S6288 Don’t Be Rash, Go With Your Gut: A Case of Exclusive GI Involvement of Kaposi Sarcoma in a Patient With Advanced HIV

Introduction: Kaposi sarcoma (KS) is a vascular tumor associated with human herpesvirus 8 (HHV-8), which is associated with HIV. KS is most often found on the skin. In fact, only about 3.4-10% of cases present without cutaneous lesions. When there is gastrointestinal (GI) involvement (GI-KS), patients may present with nausea, vomiting, abdominal pain, and/or GI bleed. Others may be asymptomatic. Here we describe the case of a patient with HIV who had asymptomatic GI-KS without any cutaneous lesions. Case Description/Methods: A 30-year-old man with history of pancolitis status-post antibiotic treatment presented with oral thrush, abdominal pain, and bloody diarrhea. He was diagnosed with HIV. Stool studies were positive for shigella and cryptosporidium. Esophagogastroduodenoscopy (EGD) and flexible sigmoidoscopy were performed. EGD showed a single 15 mm protruding, sessile mucosal nodule in the gastric incisura. Pathology showed proliferation of spindle cells, staining positive for HHV-8, CD31, CD34, and ETS-related gene, all findings consistent with KS. Flexible sigmoidoscopy found diffuse friable, erythematous, ulcerated, and nodular mucosa that ultimately showed cytomegalovirus colitis. Staging computed tomography showed a 1.6 mm gastric nodule, though it was unclear if this was an artifact. No metastatic disease was found. The patient is undergoing treatment for the above infections and is on highly active antiretroviral therapy. Discussion: Although GI-KS is not uncommon, there are only a few reported cases of exclusive GI involvement, such as in this patient. This case is also rare since this patient had no symptoms from the GI-KS, possibly since the lesion had not yet progressed. Therefore, this case gives us a valuable picture of how earlier-stage GI-KS appears endoscopically and histologically. It also suggests that screening endoscopies should perhaps be part of the standard of care for patients diagnosed with advanced HIV in order to diagnose GI-KS before further progression.