Background Imaging data indicates that Rheumatoid Arthritis (RA) patients in clinical remission (CR) may present persistent sub-clinical inflammatory activity. Positive Power Doppler Ultrasonography (PDUS) signal in joints is considered to be active inflammation. It has also been seen in RA patients in CR, although the meaning of this data has to be determined. Besides, we do not know how accurate the physical examination is compared to the ultrasonographic examination in patients with low activity. Nor do we know the relationship between both ways to examine joints
Objectives To analyze the correlation between physical and ultrasonographic joint examination and the degree of persistent inflammatory signs in our RA patients with low disease activity (LDA) or in CR.
Methods A validated twelve-joint simplified PDUS assessment of joint inflammation in RA was performed in RA patients with CR or LDA, according to DAS-28 clinical criteria. Clinical and ultrasonographic examinations were independent and blinded between the rheumatologists
Results 30 RA patients with DAS28<3.2 were included. Twenty-four patients were in CR (DAS28<2.6) and 6 had LDA. Mean age was 55.8 yrs, 70% of them were females. 46% of patients were treated with biologic therapy and 76% with DMARDs. Only 16% were taking steroids. A PDUS index of zero was found in 13 patients (43%), all except for three were in remission. PDUS index lower than 4 was found in 23 patients (76%), 4 of them in LDA. Among patients with CR, 41 % had a PDUS Index of zero and 79% had index <4. Patients with PDUS index of 0 had lower DAS28 and SDAI and lesser swollen joints than those with PDUS index higher than 0 (p<0.05). Comparing groups with Doppler index lower or higher than 4, these differences were not found, just a tendency in lower DAS 28 (p=0.09). The agreement, normal versus abnormal, between joint and ultrasound examination in each joint, in the joints in common in both indexes (2nd, 3rd MCPs, wrists, elbows and knees), was higher than 90% except in wrists which was 73% in PDUS and 70% in grey scale index.
Conclusions 1-Ultrasonographic Doppler signal reflects disease activity even in patients with low activity or in remission.
2-If we consider Ultrasonographic remission as Doppler index = zero, only 41% of patients with clinical remission would have ultrasound remission. But considering Ultrasonographic remission as Doppler index below 4, then 79% of patients were in clinical and in Ultrasonographic remission
3-There was high concordance rate between physical and Ultrasonographic examination, joint by joint, in the majority of joints examined.
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Peiteado Lopez D, De Miguel Mendieta E, Balsa Criado A, Ordoñez Cañizares C, Martin Mola E. Validez de índices ecográficos reducidos en la valoración de la artritis reumatoide. XXXV meeting of the Spanish Society of Rheumatology 2009.
Disclosure of Interest None Declared