The neurophysiological profile of vitamin B12 deficiency

Abstract
Reports of the incidence and severity of physiological abnormalities of vitamin B12 deficiency sharply differ. To resolve these controversies we performed evoked response and nerve conduction studies in 10 males with vitamin B12 deficiency. The minimum criteria for this diagnosis were diminished position and vibration sensation and vitamin B12 levels 12 deficiency: essentially normal BAERs, mildly abnormal VERs and median SERs, and markedly abnormal peroneal SERs. NCV studies are consistent with sensory‐motor axonopathy.