Department of Medical Microbiology, College of Medicine, University of Ibadan, Ibadan, Nigeria.
Sex Transm Dis. 2011 Apr;38(4):329-33. doi: 10.1097/OLQ.0b013e3181fc695a.
To detect and type plasmids responsible for penicillin and tetracycline resistance in Neisseria gonorrhoeae isolates using a novel duplex polymerase chain reaction (PCR) assay.
A duplex PCR assay, to detect and type penicillinase-producing N. gonorrhoeae (PPNG), and plasmid-mediated tetracycline resistant N. gonorrhoeae (TRNG), was developed on the basis of published single assays. Gonococcal Isolate Surveillance Project control strains were used in assay development and then 209 consecutive N. gonorrhoeae isolates, collected from men with urethral discharge in 2008, were tested. Controls included Asia, Africa, and Toronto β-lactamase plasmids, as well as American and Dutch TRNG plasmids. PCR amplicons were detected using an Agilent 2100 Bioanalyzer. Minimum inhibitory concentrations (MIC) were determined with E tests. Penicillinase production was detected using Nitrocefin solution.
Among 209 gonococcal isolates, 54 (25.8%) PPNG and 154 (73.3%) TRNG were detected. The MIC50 and MIC90 values were determined for penicillin (0.19 and 32 mg/L) and tetracycline (6 and 16 mg/L). The assay detected the Africa-type (35.2%), the Toronto-type (44.4%), and a new type (20.3%) of β-lactamase plasmid. The American-type TRNG plasmid was 3-fold more frequent as compared with the Dutch-type. Although there was no overall association between the detection of PPNG and TRNG plasmids, only American type TRNG contained β-lactamase-encoding plasmids (P < 0.0001).
The prevalence of plasmid-mediated resistance to tetracycline, and to a lesser extent penicillin, is high and neither drug is likely to have any future role in the treatment of gonorrhoea in South Africa. A novel β-lactamase plasmid was detected during the study and requires further characterization.
使用新型双重聚合酶链反应（PCR）检测淋病奈瑟菌分离株中引起青霉素和四环素耐药的质粒，并对其进行分型。
在已发表的单项检测的基础上，建立了一种用于检测和分型产青霉素酶淋病奈瑟菌（PPNG）和质粒介导的四环素耐药淋病奈瑟菌（TRNG）的双重 PCR 检测方法。在检测方法的开发过程中使用了淋球菌分离监测项目的对照菌株，然后对 2008 年从尿道分泌物中采集的 209 例连续淋病奈瑟菌分离株进行了检测。对照品包括亚洲、非洲和多伦多β-内酰胺酶质粒，以及美国和荷兰 TRNG 质粒。使用安捷伦 2100 Bioanalyzer 检测 PCR 扩增产物。采用 E 试验法测定最小抑菌浓度（MIC）。使用硝基头孢菌素溶液检测青霉素酶的产生。
在 209 例淋球菌分离株中，检测到 54 株（25.8%）PPNG 和 154 株（73.3%）TRNG。青霉素的 MIC50 和 MIC90 值分别为 0.19 和 32mg/L，四环素的 MIC50 和 MIC90 值分别为 6 和 16mg/L。该检测方法检测到了非洲型（35.2%）、多伦多型（44.4%）和新型（20.3%）β-内酰胺酶质粒。美国型 TRNG 质粒比荷兰型更为常见（3 倍）。虽然 PPNG 和 TRNG 质粒的检测之间没有总体关联，但只有美国型 TRNG 含有β-内酰胺酶编码质粒（P<0.0001）。
质粒介导的对四环素的耐药性（以及在较小程度上对青霉素的耐药性）的流行率很高，在南非，这两种药物都不太可能在淋病治疗中发挥作用。在研究过程中发现了一种新型β-内酰胺酶质粒，需要进一步进行特征描述。
