We present the case of a 67-year-old Caucasian woman, who had been diagnosed 9 months before with primary immune thrombocytopenia. She had developed painful palmar lesions 1 week earlier, but had no fever or other accompanying symptoms. We observed erythematous violaceous plaques on the ulnar border of both hands, with a pustule of about 4cm on the right (Fig. 1a). A biopsy showed a dense dermic neutrophilic infiltrate, with marked edema, and no vasculitis (Fig. 1b). Cultures to detect bacteria, virus and fungi produced no evidence. Except for the patient's thrombocytopenia, her complete blood count was normal, and laboratory testing found a C-reactive protein of 1mg/L. A study of the extension ruled out an underlying neoplastic disease. She responded completely to oral prednisone at 0.5mg/kg/day for 2 weeks, with no recurrence after 1 year of follow-up. The neutrophilic dermatosis of dorsal hands, recently described,1 consists of the presence of erythematous violaceous plaques on acral sites, with blisters or pustules, histologically constituted by a dermic neutrophilic infiltrate, with or without association of leukocytoclastic vasculitis.1–8 Generally, there is no respiratory involvement, fever or laboratory abnormalities, which differentiates it from conventional Sweet's syndrome.1–5,9 It has been associated with hematologic neoplasms (frequently, myelodysplasia and leukemias), carcinomas, inflammatory bowel disease and arthritis, among other conditions.1–5 Available data show a rate of association with hematological diseases similar to that of classical Sweet's syndrome.4,9,10 The case we report is the first that associates it with primary immune thrombocytopenia, a disease that has been found exceptionally in conventional Sweet's syndrome.10 Our case, although the involvement is palmar, has a characteristic pustular morphology. Thus, we consider the term acral or hand neutrophilic dermatosis to be more correct.9 The differential diagnosis should include skin infections, arthritis, vasculitis and cutaneous lymphomas. It responds well to oral corticosteroids or dapsone, and its recurrence is occasional.1–5

Fig. 1.

(a) A large pustule in an erythematous violaceous plaque on the palm of the patient's hand. (b) Hematoxylin and eosin (10×). Dense dermic neutrophilic infiltrate with marked edema, without leukocytoclastic vasculitis.

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