Interlaboratory comparison of current high‐performance methods for HbA<sub>2</sub>

Paleari, Renata; Gulbis, Béatrice; Cotton, Frédéric; Mosca, Andrea

doi:10.1111/j.1751-553x.2012.01403.x

Cited by 25 publications

(16 citation statements)

References 20 publications

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“…However, quite a few cases may present with borderline levels of HbA 2 , no HbF, and indecisive CBC parameters. Then HbA 2 determination can be a source of errors 24 and quite a few inter-laboratory variations 25 and technical pitfalls 26 may cause misdiagnosis when HbA 2 is considered to be a decisive cut off parameter. These gray area cases must be very carefully examined, especially when they are part of a risk assessment with a partner carrier of a plain β thalassemia mutation.…”

Section: Discussionmentioning

confidence: 99%

Role of Novel and Rare Nucleotide Substitutions of the β-Globin Gene

Vinciguerra

Cannata

Cassarà

et al. 2012

Thalassemia Reports

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Section: Discussionmentioning

confidence: 99%

Role of Novel and Rare Nucleotide Substitutions of the β-Globin Gene

Vinciguerra

Cannata

Cassarà

et al. 2012

Thalassemia Reports

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“…1 Factors such as co-elutions, integration modes, calibrations, different columns, different buffers, different temperatures, different sample quality and concentrations have to be considered. These and other factors contribute to an inevitable variety of artifact that makes the use of normal cutoff intervals very risky when the HbA 2 value alone is used to confirm or exclude a possible b-thalassemia trait.…”

Section: Measuring Artifactsmentioning

confidence: 99%

HbA2 Measurements in β-Thalassemia and in Other Conditions

Ivaldi

Barberio

Harteveld

et al. 2014

Thalassemia Reports

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Quite a few papers have been written on the significance of elevated hemoglobin (Hb) A 2 as a parameter for the diagnosis of b-thalassemia trait, on the cutoff values to be used in diagnostics and on the significance and effects of factors reducing or elevating the expression of HbA 2 and last but not least on the need for reliable measurement methods and precise calibrations with accurate standards. However, little has been published on the causes that elevate or reduce the HbA 2 levels in b-and a-thalassemia and in other conditions. For a better understanding of the value of a precise measurement of this parameter we summarize and elucidate in this review the direct and indirect mechanisms that cause the variations in HbA 2 expression and that influence the value of this parameter in particular conditions. We conclude by explaining the advantages and disadvantages of trusting on a precise measurement in the complete diagnostic contest.

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“…To this regard, data obtained in a large external quality assessment scheme [UK NEQAS (H)] and results from a recent inter-laboratory study showed a significant bias between different routine methods for HbA 2 measurement [6,7] . However, it is rather difficult to evaluate the actual analytical quality of HbA 2 testing since at present there is no reference measurement procedure approved for this analyte and no defined specifications for allowable analytical bias and imprecision have been defined.…”

Section: Introductionmentioning

confidence: 99%

Analytical goals for the determination of HbA2

Mosca¹,

Paleari²,

Wild³

2013

Clinical Chemistry and Laboratory Medicine

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Background: We present a study aimed to define the analytical goals for the determination of hemoglobin A 2 , a minor hemoglobin present in human blood normally accounting from 2.5 % to 3.3 % of total hemoglobin, and typically increased up to 6 % -7 % in subjects carriers of β -thalassemia. Methods: The analytical goals have been derived using two approaches, the first one based on biologic variation, and the second one based on the opinion of experts. Results: The data obtained by studying 17 adult non-carrier healthy subjects, from whom we took blood samples every 2 weeks for 2.0 months, indicated a small intraindividual biologic variation (CV I of 0.7 % ), with respect to a larger between-subject variation (CV G of 7.7 % ). The minimum levels for imprecision, bias and total error derived from the analysis of these data were: 0.5 % , 2.9 % and 4.5 % , respectively. The limits derived from the opinion of experts were based on a questionnaire with three clinical cases, which was circulated among two teams of international experts, and on a discussion about the clinical needs. The average total error derived from such surveys ranged between 7.0 % and 9.5 % . Conclusions:The various methods to derive analytical performance goals gave different limits, thus indicating the need for an increased communication between clinicians and laboratory professionals on this matter.

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Interlaboratory comparison of current high‐performance methods for HbA₂

Abstract: A poor alignment of routine methods for HbA(2) measurement was found. The need of a better standardization of HbA(2) measurement procedures was underlined.

Cited by 25 publications

References 20 publications

Role of Novel and Rare Nucleotide Substitutions of the β-Globin Gene

Role of Novel and Rare Nucleotide Substitutions of the β-Globin Gene

HbA2 Measurements in β-Thalassemia and in Other Conditions

Analytical goals for the determination of HbA2

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Interlaboratory comparison of current high‐performance methods for HbA2

Abstract: A poor alignment of routine methods for HbA(2) measurement was found. The need of a better standardization of HbA(2) measurement procedures was underlined.

Cited by 25 publications

References 20 publications

Role of Novel and Rare Nucleotide Substitutions of the β-Globin Gene

Role of Novel and Rare Nucleotide Substitutions of the β-Globin Gene

HbA2 Measurements in β-Thalassemia and in Other Conditions

Analytical goals for the determination of HbA2

Contact Info

Product

Resources

About

Interlaboratory comparison of current high‐performance methods for HbA₂