Intestinal tuberculosis masquerading as difficult to treat Crohn disease: a case report

Abstract

BackgroundCrohn disease has low prevalence in Sri Lanka while compared to the West, while intestinal tuberculosis is common in the region. Since clinical, endoscopic and investigation features of Crohn disease overlap with intestinal tuberculosis, differentiating these two conditions becomes a dilemma for the clinician in the intestinal tuberculosis endemic setting.Case summaryAn 18-year old Sri Lankan Muslim female presented with chronic abdominal pain and weight loss. Colonoscopy revealed an ulcerated ileocaecal valve and a terminal ileal stricture. Biopsy confirmed Crohn disease with no supportive features to suggest intestinal tuberculosis. Despite treatment with adequate immunosuppression she failed to improve and underwent a limited right hemicolectomy and terminal ileal resection. Histology confirmed intestinal tuberculosis and she made full recover with 6 months of anti-tuberculosis treatment.ConclusionThis case illustrates the importance of reviewing the diagnosis to include intestinal tuberculosis in an endemic setting, when already diagnosed Crohn disease is treatment refractory.

A Comprehensive Review of Infectious Granulomatous Diseases of the Gastrointestinal Tract

“…Clinicians may find themselves attempting to diagnose ITB without these results [ 6 , 12 ]. When ITB granulomas are seen, they are multiple, large, confluent, and caseating, as seen in Figure 1 [ 19 , 20 ]. Five or more granulomas per ten low power fields or a diameter greater than 400 micrometers favors ITB [ 20 ].…”

“…Five or more granulomas per ten low power fields or a diameter greater than 400 micrometers favors ITB [ 20 ]. Other studies suggest that granulomas greater than 500 micrometers in size and the presence of ten or more granulomas accurately indicated a diagnosis of ITB [ 19 , 21 ]. Other features such as epithelioid histiocyte lined ulcers, submucosal granulomas, lymphocyte cuffing, and excessive submucosal inflammation favored ITB over CD [ 13 , 21 ].…”

“…In the absence of confirmatory testing or if the diagnosis is still equivocal, then as a last resort, a therapeutic trial of anti-TB medication may be warranted, and clinical response can be monitored [ 6 ]. This approach is considered safe, as the misdiagnosis of ITB as CD and treatment with steroids can be fatal [ 19 ]. Treatment principles of ITB have been inferred from the treatment of pulmonary TB with the use of isoniazid, rifampin, ethambutol, and pyrazinamide.…”

“…If symptoms fail to resolve with antibiotics, it may indicate a misdiagnosis of CD or drug-resistant TB [ 17 ]. Therefore, endoscopic reassessment for any mucosal healing may aid in the diagnosis [ 19 ].…”