Rosh Psychiatry Board Practice Exam

In a patient with a history of excessive eating and self-induced vomiting, which lab result is likely increased?

1. Calcium

2. Magnesium

3. Amylase

4. Potassium

The correct answer is: Amylase

In individuals with a history of excessive eating and self-induced vomiting, amylase levels are likely to be elevated. This occurs because the act of vomiting can lead to potential damage of the salivary glands, which produce amylase, an enzyme involved in carbohydrate digestion. In cases where vomiting is frequent and significant, the body can have an increased production or release of amylase due to the stress on the salivary glands from repeated exposure to gastric contents. Additionally, a patient's history of excessive eating, particularly in the case of bulimia or similar eating disorders, can further contribute to the fluctuation in amylase levels. Elevated amylase can serve as a diagnostic marker for such conditions, as it reflects the increased functional activity of the salivary glands in response to recurrent vomiting episodes. While increased levels of other electrolytes like potassium might also be observed in some patients due to vomiting-induced loss and re-compensation, amylase specifically stands out as the marker most directly related to the act of self-induced vomiting in the context provided.