The patient is a 50 year old-man with a PMH of HIV for 16 years who presented to his PMD with diarrhea. He noted crampy abdominal pain, frequent loose bowel movements occasionally associated with bleeding, a ten pound weight loss and perianal pain. Stool cultures collected at that time were negative. His symptoms did not improve over the next few months and he presented to the emergency room with 10 to 15 loose BM's per day and perianal pain. He was found to have a perianal fistula with abscess formation. The abcess was drained and he was treated with antibiotics. Follow-up colonoscopy revealed normal appearing mucosa, but random biopsies taken throughout the colon revealed pancolitis with granuloma formation. Pathology reports were negative for acid fast bacilli, fungal or viral elements and the patient was diagnosed with Crohn's disease. He was started on Asacol and had a dramatic clinical improvement. His stool frequency decreased to 3–4 bowel movements per day with no bloody discharge. This patient was originally diagnosed with HIV in 1988. His disease has been well controlled, with his CD4 count ranging from 450 to over 1000. His anti-retroviral therapy had been discontinued in 2003 because of episodes of lactic acidosis; while on therapy he had an undetectable viral load. His CD4 count at the time of this presentation was 926. He had problems with constipation and diarrhea intermittently over the last 15 years and had been previously diagnosed with irritable bowel syndrome. Before this presentation he had never had a colonoscopy. The differential diagnosis for diarrhea in an HIV patient includes a wide variety of bacterial, viral and protazoal pathogens. Crohn's Disease (CD) is not commonly thought of as a potential cause of diarrhea in an HIV patient, although HIV and Crohn's can certainly co-exist. Case reports by James in 1988 and Yoshida in 1996 showed resolution of CD symptoms in patients who contracted HIV. Reports by Bernstein in 1994 and Lautenbach in 1997 showed that patients with HIV can have active CD even in the setting of markedly decreased CD4 counts. This is the first reported case of newly diagnosed CD in a patient with long-standing HIV. With great advances in the treatment for HIV, patients are maintaining normal immunity, and living, for longer periods of time. As a result, IBD may become more commonly seen in patients with HIV.