[Interstitial lung disease in collagen vascular diseases. Diagnostic and therapeutic implications of non-specific interstitial pneumonia].

Interstitial lung disease (ILD) is among the most common organ manifestations in collagen vascular diseases and can be a major determinant of the long-term prognosis. Early diagnosis rests mainly on spirometry, including measurement of the CO diffusion capacity, and high-resolution computed tomography (HRCT). The most common histopathology of ILD in collagen vascular diseases is the non-specific interstitial pneumonia (NSIP) pattern. It is distinguished from the usual interstitial pneumonia (UIP) pattern, which is most common in idiopathic lung fibrosis, by a significant inflammatory component, a distinct HRCT pattern, with often prominent ground-glass opacities, and a distinct cell pattern on bronchoalveolar lavage (BAL) with an often prominent lymphocyte component. Therapeutic experience is heterogeneous but evidence is accumulating suggesting that NSIP in the collagen vascular diseases is amenable to immunosuppression. Rapid clinical and/or radiological deterioration, reflecting inflammatory activity, appears to mark those patients who are most likely to benefit from cyclophosphamide therapy.