In a case of pediatric Whipple disease confined to the central nervous system, white matter lesions initially appeared as areas of very low signal intensity on T1-weighted MR images and as areas of hyperintensity on proton density-weighted and T2-weighted images, and showed slight peripheral enhancement on delayed contrast-enhanced T1-weighted images. On MR studies obtained 3 and 6 months after antibiotic therapy, the lesions had decreased in size and no longer enhanced. They became progressively less hypointense on T1-weighted images and less hyperintense on T2-weighted images.