The case of a strange type of generalized xanthogranulomatosis, ending by a lethal kidney complication, is described in a woman aged 68. The clinical symptoms of the patient were not characteristic and did not lead to the actual diagnosis. The process was located along the basal brain arteries, it adhered to the adventitia of the descending thoracic aorta and of the coronary arteries. An identical xanthogranulomatous infiltrate was found in the peripelvic adipose tissue of both kidneys, where it led to stenosis of the proximal ends of both ureters; to a lesser extent such infiltrates appeared also in the periportal areas of the liver and in the bone marrow. Histological findings grant the possibility of the Erdheim-Chester disease. Differential diagnosis is subjected to discussion.