Pancarditis in Whipple's disease: electronmicroscopic demonstration of intracardiac bacillary bodies.

The advent of electron microscopy has repeatedly confirmed Whipple's original postulate that bacterial infestation might be the cause of intestinal lipodystrophy (Whipple's disease). We have recently studied two patients, a 67-year-old man and a 38-year-old woman, who died of untreated Whipple's disease, and both were found to have clinically unrecognized pancarditis. Histologically, PAS-positive histiocytes in foci of chronic inflammation were demonstrable in several organs, including the heart. Electron microscopy of autopsy tissues showed numerous intracellular and extracellular rod-shaped bacillary bodies and serpiginous membranes. The bacillary bodies, some sectioned transversely and others longitudinally, were about 0.2 mum wide and 2 mum long; each had a double-layered cell wall. These bacillary bodies have not been previously identified in the heart, and may be casually related to cardiac lesions occurring in many untreated cases of Whipple's disease.