Pulmonary hypertension associated with systemic lupus erythematosus: predominantly thrombotic arteriopathy accompanied by plexiform lesions

We report an autopsy case of pulmonary hypertension associated with systemic lupus erythematosus in a 48-year-old woman. After 8-year follow-up under a definite diagnosis of systemic lupus erythematosus, she experienced gradually developing exertional dyspnea with palpitation. Her chest x-ray showed clear lung fields with marked cardiac enlargement. A right cardiac catheterization revealed a pulmonary arterial pressure of 74/30 mm Hg (mean: 47). She was treated with repeated plasmapheresis, oral corticosteroid, and immunosuppressant without improvement, and she died suddenly, 23 days after admission. Pathological examination revealed that small pulmonary arteries and arterioles were diffusely involved by florid thrombotic lesions, which were characterized by intimal eccentric fibrous thickening, luminal occlusion with recanalization, and occasional fresh thrombi. In addition, some arteries showed plexiform lesions coexistent with intimal thrombotic lesions. Concentric laminar intimal fibrosis was not seen. No significant parenchymal change was seen. Our study not only adds a rare case of thrombotic pulmonary hypertension associated with systemic lupus erythematosus, but also suggests that plexiform lesions can occur in association with thrombotic arteriopathy.