Rapid Review: Acanthosis Nigricans

Acanthosis Nigricans

• Patient will be obese or diabetic
• PE will show thickened, velvety, darkly pigmented plaques on the neck or axillae
• Comments: Screen for diabetes in those not yet diagnosed

Sample question: A 19-year-old woman presents to her primary care provider’s office for a rash on the back of her neck that has grown and gotten darker over the past year. The woman has a past medical history asthma. Her pulse is 66 beats/min, respiratory rate is 18 breaths/min, blood pressure is 132/87 mm Hg, and her body mass index is 29. On exam, there is a horizontal, dark, velvety plaque on her posterior neck. Which of the following diagnostic studies is most appropriate?