cutaneous cryptococcal infection: initial manifestation of acquired t-cell immunodeficiency due to malignant thymoma

Background and purpose: cryptococcosis is a known opportunistic infection. thymomas are known to cause immune dysregulation. we describe an atypical case of cutaneous cryptococcosis in a patient with acquired t cell immunodeficiency that has been found to be secondary to a type b3 thymoma with progression to carcinoma. case report: a 63-year-old male presented with a chronic skin lesion confirmed as cryptococcus neoformans on biopsy and an incidental mediastinal mass found during infectious work-up for the notable cluster of differentiation 4 (cd4)+ lymphopenia. this led to the diagnosis of a type b3 thymoma requiring resection. the cryptococcal lesion was treated successfully with azole therapy. conclusion: c. neoformans is an opportunistic infection rarely associated with isolated t cell immunodeficiency due to thymomas. a multidisciplinary approach and understanding of the pathogenicity of cryptococcus and the immunological effect of thymic dysfunction are paramount to diagnosis and treatment.