Background There is a short window of opportunity for early diagnosis and treatment of rheumatoid arthritis, that may be crucial for reaching remission and a low rate of radiographic progression. High resolution power doppler ultrasonography (PDUS) is helpful in early detection of synovitis and allows an accurate classification of patients with joint inflammation.
Objectives To establish wether the presence of basal power doppler signal in patients with very early arthritis may be helpful in order to establish the risk of final diagnosis of rheumatoid arthritis according ACR criteria 1987 at a year of follow up.
Methods We studied the presence of ultrasonographic Power Doppler (PD) signal on 28 joints (shoulders, elbows, wrists, MCPs, knees) and 44 joints (28 joints and in addition hips, Tarsus, ankles and MTPs), with a mid-range equipment GE L5, in 40 patients with suspected early arthritis The patients were included with at least one of the following inclusion criteria: a) Swelling in 2 or more joints b) pain in MCPs, MTPs and/or the wrists c) morning stiffness of more than 30 minutes with <12 weeks of duration of the symptoms. Presence or not of basal high acute phase reactants and basal erosions (score ≥2 in at least one joint by modified Sharp method) for each patient were registered (37 patients with completed hands and feet radiology available). Presence of RF and/or ACPA positive were recorded as well. At one year follow-up was established whether patients met criteria for RA according1987 ACR or not. Statistical study: Chi-square, Fisher exact test, p univariant and Odds Ratio calculation.
Results The presence of basal power doppler signal in ≥1 joints of 44 (PD44) in baseline visit shows statistically significant association to RA diagnosis at 12 months by ACR 1987 classification criteria, p=0.008, OR=10,72 (1,76–65,24) but the presence of at least one joint with power doppler signal of 28 joints (PD28) did not (p=0.246). FR/ACPA were positive in only 20% and 15% of patients respectively, and were not associated to RA final diagnosis (p=0.236, p=0.152). Presence of basal radiographic erosions were associated to RA, p<0.0005 and OR 28,28 (3,05–261,87), as well as high CRP p=0.045 OR 4,63 (1,62–13,25) and ESR p=0.046, OR 4.5 (1.08–18,69). 17/17 (100%) of patientes with PD44 basal and radiographic erosions had final diagnosis of RA at 12 months.
Conclusions The presence of at least one joint with power doppler signal of 44 joints (PD44) on baseline visit may help to predict the RA diagnosis at 12 months of follow up according to criteria ACR 1987, in patients with very early RA. Presence of positive acute phase reactants and radiographic basal erosions increased the risk of RA as well. Moreover 100% of patients with PD44 in addition to radiographic basal erosions developed RA at 12 months.
Disclosure of Interest None declared