Creatine Excretion in Artificial Hyperthyroidism.

Abstract

An attempt was made to produce creatinuria in 3 individuals by the ingestion of thyroid extract. Palmer 1 has recently reported that creatine is excreted in the urine of patients suffering from hyperthyroidism and that under iodine medication this excretion tends to disappear. Creatine determinations were made by the method of Folin. 2 Tests for acetone and diacetic acid in the urine were negative. The first subject, an arterio-sclerotic individual of 63, having an initial basal metabolic rate of —22, was placed on a meat-free diet with 1.25 gm. of protein per kilogram of body weight. After observing his creatinine excretion he received gr. 19 of thyroid extract (Armour) over a 6-day period, then gr. 6 daily over a 4-day period, then gr. 9 daily for 8 days, and finally gr. 6 daily for 16 days. Creatine appeared in the urine on the second day of thyroid administration, disappeared on the twelfth, and then rose to a maximum excretion of 483 mg. on the twentieth day of the experiment. This coincided with a B.M.R. of +33. When the dose of thyroid was decreased to gr. 6 daily and 1 cc. of Lugol's solution was given twice a day for 7 days the creatine excretion fell to 100-150 mg. a day. This was not an iodine effect, however, as continued administration of thyroid without iodine was not sufficient to maintain metabolism at its previous high levels or to increase creatine excretion. The average daily excretion of creatinine amounted to 1350 mg. During the experiment this fell to a level averaging 1050-1100 mg. The complete figures are shown in the accompanying chart.

The second subject, a normal male of 29, having an initial B.M.R. of −5, on an unrestricted diet, took daily doses of thyroid extract (Burroughs and Wellcome) increasing from gr. 10 to gr. 35. Urine collections were irregular but there was a creatine excretion of 36-221 mg. per day in the earlier part of the experiment without significant changes in the excretion of creatinine.