Culture-free genotyping of Neisseria gonorrhoeae revealed distinct strains at different anatomical sites in a quarter of patients, the Netherlands, 2012 to 2016

• Published in: Euro surveillance : bulletin européen sur les maladies transmissibles Vol. 23; no. 50; p. 1
• Main Authors: van der Veer, Brian Mjw, Wolffs, Petra Fg, Hoebe, Christian Jpa, Dukers-Muijrers, Nicole Htm, van Alphen, Lieke B
• Format: Journal Article
• Language: English
• Published: Sweden Centre Europeen pour la Surveillance Epidemiologique du SIDA (European Centre for the Epidemiological Monitoring of AIDS) 13.12.2018; European Centre for Disease Prevention and Control (ECDC)
• Subjects: Adult; Bacteriology; Female; Genotype; Genotype & phenotype; Gonorrhea; Gonorrhea - diagnosis; Gonorrhea - epidemiology; Gonorrhea - microbiology; Gonorrhea - transmission; Gram-negative bacteria; Histology; Homosexuality, Male; Humans; Male; Middle Aged; Molecular Epidemiology - methods; Neisseria gonorrhoeae - classification; Neisseria gonorrhoeae - genetics; Neisseria gonorrhoeae - isolation & purification; Netherlands - epidemiology; Polymerase Chain Reaction - methods; Sensitivity and Specificity; Sentinel Surveillance; Strain; Netherlands; concurrent infections; gonorrhoeae; surveillance; Neisseria; genotyping
• ISSN: 1560-7917; 1025-496X; 1560-7917
• DOI: 10.2807/1560-7917.ES.2018.23.50.1800253

BackgroundGenotyping of (NG) is essential for surveillance to monitor NG transmission and dissemination of resistant strains. Current genotyping methods rely on bacterial culture which frequently fails.AimOur aim was to develop a culture-free genotyping method that is compatible with the widely used multi-antigen sequence typing (NG-MAST) database, which facilitates genotyping of NG detected at separate anatomical sites in individual patients.MethodsSpecific primers for both PCR targets and were designed and technically validated by assessing the analytical sensitivity, cross-reactivity with 32 non-gonoccocal species, and concordance with NG-MAST. Clinical application was assessed on 205 paired samples from concurrent NG infections at different anatomical sites of 98 patients (81 men who have sex with men and 17 women) visiting our sexually transmitted infections clinic.ResultsTyping could be consistently performed on samples with a PCR quantification cycle (Cq) value <35. Furthermore, the method showed no cross-reactivity and was concordant with NG-MAST. Culture-free NG-MAST improved the typing rate from 62% (59/95) for cultured samples to 94% (89/95) compared with culture-dependent NG-MAST. Paired samples of 80 of 98 patients were genotyped, revealing distinct NG strains in separate anatomical sites in 25% (20/80) of the patients.ConclusionsThis NG-specific genotyping method can improve NG surveillance as it facilitates genotyping of non-culturable and extra-genital samples. Furthermore, 25% of patients were infected with multiple NG strains, which is missed in current culture-dependent surveillance. Including non-culturable and concurrent NG infections in surveillance informs actions on dissemination of multidrug-resistant NG strains.