We performed a retrospective analysis of the records of 16 patients diagnosed in our dermatology service as Sweet's syndrome (SS), with the aim of describing their clinical findings and associations, and comparing our results with previous ones. The mean age was 51, and 82% were female. A previous infection was recorded in 5 cases (31%) (gastroenteritis, primary pulmonary tuberculosis, upper airways infection, wound infection, and streptococcal pharyngitis). Two patients (12%) suffered from a malignant neoplasia (acute myeloid leukemia and prostatic neoplasia), another patient had a coincident bout of acute ulcerative colitis with pyoderma gangrenosum, and a third one referred previous ingestion of diclofenac and intense sun exposure. Most patients had their lesions localized on the upper extremities (75%), fever was present in 8 cases (50%), arthralgia in six (37%), and erythema nodosum in five (31%). The most frequent laboratory finding was an elevated sedimentation rate (93% had values over 20 mm/h), and only 44% of patients had leukocyte counts over 10 x 10(9)/l. Urinanalysis was abnormal in one third of the patients, and chest roentgenograms, performed in ten patients, were all normal. Most of the patients were treated with low doses of oral prednisone (30 mg/day) with good results. The disease recurred in 25% of the patients.