A systematic review and meta-analysis of different diagnostic procedures to detect gonococcus infection in resource-limited scenario

Abstract

Context: Neisseria gonorrhoeae is a Gram-negative diplococcus, an obligate human pathogen, and the etiologic agent of the sexually transmitted infection (STI), gonorrhoea. culture is the standard procedure for diagnosis, which may be supported by nucleic acid tests and microscopy.

Aims: To determine the best possible method of diagnosis for Gonococcus infection in resource-limited settings.

Settings and design: The meta-analyses were designed to determine the difference in diagnosis between Culture and nucleic acid amplification tests (NAATs) and also between the different Amplification Tests and widely available Roche COBAS AMPLICOR test.

Subjects and methods: Databases searched were Pubmed, Medline, Google Scholar and Cochrane reviews. Risk ratio (RR) with 95% confidence intervals was estimated for the dichotomous outcomes. The random-effect model was applied for all the studies in the analysis.

Statistical analysis used: The meta-analysis was computed in RevMan Version 5.3, Copenhagen, Denmark.

Results: In the first analysis, NAATs significantly improved the chances of detection in comparison to the standard culture and final RR was 1.24 (1.05-2.51), which put the diamond on the right of no-effect axis, indicating more positives by NAATs. In the second analysis, AMPLICOR had the more positive results, which may have indicated better detection rate, as well as less specificity and final RR was 0.809 (0.737-0.888), which put the diamond on the left of the non-effect axis, indicating more positives by AMPLICOR.

Conclusions: In a resource-limited scenario like India, the syndromic management of STIs are considered to be the norm. A positive diagnosis is only given if the tests are confirmed by Culture, as it is still considered to be the gold standard of diagnosis. However, in many cases, due to suboptimal transportation and lack of proper handling, culture in unable to grow even if the patient is infected. In such cases, Nucleic Acid Tests should be able to detect an infection.

Keywords: Diagnostic procedures; Neisseria gonorrhoeae; meta-analysis.