[Pulmonary involvement in systemic scleroderma. Part II. Isolated pulmonary arterial hypertension, bronchopulmonary cancer, alveolar hemorrhage]

Pulmonary interstitial fibrosis is the most frequent cause of lung disease in systemic sclerosis. However, other pulmonary complications exist, including lung cancer, alveolar hemorrhage, and in particular isolated pulmonary arterial hypertension, which is still considered the bête noire as regards this disease.

The prevalence of pulmonary arterial hypertension has been reported to range from 5 to 60% in cases of systemic sclerosis; isolated pulmonary arterial hypertension has been principally observed in subjects with a ten-year history of limited forms of the disease. As the patient remains asymptomatic for a long period, with nonspecific respiratory clinical manifestations, the diagnosis is made at a much later stage in the course of the disease. The diagnostic method of choice is echocardiography-doppler, which should be performed during the preliminary investigation, and at follow-up. The prognosis is poor, and patient survival rate at 2 years after onset of symptoms amounts to 40%. To date, no curative therapy for pulmonary arterial hypertension has yet been found.

A knowledge of the mechanisms involved in the development of isolated pulmonary arterial hypertension is essential to the determination of new and relevant therapeutic strategies. Vasodilatory treatment, notably calcium channel blockers, prostacyclin and analogs such as iloprost, may be effective at an early stage of the disease before the appearance of permanent vascular damage.