It was caused by a gram-positive actinomycete, the bacterium Tropheryma whippelii . Although many organs can be affected, the small intestine is the primary site involved. The HLA-B27 gene is more common in Whipple's disease patients. Classically, the disease begins in a middle-aged male with a nondeforming arthritis that usually starts years before the onset of the intestinal symptoms. The arthritis of Whipple's disease mimics that of rheumatic fever in some respects.
Recurrences are common, and the disease can be migratory.
Less often, small joints of the hands and feet are inflamed, and the arthritis becomes chronic and resembles rheumatoid arthritis. The cardiac involvement of Whipple's disease includes the endocardium, myocardium, pericardium, and even the coronary arteries, it is not surprising that these patients occasionally have congestive heart failure and symptomatic pericarditis . Valvular lesions, especially of the mitral and aortic valves, may be sufficiently severe to cause hemodynamically significant stenosis or insufficiency. However, many patients with involvement of the heart have no cardiac symptoms. A broad range of CNS symptoms of Whipple's disease has been reported because virtually all portions of the brain or spinal cord may be involved.