Clinical features of ACPA-negative and ACPA-positive variants of rheumatoid arthritis

The aim of the study was to study the features of the clinical picture of the disease in patients with ACPA-negative and ACPA-positive variants of rheumatoid arthritis.Materials and methods. The study included patients with a reliable diagnosis of rheumatoid arthritis (RA) according to the criteria of ACR/EULAR 2010. Depending on the values of the ACPA, two groups of patients were recruited: ACPA-positive and ACPA-negative, comparable in gender, age, duration of the disease and therapy. The nature of the onset and course of the disease, the activity of RA were evaluated (according to the DAS28, SDAI, CDAI indices).Results and discussion. The study included 79 patients with ACPA-negative variant of RA and 79 with ACPA-positive. Age of patients (Me [IR], in years) with the ACPA(–) variant was 52 [39; 62], with the ACPA(+) – 54 [42; 62], the duration of the disease (in months) is 59 [23; 122] and 48 [17; 84] respectively. In ACPA(+) patients, higher disease activity was determined by the indices DAS28-CRP, DAS28-ESR, SDAI, CDAI, values of C-reactive protein and erythrocyte sedimentation rate, a greater number of painful and swollen joints (p<0.05). According to the localization of the involved joints, arthritis of the proximal interphalangeal, metacarpal, wrist and shoulder joints was more often determined in ACPA(+) patients. Systemic manifestations of RA at the time of examination and in the anamnesis were statistically significantly more common in ACPA(+) (32.9%) than in ACPA(–) (17.7%). Of the systemic manifestations, rheumatoid nodules were more common in ACPA(+) patients, a tendency to a higher frequency of neuropathy, scleritis and episcleritis was revealed in ACPA(–) patients.Conclusion. In patients with ACPA(–) subtype, clinical signs of joint damage and the inflammatory component are less pronounced compared to ACPA(+). However, the mixed picture of manifestation, the less “bright” course of the disease, the absence of characteristic immunological biomarkers necessitate long-term and careful monitoring of this group of patients. At the same time, the subjective severity of the disease and dysfunction due to ankylosing joints do not differ from the ACPA(+) variant of RA.