CD4 and thymoma: 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.<h4>Case report</h4>A 63-year-old male presented with a chronic skin lesion confirmed as <i>Cryptococcus neoformans</i> on biopsy and an incidental mediastinal mass found during infectious work-up for the notable cluster of differentiation 4 (CD4)+ lymphopenia.