Laboratory of Immunopathology, Clinical Hospital, Federal University of Paraná, Curitiba, Paraná, Brazil.
Rheumatology (Oxford). 2010 Aug;49(8):1590-3. doi: 10.1093/rheumatology/keq134. Epub 2010 May 10.
To evaluate the prevalence of anti-cyclic citrullinated peptide (anti-CCP) antibodies and RF in RA patients and their relatives from Southern Brazil.
Anti-CCP2 and IgM-RF were evaluated in 156 RA patients and 200 relatives. Sera from 100 healthy unrelated individuals were used as control. The anti-CCP2 was detected by ELISA and the IgM-RF using the latex agglutination test.
We identified 117 anti-CCP2 (75%)-positive and 106 RF (67.9%)-positive patients. Anti-CCP2 was increased in relatives (5.5%; 11/200) when compared with unrelated individuals (1%; P = 0.050). Titre of anti-CCP2 in RA patients did not differ from relatives [140.4 (75.7) vs 115.6 (84.2) U, respectively; P = 0.30]. Positive relatives were younger than patients for anti-CCP2 (P = 0.0081), RF (P < 0.001) and both concomitantly (P = 0.012), and although there was no difference for anti-CCP2 positivity according to gender, increased RF positivity and concomitant anti-CCP2/RF were observed in the female relatives (P = 0.067 and 0.082, respectively). No difference regarding the relative degree of tobacco use in relatives was detected. Among the 11 anti-CCP2-positive relatives, 2 females had RA diagnosis established and 6 individuals presented with joint symptoms suggestive of RA.
The results demonstrate a significant positivity of anti-CCP2 in relatives of RA patients from Brazil and reinforce the importance of serological tools to identify undiagnosed RA.
评估来自巴西南部的类风湿关节炎（RA）患者及其亲属的抗环瓜氨酸肽（抗-CCP）抗体和 RF 的流行情况。
评估了 156 例 RA 患者和 200 名亲属的抗-CCP2 和 IgM-RF。使用 100 名健康无关个体的血清作为对照。抗-CCP2 通过 ELISA 检测，IgM-RF 通过乳胶凝集试验检测。
我们发现 117 例抗-CCP2（75%）阳性和 106 例 RF（67.9%）阳性患者。与无关个体（1%）相比，亲属中的抗-CCP2 增加（5.5%；11/200）（P=0.050）。RA 患者与亲属的抗-CCP2 滴度无差异[分别为 140.4（75.7）与 115.6（84.2）U；P=0.30]。阳性亲属的年龄小于患者，其抗-CCP2（P=0.0081）、RF（P<0.001）和两者均同时升高（P=0.012），尽管抗-CCP2 阳性率与性别无关，但在女性亲属中观察到 RF 阳性率和同时抗-CCP2/RF 升高（分别为 P=0.067 和 0.082）。在亲属中，未发现相对吸烟程度的差异。在 11 例抗-CCP2 阳性亲属中，有 2 例女性确诊为 RA，有 6 例出现关节症状提示 RA。
这些结果表明巴西 RA 患者亲属的抗-CCP2 阳性率显著升高，这强调了血清学工具在识别未确诊 RA 方面的重要性。
