Which statement about purging-type anorexia is consistent with the described labs?

Which statement about purging-type anorexia is consistent with the described labs?

• A. Low chloride and high bicarbonate
• B. High chloride and low bicarbonate
• C. Normal chloride and normal bicarbonate
• D. Low bicarbonate and high chloride

Answer: (A)

Purging-type anorexia causes loss of gastric acid through vomiting, which leads to metabolic alkalosis. When HCl is lost, chloride levels fall (hypochloremia) while the kidneys retain and reabsorb bicarbonate to maintain volume and pH, so bicarbonate rises. This combination—low chloride with high bicarbonate—is the pattern you’d expect with vomiting-induced alkalosis. The other patterns don’t fit: a high chloride would not accompany vomiting, and normal or low bicarbonate would not reflect metabolic alkalosis.

Purging-type anorexia causes loss of gastric acid through vomiting, which leads to metabolic alkalosis. When HCl is lost, chloride levels fall (hypochloremia) while the kidneys retain and reabsorb bicarbonate to maintain volume and pH, so bicarbonate rises. This combination—low chloride with high bicarbonate—is the pattern you’d expect with vomiting-induced alkalosis. The other patterns don’t fit: a high chloride would not accompany vomiting, and normal or low bicarbonate would not reflect metabolic alkalosis.