A 45-year-old woman with type 1 diabetes presents with numbness, tingling in her feet, and a wide-based gait. She has macrocytic anemia (Hb 8.5 g/dL, MCV 118 fL) and hypersegmented neutrophils on peripheral smear. Vitamin B12 level is low. Which neurological finding is most characteristic of this deficiency?
- A Loss of pain and temperature sensation in a glove-and-stocking pattern
- B Foot drop and wrist drop
- C Loss of vibration sense and proprioception with positive Romberg sign ✓
- D Charcot joints with painless destruction
Correct answer: C. Loss of vibration sense and proprioception with positive Romberg sign
Explanation
Vitamin C12 deficiency causes subacute combined degeneration of the dorsal columns, producing loss of vibration and position sense, sensory ataxia, and positive Romberg sign. Pain and temperature loss is more typical of peripheral neuropathy from diabetes. Foot and wrist drop occur in lead poisoning. Charcot joints occur in tertiary syphilis (tabes dorsalis) or diabetes.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.