[Acute febrile neutrophilic dermatosis (Sweet syndrome). Case report and immunohistologic study of neutrophil-associated proteolytic enzymes and their inhibitors].

A 59-year-old female patient who developed fever, headache, arthralgia and painful, raised red cutaneous plaques located predominantly on the upper trunk is presented. On the basis of the clinical and histological findings acute febrile neutrophilic dermatosis (Sweet's syndrome) was diagnosed. In affected skin we applied immunohistochemical methods to examine the topographical organization of neutrophil-associated proteinase/proteinase inhibitor systems, i.e. the PMN-elastase/alpha 1-proteinase inhibitor and the cathepsin G/alpha 1-antichymotrypsin systems. Cathepsin G, PMN-elastase and alpha 1-antichymotrypsin were found in association with the polymorphonuclear infiltrating cells, whereas alpha 1-proteinase inhibitor was localized exclusively in the subepidermal oedema. In conclusion, our immunohistological findings support the view that free PMN-elastase is involved in the pathogenesis of cutaneous lesions in Sweet's syndrome.