Semiquantitative interpretation of anticardiolipin and antiß2glycoprotein I antibodies measured with various analytical platforms: Communication from the ISTH SSC Subcommittee on Lupus Anticoagulant/Antiphospholipid Antibodies.
J Thromb Haemost
; 20(2): 508-524, 2022 02.
Article
em En
| MEDLINE
| ID: mdl-34758192
ABSTRACT
BACKGROUND:
Antiß2glycoprotein I (aß2GPI) and anticardiolipin (aCL) IgG/IgM show differences in positive/negative agreement and titers between solid phase platforms. Method-specific semiquantitative categorization of titers could improve and harmonize the interpretation across platforms.AIM:
To evaluate the traditional 40/80-unit thresholds used for aCL and aß2GPI for categorization into moderate/high positivity with different analytical systems, and to compare with alternative thresholds. MATERIAL ANDMETHODS:
aCL and aß2GPI thresholds were calculated for two automated systems (chemiluminescent immunoassay [CLIA] and multiplex flow immunoassay [MFI]) by receiver operating characteristic curve analysis on 1108 patient samples, including patients with and without antiphospholipid syndrome (APS), and confirmed on a second population (n = 279). Alternatively, regression analysis on diluted standard material was applied to identify thresholds. Thresholds were compared to 40/80 threshold measured by an enzyme-linked immunosorbent assay (ELISA). Additionally, likelihood ratios (LR) were calculated.RESULTS:
Threshold levels of 40/80 units show poor agreement between ELISA and automated platforms for classification into low/moderate/high positivity, especially for aCL/aß2GPI IgG. Agreement for semiquantitative interpretation of antiphospholipid antibodies (aPL) IgG between ELISA and CLIA/MFI improves with alternative thresholds. LR for aPL IgG increase for thrombotic and obstetric APS based on 40/80 thresholds for ELISA and adapted thresholds for the other systems, but not for IgM.CONCLUSION:
Use of 40/80 units as medium/high thresholds is acceptable for aCL/aß2GPI IgG ELISA, but not for CLIA and MFI. Alternative semiquantitative thresholds for non-ELISA platforms can be determined by a clinical approach or by using monoclonal antibodies. Semiquantitative reporting of aPL IgM has less impact on increasing probability for APS.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Inibidor de Coagulação do Lúpus
/
Anticorpos Anticardiolipina
Tipo de estudo:
Prognostic_studies
Limite:
Female
/
Humans
/
Pregnancy
Idioma:
En
Revista:
J Thromb Haemost
Assunto da revista:
HEMATOLOGIA
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Bélgica