Renal complications in anorexia nervosa

Anorexia nervosa is a malady with possible long-lasting physiological consequences. Among these, little is known about the renal effects, which remain rarely investigated.

A literature review was conducted using electronic databases and manual search of relevant articles, discussing the renal impacts of anorexia nervosa.

Renal failure has been described in malnourished patients, but the optimal non-invasive tool to assess the glomerular function rate in this population needs to be further evaluated. Significant disruptions in osmolar regulation, even in the absence of potomania, arise from multiple factors: hypothalamic dysfunction, intrinsic renal insufficiency, and use of psychotropic medications. Urinary urgency and nocturnal enuresis are frequent symptoms, rarely reported by patients. Among hydroelectrolytic disorders, hypokalemia is the most frequent, especially in settings of vomiting or medication misuse. Hyponatremia, hypomagnesemia, and hypophosphatemia may also be encountered. Urinary lithiases are relatively frequent as a consequence of dehydration, laxative use, or both.

Investigation and follow-up of the renal function are essential in patients with an eating disorder, especially when the illness has been present for a long time.