[Schnitzler's syndrome. A new case].
A new case of Schnitzler's syndrome is reported in a 72-year old man hospitalized for severe deterioration of his general condition associated with recurrent ancient urticaria. Paraclinical examinations, which showed inflammatory syndrome, bone condensation and IgM monoclonal gammapathy, led to the diagnosis of Schnitzler's syndrome, first described in 1972. Twenty-two cases have now been published, characterized by vasculitic urticaria, osteosclerosis and IgM macroglobulinaemia. There is also severe inflammatory syndrome and the other immunological examinations are normal. Recent studies suggest the possibility of uncontrolled activity of interleukin-1 alpha. The condition is chronic and usually benign, but the fear of malignant transformation in the long term makes the therapeutic choice difficult.