Acute febrile neutrophilic dermatosis (Sweet's syndrome)

Sweet's syndrome is well recognized and not infrequently diagnosed in Spain; however, the range of clinical and pathologic expression may not have been fully realized.

We reviewed 30 consecutive Spanish cases of Sweet's syndrome diagnosed in our department from 1979 to 1990, with special attention to clinical and histopathologic findings.

Distinctive clinical features in our series included oral mucosa lesions in four patients (13%), development of pathergy phenomenon in one case, concurrent nodular lesions resembling erythema nodosum on the limbs in nine cases (30%), and lung involvement in two patients. Infectious disease and drug treatment were recorded as possible triggering factors of Sweet's syndrome in eight and seven patients respectively. Associated underlying systemic disorders were present in 15 (50%) of our patients. The most frequent associations were hematologic neoplasia in four patients, solid neoplasia in two, and chronic idiopathic inflammatory bowel disease in three patients. Dressler's syndrome and sicca syndrome were found in one patient each. Histopathologic studies of skin biopsy specimens obtained at presentation disclosed typical features of Sweet's syndrome in all cases. Epidermal involvement, with variable degrees of spongiosis, exocytosis of polymorphonuclear leukocytes and keratinocyte necrosis, was a prominent feature in 83% of biopsy specimens.

Further characterization of the clinicopathologic spectrum of Sweet's syndrome is necessary as the recognition of the full spectrum of this syndrome will improve our diagnostic abilities and provide a solid clinical basis for prospective studies that allow dissection of the intricate patho-mechanisms involved in this fascinating disorder.