Microsporum canis pseudomycetoma and disseminated Mycobacterium genavense infection in an HIV/AIDS patient, an unusual combination

Abstract

Pseudomycetomas are rare fungal subcutaneous infections caused by dermatophytes, which are mainly observed in immunocompromised patients. Mycobacterium genavense is considered an opportunistic pathogen in people living with HIV/AIDS (PLWHA), clinically resembling the presentation of Mycobacterium avium complex (MAC). Here, we describe the case of a 26-year-old PLWHA with a 3-month history of a 4 cm tumoral, duroelastic and painful lesion located on the back. Histopathology of the tumoral lesion revealed chronic granulomatous inflammation with grains composed of PAS-positive and Grocott-positive septate hyphae, as well as acid-fast bacilli (AFB). Culture on Sabouraud and lactrimel agar developed colonies that were later identified as Microsporum canis. In successive samples, the AFB were identified as M. genavense by restriction analysis of PCR products. Immunocompromised PLWHA not only suffer increased susceptibility to diseases due to unusual pathogens but also atypical clinical presentation of frequently encountered pathogens.