Whipple's disease is a chronic inflammatory systemic disorder in which all organs can be invaded by the rod-shaped bacterium Tropheryma whipplei. It is a rare disease and frequently misdiagnosed, though there is no valid estimate of its actual incidence and prevalence. Only about 1,000-1,500 cases have been reported. The clinical course of untreated Whipple's disease can include three stages: (1) a non-specific prodromal stage which includes migratory polyarthralgias; (2) a classic abdominal manifestation which involves weight loss, weakness, chronic diarrhea, and abdominal pain; and (3) a generalized stage characterized by steatorhea, cachexia, lymphadenopathy, hyper-pigmentation, and cardiovascular, pulmonary, and neurological dysfunction. The authors describe a case of a 39-year-old male patient with about a year's history of generalized adenopathy, inappetence, weight loss, progressive weakness, subfebrilities, and convulsive abdominal pain. Following primary exclusion of a tumor disease, a lymph node biopsy demonstrated a typical picture of a granulomatous inflammation-Whipple's lymphadenitis with partial exemption of the Gram reaction, and stain features corresponding to T. whipplei, which is regarded as the etiological agent causing this disorder. Further tests confirmed the generalized form of the disorder, affecting the lymphatic tissues, gastrointestinal system, respiratory system, and nervous system, with sensory and motor polyneuropathy. HLA-B27 antigen, which is frequent among those with Whipple's disease, was also present. Following treatment for three months with antibiotics a significant reduction of the changes typical of Whipple's disease was found upon follow-up biopsy, hence we assume the applied therapy was successful. In our case study we emphasize the atypical course of the disease with dominant generalized lymphadenopathy and only mild gastrointestinal symptoms.