A 45–year–old female with type 2 diabetes was admitted to the orthopedic surgery service with a painful right thigh mass and hyperglycemia. Her pain had progressed over the past month and was now severe enough to prohibit weight bearing. MRI showed a large, necrotic mass in the anterior compartment of the right thigh involving the majority of the femoral length; a moderate–sized right knee effusion was also seen. Sarcoma was initially suspected, and a tissue diagnosis was sought. The hospitalist service was consulted to assist with glycemic management and operative risk assessment. Blood glucose control proved challenging despite daily increases in both long– and short–acting insulin. A core needle biopsy of the right thigh mass revealed purulent fluid, and Gram–positive cocci were identified on Gram stain. Histology was remarkable only for fibrosis. Vancomycin was started and the patient underwent both incision and drainage of the right thigh mass and arthrocentesis of the right knee. Cultures from the right thigh grew methicillin–sensitive Staph aureus and antimicrobial coverage was changed to oxacillin. Four days after the arthrocentesis, the lab discovered yeast on the Gram stain of the right knee aspirate; amphotericin B was added for broad fungal coverage, and a right knee arthrotomy was performed. On hospital day 11, the pathology report from the right thigh incision and drainage returned with a surprising result. Histology was consistent with epithelioid hemangioendothelioma (EHE), an extremely rare vascular tumor. Two days later, culture of the right knee aspirate turned positive for Cryptococcus neoformans. There was no evidence of fungal disease elsewhere, and serum cryptococcal antigen was negative. In addition, imaging did not show evidence of tumor involvement beyond the right leg. Glucose control improved markedly with antibacterial and antifungal therapy. The patient was discharged home to complete four weeks of oxacillin and ten weeks of oral fluconazole. A future appointment was arranged with orthopedic oncology for management of EHE.
EHE is a rare, low–grade, malignant vascular tumor of soft tissue and bone, although it may also occur in other sites such as the lung and liver. It most commonly presents as a solitary mass and does not have a preference for gender or age. EHE is considered to be insensitive to chemotherapy; complete local excision is the treatment of choice. Radiation therapy is sometimes utilized. Cryptococcal septic arthritis is also rare, especially in the absence of systemic dissemination. This patient was at higher risk due to uncontrolled diabetes and a concomitant malignancy.
Our aim in reporting this case is to increase awareness of two rare causes of lower extremity pain as well as to highlight the value of collaborating with consultants in an inpatient setting.