Diffuse interstitial lung diseases: a histochemical approach.

72 cases of diffuse interstitial lung diseases were observed from 1969 to 1976. Specimens removed from 47 patients were subjected to the whole spectrum of reactions. According to variation of both elastin and collagen, the following groups were outlined: group A: mycobacteriosis, farmer's lung, sarcoidosis and silicosis; group B: chronic eosinophilic pneumonia, lymphocytic interstitial pneumonia, post-tuberculous pulmonary fibrosis, and group C: X-ray pneumopathy, desquamative interstitial pneumonia, sclerodermic pneumopathy and chronic pulmonary fibrosis (primary chronic fibroadenomyosis). Each of these groups presents a close relationship between histochemical, radiological, clinical and functional findings.