You see a 52-year-old markedly obese man in clinic who complains of arthritic pain in the knees, but otherwise reports no significant health problems. On physical exam you notice a darkening of his skin along the back of his neck, at the folds of his axillary skin, and faintly in the groin area and behind his knees. He states that he has had these darker areas for 'quite a long time'. What laboratory test would be most helpful in confirming your suspicions of his metabolic disorder?
A) Serum blood glucose
B) Thyroid stimulating hormone (TSH)
C) Parathyroid hormone (PTH)
D) Uric acid
E) Urine vanillylmandelic acid (VMA)

Question

Quizplus · Accepted Answer

The darkening of the skin in areas such as the back of the neck and axillary folds is indicative of acanthosis nigricans, which is commonly associated with insulin resistance and type 2 diabetes mellitus. Therefore, a serum blood glucose test would be the most helpful in confirming suspicions of a metabolic disorder related to insulin resistance or diabetes.

You See a 52-Year-Old Markedly Obese Man in Clinic Who