Skin and Soft Tissue Mucormycosis in Patients Receiving Bruton Tyrosine Kinase Inhibitors: Case Report and Literature Review.

Bruton tyrosine kinase inhibitors (BTKis) have been associated with an increased risk of invasive fungal disease, with skin and soft tissue mucormycosis accounting for a minority of cases. We present a 72-year-old patient with chronic lymphocytic leukemia who developed necrotizing fasciitis and myositis due to Lichtheimia spp after 4 months of therapy with the second-generation BTKi zanubrutinib, with a fatal outcome despite aggressive treatment. Our literature review identified 7 additional cases of BTKi-associated skin and soft tissue mucormycosis, revealing an all-cause mortality rate of 37.5%. Two-thirds of the patients had a previous trauma or skin lesion.