Unusual MRI and pathologic findings of progressive multifocal leukoencephalopathy complicating adult Wiskott-Aldrich syndrome.

We present a long-surviving patient with Wiskott-Aldrich syndrome complicated by atypical progressive multifocal leukoencephalopathy (PML). MRI showed multiple tiny spots of Gd-DTPA-enhanced lesions on the T1-weighted image. Pathologic findings for brain biopsy were patchy demyelinated vascularized lesions infiltrated by a surprising number of eosinophils. The presence of polyomavirus JC was confirmed by in situ hybridization and polymerase chain reaction. PML should be included in the differential diagnosis when Gd-DTPA-enhanced spotty lesions are present in the white matter, especially in patients who have a mild immunologic defect.