The diagnostic value of polymerase chain reaction for ocular tuberculosis diagnosis in relation to antitubercular therapy response: a meta-analysis

Background: Polymerase chain reaction (PCR) is currently considered the method of choice for diagnosing ocular tuberculosis. However, the sensitivity and specificity of PCR using ocular samples remain uncertain. Our meta-analysis aimed to review the diagnostic accuracy of PCR testing in confirming ocular tuberculosis, with responses to antitubercular therapy (ATT) as reference indices. Methods: A systematic literature search of the PubMed, EBSCOHost, Scopus, and Google Scholar databases was performed using the standardized PRISMA guideline. Observational studies reporting both PCR MTb positivity and ATT response were included. Meta-analysis was performed to estimate the pooled positivity rate, sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratios (DOR), and summary receiver operating curves (SROC). Results: The pooled positivity rate for PCR MTb was 0.55 (95% CI 0.44–0.67). The overall sensitivity and specificity were 88% (95% CI 83–92) and 71% (95% CI 60–80), respectively. The pooled DOR was 12.15 (95% CI 5.55–26.62). The area under the SROC was 0.83. Conclusions: The diagnostic accuracy of PCR Mtb is not sufficient for use as a benchmark for ocular TB diagnosis routinely based on ATT response. A negative result may help avoid prescribing unnecessary ATT in dilemmatic cases.