and mortality if undiagnosed or untreated. Diagnosis is challenging in the absence of a single test that can confirm or exclude this condition. In combination with clinical suspicion, it is crucial to explore history regarding socio-epidemiology (travel, incarceration, occupation, homelessness, sick contacts) and immunological risk (drug use, chemotherapy) in patients with constitutional symptoms.