Send to

Choose Destination
See comment in PubMed Commons below
Neuropediatrics. 2001 Feb;32(1):14-22.

Cobalamin (Cbl) C/D deficiency: clinical, neurophysiological and neuroradiologic findings in 14 cases.

Author information

III Division of Paediatrics, G. Gaslini Institute, Genova, Italy.


The early onset type of cobalamin (Cbl) C/D deficiency is characterised by feeding difficulties, failure to thrive, hypotonia, seizures, microcephaly and developmental delay. It has an unfavourable outcome, often with early death and significant neurological impairment in survivors. While clinical and biochemical features of Cbl C/D deficiency are well known, only a few isolated case reports are available concerning neurophysiological and neuroimaging findings. We carried out clinical, biochemical, neurophysiological and neuroradiologic investigations in 14 cases with early-onset of the Cbl CID defect. Mental retardation was identified in most of the cases. A variable degree of supratentorial white matter atrophy was detected in 11 cases by MR imaging and tetraventricular hydrocephalus was present in the remaining 3 patients. Waking EEG showed a clear prevalence of epileptiform abnormalities, possibly related to the high incidence of seizures in these cases. Increased latency of evoked responses and/or prolongation of central conduction time were the most significant neurophysiological abnormalities. The selective white matter involvement, shown both by neuroradiologic and neurophysiological studies, seems to be the most consistent finding of Cbl C/D deficiency and may be related to a reduced supply of methyl groups, possibly caused by the dysfunction in the methyl-transfer pathway.

[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Georg Thieme Verlag Stuttgart, New York
    Loading ...
    Support Center