The updated ESPGHAN guidance on coeliac disease recommends the use of common multiples of the upper limit of normal (ULN) for IgA tissue transglutaminase antibodies (TG2) when deciding which diagnostic pathway to follow. The current lack of standardisation between assays makes it difficult to harmonise results between centres as different performance characteristics are observed with each assay. This variability is shown in data from external quality assessment distributions. As a result, the updated guidance is too generalised for use with all the commercial TG2 kits and is therefore not translatable for use in all centres.
*Department of Immunology, UK NEQAS for Immunology, Immunochemistry & Allergy, Sheffield, UK
†STHFT, Sheffield, UK.
Address correspondence and reprint requests to William Egner, Department of Immunology & Protein Reference Unit, Northern General Hospital, Herries Road, Sheffield S5 7AU, UK (e-mail: email@example.com).
Received 23 March, 2012
Accepted 18 June, 2012
The raw data utilised in Appendix II of the guideline was provided by the UK NEQAS Immunology, Immunochemistry and Allergy Unit, of which W.E. is director and D.P. is deputy director. The other authors report no conflicts of interest. UK NEQAS was not formally asked to contribute or review the analysis, graphical presentation, and conclusions and was not formally part of the guideline development process.