A 62-year-old man, who has not seen a physician in 20 years, presents to your...

This is a classic presentation of diabetic peripheral neuropathy: bilateral distal sensory symptoms with preserved motor function and no other systemic findings. The most useful test to confirm this in a previously undiagnosed patient is HbA1c.

Toronto Notes 2023 – Endocrinology, Diabetes Complications:

“Peripheral neuropathy is a common complication of undiagnosed or poorly controlled diabetes. Confirm with HbA1c if diagnosis is not yet established.”

MCCQE1 Objectives – Internal Medicine > Endocrinology:

“Candidates should evaluate for diabetes in patients with peripheral neuropathy and screen appropriately with HbA1c.”

Folate (B) and B12 deficiency may also cause neuropathy but are less likely in the absence of nutritional risk factors. Other choices (A, D, E) are unrelated to this pattern.

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