{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T09:55:31Z","timestamp":1781862931630,"version":"3.54.5"},"reference-count":10,"publisher":"Springer Science and Business Media LLC","license":[{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100002668","name":"Abant Izzet Baysal University","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100002668","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Ir J Med Sci"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Type 1 CYB5R3 deficiency is a rare cause of hereditary methemoglobinemia. Although it is typically diagnosed during childhood, it may also be identified in older adults.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Case<\/jats:title>\n                    <jats:p>A 62-year-old male patient presenting with cyanosis and shortness of breath was diagnosed with Type 1 CYB5R3 deficiency. The diagnosis was supported by the chocolate-brown appearance of arterial blood, a methemoglobin (metHb) level of 17%, hypoxemia inconsistent with pulse oximetry findings, and the identification of a homozygous pathogenic mutation in CYB5R3 on sequence analysis. The patient is currently being followed with supplemental oxygen therapy and vitamin C treatment.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>In patients presenting with cyanosis and hypoxemia, arterial blood gas analysis should be evaluated for methemoglobinemia, as pulse oximetry may provide misleadingly high oxygen saturation readings. Congenital causes must be considered even in elderly patients.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s11845-026-04500-1","type":"journal-article","created":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T09:30:09Z","timestamp":1781861409000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Hereditary methemoglobinemia diagnosed in adulthood: Type 1 cytochrome B5 reductase deficiency"],"prefix":"10.1007","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2450-6378","authenticated-orcid":false,"given":"Emine","family":"Af\u015fin","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muzaffer","family":"\u015eenol","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ay\u015fe","family":"G\u00fcrel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emine","family":"Durak","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,19]]},"reference":[{"key":"4500_CR1","volume-title":"Chapter 51: Methemoglobinemia and Other Dyshemoglobinemias","author":"J Prchal","year":"2021","unstructured":"Prchal J (2021) Chapter 51: Methemoglobinemia and Other Dyshemoglobinemias, 10th edn. McGraw Hill, New York","edition":"10"},{"issue":"6","key":"4500_CR2","doi-asserted-by":"publisher","first-page":"924","DOI":"10.16899\/jcm.946473","volume":"11","author":"D Erg\u00fcn","year":"2021","unstructured":"Erg\u00fcn D, Narin E, Erg\u00fcn R, Kanat F, G\u00f6ksel B (2021) A rare cause of hypoxemia: hereditary methemoglobinemia. J Contemp Med 11(6):924\u2013926","journal-title":"J Contemp Med"},{"issue":"12","key":"4500_CR3","doi-asserted-by":"publisher","first-page":"1666","DOI":"10.1002\/ajh.26340","volume":"96","author":"A Iolascon","year":"2021","unstructured":"Iolascon A, Bianchi P, Andolfo I, Russo R, Barcellini W, Fermo E et al (2021) Recommendations for diagnosis and treatment of methemoglobinemia. 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Molecular basis of recessive congenital methemoglobinemia, types I and II: Exon skipping and three novel missense mutations in the NADH-cytochrome b5 reductase (diaphorase 1) gene. Hum Mutat. 2001 Apr;17(4):348. https:\/\/doi.org\/10.1002\/humu.31","journal-title":"Cureus"},{"key":"4500_CR7","doi-asserted-by":"publisher","first-page":"102","DOI":"10.7759\/cureus.35974","volume":"7","author":"SJ Barker","year":"1991","unstructured":"Aldeeb M, Khalil IA, Yassin MA. Congenital Methemoglobinemia in a 33-Year-Old Patient: A Case Report on a Rare Presentation and a Review of the Literature. Cureus. 2023 Mar 10;15(3):e35974. https:\/\/doi.org\/10.7759\/cureus.35974","journal-title":"J Clin Monit"},{"issue":"4","key":"4500_CR8","doi-asserted-by":"publisher","first-page":"1043","DOI":"10.1053\/j.jvca.2013.02.005","volume":"28","author":"JA Cortazzo","year":"2014","unstructured":"Barker SJ, Le N, Hyatt J (1991) Failure rates of transmission and reflectance pulse oximetry for various sensor sites. J Clin Monit 7:102\u2013103","journal-title":"J Cardiothorac Vasc Anesth"},{"issue":"5","key":"4500_CR9","doi-asserted-by":"publisher","first-page":"685","DOI":"10.1016\/j.jemermed.2017.04.036","volume":"53","author":"Y Cho","year":"2017","unstructured":"Cortazzo JA, Lichtman AD (2014) Methemoglobinemia: a review and recommendations for management. J Cardiothorac Vasc Anesth 28(4):1043\u20137. https:\/\/doi.org\/10.1053\/j.jvca.2013.02.005","journal-title":"J Emerg Med"},{"issue":"5","key":"4500_CR10","doi-asserted-by":"publisher","first-page":"685","DOI":"10.1016\/j.jemermed.2017.04.036","volume":"53","author":"Y Cho","year":"2017","unstructured":"Cho Y, Park SW, Han SK, Kim HB, Yeom SR (2017) A Case of Methemoglobinemia Successfully Treated with Hyperbaric Oxygenation Monotherapy. J Emerg Med 53(5):685\u2013687. https:\/\/doi.org\/10.1016\/j.jemermed.2017.04.036","journal-title":"J Emerg Med"}],"container-title":["Irish Journal of Medical Science (1971 -)"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s11845-026-04500-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s11845-026-04500-1","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s11845-026-04500-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T09:30:13Z","timestamp":1781861413000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s11845-026-04500-1"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,19]]},"references-count":10,"alternative-id":["4500"],"URL":"https:\/\/doi.org\/10.1007\/s11845-026-04500-1","relation":{},"ISSN":["0021-1265","1863-4362"],"issn-type":[{"value":"0021-1265","type":"print"},{"value":"1863-4362","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,19]]},"assertion":[{"value":"11 March 2026","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"9 June 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"19 June 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The requirement for ethical approval was waived from our institution ethics Committee.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval and consent to participate"}},{"value":"The patients provided written informed consent to publication of this report.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors have declared that no competing conflicts of interest exist.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}]}}