English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background  The recent emergence of azithromycin-resistant (AZM-R)  N. gonorrhoeae  isolates that have coevolved decreased susceptibility to extended-spectrum cephalosporins has caused great concern. Here we investigated the prevalence of decreased susceptibility to ceftriaxone (CRO D ) in AZM-R isolates and genetically characterized AZM-R isolates in Guangzhou, China from 2009 to 2013.    Methods  The minimum inhibitory concentration (MIC) of AZM and ceftriaxone was determined using an agar-dilution method. All AZM-R isolates were screened for mutations in 23S rRNA,  mtrR  and penA genes and genotyped using  N. gonorrhoeae  multi-antigen sequence typing (NG-MAST).    Results  Of the 485 identified  N. gonorrhoeae  isolates, 445 (91.8 %) were isolated from male urethritis subjects, and 77 (15.9 %) were AZM-R (MIC ≥ 1 mg/L), including 33 (6.8 %) with AZM low-level resistant (AZM-LLR, MIC = 1 mg/L) and 44 (9.1 %) with AZM middle-level resistant (AZM-MLR, MIC ≥ 2 mg/L). Significantly more CRO D  (MIC ≥ 0.125 mg/L) showed in AZM-MLR isolates (43.2 %, 19/44) as compared with that in AZM-LLR isolates (18.2 %, 6/33) ( p  < 0.05). For the 23S rRNA,  mtrR , penA or combined 23S rRNA/ MtrR /penA mutations, no significant difference was found between AZM-LLR isolates and AZM-MLR isolates ( P  > 0.05); similar results were detected between combined AZM-LLR/CRO D  isolates and combined AZM-MLR/CRO D  isolates ( P  > 0.05). No mutation A2059G or AZM high-level resistant (AZM-HLR, MIC ≥ 256 mg/L) isolate was detected. Among 77 AZM-R isolates, 67 sequence types (STs) were identified by NG-MAST, of which 30 were novel. Most STs were represented by a single isolate.    Conclusions  The AZM-R together CRO D  isolates are now present in Guangzhou, China, which deserve continuous surveillance and the mechanism of concurrent resistance needs further study.    Electronic supplementary material  The online version of this article (doi:10.1186/s12879-016-1469-3) contains supplementary material, which is available to authorized users.

bmc infectious diseases

Azithromycin-resistant Neisseria gonorrhoeae isolates in Guangzhou, China (2009–2013): coevolution with decreased susceptibilities to ceftriaxone and genetic characteristics