Les lymphangiectasies pulmonaires congénitales (LPC) d’expression néonatale sont rares. Difficile en l’absence de spécificité des signes cliniques et radiologiques, le diagnostic repose sur l’examen anatomopathologique. Nous rapportons le cas d’un garçon né proche du terme, décédé au 15^e j d’une détresse respiratoire néonatale initialement évocatrice de la maladie des membranes hyaline ou d’une infection materno-fœtale. Les données de l’autopsie (dilatation anormale des lymphatiques drainant les espaces interstitiels et sous-pleural) ont établi le diagnostic de LPC qui, bien que rares, doivent être évoquées devant une détresse respiratoire inexpliquée du nouveau-né.

Congenital pulmonary lymphangiectasis (CPL) is a rare condition in neonates characterized by abnormal dilatation of the lymphatics draining the interstitial and subpleural spaces of the lungs. Diagnosis is difficult in the neonatal period because respiratory features and radiological findings are not specific of the disease. Definitive diagnosis of CPL can be made only by pathologic examinations. We report a case of a male near-term neonate presenting with severe respiratory distress at birth. The initial chest X-ray showed frosted glass-like infiltrates with air bronchogram suggesting a maternofetal infection or respiratory distress syndrome. The infant required mechanical ventilation and chest tube insertion for right then bilateral pneumothorax. The child died 15 days later in spite of optimal high-frequency ventilation, bilateral pneumothorax drainage, and hemodynamic support. Autopsy revealed features consistent with the diagnosis of CPL. Although CPL is very rare, we should be aware that it is a possible cause of severe unexplained respiratory distress in neonates.