Relapsing Whipple's disease presenting with hypopituitarism.

A 44-year-old man with a history of Whipple's disease 8 years ago presented with recurrent grand mal seizures and signs of hypopituitarism on physical examination. Magnetic resonance imaging of the brain revealed a hypothalamic lesion of 1 cm diameter in the region of the rostral infundibulum. Hypopituitarism was confirmed by low levels of serum cortisol, free testosterone and free thyroxine without an elevated TSH. Whipple encephalitis with hypothalamic involvement was suggested and verified by positive polymerase chain reaction (PCR) for Tropheryma whippelii in the cerebrospinal fluid. PCR for T. whippelii has become an important diagnostic tool for establishing the diagnosis of Whipple's disease especially in patients with unusual presentations and if the diagnosis cannot be confirmed histologically. Whipple's disease should be included in the differential diagnosis in hypopituitarism caused by infectious disease.