A 32-year-old woman comes to the office due to feeling down for the past several months. The patient has had persistent tiredness, lack of motivation, memory impairment, and loss of libido. She also has had anorexia but reports an unusual craving for foods like salty pretzels or potato chips. Menses occur at regular intervals. The patient does not use tobacco, alcohol, or illicit drugs and works as a fashion designer. Blood pressure is 110/62 mm Hg and pulse is 88/min. BMI is 19.8 kg/m² with weight of 54 kg (119 lb), which is 15 kg (33 lb) lower than her previous weight. The lungs are clear on auscultation and heart sounds are normal. The abdomen is soft and nontender with no organomegaly. There is decreased axillary and pubic hair. Mental status examination reveals a restricted affect. She has no suicidal ideation. Which of the following is most likely to establish the diagnosis in this patient?

Question

Quizplus · Accepted Answer

Explanation: In the evaluation of depression, medical causes of depressed mood should always be considered. Although this patient's fatigue, anorexia, memory impairment, lack of motivation, and loss of libido can be attributed to major depressive disorder (MDD), salt craving and reduced body hair are suggestive of primary adrenal insufficiency (PAI) (also known as Addison disease). PAI usually results from autoimmune destruction of the bilateral adrenal cortex and presents with the following: adrenal cortex Mineralocorticoid deficiency causes renal salt wasting, with hypotension, weight loss, hyponatremia, hyperkalemia, and dietary salt craving. Glucocorticoid deficiency leads to fatigue, anorexia, and many psychiatric manifestations of adrenal insufficiency (eg, irritability, depressed mood). It also contributes to hypotension. Androgen deficiency leads to loss of libido and suppression of secondary sexual characteristics (eg, reduced pubic hair). These effects are typically only seen in women because androgen production still occurs in the testes of men. In patients with suspected AI, salt craving and hyperpigmentation are specific for PAI and help differentiate it from secondary AI. The diagnosis of PAI is made by stimulation testing with cosyntropin, a synthetic form of ACTH. Low production of cortisol following cosyntropin administration is diagnostic of PAI. (Choice B) CT scan of the chest, abdomen, and pelvis can help identify malignancy. Small cell lung cancer and Hodgkin lymphoma can rarely cause paraneoplastic limbic encephalitis, which manifests with mood changes and memory loss. However, this would not account for dietary salt craving and reduced secondary sexual characteristics. (Choice C) A detailed nutritional history may help diagnose anorexia nervosa, which is commonly associated with MDD. However, anorexia nervosa usually requires BMI <18.5 kg/m² and is commonly accompanied by amenorrhea; in addition, salt craving makes PAI more likely. ² (Choice D) Acute HIV infection can present with fatigue and weight loss; however, hepatomegaly and/or splenomegaly is often present as well. In addition, it would not explain salt craving and reduced secondary sexual characteristics. (Choice E) Symptomatic improvement with antidepressant therapy may help confirm suspected MDD; however, this patient's symptoms are more consistent with depressed mood secondary to an underlying medical condition. Once a diagnosis of PAI is confirmed, treatment with corticosteroid replacement therapy is most appropriate. Educational objective: In patients with depressed mood, an underlying medical condition should be considered and may be suggested by findings that are unexplained by psychiatric illness alone. Primary adrenal insufficiency presents with clinical manifestations of deficiency of mineralocorticoids (eg, dietary salt craving), glucocorticoids (eg, fatigue, depressed mood), and androgens (eg, reduced secondary sexual characteristics in women).

A 32-Year-Old Woman Comes to the Office Due to Feeling