Chang Pi-Yueh, Yang Cheng-Tao, Cheng Ching-Hui, Yu Kuang-Hui
Department of Laboratory Medicine, Chang-Gung Memorial Hospital, Tao-Yuan, Taiwan.
Department of Medical Biotechnology and Laboratory Science, Tao-Yuan, Taiwan.
Int J Rheum Dis. 2016 Sep;19(9):880-6. doi: 10.1111/1756-185X.12552. Epub 2015 May 4.
To compare the diagnostic performance of rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibody (anti-CCP) in the diagnosis of patients with rheumatoid arthritis (RA) in Taiwan.
Serum concentrations of RF and anti-CCP were measured in 246 cases, including 39 patients with RA and 207 patients with other rheumatic diseases (non-RA). The age, sex, clinical presentation, RF, anti-CCP results and the final diagnoses were recorded and analyzed. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+) and negative likelihood ratio (LR-) were calculated.
Among all 246 patients, 39 (15.9%) were diagnosed with RA and 207 (84.1%) were diagnosed with other rheumatic diseases (non-RA). In the diagnosis of RA, the sensitivity, specificity, PPV, NPV, LR+ and LR- of the RF test were 67%, 79%, 37%, 93%, 3.12, and 0.42, respectively. The corresponding data for the anti-CCP test were 79%, 98%, 86%, 96%, 32.91 and 0.21, respectively. The presence of either anti-CCP or RF increased the sensitivity to 85%, and when they both were present, the specificity increased to 98%. Among the 39 RA patients, 26 (66.7%) tested positive for RF, and 31 (79.5%) tested positive for anti-CCP. RF was positive in two of eight anti-CCP-negative patients with RA, and anti-CCP was positive in seven of 13 RF-negative patients with RA.
The RF and anti-CCP tests are complementary, and the co-detection of these antibodies can increase the detection rate and provide important clinical value in the diagnosis of RA. Both anti-CCP and RF positivity are useful for the diagnosis of RA, and use of both tests together improves the diagnostic sensitivity.
比较类风湿因子（RF）和抗环瓜氨酸肽抗体（抗CCP）在台湾类风湿关节炎（RA）患者诊断中的诊断性能。
检测246例患者的血清RF和抗CCP浓度，其中包括39例RA患者和207例其他风湿性疾病（非RA）患者。记录并分析患者的年龄、性别、临床表现、RF、抗CCP检测结果及最终诊断。计算敏感性、特异性、阳性预测值（PPV）、阴性预测值（NPV）、阳性似然比（LR+）和阴性似然比（LR-）。
在全部246例患者中，39例（15.9%）被诊断为RA，207例（84.1%）被诊断为其他风湿性疾病（非RA）。在RA诊断中，RF检测的敏感性、特异性、PPV、NPV、LR+和LR-分别为67%、79%、37%、93%、3.12和0.42。抗CCP检测的相应数据分别为79%、98%、86%、96%、32.91和0.21。抗CCP或RF阳性可使敏感性提高至85%，两者均阳性时，特异性提高至98%。在39例RA患者中，26例（66.7%）RF检测阳性，31例（79.5%）抗CCP检测阳性。8例抗CCP阴性的RA患者中有2例RF阳性，13例RF阴性的RA患者中有7例抗CCP阳性。
RF和抗CCP检测具有互补性，联合检测这些抗体可提高RA诊断的检出率并具有重要临床价值。抗CCP和RF阳性均有助于RA诊断，两者联合使用可提高诊断敏感性。
