Longitudinal analysis of ANA in the Systemic Lupus International Collaborating Clinics (SLICC) Inception Cohort.
Ann Rheum Dis
; 81(8): 1143-1150, 2022 08.
Article
em En
| MEDLINE
| ID: mdl-35338033
ABSTRACT
OBJECTIVES:
A perception derived from cross-sectional studies of small systemic lupus erythematosus (SLE) cohorts is that there is a marked discrepancy between antinuclear antibody (ANA) assays, which impacts on clinicians' approach to diagnosis and follow-up. We compared three ANA assays in a longitudinal analysis of a large international incident SLE cohort retested regularly and followed for 5 years.METHODS:
Demographic, clinical and serological data was from 805 SLE patients at enrolment, year 3 and 5. Two HEp-2 indirect immunofluorescence assays (IFA1, IFA2), an ANA ELISA, and SLE-related autoantibodies were performed in one laboratory. Frequencies of positivity, titres or absorbance units (AU), and IFA patterns were compared using McNemar, Wilcoxon and kappa statistics, respectively.RESULTS:
At enrolment, ANA positivity (≥180) was 96.1% by IFA1 (median titre 11280 (IQR 1640-15120)), 98.3% by IFA2 (12560 (IQR 1640-15120)) and 96.6% by ELISA (176.3 AU (IQR 106.4 AU-203.5 AU)). At least one ANA assay was positive for 99.6% of patients at enrolment. At year 5, ANA positivity by IFAs (IFA1 95.2%; IFA2 98.9%) remained high, while there was a decrease in ELISA positivity (91.3%, p<0.001). Overall, there was >91% agreement in ANA positivity at all time points and ≥71% agreement in IFA patterns between IFA1 and IFA2.CONCLUSION:
In recent-onset SLE, three ANA assays demonstrated commutability with a high proportion of positivity and titres or AU. However, over 5 years follow-up, there was modest variation in ANA assay performance. In clinical situations where the SLE diagnosis is being considered, a negative test by either the ELISA or HEp-2 IFA may require reflex testing.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Anticorpos Antinucleares
/
Lúpus Eritematoso Sistêmico
Tipo de estudo:
Diagnostic_studies
/
Observational_studies
/
Prevalence_studies
/
Risk_factors_studies
Limite:
Humans
Idioma:
En
Revista:
Ann Rheum Dis
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Canadá