Necrobiotic xanthogranuloma without monoclonal gammopathy and with a rapidly fatal outcome

Necrobiotic xanthogranuloma is an extremely rare form of histiocytosis that presents clinically as yellowish infiltrated plaques or nodules. Ocular involvement is seen in over 80% of cases. Histopathology reveals numerous xanthomous histiocytes and collagen necrobiosis. Benign monoclonal gammopathy associated with myeloma is found in 80% of patients, but the course is normally long, with 100% survival at 10 years. A 76-year-old man presented skin lesions that subsequently became ulcerated. The clinical appearance and histopathological examination resulted in diagnosis of necrobiotic xanthogranuloma. No monoclonal gammopathy or myeloma was seen. The disease was marked by sensitivity to corticosteroids with failure of other therapies (cyclophosphamide, alpha interferon), onset ofcorticosteroid dependency, iatrogenic Cushing's syndrome and diabetes, which were in part responsible for the infectious complications and subsequent death of the patient. Necrobiotic xanthogranuloma is difficult to treat, even in the absence of myeloma or monoclonal gammopathy. Corticosteroids are probably the most efficacious treatment, but can give rise to multiple complications, resulting in this particular case in death of the patient.