Emergence of meningococci with reduced susceptibility to third-generation cephalosporins.

Abstract : OBJECTIVES: Reduced susceptibility to penicillin G in Neisseria meningitidis is mainly due to alterations in PBP2 encoded by the penA gene. However, this phenotype was not associated with reduced susceptibility to third-generation cephalosporins (C3Gs). We aimed to study the emergence of meningococci with reduced susceptibility to C3Gs (MIC >0.06 mg/L) in France since 2012. METHODS: Invasive meningococcal isolates were typed by MLST and penA sequencing and their antibiotic susceptibility was tested. RESULTS: Isolates with reduced susceptibility to C3Gs represented 2% of all invasive isolates from 2012-15, but were absent before. They harboured a new penA allele, penA327, that was also detected in isolates from urethritis cases and in gonococci. CONCLUSIONS: Surveillance of these isolates should be enhanced as they may jeopardize the use of C3Gs in the management of invasive meningococcal disease.