Severe pulmonary arterial hypertension as initial manifestation of intravascular lymphoma: case report.

Intravascular lymphoma (IVL) is a rare and usually fatal disease that belongs to the class of high-grade malignant lymphomas and which is characterized by proliferation of neoplastic lymphoid cells exclusively within the lumina of small blood vessels. Its polymorphic and nonspecific clinical manifestations make antemortem diagnosis very difficult. We report herein a case of IVL revealed by fatal, precapillary, pulmonary arterial hypertension and associated with long-lasting fever. Extensive investigation of the usual causes of pulmonary arterial hypertension was negative. The diagnosis of intravascular lymphoma was made on postmortem analysis, revealing diffuse and sometimes complete obliterations of the lumina of small blood vessels by large B-cell lymphoma, including pulmonary capillaries. Thus, we propose that IVL must be added to the spectrum of etiologies of subacute pulmonary arterial hypertension, notably in the context of associated fever, both entities requiring emergency diagnosis. For this purpose, blood collected via pulmonary capillary-wedge aspiration for cytologic examination may be associated with right-sided heart catheterization when this latter procedure is suitable.