Panniculitis in a Woman With Opportunistic Pulmonary Coinfection by Pneumocystis jirovecii and Cryptococcus neoformans: 18F-FDG PET/CT Revealing the Infection and Assessing Treatment Response.

A 56-year-old woman, with history of psoriasis well controlled on ustekinumab, underwent 18F-FDG PET/CT to explore first onset of histologically proven skin panniculitis of unknown origin. PET/CT showed high uptake in panniculitis lesions in limbs and in a lung opacity suggestive of pneumonia. Based on PET/CT findings, a bronchoalveolar lavage revealed pulmonary coinfection by Pneumocystis jirovecii and Cryptococcus neoformans. Thus, hematogenous dissemination of infection was suspected as etiology of panniculitis. She was treated with fluconazole and trimethoprim-sulfamethoxazole, leading to total resolution of skin lesions. Posttherapeutic PET/CT showed complete metabolic response of skin and pulmonary lesions.