Invasive Cryptococcus laurentii disease in a nine-year-old boy with X-linked hyper-immunoglobulin M syndrome.

We report a 9-year-old boy with X-linked hyper-immunoglobulin M syndrome and invasive Cryptococcus laurentii infection identified on the basis of morphologic and biochemical characteristics and serologic tests. Fluconazole treatment resulted in complete recovery. We believe that C. laurentii should be included in the differential diagnosis of opportunistic fungal infections in patients with primary T cell immunodeficiencies.