[Pneumomediastinum as a rare complication in connective tissue disease].

Otherwise known as mediastinal emphysema, pneumomediastinum (PNM) in connective tissue diseases is a rare clinical entity. Few cases have been described in the literature. In fact, it only exceptionally complicates the evolution of connective tissue diseases. In this paper report, two cases of spontaneous PNM secondary to scleroderma and Sjogren's syndrome. Based on the data in the literature, we discuss the etiology, frequency of occurrence, and the pathophysiological mechanisms of this unusual complication.