Whipple disease of the nervous system.

A 58-year-old man with dizziness and unsteady gait had a 10-year history of behavioral change, impotence, and a progressive peripheral neuropathy. CT revealed low-density, contrast-enhancing lesions in the right pontine tegmentum and the right medial temporal lobe. Temporal lobe biopsy contained a collection of mature histiocytes, with PAS-positive rod-shaped inclusions. These inclusions, when studied by electronmicroscopy, were seen to be membrane-bound bacilliform bodies. Peroral jejunal biopsy contained no such inclusions. Despite treatment with antibiotics, the patient's neurologic illness progressed, and he succumbed to intercurrent sepsis. We believe this to be the first instance in which a lesion of Whipple disease has been identified within the CNS by CT scan, and the diagnosis made antemortem, in the absence of demonstrable systemic disease.