ACF Antibody Diagnostic Accuracy Evaluated in Rheumatoid Arthritis

The anti-citrullinated fibrinogen (ACF) antibody has moderate diagnostic accuracy in rheumatoid arthritis (RA) and can be used as a complementary biomarker during diagnosis, according to a study published in the International Journal of Rheumatic Diseases.

This meta-analysis was designed to assess the overall diagnostic value of the ACF antibody in patients with RA. Studies included in the analysis were retrieved from the China National Knowledge Infrastructure, China Biology Medicine disc, PubMed, Wan Fang, Web of Science, and Chinese VIP databases. The Quality Assessment of Diagnostic Accuracy Studies-2 tool was used determine the quality of the eligible studies, meta-regression and subgroup analysis were used to explore sources of heterogeneity between the studies, and the possibility of publication bias was evaluated using Egger’s test.

Among the 7 studies included in the meta-analysis, the pooled sensitivity of ACF was 0.61 (95% CI, 0.57-0.64; P <.0001), the pooled specificity was 0.93 (95% CI, 0.92-0.94; P <.0001), the pooled positive likelihood ratio was 9.33 (95% CI, 5.15-16.92; P <.0001), the pooled negative likelihood ratio was 0.39 (95% CI, 0.30-0.53; P <.0001), the pooled diagnostic odds ratio was 24.58 (95% CI, 11.47-52.64), and the area under the curve was 0.8108. Meta-regression and subgroup analysis by factors such as ethnicity or whether the study included healthy controls did not show statistically significant differences and therefore may not be the source of heterogeneity. No significant publication bias was found.

The limitations of this meta-analysis include a small number of databases used, unavailability of unpublished research, heterogeneity in included studies, a failure to measure diagnostic accuracy of ACF in varying disease stages, and differing ACF cut-off values.

Investigators conclude that ACF can be used as a complementary biomarker in RA diagnosis, but the optimum cut-off value for ACF still needs to be confirmed, and the diagnostic accuracy of ACF as a biomarker in different stages of RA still needs to be measured.

Reference

Dai ZW, Wang ZH, Dong YY, et al. Diagnostic value of anti-citrullinated fibrinogen antibody in rheumatoid arthritis: a meta-analysis [published online February 6, 2019]. Int J Rheum Dis. doi: 10.1111/1756-185X.13477