TY  - JOUR
A1  - Wojtalewicz, Nathalie
A1  - Vierbaum, Laura
A1  - Schellenberg, Ingo
A1  - Hunfeld, Klaus-Peter
T1  - Evaluation of INSTAND e.V.’s external proficiency testing program for tetanus and diphtheria antitoxin detection: Lessons for assessing levels of immunoprotection
T2  - International Journal of Infectious Diseases
N2  - Objectives: The aim of this study was to evaluate the development and status quo of the quality of high throughput in vitro diagnostic testing for tetanus and diphtheria antitoxin antibody (ATX) concentrations based on external quality assessment (EQA) data.
Methods: We analyzed manufacturer-specific data of 22 EQA surveys—each for the detection of tetanus and diphtheria ATX—to check the diagnostic strength of the corresponding in vitro diagnostic systems.
Results: While the results were mostly well aligned, individual surveys showed widely dispersed ATX concentrations. The medians of manufacturer collectives deviated from the overall median by up to 8.9-fold in the case of diphtheria ATX and by up to 3.5-fold in the case of tetanus ATX. Such a distribution in the results is particularly critical in the cut-off range for immunity and may lead to an incorrect assessment of vaccination status.
Conclusion: These results were surprising as there are International Standards for both ATX; however, the results may be linked to the high ATX concentration of the reference material, which deviates considerably from clinically significant concentrations. To increase the accuracy and diagnostic strength of both assays, we recommend a recalibration of the test systems and verification of their traceability to the International Standards.
KW  - EQA scheme
KW  - Proficiency testing
KW  - Diphtheria
KW  - Tetanus
KW  - Vaccine
KW  - Standardization
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/78147
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-781476
SN  - 1201-9712
VL  - 104
SP  - 85
EP  - 91
PB  - Elsevier
CY  - Amsterdam
ER  -