[Interstitial pneumonitis associated with Sweet's syndrome in the elderly]

Sweet's syndrome occurring during the course of interstitial pneumonitis in a 70-year-old woman was encountered. She was admitted because of dyspnea on exercise, dry cough and interstitial shadow on chest x-ray. Lung biopsy, together with other findings confirmed interstitial pneumonitis. Five days after admission, genital ulcer and aphtha on the oral mucosa were detected and exudative erythema appeared on her right shoulder, chest and back. Histological examination of the skin lesions demonstrated numerous nutrophilic infiltration in the upper dermis, indicating Sweet's syndrome. The skin eruption rapidly disappeared on treatment with colchicine. Although six months after admission interstitial pneumonitis caused respiratory failure, treatment with prednisolone and cyclophosphamide was effective. Serological and immunological tests demonstrated hyper-gammaglobulinemia and positive reaction for anti SS-A antibody. Pathological examination of the lip revealed numerous lymphocyte infiltrates around the duct of the minor salivary gland, suggesting Sjögren's syndrome as the background disease of Sweet's syndrome and interstitial pneumonitis. This evidence indicating that even in elderly patients, skin lesions of Sweet's syndrome may reveal the background disease.