The quantitative measurement of tubular chlormerodrin binding as an index of renal function: a study of 400 cases.

We have studied and found valuable a numerical value best designated as the "renal chlormerodrin uptake". This represents not a transient state, like the renogram, but a measurement of the biological ability of the renal tubules to firmly bind (203)Hg chlormerodrin presented to them as a very small standard dose passing through the kidney. Normal kidneys bind a remarkably fixed portion, and there is a consistent parallel between retention and tubular function.This binding, expressed for each kidney as a percentage of the normal, provides an easily measured value which allows isotopic renal measurements made from day to day and from year to year, on various individuals, to be accurately compared.These uptake values may be used to measure individual organ function or, by their addition, to evaluate the total renal function possessed by that patient. The utility of such uptake values goes beyond the conventional assessment of renal flow in hypertension, and is applicable to most forms of renal dysfunction, including trauma.Determination of the renal uptake at three to four hours fits well into a standard set of procedures which also includes the renogram, the renal scan, the local quantitation of scan areas, and the intravenous pyelogram. It requires only a few additional minutes, and no additional instrumentation or radiopharmaceuticals.