Small Bowel Kaposiʼs Sarcoma: An Unusual Cause of GI Bleeding

Abstract

Purpose: A 34-year-old previously healthy man presented with 1 week of melena and new right sided hemiplegia for 1 month. Initial hemoglobin was 6 g/dL from a baseline of 13.5 g/dL two years prior. Brain MRI showed two ring enhancing lesions in the left cortex and cerebellum suspicious for toxoplasmosis. An HIV antibody test was positive, with a CD4 count of 1. An upper endoscopy was performed and showed white adherent material in the esophagus (biopsy pathology positive for candidiasis), gastric erythema and normal duodenum without a bleeding source. Colonoscopy showed normal terminal ileal and colonic mucosa. A capsule endoscopy demonstrated a raised medium-sized submucosal erythematous mass in the mid-jejunum, suspicious for Kaposi's sarcoma (KS). A detailed skin exam yielded a violaceous plaque on the abdomen, with biopsy pathology diagnostic of KS. The patient was started on antiretroviral therapy (ART) and treatment for cerebral toxoplasmosis, with no further episodes of melena. KS is a vascular tumor that is associated with human herpesvirus 8 and is the most common tumor arising in HIV-infected persons. Its prevalence is increased with lower CD4 counts. KS was over 20,000 times more common in persons with AIDS than in the general population prior to the widespread use of highly active antiretroviral therapy (HAART), and the incidence has declined substantially since that time. Although KS can involve virtually any site in the body, cutaneous disease is most common and is the usual initial presentation for KS. The most frequent sites of noncutaneous disease are the oral cavity, gastrointestinal tract (most commonly the small intestine) and respiratory system. Prior to widespread ART, the gastrointestinal tract was involved in approximately 40% of patients with KS at initial diagnosis, and in up to 80% at autopsy. However, visceral involvement as the initial manifestation of KS in the HAART era is relatively uncommon. GI lesions may be asymptomatic or cause weight loss, abdominal pain, nausea and vomiting, upper or lower gastrointestinal bleeding, malabsorption, intestinal obstruction or diarrhea. On endoscopy, KS lesions are easily recognized as hemorrhagic nodules that can appear anywhere along the GI tract. In the HAART era the incidence of AIDS-related KS has dramatically decreased to less than 10% of the incidence reported in the pre-HAART era, but it is still recognized as a primary AIDS-defining illness that can lead to significant morbidity. Rarely, visceral KS can present as occult or gross GI bleeding. In persons with underlying AIDS presenting with anemia and/or GI bleeding, it is important for physicians to consider intestinal KS as a possible etiology.