WHIPPLE's DISEASE
Whipple's disease is a rare multisystem disease with only 664 known cases before 1985 and less than 30 new cases being reported per year worldwide. Prior to antibiotic therapy the disease was uniformly fatal. Symptoms typically precede diagnosis by 5 to 10 years. Because of the many clinical findings shared by other common disorders, considering a diagnosis of Whipple's disease is one of the most important steps regarding therapy. Beginning insidiously with complaints of arthralgia, myalgia, fever, and weight loss and progressing to diarrhea, it is usually diagnosed during the work-up of the malabsorption, which is the hallmark of Whipple's disease. Joint pain and swelling are common, followed by steatorrhea with protein, carbohydrate, vitamin, and mineral malabsorption. Microcytic, iron-deficiency anemia is common, as is macrocytic anemia, from B-12 and folate deficiency. Cardiac involvement includes endocarditis of any valve, myocarditis, and pericarditis. The eye is sometimes involved, with uveitis, choreoretinitis, or keratosis. The most feared manifestation, central nervous system (CNS) Whipple's disease, is associated with headache, personality change, ataxia, ophthalmoplegia, seizures, and dementia.
The etiologic agent, Tropherma whipplei, is a gram-positive, periodic acid–Schifff (PAS)- positive, non-acid-fast, rod-shaped bacillus with typical electron microscopy morphology. The organism is grown only in cell culture, using peripheral blood monocytes. Host interaction is likely involved in the pathogenesis of Whipple's disease. In autopsy series, the frequency is less than 0.1%; 40- to 50-year old men predominate, and 97% are white.