Clinical Evaluation of Kidney Function

COMPARED to the use of inulin clearance as a measure of glomerular function, no single test of renal tubular function can be as specific since the renal tubules carry out many different functions. Studies of the maximal ability of the tubules to reabsorb glucose (TmG) or to secrete para-amino-hippurate (TmPAH) are, in fact, approximate indexes of functional tubular mass, but such studies are too complex for clinical purposes. As a substitute, tests of concentration and dilution and phenolsulfonphthalein (PSP) excretion have often been used to detect renal tubular damage early in its course and to follow . . .