Evaluation of the Efficacy of Anti-Rejection Therapy Using the Quantitative Analysis of Guanidinoacetic Acid (GAA) Urinary Excretion as a Guide

Due to insufficient recognition of rejection crises in kidney transplants, rejection of grafts is a common complication. When it is difficult to make diagnoses using conventional biochemical parameters, histopathological studies of grafts have been undertaken to clarify the clinical events. Even in cases of successful biopsies, consecutive procedures are not possible. Therefore, since the urinary excretion of GAA reflects the metabolic functioning of the kidney, we examined the daily level of GAA in urine after transplantation and considered the feasibility of using this measure as a guide to the early detection of rejection and whether or not the amount of GAA urinary excretion could contribute to the evaluation of the efficacy as well as the sufficiency of anti-rejection therapy.