Diagnostic Test Accuracy of Commercial Tests for Detection of Shiga Toxin–Producing Escherichia coli: A Systematic Review and Meta-Analysis

BACKGROUND: Rapid detection of Shiga toxin–producing Escherichia coli (STEC) enables appropriate monitoring and treatment. We synthesized available evidence to compare the performance of enzyme immunoassay (EIA) and PCR tests for the detection of STEC. METHODS: We searched published and gray literature for studies of STEC EIA and/or PCR diagnostic test accuracy relative to reference standards including at least one nucleic acid amplification test. Two reviewers independently screened studies, extracted data, and assessed quality with the second version of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Bivariate random effects models were used to meta-analyze the clinical sensitivity and specificity of commercial EIA and PCR STEC diagnostic tests, and summary receiver operator characteristic curves were constructed. We evaluated the certainty of evidence with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. RESULTS: We identified 43 articles reflecting 25 260 specimens. Meta-analysis of EIA and PCR accuracy included 25 and 22 articles, respectively. STEC EIA pooled sensitivity and specificity were 0.681 (95% CI, 0.571–0.773; very low certainty of evidence) and 1.00 (95% CI, 0.998–1.00; moderate certainty of evidence), respectively. STEC PCR pooled sensitivity and specificity were 1.00 (95% CI, 0.904–1.00; low certainty of evidence) and 0.999 (95% CI, 0.997–0.999; low certainty of evidence), respectively. Certainty of evidence was downgraded because of high risk of bias. CONCLUSIONS: PCR tests to identify the presence of STEC are more sensitive than EIA tests, with no meaningful loss of specificity. However, given the low certainty of evidence, our results may overestimate the difference in performance.