A “Case” of Granuloma

Abstract

Purpose: Case Presentation: A 22 year old Vietnamese immigrant in Canada for 16 years presented with a 5 month history of abdominal pain, weight loss and diarrhea. History was negative for medical problems, medication and drug use, smoking, alcohol, gastrointestinal bleeding, constitutional symptoms, infectious contacts, recent travel and extraintestinal manifestations of inflammatory bowel disease (IBD). Family history was negative for tuberculosis, IBD and colon cancer. Physical exam showed a pale, cachectic, afebrile, hypotensive (88/54) man with no postural drop. There was mild left lower quadrant tenderness and no lymphadenopathy. Lab investigations revealed hemoglobin 117 g/L, white blood cell count 20.6 × 109/L, neutrophil count 16.9 × 10∧9/L, mean corpuscular volume 79.1 fL and serum albumin 29 g/L. Remaining blood tests including electrolytes, creatinine, liver enzymes, amylase and TSH were within normal limits. Serum endomysial antibody and stool testing were negative. Colonoscopy showed a fistulous opening at the base of the cecum, marked mucosal nodularity with multiple pseudopolyps, deep ulcers and areas of denudation in the cecum, ascending and mid-transverse colon. Corticosteroid therapy was deferred due to possibility of tuberculosis. Intestinal biopsies showed moderate acid-fast bacillus with necrotizing granulomas. Nucleic acid amplification test was positive for Mycobacterium tuberculosis complex. The patient's gastrointestinal symptoms improved with antituberculous treatment and he made a full recovery. Discussion: Our case illustrates three important principles in the diagnosis and treatment of gastrointestinal tuberculosis (GI TB). First, tuberculosis infection should be considered in patients with clinical, endoscopic, radiological and histopathological features of Crohn's disease, especially where there is a predominance of ileal and cecal involvement. Immigration from a country with known endemic tuberculosis is an important risk factor, even if immigration is a remote event. Nonspecific symptoms of GI TB include fever, night sweats, weight loss, abdominal pain and diarrhea. Diagnosis of GI TB is based on detection of acid-fast bacilli in tissue or stool. Second, it is important to exclude the possibility of tuberculosis before the commencement of corticosteroid therapy, often used in the treatment of IBD, since corticosteroid therapy will increase morbidity of the patient with GI TB. Third, treatment of GI TB is primarily medical and although complications such as fistula formation, perforation and hemorrhage may require surgery, it is possible to treat gastrointestinal fistulae due to tuberculosis successfully with medical therapy alone.