[The clinical value of the hydroxyproline excretion in 24 hour urine compared to other laboratory diagnostic parameters in ankylopoietic spondylarthritis].

Hydroxyproline provable in the urine of man is regarded as indicator of the collagen metabolism. In 40 patients with ankylopoietic spondylarthritis the excretion of hydroxyproline in the 24-hour-urine was determined with the help of Stegemann's method. With 27.5 mg for the total hydroxyproline and 2.6 mg for the free hydroxyproline in the group of patients statistically significantly higher values were established than in a comparative group of 52 persons (20.1 or 0.6 mg, respectively). In patients with higher activity of the process (anamnestically, clinically) the excretions were larger than in patients with lower activity. That in this reflects also the temporary factor is to be concluded from the higher excretion rate in patients with a shorter duration of the disease and a low rate with a longer course. In comparison to the insignificant diagnostic relevancy of other acute-phase-reactions (BSR, CRP, number of leukozytes, blood protein fractions) from this results the conclusion that the determination of hydroxyproline may be used for the diagnostics of activity and also for the early diagnostics. By the temporary and technical-material expenditure, however, its use is limited in the routine practice.