[Diffuse pulmonary infiltration at the onset of Waldenström's disease].

The case of an 52 years old female presenting dyspnea and pulmonary infiltration is reported. A transbronchial biopsy showing a lymphomatous infiltrate with immunohistochemistry using anti-IgM antibody on paraffine embedded section helped to diagnose. A monoclonal increase in seric immunoglobin M, led to the diagnosis of Waldrenström's macroglobulinemia. An initial therapeutic response to Chlorambucil was obtained. But a quick recurrence was observed, with an increase of seric IgG.