Background The 2010 ACR/EULAR classification criteria for rheumatoid arthritis (RA), which include antibodies to citrullinated peptide (ACPA) have good sensitivity and specificity for diagnosing of AR in advanced stages. However, early diagnosis is a challenge not resolved. Recent studies shown the existence of a preclinical stage before development of RA, characterized by arthralgia or a few symtoms that can be detected by special techniques such as High Power Doppler resolution ultrasound (PDRUS) or the presence of these autoantibodies.
Objectives To assess the usefulness of PDRUS and the presence of ACPA in subclinical stage of RA and evaluate the response to treatment with methotrexate in this phase.
Methods We evaluated a cohort of patients ACPA(+) with inflamatory arthralgias who not fulfilled criteria for diagnosis of RA. We performed PDRUS and instaured treatment with methotrexate and low oral dose of prednisone (5 mgr/day) that was subsequently withdrawn.
Laboratory test including rheumathoid factor, CPR, ESR and ACPA; PDRUS attending to power doppler signal (PDS) on a scale from 0 to 3 of bilateral wrists, metacarpophalangeal and interphalangeal; HAQ, VAS and DAS 28 (ultrasound synovitis) were collected at months 0, 1, 3, 6 and 12.
Results Twenty patients ACPA positive with inflammatory arthralgia and PDS were included, 90% women. The mean age was 42.2±12.4 years. The 30% had PDS grade 1, 55% grade 2 and 15% grade 3. Both ESR and CRP remained within normal values.
After 1 month of treatment, the PDS was reduced in 55% of patients. In the patients with grade 1, no PDS was observed; the 2 patients with grade 2 improved to grade 1 and 3 with grade 3 upgraded to grade 2.
After 6 months of treatment, only 6 patients showed PDS (4 of grade 1, and 2 grade 2); and one year later, only 1 patient had PDS signal grade 1. The HAQ and VAS decreased at one year from 2.325±0234 to 0550±0.250 (p<0.05) and from 13.5±75.2±12.8 mm to 32 mm (p<0.05) respectively; and also DAS 28 decreased from 4.2±1.54 to 2.1±0.58 (p<0.05).
Conclusions The patient with inflammatory arthralgia ACPA positive and the presence of ultrasound synovitis without diagnostic criteria for RA, respond satisfactorily to early treatment with methotrexate, achieving clinical remission in a high percentage after the first year.
We can concluded that the presence of ACPA and PDS evaluated by PDRUS are very important tools for the diagnosis of patients with subclinical inflammatory arthralgia related to RA. The presence of synovitis evaluated by PDUS should be considered as a posible diagnostic criteria in very early stages of the disease.
Disclosure of Interest None declared