Effects of rheumatoid factor isotypes on disease activity and severity in patients with rheumatoid arthritis: a comparative study

Abstract

The value of rheumatoid factor (RF) isotypes for assessing rheumatoid arthritis (RA) remains debatable. In this study, we have examined the relationships between RF isotypes and disease activity and severity in RA patients. Sixty-two patients with RA, 48 women and 14 men, were studied. RF was measured by nephelometry (RF-N) and IgG-, IgA-, and IgM-RF isotypes were measured using enzyme-linked immunosorbent assay. Serum C-reactive protein and erythrocyte sedimentation rate were also determined. The patients were classified according to disease activity, joint damage, functional status, and presence of pulmonary involvement, rheumatoid nodule, and secondary Sjögren's syndrome. Although the patients with active disease had significantly higher IgA-RF and IgM-RF levels compared to inactive patients, IgA-RF and IgM-RF were not found to be independently associated with disease activity in multivariate analysis. In patients with severe joint damage, IgA-RF and RF-N were significantly higher than those of the other patients. Multiple regression analysis showed that IgA-RF was the unique variable independently associated to severe joint damage. The patients with class III and IV functional index had significantly higher IgM-RF, IgA-RF, and RF-N levels compared to the patients with class I and II functional index; however, RFs were not significantly associated with functional status in multivariate analysis. IgA-RF and IgM-RF were significantly associated with pulmonary involvement and rheumatoid nodule, respectively. No significant associations were found between RF isotypes and secondary Sjögren's syndrome. Our results suggest that the clinical usefulness of IgA and IgM isotypes is better than RF-N. Elevated IgA-RF may be a marker of erosive disease. The usefulness of RF isotypes for monitoring disease activity or functional status appears to be limited.

Association of PTPN22 1858C→T polymorphism, HLA-DRB1 shared epitope and autoantibodies with rheumatoid arthritis

“…On the other hand, the combination of positive antibodies or SE with T allele variant increases the risk of susceptibility to RA and development of erosive disease more than the sum of each separate one. The highest risk was associated with anti-CCP and RF IgG which support previous studies that showed the association of anti-CCP and RF with bone erosion in RA [37,38]. The observed interaction indicates the existence of a disease mechanism that requires the simultaneous presence of the PTPN22 1858C→T polymorphism and HLA-DRB1 SE alleles and autoantibodies.…”

Rheumatoid Arthritis in Rheumatological Care of Russia: The Severity of the Disease in a Russian Patient Population: A Cross-Sectional Epidemiological Study (Raiser)

“…В характеристике «тяжести» РА большинство авторов ставят на первое место выраженность и скорость развития деструктивного процесса в суставах [6][7][8][9], а так-же связанный с ними функциональный статус пациента [10][11][12], другие учитывают также наличие и выраженность внесуставных проявлений РА [13,14]. При этом сущест-венное место в формировании тяжести РА отводится гене-тическим, серологическим и внешнесредовым факторам (аллели системы HLA, shared epitope, изотипы РФ, антите-ла к цитруллинированному пептиду, курение и др.…”

Infliximab (Remicade): Possibilities in the Treatment of Rheumatoid Arthritis

“…Наличие прогностически неблагоприятных призна-ков: активный РА с большим числом болезненных и припух-ших суставов; эрозии на ранней стадии болезни; повышение уровня РФ и/или антител к циклическому цитруллиниро-ванному пептиду (АЦЦП) [19,20], СОЭ и/или СРБ [21,22].…”