STUDIES IN SERUM ELECTROLYTES. XVI. CHANGES IN THE SERUM AND BODY FLUIDS IN ANOREXIA NERVOSA

Abstract

Studies of the changes in composition and distribution of the body fluids and serum electrolytes were made in a patient with anorexia nervosa. These have been compared with similar studies previously reported in a severely emaciated individual who had undergone a voluntary fast for a period of 45 days. The concns. of serum chloride were remarkably decreased in both individuals. The decreased concns. of chloride were compensated by increases in the bicarbonate. Although the concns. of serum total base were decreased in both subjects, the decreases of total base were much less than those of chloride. It appears that the factors regulating the serum electrolytes are more concerned with maintenance of normal distribution of cations than of anions. The concns. of serum Mg were increased in both individuals. The concns. of serum albumin, cholesterol esters, uric acid, and creatinine were increased in both subjects. The serum vol. in each subject was increased when calculated in relation to actual wt., but was decreased when estimated in relation to the normal wt. The vol. of extracellular fluid was decreased in the patient with anorexia nervosa. In the fasted subject, the vol. of extracellular fluid was increased in relation to his actual wt., but was within the normal range when calculated in relation to his prefasting wt. The cardiac output (ballisto-cardiographic method) was increased in each subject when estimated in relation to actual wt., but was normal when estimated in relation to ideal wt. The patient with anorexia nervosa continued to excrete Cl in the urine even when the concn. of serum Cl was below 60 mEq./l. Measurements of Cl balance made during a period of intravenous admn. of NaCl in the patient with anorexia nervosa showed a positive Cl balance for the first 3 days; during this period the concn. of serum Cl increased from 64.0 to 94.0 mg./l. The patient with anorexia nervosa showed increased sensitivity to insulin, lowered basal metabolic rates and decreased urinary excretion of estrogens, gonadotropins and neutral 17-ketosteroids. These findings suggest functional insufficiency of the anterior pituitary, gonads, and perhaps of the thyroid and adrenal cortex. The relationship between the syndrome of anorexia nervosa and functional insufficiency of the endocrine system is briefly discussed.