Scleroderma: Dermal Amino Acid Composition with Particular Reference to Hydroxyproline.

Samples of dermis from patients with scleroderma and from control subjects were analyzed for hydroxyproline chemically and, in a more limited series, for all ammo acids by ion exchange procedures. Dermis from scleroderma patients had a mean hydroxyproline concentration of 8.2 and 8.7 mg per 100 mg of dry, fat-free tissue compared to 10.0 and 9.8 mg for controls, determined chemically and chromatographically, respectively. It is suggested that a dilution of collagen with another substance may cause the lower values obtained in the diseased state.