Van der Helm-van Mil et al developed a prediction rule for evaluating a patient with recent onset of undifferentiated arthritis. This can help identify a patient who may progress to rheumatoid arthritis or similar condition. The authors are from Leiden University in The Netherlands.
Parameter:
(1) age in years)
(2) gender
(3) involvement of small joints in hands and/or feet
(4) symmetry of involvement
(5) distribution of involved joints in the limbs
(6) morning stiffness as rated on a 100 mm visual analogue scale (VAS)
(7) number of tender joints (out of 44)
(8) number of swollen joints (out of 44)
(9) C-reactive protein (CRP) in mg/L
(10) rheumatoid factor
(11) anti-CCP antibody
|
Parameter |
Finding |
Points |
|
gender of the patient |
male |
0 |
|
|
female |
1 |
|
small joints of hands/feet |
absent |
0 |
|
|
present |
0.5 |
|
involvement |
asymmetrical |
0 |
|
|
symmetrical |
0.5 |
|
distribution |
not in limbs |
0 |
|
|
lower extremities only |
0 |
|
|
upper extremities |
1 |
|
|
upper and lower extremities |
1.5 |
|
morning stiffness |
<= 25 mm |
0 |
|
|
26 - 90 mm |
1 |
|
|
91 - 100 |
2 |
|
tender joint count |
0 - 3 |
0 |
|
|
4 - 10 |
0.5 |
|
|
>= 11 |
1 |
|
swollen joint count |
0 - 3 |
0 |
|
|
4 - 10 |
0.5 |
|
|
>= 11 |
1 |
|
C-reactive protein |
< 5 mg/L |
0 |
|
|
5 - 50 mg/L |
0.5 |
|
|
>= 51 mg/L |
1.5 |
|
rheumatoid factor |
absent |
0 |
|
|
present |
1 |
|
anti-CCP antibodies |
absent |
0 |
|
|
present |
2 |
where:
• The point assignment for small joints, symmetry and limb distribution seems to be the only way to get the maximum of 14+ points.
total score =
= (0.02 * (age in years)) + SUM(points for the other parameters)
Interpretation:
• minimum score: 0
• maximum score: 14-15
• The higher the score the greater the probability of the patient progressing to rheumatoid arthritis.
|
Total Score |
Probability of RA |
|
0 - 3 |
0% |
|
4 |
7% |
|
5 |
15% |
|
6 |
26% |
|
7 |
51% |
|
8 |
67% |
|
9 |
86% |
|
10 |
92% (from Fig 2), 77% (Table 3) |
|
>= 11 |
100% |
from Table 3, page 437
Performance:
• The area under the ROC curve is around 0.89
Purpose: To evaluate a patient with the recent onset of undifferentiated arthritis using the prediction rule of van der Helm-van Mil et al.
Specialty: Immunology/Rheumatology, Surgery, orthopedic, Infectious Diseases
Objective: clinical diagnosis, including family history for genetics, laboratory tests, response to therapy
ICD-10: M05, M06,
