Progressive systemic sclerosis.

The pulmonary manifestations of progressive systemic sclerosis (PSS) are important determinants of a patient’s prognosis. Although the etiology and pathogenesis of PSS are unknown, it is recognized that this is a complex disease; it is likely that different genetic susceptibilities and environmental exposures lead to the disease in different individuals. Individuals with diffuse PSS tend to develop interstitial pneumonia, most commonly fibrotic non-specific interstitial pneumonia. Isolated pulmonary hypertension is frequently seen in individuals with limited scleroderma. Screening for these forms of lung disease with high-resolution computed tomography, pulmonary function tests, and echocardiography is important, given the availability of therapeutic options. Scleroderma, literally hard (sclero) skin (derma), is a systemic disease with the potential for destructive visceral involvement in addition to disfiguring cutaneous lesions. Descriptions of the skin changes in systemic sclerosis date back to Hippocrates. However, it was not until the twentieth century that Goetz described the visceral manifestations of the disease, providing the term ‘systemic sclerosis’. Progressive systemic sclerosis (PSS) has been reported throughout the world, but the prevalence of the disease remains unknown. In the United States, the prevalence is estimated to be 300 000. PSS affects women more commonly than men at a ratio of approximately 4:1. Although people of any age may be affected, the onset of disease usually occurs in the fourth through sixth decades of life. Studies vary in the reported prevalence of lung disease in PSS (given differing definitions of pulmonary involvement); however, using the most sensitive diagnostic modalities available, as well as evidence from autopsy studies, most (B70%) PSS patients have lung disease. The pulmonary manifestations have been shown to vary with ethnicity; in blacks and Asians, there is a higher prevalence of lung disease which is also more severe and accelerated than in Caucasians. The two primary forms of lung disease, fibrotic interstitial pneumonia and pulmonary hypertension, play a critical role in PSS patients’ prognosis. In fact, lung disease increases the risk of death at least twofold.