{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T19:08:37Z","timestamp":1787166517687,"version":"build-2736575974"},"reference-count":11,"publisher":"BMJ","issue":"10","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2019,10,15]]},"published-print":{"date-parts":[[2019,10]]},"abstract":"<jats:p>\n                    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\n                    <jats:sub>12<\/jats:sub>\n                    metabolism except normal serum B\n                    <jats:sub>12<\/jats:sub>\n                    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 genetic evaluation revealed homozygous nonsense variation in exon 8 of the TCN2 gene (chr22:g.31019043C&gt;T).\n                  <\/jats:p>","DOI":"10.1136\/bcr-2019-232319","type":"journal-article","created":{"date-parts":[[2019,10,30]],"date-time":"2019-10-30T10:25:25Z","timestamp":1572431125000},"page":"e232319","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":9,"title":["Transcobalamin deficiency: vitamin B\n                    <sub>12<\/sub>\n                    deficiency with normal serum B\n                    <sub>12<\/sub>\n                    levels"],"prefix":"10.1136","volume":"12","author":[{"given":"Sanjeev","family":"Khera","sequence":"first","affiliation":[{"name":"Pediatrics, Army Hospital Research and Referral, New Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suman Kumar","family":"Pramanik","sequence":"additional","affiliation":[{"name":"Hematology, Army Hospital Research and Referral, New Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saroj Kumar","family":"Patnaik","sequence":"additional","affiliation":[{"name":"Pediatrics, Army Hospital Research and Referral, New Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2019,10,30]]},"reference":[{"key":"2025082623002227000_12.10.e232319.1","doi-asserted-by":"crossref","first-page":"2711","DOI":"10.1182\/blood.V85.10.2711.bloodjournal85102711","article-title":"The cloning and characterization of the human transcobalamin II 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Deficiency","volume":"3","author":"Wolffenbuttel","year":"2019","journal-title":"Mayo Clin Proc Innov Qual Outcomes"},{"key":"2025082623002227000_12.10.e232319.6","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2141.1992.tb06410.x"},{"key":"2025082623002227000_12.10.e232319.7","doi-asserted-by":"crossref","first-page":"461","DOI":"10.1007\/s10545-013-9664-5","article-title":"Update on transcobalamin deficiency: clinical presentation, treatment and outcome","volume":"37","author":"Trakadis","year":"2014","journal-title":"J Inherit Metab Dis"},{"key":"2025082623002227000_12.10.e232319.8","doi-asserted-by":"publisher","DOI":"10.1038\/nrg3493"},{"key":"2025082623002227000_12.10.e232319.9","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1007\/s10545-008-0864-3","article-title":"Transcobalamin (TC) deficiency\u2014potential cause of bone marrow failure in childhood","volume":"31","author":"Prasad","year":"2008","journal-title":"J Inherit Metab 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Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2019-232319","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,27]],"date-time":"2025-08-27T06:00:32Z","timestamp":1756274432000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2019-232319"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,10]]},"references-count":11,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2019,10,30]]},"published-print":{"date-parts":[[2019,10]]}},"alternative-id":["10.1136\/bcr-2019-232319"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2019-232319","relation":{},"ISSN":["1757-790X"],"issn-type":[{"value":"1757-790X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,10]]}}}