title: Incidence of hemoglobinopathies and thalassemias in Northern Alberta. Establishment of reference intervals for HbF and HbA2.
abstract: OBJECTIVE
  The aims of this study were to identify the incidence of hemoglobinopathies and thalassemias in Northern Alberta and calculate the reference intervals (RI) for hemoglobin (Hb) HbF and HbA2.
  
  
  METHODS
  A retrospective ad-hoc analysis of the structural Hb variants and thalassemias identified on patients who had a hemoglobinopathy/thalassemia investigation performed between February 1 to December 31, 2013. Results were extracted from the Laboratory Information System. Statistical analysis was performed using MedCalc® version 11.4.2.0 for Windows software.
  
  
  RESULTS
  6616 hemoglobinopathy/thalassemia investigations and HbS screens were physician requested and 602 Hb variants were fortuitously found during HbA1c analysis. 3438 were interpreted as "normal" and 532 were classified as iron deficient. 3306 individuals, with age ranging from 3 to 92 years were included in the RI calculation. HbA2 RI was 2.3% to 3.4% and HbF 0.0% to 1.8%. 524 and 423 α and β thalassemia traits respectively were identified. Additionally ten δβ thalassemia traits and twelve cases of HbH disease were identified. Regarding hemoglobinopathies, 7% were classified as α-chain variants and 93% as β-chain variants with HbS (46%), HbE (16%), HbD Punjab (8%) and HbC (7%) traits being the most prevalent. We also documented 20 homozygous hemoglobinopathies and 36 compound/double heterozygous hemoglobinopathies.
  
  
  CONCLUSIONS
  A wide diversity of hemoglobinopathies is found in the Northern Alberta population, 80% of the hemoglobinopathies were found as a reflex to HbA1c testing. Reference intervals for HbF and HbA2 were established.
authors: DynaLIFE(DX) Diagnostic Laboratory Services, Edmonton, Alberta, Canada; Dept. Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada. Electronic address: karina.capote@dynalifedx.com.
authors: Karina
authors: K
authors: Rodriguez-Capote
authors: DynaLIFE(DX) Diagnostic Laboratory Services, Edmonton, Alberta, Canada; Dept. Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada.
authors: Trefor N
authors: TN
authors: Higgins
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000416:Alberta / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D005319:Fetal Hemoglobin / Q000378:metabolism*; D006443:Hemoglobin A2 / Q000378:metabolism*; D006453:Hemoglobinopathies / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012015:Reference Standards; D012189:Retrospective Studies; D013789:Thalassemia / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D006443:Hemoglobin A2; D005319:Fetal Hemoglobin
keywords: HbA(2) reference interval; HbF reference interval; Hemoglobin A(2); Hemoglobin analysis; Hemoglobinopathy screening; α-Thalassemia; β-Thalassemia