Anorexia nervosa: from purgative behaviour to nephropathy. a case report

BACKGROUND Individuals who suffer from Anorexia Nervosa refuse to maintain a minimally normal body weight, are intensely afraid of gaining weight and exhibit a significant disturbance in the perception of the shape and size of their body. Postmenarchal females with this disorder are amenorrohic. In the Binge-Eating/Purging subtype individuals regularly engage in binge eating and purging behaviour (i.e self-induced vomiting or misuse of laxatives, diuretics, or enemas).Hypokalaemia is often seen in chronic Anorexia Nervosa, especially that of the purging type (ANp), and, as well as electrocardiographic anomalies, this can lead to tubulointerstitial nephritis (hypokalaemic nephropathy) with typical histological characteristics. The physiopathological mechanisms behind this damage are linked to altered stimulation of vasoactive mediators, and to the ammonium-mediated activation of the alternative complement pathway. However, it has not yet been ascertained whether a variant of the pathway specific for ANp 1, exists. CASE PRESENTATION We describe herein a case of hypokalaemic nephropathy in a patient affected by chronic ANp who presented to our Centre for Eating Disorders. CONCLUSION Hypokalaemia can provoke cardiovascular alterations as well as muscular and renal complications, and thus potential renal damage needs to be investigated in patients suffering from long-term purgative anorexia.