Aims. α-defensin is a biomarker which has been described as having
a high degree of accuracy in the diagnosis of periprosthetic joint
infection (PJI). Current meta-analyses are based on the α-defensin
laboratory-based immunoassay rather than the quick on-table lateral
flow test kit. This study is the first meta-analysis to compare the
accuracy of the α-defensin laboratory-based immunoassay and the
lateral flow test kit for the diagnosis of PJI. Materials and Methods. A systematic review was performed according to the Preferred
Reporting Items for Systematic Reviews and Meta-Analyses guidelines.
Inclusion criteria were all clinical studies where the diagnosis
of PJI was uncertain. All studies selected used the Musculoskeletal
Infection Society (MSIS) or modified MSIS criteria. Two independent
reviewers reviewed the studies and extracted data. A meta-analysis
of results was carried out: pooled sensitivity, specificity, positive
and negative likelihood ratio, heterogeneity and areas under curves
are reported. Results. Ten studies (759 patients) were included. Of these, seven studies
(640 patients) evaluated the laboratory-based α-defensin immunoassay
and three (119 patients) the lateral flow test. The pooled sensitivity
and specificity of the qualitative α-defensin laboratory immunoassay
was 0.953 (95% confidence interval (CI) 0.87 to 0.984) and 0.965 (95%
CI 0.943 to 0.979) respectively. The pooled positive likelihood
ratio (PLR) and negative likelihood ratio (NLR) were 34.86 (95%
CI 19.34 to 62.85) and 0.02 (95% CI 0.00 to 0.11). The pooled sensitivity
and specificity of the lateral flow test were 0.774 (95% CI 0.637
to 0.870) and 0.913 (95% CI 0.828 to 0.958), respectively. The pooled
PLR and
