A 27-year-old woman comes to the office due to worsening generalized weakness. The patient has also had occasional palpitations, muscle cramps, abdominal bloating, and constipation. She reports no chronic medical conditions, but 6 months ago she was hospitalized due to bloody emesis and was found to have a Mallory-Weiss tear. She does not use tobacco, alcohol, or illicit drugs. Temperature is 37 C (98.6 F) , blood pressure is 110/70 mm Hg, pulse is 90/min, and respirations are 10/min. BMI is 24.6 kg/m². Physical examination shows anicteric sclera, dry oral mucosa, dental caries, and bilateral swollen cheeks. The lungs are clear on auscultation and heart sounds are normal. The abdomen is soft and nontender with no organomegaly. There is mild lower extremity edema. Skin is dry without any rashes. Muscle strength is mildly decreased throughout. Which of the following sets of findings are most likely to be present in this patient?

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The physical examination findings of dry skin, dental caries, bilateral swollen cheeks (parotid gland enlargement), and history of a Mallory-Weiss tear are consistent with surreptitious, self-induced vomiting, suggesting a diagnosis of bulimia nervosa (BN). Because patients with eating disorders often attempt to hide their condition, physical examination and laboratory assessment are often key to making the diagnosis. Excessive vomiting, which is commonly seen in BN, causes multiple metabolic derangements. Loss of hydrochloric acid and potassium in the vomit results in a hypokalemic, hypochloremic metabolic alkalosis (ie, elevated pH, low chloride). Dehydration and volume contraction result in activation of the renin-angiotensin-aldosterone system (RAAS), which causes secondary hyperaldosteronism and further worsens these abnormalities by increasing renal hydrogen and potassium excretion in exchange for sodium and subsequent water retention. As seen in this patient, peripheral edema may occur due to third spacing of retained fluid. renin-angiotensin-aldosterone system (RAAS) In addition to the characteristic findings associated with excessive vomiting (eg, dental caries, parotid gland enlargement), patients may also have symptoms related to volume contraction (eg, dizziness, orthostasis) and electrolyte abnormalities (eg, arrhythmias, weakness, muscle cramps, constipation). (Choices B, C, D, and E) Self-induced vomiting in BN can result in a hypochloremic, hypokalemic metabolic alkalosis indicated by increased blood pH and decreased serum chloride. Aldosterone is increased due to upregulation of the RAAS. Educational objective: Self-induced vomiting in bulimia nervosa results in dehydration and volume depletion, resulting in secondary hyperaldosteronism and a hypokalemic, hypochloremic metabolic alkalosis. Symptoms may occur as result of volume contraction (eg, dizziness, orthostasis) and electrolyte abnormalities (eg, arrhythmias, weakness, muscle cramps, constipation). References: Bulimia nervosa - medical complications. (http://www.ncbi.nlm.nih.gov/pubmed/25866627) Medical complications of anorexia nervosa and bulimia. (http://www.ncbi.nlm.nih.gov/pubmed/26169883)

A 27-Year-Old Woman Comes to the Office Due to Worsening