title: Validation of the immunochromatographic strip for α-thalassemia screening: a multicenter study.
abstract: α(0)-Thalassemia occurs from a deletion of 2 linked α-globin genes and interaction of these defective genes leads to hemoglobin (Hb) Bart's hydrops fetalis, the most severe and lethal thalassemia syndrome. Identification of α(0)-thalassemia carriers is thus essential for the prevention and control program. An immunochromatographic (IC) strip test was developed for rapid screening of α(0)-thalassemia by testing for Hb Bart's in the blood samples using a specific monoclonal antibody against Hb Bart's. To evaluate its sensitivity and specificity, the IC strip test was assessed in a cohort with various thalassemia genotypes from 4 different laboratories in Thailand and Australia. The result showed 97% sensitivity in α-thalassemia carriers with 2 α-globin genes deletion and Hb H disease. This is, in particular, the useful rapid screening test for regions where β-thalassemia and homozygous Hb E are also common. Similar hematologic and Hb data make it impossible to address the concomitant inheritance of α(0)-thalassemia in these samples without polymerase chain reaction (PCR)-based techniques, leading to misdiagnosis of the risk of having Hb Bart's hydrops fetalis. However, α-globin genotyping should be carried out in samples with positive IC strip as positive reactivity was also observed in homozygous α(+)-thalassemia carriers who have 2 trans α-globin gene deletions. These results indicate that in combination with red blood cell indices, the IC strip test could rule out mass populations for further α(0)-thalassemia detection by PCR-based analysis. The Alpha Thal IC strip also has the potential to replace testing for Hb H inclusion bodies, as it appears to be more sensitive, specific, and less labor intensive.
authors.affiliation: Thalassemia Research Centre, Institute of Molecular Biosciences, Mahidol University, Nakhonpathom, Thailand.
authors.forename: Pranee
authors.initials: P
authors.lastname: Winichagoon
authors.affiliation: Thalassemia Research Centre, Institute of Molecular Biosciences, Mahidol University, Nakhonpathom, Thailand.
authors.forename: Pornnapa
authors.initials: P
authors.lastname: Kumpan
authors.affiliation: Department of Hematology, PathWest Laboratory Medicine, Queen Elizabeth II Medical Centre, Nedlands, Perth, Western Australia, Australia.
authors.forename: Paula
authors.initials: P
authors.lastname: Holmes
authors.affiliation: Department of Hematology, PathWest Laboratory Medicine, Queen Elizabeth II Medical Centre, Nedlands, Perth, Western Australia, Australia; School of Pathology and Laboratory Medicine, University of Western Australia, Nedlands, Perth, Western Australia, Australia.
authors.forename: Jill
authors.initials: J
authors.lastname: Finlayson
authors.affiliation: Department of Diagnostic Molecular Genetics, PathWest Laboratory Medicine, Queen Elizabeth II Medical Centre, Nedlands, Perth, Western Australia, Australia.
authors.forename: Christopher
authors.initials: C
authors.lastname: Newbound
authors.affiliation: Douglass Hanly Moir Pathology, Macquarie Park, New South Wales, Australia.
authors.forename: Arnold
authors.initials: A
authors.lastname: Kabral
authors.affiliation: Douglass Hanly Moir Pathology, Macquarie Park, New South Wales, Australia.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Li
authors.affiliation: School of Allied Health Sciences and Public Health, Walailak University, Nakhon Si Thammarat, Thailand.
authors.forename: Manit
authors.initials: M
authors.lastname: Nuinoon
authors.affiliation: Biospecifix, Melbourne, Australia.
authors.forename: Terry
authors.initials: T
authors.lastname: Fawcett
authors.affiliation: Division of Clinical Immunology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Chatchai
authors.initials: C
authors.lastname: Tayapiwatana
authors.affiliation: Division of Clinical Immunology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Watchara
authors.initials: W
authors.lastname: Kasinrerk
authors.affiliation: Thalassemia Research Centre, Institute of Molecular Biosciences, Mahidol University, Nakhonpathom, Thailand. Electronic address: suthat.fuc@mahidol.ac.th.
authors.forename: Suthat
authors.initials: S
authors.lastname: Fucharoen
mesh_terms: D002846:Chromatography, Affinity / Q000295:instrumentation*; D005838:Genotype; D006801:Humans; D017085:alpha-Thalassemia / Q000175:diagnosis* / Q000235:genetics