Effects of Pituitary Antidiuresis on Non-Cardiac Edema

From a previous study, describing the induction of pituitary antidiuresis in non-edematous subjects, 1 we were impressed by the magnitude of the net loss in body weight at the end of the recovery period. The obvious fact, that the reduction in weight which follows withdrawal of the antidiuretic agent is due under these conditions to loss of body water with its accompanying mineral elements, suggested the desirability of determining the effects of the procedure on the water and mineral exchanges in the presence of edema.

This has been done in 2 cases of typical lipoid nephrosis, one of chronic glomerulonephritis with superimposed nephrosis and one of edema of undetermined etiology. The total serum proteins were low in these subjects at the time of the tests. The case of edema of undetermined cause differed from the other 3 in showing no proteinuria and no increase in the blood lipoids. Throughout the entire period of observation all 4 patients were maintained in the metabolism ward under practically uniform conditions as regards room temperature and humidity, diet and routine for obtaining the body weight and for collecting samples of the excreta. The total water exchange was determined according to the method outlined by Newburg and Johnston. 2 After a preliminary control period of several days on a standard diet relatively low in NaCl, the patient was given a medium-sized dose of the antidiuretic pituitary extract (pitressin P. D.) subcutaneously at 3-hourly intervals for one or 2 days, the exact body weight being measured every 6 hours. After this had been increased by from 3 to 5% due to water storage, the pitressin was discontinued. Balances for the following mineral elements were determined: Na, K, Ca, Mg, CI, N, S and P. The entire procedure was carried out on 2 occasions for each patient.