MCQ 33 Vitamin B12 deficiency can give rise to all of the following except:

A.Myelopathy
B.Optic atrophy
C.Peripheral neuropathy
D.Myopathy

The correct answer is D.Myopathy


Note: Vitamin B12 Deficiency causes damage to the spinal cord, peripheral nerves and brain.

Site of involvement	Symptoms
Myelopathy (involvement of the posterior and lateral tracts)	-Parasthesias in the hands and feet -Early loss of vibration and position sensation-Progressive ataxic weakness
Peripheral neuropathy	-Loss of deep tendon reflexes
Optic atrophy	-Loss of vision

®Optic atrophy and irritability and other mental changes may be prominent in advanced cases and on occasion are the presenting symptoms (megaloblastic adness). ® The diagnosis is confirmed by the finding of a low serum B12 concentration, elevated levels of homocysteine (homocysteinemia), methylmalonyluria, and a positive Schilling test.