[Linear IgA bullous dermatosis: the importance of a correct differential diagnosis].

Linear IgA bullous dermatosis is an acquired subepidermal blistering disease which belongs to bullous autoimmune diseases, along with dermatitis herpetiformis and bullous pemphigoid. Inflammatory blisters are the main clinical characteristics and the areas of common involvement are: perioral region, abdomen, perineum, buttocks and the interior side of thighs. Essential for the diagnosis is to find by direct immunofluorescence the presence of a linear band of IgA antibodies at the level of the basement membrane. We present the case of a 5 year-old Moroccan girl which arrived at our First Aid Department for bullous dermatitis, localized mainly on the abdomen, legs and thighs. During a short stay in Morocco, a month before, the little girl was stung by an insect and developed bullous dermatitis by a residual lesion. The child was in a good state of health but blood exams showed an increase of total IgE antibodies. The girl was admitted and during her hospitalisation we made a skin biopsy which led to a diagnosis of linear IgA dermatosis. She began a steroid therapy and there was a progressive regression of the lesions. At present, she does not take medicines anymore, she feels well and is submitted to ambulatory medical follow-up.