title: Identification of intrinsically metronidazole-resistant clades of Gardnerella vaginalis.
abstract: Gardnerella vaginalis is associated with bacterial vaginosis (BV), the most common cause of vaginal discharge. Metronidazole is a front-line therapy for BV, and treatment failure and recurrent disease are common problems. Whole-genome sequencing studies have revealed that G. vaginalis has a population structure that consists of 4 clades: clades 1 and 3 are associated with BV, whereas clades 2 and 4 are not. To determine if metronidazole susceptibility is associated with population structure, we analyzed 87 clinical isolates and found that metronidazole resistance (MIC ≥32 μg/mL) was highly associated with clade (P<0.0001), as 14/14 clade 3 isolates (100%) and 22/22 clade 4 isolates (100%) exhibited resistance, compared to only 16/37 clade 1 isolates (35%) and 1/14 clade 2 isolates (7.1%). The identification of intrinsically metronidazole-resistant G. vaginalis clades will facilitate future studies on the relationship between metronidazole resistance and BV treatment failure.
authors.affiliation: Femeris Women's Health Research Center, Medical Diagnostic Laboratories, A Member of Genesis Biotechnology Group, 2439 Kuser Rd., Hamilton, NJ, USA.
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Schuyler
authors.affiliation: Femeris Women's Health Research Center, Medical Diagnostic Laboratories, A Member of Genesis Biotechnology Group, 2439 Kuser Rd., Hamilton, NJ, USA.
authors.forename: Eli
authors.initials: E
authors.lastname: Mordechai
authors.affiliation: Femeris Women's Health Research Center, Medical Diagnostic Laboratories, A Member of Genesis Biotechnology Group, 2439 Kuser Rd., Hamilton, NJ, USA.
authors.forename: Martin E
authors.initials: ME
authors.lastname: Adelson
authors.affiliation: Division of Infectious Diseases, Wayne State University School of Medicine, 540 E. Canfield St., Detroit, MI, USA.
authors.forename: Jack D
authors.initials: JD
authors.lastname: Sobel
authors.affiliation: Femeris Women's Health Research Center, Medical Diagnostic Laboratories, A Member of Genesis Biotechnology Group, 2439 Kuser Rd., Hamilton, NJ, USA.
authors.forename: Scott E
authors.initials: SE
authors.lastname: Gygax
authors.affiliation: Femeris Women's Health Research Center, Medical Diagnostic Laboratories, A Member of Genesis Biotechnology Group, 2439 Kuser Rd., Hamilton, NJ, USA. Electronic address: dhilbert@femeris.com.
authors.forename: David W
authors.initials: DW
authors.lastname: Hilbert
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D005260:Female; D006194:Gardnerella vaginalis / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D005838:Genotype; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology; D006801:Humans; D008795:Metronidazole / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D016585:Vaginosis, Bacterial / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D008795:Metronidazole
keywords: Bacterial vaginosis; Gardnerella vaginalis; Metronidazole