The urinary excretion and thyroid uptake of iodine in renal disease.

Radioactive iodine has proved itself a most useful tool in the assessment of thyroid function and since its introduction in 1938 by Hertz, Roberts, and Evans (1) a voluminous literature on this subject has developed, much of which has been well summarized by Skanse (2) in his monograph. Although various workers have noted that there is a delayed excretion of the isotope in renal disease which probably invalidates any measurements of urinary excretion of radio-iodine or calculations derived from such measurements as a means of indirectly assessing thyroid function, relatively little investigation of the effect of renal lesions on the more direct measurements of thyroid function with radio-iodine has been carried out. McConahey, Keating, and Power (3) have noted an apparently decreased rate of accumulation of radio-iodine by the thyroid gland, a finding generally indicative of depressed thyroid function. It thus seemed of interest to further investigate this problem to see firstly if renal disease in any way invalidates the use of tracer doses of radio-iodine as a diagnostic aid in assessing thyroid function, and secondly, with the aid of the isotope, to study some phases of iodine metabolism and utilization in subjects with renal disorders.