Nutritional infantile vitamin B12 deficiency: pathobiochemical considerations in seven patients

Clinical pattern, mutations and in vitro residual activity in 33 patients with severe 5, 10 methylenetetrahydrofolate reductase (MTHFR) deficiency

“…Although low Met and high tHcy are the biochemical hallmarks of the disease, their concentrations are not correlated with age at onset, genotype, residual enzyme activity or severity/pattern of clinical symptoms, which is consistent with previous reports ( The central muscular hypotonia and acute encephalopathy seen in our cohort are common features in early-onset inborn errors of metabolism. However, the severe feeding problems as observed in this cohort are consistently reported in MTHFR deficiency and other remethylation disorders (Fischer et al 2014) as well as in nutritional vitamin B12 deficiency (Roschitz et al 2005) and seem to be a more specific finding. Thus, when such problems are identified in undiagnosed patients (especially in the presence of microcephaly) they should focus the clinicians' attention towards a disease from this group and prompt the assessment of tHcy.…”

West syndrome due to vitamin B12 deficiency

“…It may be explained with the fact that brain neurons covered with damaged myelin are more sensitive to the stimulating effects of glutamate (4). Generalized tonic clonic and focal seizures related with vitamin B12 deficiency have been described (8). Kumar (4) reported that vitamin B 12 deficiency was involved in the etiology and very good response was obtained with vitamin B 12 treatment in a 26-year old male patient who had behavioral change for the last one year and did not respond to risperidone and carbamazepine treatment which was given for complex partial seizures for the last three weeks.…”

‘Vitamin B12 deficiency and seizures’

“…The seizures in these cases began before treatment with vitamin B 12 and therapy resulted in prompt cessation of seizures 5,6 . However, therapy resistant seizures may occur, 2 although seizures occurring after vitamin B 12 therapy are not often reported. Johnson and Roloff 7 reported a child who began having myoclonic seizures 3 months after discharge.…”

“…Previously, Roschitz et al 2 reported seven infants with VBD due to maternal vegan diet. One of them had focal seizures as the first symptom.…”

“…Reports about epileptic seizures in children with VBD are sparse. Generalized tonic–clonic and focal seizures have been described as VBD‐related seizures 2,5,6 . The seizures in these cases began before treatment with vitamin B 12 and therapy resulted in prompt cessation of seizures 5,6 .…”