%0 Case Reports
%T Transcobalamin deficiency - a rare genetic defect in transportation of cobalamin; case report.
%A Iqbal N
%A Meghani MA
%A Khalid W
%A Ansari AH
%A Ansari MUH
%A Ansari SH
%J Ann Hematol
%V 103
%N 8
%D 2024 Aug 8
%M 38976007
%F 4.03
%R 10.1007/s00277-024-05878-7
%X <B>BACKGROUND: </B>Vitamin B12 is primarily transported from plasma to cells by Transcobalamin. Deficiency of Transcobalamin is a rare autosomal recessive disorder that results in unavailability of cobalamin in cells and accumulation of homocysteine and methylmalonic acid.<BR><B>METHODS: </B>We report a case of a 2-year-old male child with persistent pancytopenia, recurrent infections, and megaloblastic anemia. Next-generation sequencing identified a novel variant in exon 8 of TCN2 gene. Substantial improvement has been observed following administration of high doses of parenteral methylcobalamin.<BR><B>CONCLUSIONS: </B>In patients with unresolved pancytopenia and megaloblastic anemia, Transcobalamin deficiency should be investigated and treated promptly to prevent any irreversible and harmful outcome.