Spondyloarthritis & psoriatic arthritis
Anti-CD74 IgA antibodies show diagnostic potential for axial spondyloarthritis but are not associated with microscopic gut inflammation
Authors' conclusion
Serum anti-CD74 IgA is a potentially useful diagnostic biomarker for axSpA. However, antibody levels do not correlate with any phenotypical feature, including microscopic gut inflammation, suggesting this to be a disease-specific rather than an inflammatory marker.
Study context
- Population
- Axial SpA (axSpA) patients fulfilling the 2009 ASAS classification criteria, with fibromyalgia (FM) and RA patients as controls; newly diagnosed axSpA patients underwent ileocolonoscopy
- Participants
- 281 / 100 / 34
- Comparison
- Serum anti-CD74 IgA in axSpA vs FM and RA
- axSpAn = 281
- FMn = 100reference
- RAn = 34reference
- Outcome
- Serum anti-CD74 IgA levels and diagnostic performance for axSpA; association with gut inflammation
Methodological detailscase-control, ELISA, ROC analysis
- Case-control
- ELISA
- ROC analysis
Performance
As reported in the abstract
Anti-CD74 IgA level
| Test or model | Value | AUC (axSpA vs FM) | Sensitivity | Specificity | Cut-off |
|---|---|---|---|---|---|
| axSpA | mean 18.8 (SD 12.4) U/ml | 0.70 | 60% | 87% | 15 U/ml |
| FM | mean 10.9 (SD 5.0) U/ml | ||||
| RA | mean 13.7 (SD 9.6) U/ml |
Value
axSpAmean 18.8 (SD 12.4) U/ml
FMmean 10.9 (SD 5.0) U/ml
RAmean 13.7 (SD 9.6) U/ml
AUC (axSpA vs FM)
axSpA0.70
FM— not stated in the abstract
RA— not stated in the abstract
Sensitivity
axSpA60%
FM— not stated in the abstract
RA— not stated in the abstract
Specificity
axSpA87%
FM— not stated in the abstract
RA— not stated in the abstract
Cut-off
axSpA15 U/ml
FM— not stated in the abstract
RA— not stated in the abstract
- axSpA vs FM: P < 0.001
- axSpA vs RA: P = 0.02
Further findings
- Anti-CD74 IgA by microscopic gut inflammation in axSpA — AUC for gut inflammation · axSpA with gut inflammation (n = 40) vs axSpA without gut inflammation (n = 69) · not significantly different
- 0.51 · P = 0.83
Association with sacroiliac MRI bone marrow oedema, CRP, NSAID or biological treatment
- Anti-CD74 IgA levels not associated with any of these features
Original publication
Anti-CD74 IgA antibodies show diagnostic potential for axial spondyloarthritis but are not associated with microscopic gut inflammation. Rheumatology (Oxford). Published 4 July 2022. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →