Fluoroquinolone resistance in Neisseria meningitidis in Spain.
OBJECTIVE
To assess the ciprofloxacin resistance of Neisseria meningitidis isolated from 1999 through 2006 in Spain, susceptibility testing was conducted on 5300 isolates.


METHODS
Ten isolates showed MICs of ciprofloxacin ranging between 0.06 and 0.25 mg/L, and they were characterized by analysis for mutations within the quinolone resistance determining regions (QRDRs) in the gyrA, gyrB, parC and parE genes. Mutations in the mtrR gene were also analysed.


CONCLUSIONS
Single mutations in gyrA appeared to be the main mechanism involved, Thr-91-->Ile being the most frequent substitution seen. Two meningococci had four different gyrA substitutions. No mutations in the QRDRs of the parC and gyrB genes were detected, and three strains showed a His-495-->Asn substitution in the parE gene. In addition, two different alterations in the mtrR gene affecting the expression of the MtrCDE efflux system were identified which may also contribute to the reduced susceptibility to quinolones seen in three strains.
Enríquez
Rocío
R
Reference Laboratory for Meningococci, Servicio de Bacteriología, National Centre for Microbiology, National Institute of Health Carlos III, Majadahonda, Madrid, Spain.
Abad
Raquel
R
Salcedo
Celia
C
Pérez
Sonia
S
Vázquez
Julio A
JA
D000293:Adolescent; D000328:Adult; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial / Q000187:drug effects* / Q000502:physiology; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests / Q000379:methods; D009345:Neisseria meningitidis / Q000187:drug effects* / Q000502:physiology; D013030:Spain / Q000453:epidemiology
D024841:Fluoroquinolones