Kaposi Sarcoma in an HIV-Negative Octogenarian with Steroid Refractory Colitis

Abstract

Purpose: An 80-year-old HIV-negative Libyan female who presented to us in 2005 with iron deficiency anemia underwent colonoscopy, which revealed multiple small-mouthed diverticula in the sigmoid and descending colon and a small sessile polyp (which was biopsied). Pathology revealed benign mucosa with hyperplastic change and lymphoid aggregates - the patient was then managed conservatively. In 2009, she developed hematochezia with a hemoglobin of 8.7 and required blood transfusions. A colonoscopy at that time showed a diffuse area of congestion, erythema, and inflammation in the recto-sigmoid colon which was biopsied. The pathology revealed ulcerations, active inflammatory changes with cryptitis, crypt abscesses and epithelioid granulomas consistent with inflammatory bowel disease. During the following year, she was treated with mercaptourine, infliximab and steroids without clinical remission. She was ultimately referred to a colorectal surgeon for management of steroid-refractory ulcerative colitis. In December 2010, she underwent a proctocolectomy with end-ileostomy. The surgical specimen was submitted for pathologic evaluation. The histologic exam showed a submucosal spindle cell proliferation with formation of capillary, slit-like channels demonstrating high-grade nuclear atypia and high mitotic count. The lesion stained positive for CD34 and CD31 markers, consistent with vascular neoplasm. The patient was evaluated by Hematology/Oncology and was found to have developed multiple 0.5-1.0 cm purplish nodules bilaterally on the anterior lower extremities. Punch biopsies were taken and revealed similar morphologic findings to those seen in the colon. Given her Mediterranean background, further immunohistochemical staining for Kaposi Sarcoma was performed on both the colon and skin biopsies; these both stained positive for HHV-8, compatible with Kaposi Sarcoma. CT scan at that time showed multiple lung nodules as well as splenic lesions consistent with a metastatic pattern of spread. She was started on systemic chemotherapy with liposomal doxorubicin and responded well with resolution of her pulmonary and splenic lesions. Her anemia also resolved, and she had no further GI bleeding. There have been several reported cases of colonic Kaposi Sarcoma in HIV-negative patients with ulcerative colitis, although none in a patient as old as ours. This case demonstrates the importance of a high degree of clinical suspicion to diagnose potential HHV-8 associated Kaposi Sarcoma as an opportunistic infection in immunocompromised colitis patients, even those who are octogenarians.