RESUMEN
INTRODUCTION: Sweet's syndrome was described for the first time in 1964. It is usually described in adults and remains rare in children. We report a case in a 23 month-old infant. OBSERVATION: A 23 month-old boy presented with diffuse papular, edematous annular plaques surrounded by vesicles and bullas. Laboratory examinations revealed neutrophilic polynuclear hyperleukocytosis, anemia and an inflammatory syndrome. The myelogram was rich and the abdominal sonography normal. Oral corticosteroids (2 mg/kg/d) led to spectacular improvement. After 19 days' treatment, the boy developed cervical adenopathies and hepatomegaly. The second myelogram was normal. Evolution under corticosteroids was good. DISCUSSION: Sweet's syndrome is exceptional in infants. The frequent association with a malignant blood disease should prompt appropriate investigations and prolonged surveillance. Systemic corticosteroid therapy is the reference.