Alkaline urine and eating disorders

Nutrition Research Newsletter, April, 1991

ALKALINE URINE AND EATING DISORDERS Alkaline urine is usually associated with Proteus urinary tract infections or with rare conditions such as metabolic alkalosis or excessive ingestion of certain drugs. Physicians from Long Island Jewish Medical Center have now reported in a letter to the Editor of the American Journal of Diseases in Children that alkaline urine may also occur in adolescents with eating disorders.

Urine samples were obtained from 46 patients with earing disorders and 28 control subjects who sought treatment for other problems at an adolescent medicine clinic. The mean urine pH of the eating disorder patients was 6.8, significantly higher than the value of 5.9 found in controls. Seventeen of 46 patients with eating disorders and alkaline urine (pH greater than 7), but only one of 28 controls did. The specificity of alkaline urine as a diagnostic test for eating disorders was 96%, but the sensitivity was only 37%.

The authors believe that the presence of alkaline urine may be of diagnostic value as a "flag" to signal the possibility of an eating disorder. However, because the test has low sensitivity, the absence of alkaline urine cannot be used to rule out this diagnosis. "The finding of alkaline urine in an adolescent is significant and should always be investigated."

Martha R Arden et al, Alkaline Urine is Associated with Eating Disorders [Letter], American J Diseases Children 145(1):28-30 (Jan 1991) [Correspondence: Martha R Arden, MD, Division of Adolescent Medicine, Schneider Children's Hospital, Long Island Jewish Medical Center, Albert Einstein College of Medicine, New Hyde Part NY 11042]