131I-hippuran clearance value and an attempt of its simple measurement method

Simple measurement method of 131I-hippuran clearance value was deviced by applying theoretical measurement method of 131I-hippuran clearance value, CHipp. The subjects were 43 cases in total of patients with kidney diseases and normal kidneys. Excretion rate in urine of 131I-hippuran at 20 minutes was directly proportional to para-amino-hippuric acid (PAH) clearance value used in comparison, and it showed a significant relationship of r=0.82. Its simple measurement method was deviced and calculated as follows: CHipp = (excretion amount in urine (20 minutes value))/(20 x concentration in plasma (10 minutes value)) (ml/min). 131I-hippuran clearance value and PAH clearance value calculated by this method showed extremely good results, and the coefficient of correlation and CHipp/CPAH clearance ratio was 0.96 and 0.91 +- 0.11 (M +- 1.SD), respectively. These results was enough to be used clinically. Accordingly, this method is possible to calculate approximation value of CHipp very simply by measuring excretion amount in urine after 20 minutes of 131I-hippuran intravenous injection and count per minute in 1 cc of plasma after 10 minutes of intravenous injection. (Kanao, N.)