.One of the diseases that is usually considered in differential diagnosis of MS is vitamin B12 deficiency.Differential diagnosis howere maybe difficult because neurological and hematological disorder may develop independently and with various intensity,pernicious anemia may respond to steroid therapy,MRI finding in vitamin B12 deficiency maybe similar to that in MS and multiple sclerosis may coexist with low vitamin B12 level
heterogeneous manifestations of MS an incorrect diagnosis is not uncommon.One of them is usually considered in DD of MS is Cobalamin deficiency
A 43 years old male was referred our neurologic clinic with primary diagnosis of multiple sclerosis.The patient was admitted because of subacute and progressive weakness and parasthesia of lower limbs.He had hypothyroidism in medical story ,but had no remarkable family and social history.No obvious abnormalities were detected in general examination.The neurological symptoms of gait disturbances and paresthesia.In neurological examination he revealed spasticity in both lower limbs ,brisk deep tendon reflexes and symmetric bilateral extensor plantar response and sensory examination showed abnormalities in vibration and position sense.Sensory level was not detected.The patient had marked sensory ataxia.The laboratory tests revealed RBC count:2/19 million/dl ,Hb:9/7,MCV:127,MCH:44,ESR:30,Retic:0/8.Furthermore peripheral blood smear showed macro-ovalocytes and hypersegmeted neutrophils.B12 level:30.Brain MRI was normal,cervical MRI showed long T2 hyper signal lesion at posterior of cord from C2-C7 .
Cobalamin deficiency Pathology is demyelination involving the lower cervical and upper thoracic regions,it eventually involves the entire dorsal columns symmetrically.That is manifest with neurological features .sing of dorsal column involvement .lateral column involvement and spinotalamic tracts .The diagnosis of B12 deficiency is made by a low serum B12 level or elevated levels of metabolites .MRI findings ;vertical segment can be seen at the posterior aspect of spinal cord. On axial images,bilateral paired areas of T2 hyperintensey are seen as inverted V in dorsal columns.Contrast enhancement areas of a normal signal intensity on T2-weighted image in the cerebral white matter.the most important differential diagnosis of Vitamin B12 deficiency is multiple sclerosis.MS plaques in dorsal column are not bilaterally symmetrical and longitudinal exent is less than two vertebral bodies and may show contrast enhancement,finally are seen younger population
Differential diagnosis howere maybe difficult because neurological and hematological disorder may develop independently and with various intensity,pernicious anemia may respond to steroid therapy,MRI finding in vitamin B12 deficiency maybe similar to that in MS and multiple sclerosis may coexist with low vitamin B12 level.