Progressive multifocal leukoencephalopathy in an HIV-infected child.

Progressive multifocal leukoencephalopathy is an infection of the immunosuppressed, especially of AIDS, patients. The disease is caused by the JC virus and is exceptionally rare in children. The diagnosis is based on MRI and on the detection of JC virus DNA in the cerebrospinal fluid. Progression is relentless in most cases. The only treatment of proven benefit is restoration of the immune system by highly active antiretroviral therapy. We report the case of a 15S-year-old HIV-infected boy. After several months of fatigue he developed apathy, head tilt, diplopia, motor apraxia and unsteady gait. Physical examination revealed mild cerebellar signs. MRI showed a 30-mm large, non-enhancing, hyper-intense area in the right cerebellar hemisphere and the middle cerebellar peduncle. JC virus DNA was detected in the cerebrospinal fluid. Two weeks later the MRI showed progression. The patient's condition rapidly worsened and he died four months after the onset of the disease. Autopsy revealed widespread lesions of the cerebellar hemispheres and the brainstem. The case presented is peculiar owing to the young age of the patient, the unusual localization and the unifocal nature of the lesion.