Brik R, Lorber M, Rivkin M, Nahir A M
B. Shine Department of Rheumatology, Rambam Medical Center, Haifa, Israel.
Clin Exp Rheumatol. 1990 May-Jun;8(3):293-6.
Previous studies have strongly suggested an association between rheumatoid factors (RF's), particularly IgA-RF, and the presence of erosions in rheumatoid arthritis (RA). The present study was aimed at studying this association in seronegative erosive arthritides. Forty-eight patients with seronegative arthritis were evaluated for the presence of IgM- and IgA-RFs using an enzyme linked immunosorbent assay (ELISA). Twenty-nine had seronegative RA and nineteen had psoriatic arthritis (PA). Twelve (41%) seronegative RA patients were found to be seropositive for IgM- or IgA-RF. Only 1 (7%) patient with PSA was positive for IgA-RF alone. Fifteen (51%) of the RA patients and eight (42%) of the PSA patients had erosive disease. A significant correlation between IgA-RF alone and erosive disease was found only in the seronegative RA patient (p less than 0.02). We conclude that in PSA patients there appears to be no need to define isotype specific RFs. On the other hand, our findings indicate that an early detection of IgA-RF can have clinical importance in seronegative rheumatoid arthritis, as it may constitute an indication for the timely institution of disease-modifying drugs in these patients.
以往研究强烈提示类风湿因子（RFs），尤其是IgA-RF，与类风湿关节炎（RA）中的骨侵蚀存在关联。本研究旨在探讨血清阴性侵蚀性关节炎中的这种关联。采用酶联免疫吸附测定（ELISA）对48例血清阴性关节炎患者的IgM-和IgA-RF进行评估。其中29例为血清阴性RA患者，19例为银屑病关节炎（PA）患者。12例（41%）血清阴性RA患者的IgM-或IgA-RF呈血清阳性。仅1例（7%）PA患者单独IgA-RF呈阳性。15例（51%）RA患者和8例（42%）PA患者存在侵蚀性病变。仅在血清阴性RA患者中发现单独IgA-RF与侵蚀性病变之间存在显著相关性（p<0.02）。我们得出结论，在PA患者中似乎无需确定同种型特异性RFs。另一方面，我们的研究结果表明，在血清阴性类风湿关节炎中早期检测IgA-RF可能具有临床重要性，因为这可能是这些患者及时应用改善病情药物的一个指征。
