[Hypopotassemia and prolongation of the Q-T interval in a patient with severe malnutrition caused by bulimia and post-prandial vomiting].

Patient L.A. (f., 20 yrs), affected by bulimia and self-induced vomiting, was hospitalized because of severe malnutrition (BMI 13.1), hypopotassemia (2.8 mEq/l) and prolonged QTc interval (0.469"). Intensive care treatment aimed to normalize mineral balance mainly serum potassium, consisted of administering e.v. potassium (mg 2346/day), magnesium (mg 72/day), calcium (mg 80/day), phosphorus (mg 769/day), chloride (mg 710/day), iron (mg 40/day). Dietary treatment was deliberately chosen to be slightly above minimum energy requirements in order to avoid possible side effects of forced hyperalimentation. The patient, immediately after hospitalization, interrupted vomiting and 2 wks later weight increased by 5 kg (from 34.9 kg to 40.0 kg). On the other hand normalization of serum potassium levels was slow and QTc interval reached normal range only after the 10th day of treatment (0.447"). This case supports the hypothesis that major ECG abnormalities may be present in severe malnutrition due to anorexia nervosa or bulimia with self-induced vomiting. The dangers of these complications were substantiated by the fact that intensive care treatment allowed prompt body weight recovery but normalization of electrolytic balance and cardiac function was very slow. For such patients, electrocardiographic monitoring should be routine.