To the Editor.—
We read with great interest the article by Dr Claman1 on the putative importance of mast cells in the integrated view of the pathogenesis of scleroderma. He noted increased numbers of mast cells in the skin of patients with active scleroderma and related this finding to skin fibrosis. Many patients with scleroderma experience lung involvement, usually characterized by fibrosing alveolitis with variable inflammation.2 Therefore, it may be expected that mast cells would be increased in the lungs of those patients with scleroderma who have interstitial inflammation, since mast cells may be increased in lung fibrosis3 and there is an increase in mast cells in the skin of patients with scleroderma.
We studied 8 patients (40 to 63 years old) who had been suffering from skin scleroderma for the previous 15 to 29 years. Four of these patients had an interstitial lung disease