Brennan et al developed a simple algorithm to identify patients with early rheumatoid arthritis (RA) at risk for developing radiographical erosions. The authors are from the University of Manchester and St. Michael's Hospital (Norfolk) in England.
Parameters:
(1) rheumatoid factor (RF) titer
(2) duration of disease from onset of symptoms to first examination
(3) involvement of large joints
|
Parameter |
Finding |
Score |
|
rheumatoid factor titer |
>= 1:80 |
1 |
|
|
< 1:80 |
0 |
|
duration of disease |
>= 3 months |
1 |
|
|
< 3 months |
0 |
|
number of large joints involved |
>= 2 |
1 |
|
|
0 or 1 |
0 |
|
Score for RF titer |
Score for Disease Duration |
Score for Large Joints |
Pattern |
|
0 |
0 |
0 |
1 |
|
0 |
1 |
0 |
2 |
|
0 |
0 |
1 |
3 |
|
1 |
0 |
0 |
4 |
|
0 |
1 |
1 |
5 |
|
1 |
1 |
0 |
6 |
|
1 |
0 |
1 |
7 |
|
1 |
1 |
1 |
8 |
|
Pattern |
Probability Erosions |
|
1 |
13% |
|
2 |
26% |
|
3 |
37% |
|
4 |
46% |
|
5 |
59% |
|
6 |
67% |
|
7 |
77% |
|
8 |
89% |
Performance:
• In a validation set the positive predictive value was 72%, the negative predictive value was 82% and the accuracy 79%.
Purpose: To predict the risk of radiological joint erosions in a patient with early rheumatoid arthritis using the algorithm of Brennan et al.
Specialty: Immunology/Rheumatology
Objective: risk factors, imaging studies
ICD-10: M05, M06,
