Transcobalamin deficiency: vitamin B12 deficiency with normal serum B12 levels.
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ABSTRACT:
SUBMITTER: Khera S
PROVIDER: S-EPMC6827761 | biostudies-literature | 2019 Oct
REPOSITORIES: biostudies-literature
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Transcobalamin deficiency: vitamin B<sub>12</sub> deficiency with normal serum B<sub>12</sub> levels.
Khera Sanjeev S Pramanik Suman Kumar SK Patnaik Saroj Kumar SK
BMJ case reports 20191030 10
Transcobalamin (TC) deficiency is a rare autosomal recessive inborn error of cobalamin transport which clinically manifests in early infancy. We describe a child with TC deficiency who presented with classical clinical and lab stigmata of inborn error of vitamin B<sub>12</sub> metabolism except normal serum B<sub>12</sub> levels. He was started on empirical parenteral cobalamin supplements at 2 months of age; however, the definitive diagnosis could only be established at 6 years of age when a ge ...[more]
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