To the Editor–We thank Allan-Blitz and Klausner [1] for the citations to their group–s work in this area and to the efforts underway to test diagnostics for quinolone resistance in Neisseria gonorrhoeae. Although our study investigated the genetic basis of resistance and assessed the positive and negative predictive values of specific mutations for resistance in the set of samples we analyzed [2], we take no position on the suitability of particular diagnostics. We note, however, that the US Food and Drug Administration has published guidance for antimicrobial susceptibility test systems [3]. The lower end of the range in negative predictive value cited by Allan-Blitz and Klausner (87.5%) is considerably lower than the 99% we observed, possibly owing to sampling from a different gonococcal population, in which alternative mechanisms of resistance may exist. This emphasizes the importance of establishing rates of major and very major discrepancy [3], as well as regularly monitoring the circulating gonococcal lineages to ensure the diagnostic test characteristics accurately reflect the distribution of resistance mechanisms in gonococci, which may vary over time and by geographic and demographic groups.
Notes
Disclaimer. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of General Medical Sciences or the National Institutes of Health.
Financial support. This work YHG was supported by the National Institutes of Health (grant K08-AI104767 to Y. H. G.). ML was supported by from the National Institute of General Medical Sciences (cooperative agreement U54GM088558 to M. L.).
Potential conflicts of interest. Both authors: no reported conflicts.
Both authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.
References
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