Synopsis of endoscopic and related morphological findings in Whipple's disease.

Whipple's disease is characterized by typical endoscopic lesions in the duodenal wall. They consist of a thickened and inflamed mucosa with yellowish-white spots, in part solitary, in part confluent. Petechial hemorrhages mark the high mucosal vulnerability. Clumsy and dilated villi with ectatic lymph vessels and PAS-positive macrophages are the corresponding histologic feature. In the ultrastructure numerous rod-shaped micro-organisms are evident. Following treatment with tetracycline the mucosal surface normalizes rapidly, the bacteria disappear, whereas other histologic changes remain over a longer period of time.