Sporotrichosis is a subcutaneous fungal infection of zoonotic or environmental transmission that typically presents as localized disease in immunocompetent individuals but may become disseminated and severe in cases of advanced immunosuppression. We report a 39-year-old cisgender man with newly diagnosed AIDS (CD4 40 cells/mm³, 40-kg weight loss in 4 months), who presented with ulcerated, crusted, and painful vegetative skin lesions affecting the trunk, limbs, face, and oral mucosa. No contact with cats or high-risk exposures was reported. Mpox was ruled out by PCR. Empirical tuberculosis treatment was initiated based on a positive urinary LF-LAM test (without microbiologic confirmation), along with antiretroviral therapy. Four weeks later, lesions worsened significantly, compatible with immune reconstitution inflammatory syndrome (IRIS), prompting hospitalization. Tests for histoplasmosis (urinary antigen), cryptococcosis (serum antigen), and leishmaniasis (lesion PCR) were negative. Chest CT was unremarkable. Skin biopsies revealed round fungal structures initially suggestive of histoplasmosis. Liposomal amphotericin B was started but quickly discontinued due to lesion progression. Itraconazole 400 mg/day was added, leading to marked improvement within 14 days, with amphotericin discontinuation. Fungal culture identified Sporothrix sp. , confirmed as Sporothrix brasiliensis by MALDI-TOF and genetic sequencing. This case illustrates the diagnostic challenges of disseminated sporotrichosis in advanced HIV, particularly during IRIS, and reinforces the limited efficacy of amphotericin B against S. brasiliensis, a species associated with greater virulence and reduced susceptibility to polyenes. The favorable clinical response to high-dose itraconazole underscores its role as cornerstone therapy, even in severe disease. Accurate microbiological diagnosis and recognition of IRIS as an aggravating factor are critical for management in endemic regions.
Honesko et al. (Sun,) studied this question.