A 36 year-old female with history of bulimia nervosa, bipolar disorder and borderline personality disorder presented to the emergency department after she woke up with painful spasm of bilateral hands. She had been vomiting multiple times daily for the past few days but denied any paresthesia, numbness, weakness, tingling, diarrhea, laxative or diuretic abuse. She had 18 years history of bulimia nervosa, primarily involving purging behaviors with self-induced vomiting and excessive exercising. Home medications included quetiapine, valproate and alprazolam. Her body mass index was 20.7 kg/m2. Vital signs were respiratory rate of 21/minute, pulse 101/minute, blood pressure 113/78 mmHg and temperature 98.2 F. Physical examination revealed dry oral mucosa, poor oral dentition, classic carpopedal spasm at bilateral wrists and scarring on dorsum of right hand. Rest of the examination was unremarkable. Labs revealed hypocalcemia (ionized calcium 0.88 ng/dl), hypokalemia (potassium 2.8 mEq/L), hypomagnesemia (magnesium 1.6 mEq/L), hypochloremia (chloride 78 mEq/L), hypophosphatemia (phosphorus 1.6 mg/dL), metabolic alkalosis (serum bicarbonate 34.5 mEq/L), acute kidney injury (serum creatinine 2.49 mg/dl, baseline of 0.9), leukocytosis (WBC 15,700/mm3) and albumin 4 g/dL. Electrocardiogram showed normal sinus rhythm with prolonged QTc of 550 ms. Urine drug screen was positive for cocaine as she was snorting cocaine the night prior. She was resuscitated with intravenous fluids and repleted with electrolytes leading to resolution of her carpopedal spasm, leukocytosis, electrolyte and EKG abnormalities.
Discussion:
Bulimia nervosa is an eating disorder characterized by recurrent episodes of binge eating and inappropriate compensatory behaviors like self-induced vomiting, excessive exercise, laxative or diuretic abuse. It is 10 times more common in females. Finding of dental erosions, parotid enlargement and scarring/calluses on dorsum of hand should raise suspicion of this disorder. It may be associated with various gastrointestinal, cardiac or reproductive complications. Electrolyte imbalances reflect more severe purging and predict poorer outcome. Acute hypocalcemia along with metabolic alkalosis, hypomagnesemia and hypokalemia can cause tetany due to increased neuromuscular irritability, which when severe manifests as carpopedal spasm, laryngospasm or seizures. Though most cases are mild and can be managed as outpatient, severe electrolyte abnormalities and hemodynamic instability warrant inpatient management. Combined pharmacotherapy and psychotherapy is mainstay of treatment of bulimia nervosa and full recovery may occur in upto 50% cases over 10 years, however relapses are common.
Conclusions:
Bulimia nervosa is an eating disorder which when severe can cause a wide array of electrolyte abnormalities and medical complications. Bulimia, to the extent of causing severe electrolyte disturbances and subsequent carpopedal spasm has been rarely reported in literature. Bulimia nervosa should always be considered in middle aged females with unexplained hypokalemia, metabolic alkalosis and other electrolyte abnormalities.