Urinary hydroxyproline, creatinine and urea excretion during the growth of five siblings

Urinary excretions of hydroxyproline, creatine and urea in 24 h specimens from 5 siblings have been determined monthly from 1971 to 1976 together with the measurements of body height and body weight. Changes with age in the urinary levels of these substances are in good agreement with those from cross-sectional studies in various age groups of children. Wide fluctuations of excretion levels occurred. The creatinine coefficients did not remain constant even over short periods. Menarche was observed shortly after the peak of hydroxyproline excretion at puberty. The hydroxyproline excretion pattern is similar to that of hydroxyproline index proposed by Whitehead, and it is quite different from that of hydroxyproline ratio.