S4049 Severe Immunosuppression Revealing High-Grade B-Cell Lymphoma in a Patient With Untreated HIV

Introduction: HIV infection, if untreated, can lead to significant immunosuppression, ultimately predisposing patients to opportunistic infections and AIDS-defining malignancies such as high-grade B-cell lymphoma. Nonspecific symptoms may be the initial presentation of a serious underlying process. We present a case of newly diagnosed AIDS with gastrointestinal lymphoma, which was initially suspected to be inflammatory bowel disease, as well as opportunistic esophageal candidiasis. Case Description/Methods: A 31-year-old man with a history of untreated HIV presented with abdominal pain, unintentional weight loss and occasional night sweats. Initial labs revealed hemoglobin 5.6 g/dL, mean corpuscular volume 84.9 fL, and he received 2 units of packed red blood cells. Stool pathogen panel was negative, and fecal calprotectin was not elevated. Erythrocyte sedimentation rate and C-reactive protein were 27 mm/hr and 74 mg/L, respectively. HIV screen showed a positive antibody with a negative p24 antigen. CD4 count was 12 cells/μL, and HIV viral load was 155,000 copies/mL. Computed tomography abdomen/pelvis showed marked wall thickening of the ascending, hepatic flexure and transverse colon with pericolonic fat stranding. Magnetic resonance imaging abdomen showed diffuse colitis. Colonoscopy revealed circumferential ulceration and mass-like lesions in the transverse and descending colon, raising concern for colocolonic fistulizing Crohn disease. Biopsies demonstrated high-grade B-cell lymphoma. Esophagogastroduodenoscopy showed patchy white plaques throughout the esophagus with biopsy confirming esophageal candidiasis. The patient was empirically started on intravenous (IV) ceftriaxone, metronidazole and fluconazole. HAART was initiated along with trimethoprim-sulfamethoxazole for primary prophylaxis of pneumocystis pneumonia. Due to his immunocompromised state, he was deemed a poor surgical candidate. Oncology was consulted and initiated treatment with R-CHOP. He was discharged with close follow-up plans for chemotherapy and HIV management. Discussion: This case demonstrates the importance of keeping a broad differential when evaluating gastrointestinal symptoms in patients with newly diagnosed or untreated HIV, as severe immunosuppression can mimic or mask other diseases. In this case, findings that were initially concerning for inflammatory bowel disease were actually indicative of underlying malignancy. Prompt recognition, early treatment, and multidisciplinary care are critical in preventing and managing AIDS-related complications, as well as improving patient outcomes.