Rosh Psychiatry Board Practice Exam

The appropriate laboratory test for evaluating a patient diagnosed with anorexia nervosa is the measurement of 25-hydroxyvitamin D level. Patients with anorexia nervosa frequently exhibit nutritional deficiencies due to inadequate dietary intake. Vitamin D deficiency is common in this population because of reduced food variety and limited sunlight exposure, particularly if the individual is engaging in restrictive eating behaviors. Monitoring vitamin D levels is important, as deficiency can lead to complications such as osteopenia or osteoporosis, which are of particular concern in individuals with anorexia due to already low bone mineral density.

In contrast, while other tests might yield information about different aspects of a patient's health, they are not as directly relevant to the acute evaluation of nutritional status and potential deficiencies associated with anorexia nervosa. Aldosterone levels are usually tested in cases of suspected adrenal disorders, while creatine kinase levels are often checked for muscle damage or inflammation, neither of which are primary concerns in anorexia nervosa evaluation. Hemoglobin A1c is primarily used to assess long-term glucose control in individuals with diabetes and does not provide relevant information regarding nutritional status in anorexia nervosa.