New diagnostic and evaluative tests for rheumatoid arthritis

To prevent joint destruction, it is important to diagnose RA early and to consider the prognosis. For this purpose, several new laboratory tests, such as IgG-RF, anti-agalactosyl IgG antibodies (CARF), and matrix metalloproteinase-3 (MMP-3), have become available for diagnosing RA. RF has a tolerable sensitivity of 68.5% for RA, but low specificity of 77.1%, and also 76.0% for patients with other rheumatic diseases and chronic inflammatory disease, respectively. CARF showed slightly higher sensitivity but low specificity for other rheumatic diseases and chronic inflammatory patients. In contrast, anti-cyclic citrullinated peptide antibody (anti-CCP), a new diagnostic test for RA, demonstrated significantly high specificity for other rheumatic diseases, and also for chronic inflammatory disease patients. Anti-CCP was superior to other laboratory tests by ROC analysis. Moreover, both CARF and anti-CCP had higher sensitivity of 66.7%, 61.5%, respectively, for the diagnosis of early RA than RF. On the other hand, MMP-3 is thought to be not only an evaluative test for the activity of RA because of its significant correlation with CRP, but also has potential as a prognostic test to identify joint damage from RA. Anti-CCP was also reported to associate with the progression of joint damage and may be also used as a prognostic test. We next examined the efficiency of RA diagnosis made by combining these laboratory tests. The specificity of RF was not as high as anti-CCP but reached 92% when combined with MMP-3. Thus, it is concluded that anti-CCP is superior to other laboratory tests in sensitivity and specificity, and that these combination assays are useful in the early diagnosis of RA.     

New biomarkers for rheumatoid arthritis

Rheumatoid factor (RF) has been commonly used as a biomarker of rheumatoid arthritis (RA). It is important to diagnose RA early and to prevent joint destruction before irreversible damage occurs. For this purpose, several new biomarkers, such as anti-cyclic citrullinated peptide antibody (anti-CCP) and matrix metalloproteinase-3 (MMP-3), have become available for both the diagnosis and prognosis of RA. RF showed a tolerable sensitivity of 68.5% for RA, but low specificity of 77.1% for patients with other rheumatic diseases. Anti-agalactosyl IgG antibodies (CARF) showed a slightly higher sensitivity of 73.9%, but specificity as low as that for RF. In contrast, anti-CCP demonstrated high sensitivity of 76.1% and marked specificity of 92.4% for patients with other rheumatic diseases. Anti-CCP was significantly superior to other biomarkers on receiver-operating characteristic curve (ROC) analysis. Moreover, meta-analysis revealed that the pooled sensitivity and specificity were 67% and 95% for anti-CCP, and 69% and 85% for RF, respectively, and that anti-CCP was more specific than RF for diagnosing RA. On the other hand, MMP-3 has been suggested to be a prognostic biomarker as well as an evaluative biomarker for RA. We next examined if the diagnostic accuracy of early RA is improved by combining these biomarkers. The specificity of RF was not as high as anti-CCP but rose to 92% when combined with MMP-3. Thus, we concluded that anti-CCP is superior to other biomarkers in terms of diagnostic accuracy, and that these combined assays are useful in the early diagnosis of RA.     

Topics on immunological tests for rheumatoid arthritis

To prevent joint destruction, it is important to diagnose RA early and to speculate the prognosis. Several new laboratory tests have been developed for this purpose. In addition to rheumatoid factor (RF), IgG-RF, anti-agalactosyl IgG antibodies (CARF), and matrix metalloproteinase 3 (MMP-3) have become available as diagnostic tests for RA. Among them, anti-cyclic citrullinated peptide antibodies (anti-CCP antibodies) have the sensitivity and specificity of 81.0% and 92.4%, respectively, which are superior to other laboratory tests by ROC analysis. Moreover, the specificity of anti-CCP antibodies to diagnose early RA was much higher than that of RF, although the sensitivity of CARF was slightly high compared with that of RF. In contrast, MMP-3 is thought to be an evaluative test for the activity of RA because a significant correlation was found between MMP-3 and CRP, but MMP-3 has a possibility as a prognostic test to know the joint damage of RA. We have shown that the progression of joint damage (Sharp score) was faster in MMP-3-positive patients than negative patients. Anti-CCP antibodies was also reported to associate with the progression of joint damage and may be used also as a prognostic test. We next examined how efficiently was the diagnosis of RA made by combining these laboratory tests. Although anti-CCP antibodies are highly specific to RA, the specificity of RF was not so high but became up to 92% when combined with MMP-3. In order to diagnose RA efficiently, we may firstly examine RF, next MMP-3 if RF is positive, and anti-CCP antibodies if RF is negative.     

Usefulness of anti-cyclic citrullinated peptide antibodies (anti-CCP) for the diagnosis of rheumatoid arthritis

Rheumatoid factor (RF) has been commonly used as a marker of rheumatoid arthritis (RA). RF can be detected in 60-80% of RA patients, but the specificity is low against other rheumatic diseases patients. We evaluated the diagnostic accuracy of anti-cyclic citrullinated peptide antibody (anti-CCP), a new diagnostic test for RA. Anti-CCP demonstrated higher sensitivity (81.0%) and specificity (92.4%). By the receiver operating characteristic (ROC) curve analysis, anti-CCP was superior to other markers (ie. RF, CARF, IgG-RF, and MMP-3). In early RA patients (RA patients who had had disease symptoms for < 2 years), sensitivity was 68.8%. Positivities of anti-CCP in RA patients became higher as the advance of stage defined by the Steinbrocker classification. We concluded that anti-CCP is a very valuable tool for the diagnosis of RA. Moreover, anti-CCP is a useful for finding RA of recent onset.     

RF、AKA和抗CCP抗体联检对类风湿关节炎诊断的临床价值

目的:探讨类风湿因子(Rheum atoid factor,RF)、抗角质蛋白抗体(antikeratin antibody,AKA)及抗环瓜氨酸肽(anti-cyc lic c itru llinated peptide,CCP)抗体对类风湿关节炎(rheum atoid arthritis,RA)的临床意义和早期应用价值。方法:对40例类风湿关节炎患者、30例系统性红斑狼疮和30名正常健康体检者进行RF、AKA、抗CCP抗体检测,应用速率散射比浊法测定RF,间接免疫荧光法检测AKA,ELISA法测定抗CCP抗体。结果:40例RA患者血清中,RF灵敏度和特异性分别为70.0%、90.0%,AKA灵敏度和特异性分别为35.0%、96.7%,抗CCP抗体灵敏度和特异性分别为85.0%、93.3%,联检RF、AKA及抗CCP抗体灵敏度和特异性分别为97.07%、99.8%。结论:RF、AKA和抗CCP抗体可作为诊断RA比较特异的血清学指标,三项指标联检可在一定程度上弥补RF对RA的诊断不足,提高RA的阳性诊断率,且有助于疾病的预后判断。     

Diagnostic performances of anti-cyclic citrullinated peptides antibody and antifilaggrin antibody in Korean patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease of unknown etiology. We studied the diagnostic performances of anti-cyclic citrullinated peptides antibody (anti-CCP) assay and recombinant anti-citrullinated filaggrin antibody (AFA) assay by enzyme linked immunosorbent assay (ELISA) in patients with RA in Korea. Diagnostic performances of the anti-CCP assay and AFA assay were compared with that of rheumatoid factor (RF) latex fixation test. RF, anti-CCP, and AFA assays were performed in 324 RA patients, 251 control patients, and 286 healthy subjects. The optimal cut off values of each assay were determined at the maximal point of area under the curve by receiver-operator characteristics (ROC) curve. Sensitivity (72.8%) and specificity (92.0%) of anti-CCP were better than those of AFA (70.3%, 70.5%), respectively. The diagnostic performance of RF showed a sensitivity of 80.6% and a specificity of 78.5%. Anti-CCP and AFA showed positivity in 23.8% and 17.3% of seronegative RA patients, respectively. In conclusion, we consider that anti-CCP could be very useful serological assay for the diagnosis of RA, because anti-CCP revealed higher diagnostic specificity than RF and AFA at the optimal cut off values and could be performed by easy, convenient ELISA method.     

抗-CCP抗体、RF与CRP联合检测对类风湿性关节炎早期诊断研究

目的探讨抗环瓜氨酸多肽（抗-CCP）抗体、类风湿因子（RF）与C-反应蛋白（CRP）联合检测在类风湿性关节炎（RA）中的诊断价值。方法采用半定量酶联免疫吸附法和定量免疫散色比浊法分别检测两组人群血清中的抗一CCP抗体、RF与C一反应蛋白（CRP）浓度,并分析上述三指标与RA的相关性。结果抗-CCP抗体诊断RA的特异度为93．5％,灵敏度为72．6％,RF为77．3％和83．4％,CRP为63．6％和82．3％,三者诊断灵敏度和特异度分别高达92．5％和97．6Voo。结论抗-CCP抗体诊断RA的特异度最高,RF的灵敏度最高,而三者联合早期诊断RA效率最好,与单一诊断指标相比具有明显的统计学意义。     

Analysis of clinical significance of anti-cyclic citrullinated peptide antibody (anti-CCP antibody) in rheumatoid arthritis (RA)]

OBJECTIVE: To examine clinical significance of anti-cyclic citrullinated peptide antibody (anti-CCP antibody) in RA. METHODS: Hundred fifteen patients with polyarthralgia (89 females, 26 males) were recruited, and subjected for the study. We studied anti-CCP antibody, ESR, CRP, IgM-RF, IgG-RF, RAPA, MMP-3, CARF, C1q-IC, Stage, Class, Joint score, Sharp score, KL-6, SP-D, chest CT. RESULTS: Anti-CCP antibody test had high specificity (93.5%). In RA with positive anti-CCP antibody, Sharp score (10.9+/-22.4) was higher than those with negative anti-CCP (1.7+/-1.8), and may serve as a prognostic marker of joint destruction (P<0.05). Anti-CCP antibody in RA with interstitial pneumonia is higher (84.5+/-36.4 U/mL) than those without interstitial pneumonia (52.6+/-44.7 U/mL) (P<0.05). CONCLUSION: Anti-CCP antibody is useful for diagnosis of RA, and could be a specific marker of joint destruction. Further investigation is necessary to clarify the relation of anti-CCP antibody with organ involvement and activity of RA.     

抗环瓜氨酸肽抗体检测对类风湿关节炎的临床诊断价值

目的探讨抗环瓜氨酸肽抗体（抗CCP抗体）检测对类风湿关节炎（RA）诊断的意义。方法采用酶联免疫吸附试验（ELISA）检测115份人血清的抗CCP抗体,同时采用免疫透射比浊法定量检测类风湿因子（RF）,包括40例RA患者,45例其它风湿病患者,30名正常人;并分析抗CCP抗体与RF实验结果之间的相关性。结果在40例RA病人中,抗CCP抗体的阳性率为80.0%,在其它风湿病人中的阳性率为7.0%,抗CCP抗体对RA的敏感性和特异性分别为80.0%、96.0%,其敏感性高于RF,但差异无统计学意义（P〉0.05）,特异性明显高于RF（P〈0.05）。联合应用抗CCP抗体与RF进行诊断,二者均阳性时敏感性为65.0%,特异性为97.3%。抗CCP抗体与RF实验结果之间无相关性。结论抗CCP抗体对RA具有较好的敏感性和很高的特异性,可与RF相互补充,联合检测可提高对RA早期诊断的准确性。     

类风湿因子及相关自身抗体对类风湿关节炎的诊断价值

目的探讨类风湿因子（RF）、抗环瓜氨酸肽抗体（抗CCP）及抗角蛋白抗体（AKA）联合检测对类风湿关节炎（RA）的临床诊断价值。方法对80例RA和65例非RA的其他自身免疫病患者检测RF、RF-IgM、抗CCP及AKA 4种指标。结果自身免疫性疾病女性发病较高,以RA组为甚;RA组的RF、RF-IgM、抗CCP及AKA高于其他自身免疫性疾病组;单指标检测RA诊断的敏感性为RF〉RF-IgM〉AKA〉抗CCP,特异性为RF-IgM〉抗CCP〉RF〉AKA。阳性预测值为抗CCP〉RF〉RF-IgM、AKA,阴性预测值为RF〉RF-IgM〉AKA〉抗CCP;以并联或串联方式联合检测均以RF、RF-IgM及抗CCP三联及RF、RF-IgM、抗CCP及AKA四联检测为佳,并联检测的敏感性分别为93%及97%,串联检测的特异性分别为98%及99%。结论 RF、RF-IgM、抗CCP及AKA 4种指标联合检测可提高对RA诊断的敏感性和特异性,对RA的早期诊断有较高价值。     

The diagnostic utility of anti-cyclic citrullinated peptide antibodies, matrix metalloproteinase-3, rheumatoid factor, erythrocyte sedimentation rate, and C-reactive protein in patients with erosive and non-erosive rheumatoid arthritis

OBJECTIVE: To compare the diagnostic utility of laboratory variables, including matrix metalloproteinase-3 (MMP-3), anticyclic citrullinated peptide (CCP) antibodies, rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) in patients with erosive and non-erosive rheumatoid arthritis (RA). METHODS: We assembled a training set, consisting of 60 patients with RA, all fulfilling the revised criteria of the American College of Rheumatology. A commercial enzyme linked immunosorbent assay (ELISA) was used both to test for anti-CCP antibodies (second generation ELISA kit) and MMP; RF were detected by latex-enhanced immunonephelometric assay. CRP was measured by latex turbidimetric immunoassay. RESULTS: The levels of anti-CCP antibody titers and ESR were significantly higher in patients with erosive disease than those in non-erosive RA patients (p < 0.001 and 0.0341) respectively. Moreover, a higher frequency of elevated titers of anti-CCP antibodies was found in RA patients with erosions compared to patients with non-erosive RA (78.3% vs. 43.2% respectively). The ROC curves of anti-CCP passed closer to the upper left corner than those other markers and area under the curve (AUC) of anti-CCP was significantly larger than AUC of other markers (0.755 for anti-CCP, 0.660 for ESR, 0.611 for CRP, 0.577 for RF, and 0.484 for MMP-3 female). A positive predictive value was higher for anti-CCP antibodies in comparison to other markers. We did not find significant statistical correlation between anti-CCP antibody titers and inflammatory markers such as ESR or CRP. However, we confirmed the correlation of elevated titers of anti-CCP antibodies and RF in both groups of patients whereas the degree of correlation was more significant in non-erosive patients. CONCLUSION: The results of our study suggest that the presence of elevated anti-CCP antibody titers have better diagnostic performance than MMP-3, RF, CRP and ESR in patients with erosive RA.     

A new strategy for the early diagnosis of rheumatoid arthritis: a combined approach

Rheumatoid arthritis [RA] is one of the most common and severe autoimmune rheumatic diseases, diagnosed primarily according to clinical manifestations and radiological reports. For many years, laboratory diagnosis of rheumatoid arthritis has relied on the detection of rheumatoid factor [RF], as established by the ACR criteria. A recent test to detect antibodies towards citrullinated peptides, called the anti-CCP assay, showed a similar sensitivity but a more elevated specificity than the RF test. Our intention was the recognition of an optimal diagnostic strategy that exhibits the highest sensitivity and specificity for RA detection. To this purpose, we examine the usefulness of autoantibodies in RA testing, evaluating the diagnostic performance of conventional and innovative assays for RF detection, and ELISA anti-CCP test, for anti-CCP antibodies detection, by a prospective study. Multiplex cytofluorimetric test appeared to be more sensitive and specific than nephelometric assay for RF detection. Hence, a novel combined approach, significantly increasing the diagnostic sensitivity for RA, was planned, employing the multiplex RF test in combination with the anti-CCP test.     

葡萄糖6-磷酸异构酶检测在类风湿关节炎中的意义

为评价葡萄糖6-磷酸异构酶(GPI)在类风湿关节炎(RA)诊断中的价值。检测225例RA患者,77例其他关节炎患者以及80例正常对照血清中GPI、抗环瓜氨酸肽(CCP)抗体和RF-IgM的水平。比较GPI、RF-IgM、抗CCP及GPI和抗CCP联合检测在RA的诊断中的意义,发现:①GPI、RF-IgM、抗CCP敏感性和特异性分别为59.11%、84.71%;77.78%、91.71%;65.33%、94.27%,抗CCP与GPI联合检测可明显提高诊断特异性,对RA诊断的敏感性和特异性分别为45.78%、97.45%;②GPI与抗CCP检测对RF阴性RA病例的诊断有一定价值(14%、26%);③GPI、抗CCP与RF-IgM之间均显著相关(P<0.01);④GPI与病程、功能分级、肿胀关节数、压痛关节数、握力及晨僵持续时间存在相关(P<0.01或P<0.05),而与X线分期、年龄和性别无关(P>0.05)。因之,GPI对RA有较高的诊断价值,CCP和GPI联合检测对RA有高度特异性,GPI能一定程度反映RA的临床病情,可作为RA的血清学指标。     

类风湿关节炎四种自身抗体的检测及意义

为评估类风湿因子(rheumatoid factor,RF)、抗环瓜氨酸肽(cyclic citrullinated pepdide,CCP)抗体、抗Sa抗体和抗角蛋白抗体(anti-keratin antibody,AKA)自身抗体对类风湿关节炎(rheumatoid arthritis,RA)诊断的意义,采用速率散...     

抗环瓜氨酸肽抗体、葡萄糖6-磷酸异构酶及类风湿因子的检测及对类风湿关节炎的诊断价值

目的为寻找敏感性高、特异性强的诊断类风湿关节炎(RA)的实验指标,选择抗环瓜氨酸肽(CCP)抗体、葡萄糖6-磷酸异构酶(GPI)和类风湿因子(RF)并探讨对RA的诊断价值。方法抗CCP抗体和GPI试验采用酶联免疫吸附(ELISA)法,RF用胶乳凝集法,检测了125例RA患者(RA组)、56例其他风湿性疾病患者(对照组)和36例健康体检者(正常组)血清中上述3者的浓度。结果抗CCP抗体、GPI及RF,在RA组分别是:(83.6±45.9)RU/ml、(2.8±2.3)μg/ml和(320.4±208.6)IU/ml;在对照组分别是:(36.2±15.3)RU/ml、(0.19±0.06)μg/ml和(36.3±12.5)IU/ml;在正常组分别是:(19.2±8.6)RU/ml、(0.16±0.08)μg/ml和(19.2±6.5)IU/ml。在RA组中,3者的敏感度分别是64.8%、73.6%和69.6%,特异性分别是92.0%、72.8%和74.4%。结论 RA患者血清抗CCP抗体、GPI和RF显著高于其他疾病患者(P<0.01)。抗CCP抗体和GPI有可能成为诊断RA的新指标、RA的血清标志物,对提高诊断RA的敏感性和特异性,具有良好的临床研究和推广价值。     

抗突变型瓜氨酸波形蛋白检测在类风湿关节炎中的意义

目的：评价抗突变型瓜氨酸波形蛋白（抗MCV）在类风湿关节炎（RA）诊断中的价值。方法：检测225例RA患者、77例其他关节炎患者以及80例正常对照血清中抗MCV、抗CCP和RF-IgM的水平,比较抗MCV、RF-IgM、抗CCP及抗MCV和抗CCP联合检测在类风湿关节炎的诊断中的意义。结果：①抗MCV、RF-IgM、抗CCP敏感性和特异性分别为74.67%、91.71%；77.78%、91.71%；65.33%、94.27%,抗MCV与抗CCP联合检测可明显提高诊断特异性,对RA诊断的敏感性和特异性分别为60.89%、99.36%；②抗MCV与抗CCP检测对RF阴性RA病例的诊断有一定价值（30%,26%）；③抗MCV、抗CCP与RF-IgM之间均显著相关（P〈0.01）；④抗MCV与年龄、病程、功能分级、压痛关节数、ESR、CRP、X线分期及晨僵持续时间存在相关（P〈0.01或P〈0.05）,而与性别、双手平均握力和肿胀关节数无关（P〉0.05）。结论：抗MCV对RA有较高的诊断价值,抗CCP和抗MCV联合检测对RA有高度特异性,抗MCV能一定程度反映RA的临床病情,可作为RA的血清学指标。     

Anti-Citrullinated Protein Antibodies in Rheumatoid Arthritis: As Good as it Gets?

Anti-citrullinated protein antibodies (ACPAs) have recently emerged as sensitive and specific serological markers of rheumatoid arthritis (RA), providing superior alternative of the rheumatoid factor (RF) test in the laboratory diagnostics of RA. The first members of this autoantibody family were anti-perinuclear factor (APF) and anti-keratin antibodies (AKA). It became evident that both APF and AKA recognize citrullinated epitopes of filaggrin. Citrullination is a post-translational modification of arginine by deimination, physiologically occurring during apoptosis, inflammation or keratinization. The presence of several citrullinated proteins has been demonstrated in the RA synovium. The identification of citrullinated epitopes as targets for anti-filaggrin antibodies led to the development of the first and later second generation anti-cyclic citrullinated peptide (anti-CCP) antibody assays. The widely used anti-CCP2 assays have high diagnostic sensitivity and specificity, and they also show important predictive and prognostic value in RA. The anti-Sa antibody has been identified a decade ago; however, recent studies confirmed that anti-Sa is directed against citrullinated vimentin, hence it is a new member of the family of ACPAs. The newly developed anti-mutated citrullinated vimentin (anti-MCV) assay has similar diagnostic performance than the anti-CCP2 ELISA; however, the diagnostic spectrum of the anti-MCV test is somewhat different from that of anti-CCP2. It’s especially useful in the diagnosis of RA in RF and anti-CCP2 seronegative patients. The combined application of anti-CCP2 and anti-MCV assays can improve the laboratory diagnostics of RA. The family of ACPAs is expected to expand; there is an increasing need for developing new diagnostic strategies after careful evaluation of the characteristics of the available assays. Zoltán Szekanecz and Lilla Soós with equal contribution.     

抗CCP抗体与RF联合检测在类风湿关节炎早期诊断中的意义

目的 探究抗CCP抗体与RF联合检测在类风湿关节炎早期诊断中的意义。方法 选取2017年11月~2018年11月我院收治的30例类风湿关节炎患者设为研究组,另选取同期进行健康体检者30例设为对照组,对两组进行抗CCP抗体与RF联合检测,并且分析抗CCP抗体、RF单独及两者联合检测的敏感性、特异性、阳性预测值和阴性预测值。结果 研究组抗CCP抗体阳性率96.67%、RF阳性率93.33%和两者联合检测阳性率86.67%均高于对照组的6.67%、3.33%及3.33%;研究组抗CCP抗体水平（78.65±14.33）U/ml和RF水平（314.22±20.56）IU/ml均高于对照组的（2.69±2.14）U/ml和（10.01±3.54）IU/ml（P＜0.05）。结论 对类风湿关节炎患者抗CCP抗体与RF的诊断敏感度拥有着一定的相似性,但抗CCP抗体特异度高于RF的特异度,若两者联合检测可极大提高敏感度,对于类风湿关节炎患者早期诊断工作的开展拥有着积极的推动作用。     

Prevalence of Autoantibodies to Cyclic Citrullinated Peptide in Patients with Rheumatic Diseases other than Rheumatoid Arthritis: A French Multicenter Study

Our objective was to evaluate the prevalence of autoantibodies to cyclic citrullinated peptides (anti-CCP aAbs) in a cohort of patients with a variety of inflammatory or non-inflammatory rheumatic diseases other than rheumatoid arthritis (RA). Six hundred and nine serum samples were tested for anti-CCP aAbs and for rheumatoid factor (RF) using enzyme-linked immunosorbent assays and immunonephelometry. The prevalence of anti-CCP aAbs and RF reached 10% and 25%, respectively, using the positive cutoff value suggested by the manufacturers. Using a higher cutoff value (50 U/ml) for both aAbs, the prevalence was lower with 6% and 16%, respectively. The specificity of both markers for RA thus reached 94% and 84%, respectively. Anti-CCP aAbs were found to be elevated in inflammatory and also in non-inflammatory rheumatic diseases in the same proportion. Clinical data obtained for 36 positive patients showed that 17% developed RA within 5 years. In conclusion, anti-CCP aAbs are clearly more specific than RF for RA. Follow-up of anti-CCP aAbs-positive patients with inflammatory or non-inflammatory rheumatic diseases other than RA could be important considering the predictive value of these aAbs for the development of RA.     

第二代抗环瓜氨酸肽抗体的检测在类风湿关节炎诊断中的意义

目的探讨抗环瓜氮酸肽（CCP）抗体的检测在类风湿关节炎（RA）诊断中的价值。方法ELISA法分别检测108例RA、89例非RA（其它风湿病患者）和78例健康体检者的抗CCP抗体；用间接免疫荧光法和速率散射比浊法检测抗角蛋白抗体（AKA）和类风湿因子（RF），分析CCP抗体的水平及与AKA、RF的相关性。结果抗CCP抗体的阳性率在RA中为87．4％（94／108），在非RA中为8．99％（8／89），正常人为0％（0／78）。3种抗体对RA诊断的敏感性和特异性分别为CCP87．4％、91．01％，AKA58．33％，82．24％，RF81．36％、75．35％。CCP抗体与AKA在RA患者血清中的阳性率之间差异非常显著，与RF差异不显著。3种方法的检测结果间存在相关性。结论用ELISA法检测血清中CCP抗体简便、结果可靠，对RA诊断具有高度的敏感性和特异性。