ABSTRACT
Diffuse pulmonary lymphangiomatosis is an extremely rare congenital lesion affecting the lymphatic pulmonary system. It is charcterized by a multifocal proliferation and a pulmonary lymphatic vessels dilatation. It is essentially observed in newborns and infants. The diagnosis is based on histological findings. The purpose of this article is to describe the main clinical and pathological features of this rare entity difficult to diagnose. We report a case of a 19-year old girl who presented with a 2- month standing dyspnea. Radiographic findings consisted in a soft tissue infiltration and thickening in the two lobes. Based on histological and immunohistochemical findings, the diagnosis of diffuse pulmonary lymphangiomatosis was retained. Diffuse pulmonary lymphangiomatosis is a difficult diagnosis which can be confused with lymphangioleiomyomatosis. Its worse prognosis could be improved by an early diagnosis enabling the use of interferon alpha 2B at the proper time