S2936 Primary Gastric Tuberculosis in a Patient With New Human Immunodeficiency Virus

INTRODUCTION: Mycobacterium tuberculosis is a common and challenging-to-treat infectious organism affecting more than 1.7 billion people globally. While primarily a respiratory illness, it can spread to other parts of the body, including the gastrointestinal tract. Abdominal tuberculosis (TB) is rare, accounting for 5% of all TB cases worldwide, of which only 1–2% involve the stomach. Most gastric cases are secondary to pulmonary infections, however primary gastric TB can arise following ingestion of the organism. We describe a case of primary gastric TB in a patient with newly diagnosed human immunodeficiency virus (HIV). CASE DESCRIPTION/METHODS: A 40-year-old man visiting from Ecuador with no prior medical history presented to the emergency room with one month of abdominal bloating and decreased oral intake. Physical examination was notable for cachexia and oral thrush; however, the abdomen was soft, nontender and nondistended. Blood work was positive for HIV with a CD4 count of 34 cells/mm3. An abdominal CT revealed an ill-defined soft tissue mass along the lesser curvature of the stomach with numerous enlarged adjacent lymph nodes. Subsequent upper endoscopy showed a friable gastric mass within the cardia and an erosion in the lesser body. Biopsies were obtained and pathology was notable for numerous acid-fast bacilli. Neither H. pylori nor carcinoma was identified. PCR analysis of tissue was positive for M. tuberculosis. Evaluation for pulmonary TB was unremarkable with a normal chest x-ray and negative sputum acid fast stains. The patient was ultimately discharged on anti-TB therapy with a plan to initiate antiretroviral therapy the following week. DISCUSSION: Primary gastric TB is exceedingly rare and is generally observed in patients with immunosuppression secondary to HIV, cirrhosis, diabetes, or treatment with anti-tumor necrosis factor agents. Abdominal TB primarily arises via reactivation of a latent infection, however primary cases may arise from ingestion of unpasteurized milk or undercooked meat. The rarity of gastric TB has been attributed to the low density of lymphoid tissue, acidic pH, and rapid emptying of stomach contents. Typical sites of involvement include the antrum and pre-pyloric area with lesions typically being ulcerative. Treatment is similar as to pulmonary TB with prolonged antibiotic therapy, however symptoms of perforation, abscess bleeding, or obstruction may require surgery.Figure 1.: A 4.9 cm × 4.3 cm ill-defined soft tissue mass along the lesser curvature of the stomach with numerous enlarged gastrohepatic ligament and retroperitoneal lymph nodes.Figure 2.: Friable gastric mass within the cardia.