Mixed Pneumocystis and Cryptococcus cutaneous infection histologically mimicking xanthoma.

Cutaneous Pneumocystis jirovecii infection is rare. It is thought that the disease emerges from a latent infection delivered via hematogenous and/or lymphatic dissemination from a primary lung infection in immunocompromised individuals. A 32-year-old human immunodeficiency virus–positive male was admitted for headache and vomiting. He was diagnosed with meningitis due to Cryptococcus neoformans and sputum tested positive for Pneumocystis. Six months later, he presented with a slightly crusted yellowish brown plaque and 2 similar but smaller papules with telangiectasia near the right angle of the mouth. Biopsy of the area featured histiocytes expanded by foamy cytoplasm as in a xanthoma except that the vacuoles were coarser. Special stains ultimately demonstrated the characteristic disks of Pneumocystis accompanied by a minor component of budding yeasts (Cryptococcus) in the same fields. This case illustrates the utility of adequate special stains in recognizing a mixed cutaneous infection, particularly in human immunodeficiency virus–positive patients, when microscopy presents an odd xanthoma-like lesion.