title: Low oxygen saturation by pulse oximetry may be associated with a low oxygen affinity hemoglobin variant, hemoglobin Titusville.
abstract: The authors describe a 10-year-old Caucasian boy who presented with abnormally low oxygen saturation values on pulse oximetry after a routine tonsillectomy. He was asymptomatic and there was no personal or family history of respiratory, cardiac, or hematologic disorders. Multiple initial investigations were completed without diagnostic yield. Eventually, hemoglobinopathy studies identified the presence of a low oxygen affinity hemoglobin variant, characterized as hemoglobin Titusville. Hemoglobinopathies remain highly prevalent worldwide, with more than 65 low oxygen affinity hemoglobin variants identified to date. Early recognition of abnormal hemoglobin variants in asymptomatic patients may avoid extensive, unnecessary medical investigations.
authors.affiliation: Department of Pediatrics, University of Calgary and Calgary Health Region, Calgary, AB, Canada. rrebecca.deyell@calgaryhealthregion.ca
authors.forename: Rebecca
authors.initials: R
authors.lastname: Deyell
authors.forename: Shannon
authors.initials: S
authors.lastname: Jackson
authors.forename: Sheldon
authors.initials: S
authors.lastname: Spier
authors.forename: Doan
authors.initials: D
authors.lastname: Le
authors.forename: Man-Chiu
authors.initials: MC
authors.lastname: Poon
mesh_terms: D019943:Amino Acid Substitution; D002648:Child; D003937:Diagnosis, Differential; D005914:Globins / Q000235:genetics; D006337:Heart Murmurs; D006453:Hemoglobinopathies / Q000097:blood* / Q000150:complications / Q000175:diagnosis / Q000235:genetics; D006455:Hemoglobins, Abnormal / Q000235:genetics / Q000502:physiology*; D006801:Humans; D000860:Hypoxia / Q000175:diagnosis / Q000209:etiology*; D008297:Male; D020125:Mutation, Missense; D010092:Oximetry; D010108:Oxyhemoglobins / Q000032:analysis; D010375:Pedigree; D010612:Pharyngitis / Q000601:surgery; D017354:Point Mutation; D011183:Postoperative Complications / Q000209:etiology; D012120:Respiration Disorders / Q000097:blood / Q000175:diagnosis; D013290:Streptococcal Infections / Q000601:surgery; D013981:Tic Disorders / Q000150:complications; D014068:Tonsillectomy
chemical_list: D006455:Hemoglobins, Abnormal; D010108:Oxyhemoglobins; C509059:hemoglobin Titusville; D005914:Globins