淋球菌gyrA和parC基因突变与氟喹诺酮类药物关系的研究

目的：探讨淋球菌gyrA和parC基因突变与淋球菌耐氟喹诺酮类药物之间的关系。方法：①纸片扩散法检测58株淋球菌对5种氟喹诺酮类药物的敏感性。②E测定法定量检测环丙沙星的最小抑菌浓度（MIC）。③PCR技术扩增gyrA和parC基因的喹诺酮耐药决定区（QRDR）相关序列并作测序分析。结果：①对环丙沙星、氧氟沙星、氟罗沙星、洛美沙星、依诺沙星同为敏感、中介、耐药者分别为2株、4株和39株。②环丙沙星MIC为敏感、中介、耐药分别为2株、17株和39株。③环丙沙星MIC为0．004－0．016μg/mL的2株淋球菌gyrA和parC基因均未发生突变；MIC为0．064－0．094μg/mL的菌株仅发生gyrA单位点突变；而MIC≥0.25μg/mL的菌株均发生gyrA双位点突变。MIC≤0．25μg/mL的菌株无parC基因突变，而MIC≥1.0μg/mL的菌株除出现gyrA双位点突变外均同时发生parC单位点突变。④在发生突变的16株菌中，Ser91(TCC)→Phe(TTC）突变为15株。结论：①gyrA基因突变介导淋球菌对氟喹诺酮类药物低和中水平耐药，而对氟喹诺酮类药物高水平耐药需要parC基因突变的共同参与。②gyrA基因Ser91→Phe的突变是导致淋球菌对氟喹诺酮类药物耐药的关键突变。     

广州地区106株淋球菌中脂蛋白分型与环丙沙星耐药相关性研究

目的:研究广州地区106株淋球菌中脂蛋白分型与环丙沙星耐药的相关性.方法:用糖琼脂稀释法测定淋球菌对环丙沙星的MIC值,PCR分别扩增淋球菌的gyrA、parC和脂蛋白基因并测序分析.结果:广州地区106株淋球菌对环丙沙星的耐药率为95 3%,共有19个脂蛋白亚型,最常见的亚型是17c,有49株(46 2%).对环丙沙星耐药的101株菌中,所有菌株在gyrA基因对应氨基酸的第91和95位点上均发生了突变,而parC基因随着MIC值的升高发生位点突变的概率呈上升趋势.在中低水平耐药组中,最常见的脂蛋白亚型是17c和14d,均有12株(28 6%).在高水平耐药组中,最常见的脂蛋白亚型是17c,有35株(59 3%),其次是14d,有11株(18 6%).结论:淋球菌脂蛋白亚型的分布存在地域性,与环丙沙星耐药程度高低无明显相关性.     

淋球菌对头孢曲松的敏感性及淋球菌多抗原测序分型研究

【摘要】 目的 探讨南京市淋球菌对头孢曲松的敏感性以及相应菌株的淋球菌多抗原测序分型（NG-MAST）基因型别。 方法 2007年和2012年在中国疾病预防控制中心性病控制中心临床防治基地分别收集了204株和81株淋球菌,经过分离纯化及鉴定后,用琼脂稀释法测定其对头孢曲松的最小抑菌浓度（MIC）;菌株培养后利用试剂盒提取DNA,并进行淋球菌多抗原测序分型（NG-MAST）。 结果 测试的285株淋球菌MIC ≥ 0.060 μg/ml的菌株比例为63.2%,MIC ≥ 0.125 μg/ml的比例为31.6%。2012年MIC ≥ 0.060 μg/ml和MIC ≥ 0.125 μg/ml的菌株比例分别为44.4%和11.1%,2007年MIC ≥ 0.060 μg/ml和MIC ≥ 0.125 μg/ml的菌株比例分别为70.6%和39.7%。NG-MAST分型研究显示,285株淋球菌共有166个型别,菌株多样性较高,其中73种为已知型别,93种为新型别。2007年测定的所有菌株中以ST568（n = 13）,ST270（n = 9）,ST421（n = 7）,ST2288（n = 5）,ST1731（n = 4）,ST1766（n = 4）,ST1866（n = 4）,ST1870（n = 4）等为主。2012年测定的所有菌株中以ST2318（n = 5）,ST1053（n = 4）,ST5990（n = 4）,ST8726（n = 4）为主。相同NG-MAST型别的菌株具有相同或相近的MIC值。 结论 2012年与2007年菌株的优势型别有较大变化,某些型别与头孢药敏值有较强对应关系。NG-MAST分型可能作为分子生物学标记用于淋球菌耐药监测。     

淋球菌对大观霉素耐药基因的初步检测

【摘要】 目的 检测导致大观霉素耐药的淋球菌16S rRNA基因中的突变位点。 方法 对6株大观霉素耐药淋球菌［最小抑菌浓度（MIC） ≥ 128 mg/L］、20株大观霉素敏感菌株（MIC 32 mg/L和16 mg/L各10株）的16S rRNA基因进行DNA扩增和序列测定,分析16S rRNA基因突变情况。 结果 6株大观霉素耐药淋球菌的16S rRNA基因均发生了突变,其中2株（MIC > 256 mg/L）为C1192T突变,1株（MIC 256 mg/L）为C1344T和T1345A突变,1株（MIC 256 mg/L）为T990G和T991C突变,1株（MIC 128 mg/L）为T990G、G1343C和C1344T突变,1株（MIC 128 mg/L）为T991C突变。20株大观霉素敏感菌株均未发生突变。 结论 淋球菌16S rRNA基因不同位点突变可能与大观霉素不同程度的耐药相关,C1192T突变可能导致高度耐药,其他单一位点或多位点突变与不同程度的耐药相关。 【关键词】 奈瑟球菌,淋病; 壮观霉素; 点突变; RNA,核糖体,16S; 抗药性,细菌     

广州地区106株淋球菌中脂蛋白分型与环丙沙星耐药相关性研究

目的:研究广州地区106株淋球菌中脂蛋白分型与环丙沙星耐药的相关性.方法:用糖琼脂稀释法测定淋球菌对环丙沙星的MIC值,PCR分别扩增淋球菌的gyrA、parC和脂蛋白基因并测序分析.结果:广州地区106株淋球菌对环丙沙星的耐药率为95 3%,共有19个脂蛋白亚型,最常见的亚型是17c,有49株(46 2%).对环丙沙...     

中山地区淋球菌头孢菌素敏感性及NG-MAST研究

目的：研究中山辖区淋球菌对头孢曲松与头孢克肟的敏感性,及淋球菌多抗原测序分型(NG-MAST)的基因型别。方法：收集2017-2018年中山市辖区医疗机构淋球菌菌株,经分离、鉴定和纯化后,采用琼脂稀释法检测其对头孢曲松与头孢克肟的最小抑菌浓度(MIC);应用NG-MAST进行淋球菌porB和tbpB外膜蛋白基因分型。结果：共检测193株淋球菌,对头孢曲松、头孢克肟的低敏率分别为5.2％和13.5％;NG-MAST分型显示193株菌共有125个型别,其中65种为已知型别,60种为新型别;所检菌株以ST5308、ST5061、ST2268、NEW1、ST10091、NEW2和NEW3为优势型别,并且同型别菌株对同一抗生素的MIC值相同或相近。结论：头孢曲松和头孢克肟作为淋病治疗的一线药物,已出现低敏;本地区淋球菌porB和tbpB外膜蛋白出现新的基因型别。     

广东省珠海地区淋球菌多抗原序列分型研究

 目的:了解广东省珠海地区淋球菌基因型的分布,为淋病的防控提供实验室依据。方法：采用淋球菌多抗原序列分型法（NG-MAST）对2018-2019年珠海市淋病监测网络收集的172株淋球菌菌株进行基因分型,并构建系统进化树。结果：172株淋球菌中,porB基因型82种,tbpB基因型44种;porB和tbpB基因型别前三位分别为por2978（13株）、por1135（11株）、por3215(9株) 和tbp10（37株）、tbp21（26株）、tbp110（13株）。NG MAST型别79种,未知基因型占33.7%,优势基因型为ST9659（9株）、ST5308（6株）、ST8140（6株）,系统进化树显示菌株具有高度多态性。结论：本地区NG MAST型别具有多样性,新基因型菌株较多。     

广西地区淋病奈瑟菌对头孢菌素的耐药性及多抗原测序分型

目的了解广西地区淋病奈瑟菌对两种头孢菌素药物的耐药性及对应菌株多抗原测序分型(NGMAST)情况。方法从2012-2014年广西地区性病门诊患者尿道或宫颈收集分泌物培养共195株淋病奈瑟菌,经过分离纯化及鉴定后,用琼脂稀释法测定其对头孢曲松和头孢克肟的最小抑菌浓度(MIC),并进行淋病奈瑟菌多抗原测序分型(NG-MAST),数据统计采用SPSS13.0软件分析。结果2012-2014年从性病门诊淋病患者中收集临床分离菌株195株,其对头孢曲松的MIC≥0.060mg/L的菌株比例为8.21%;对头孢克肟的MIC≥0.060mg/L的菌株比例分别为11.28%。NG-MAST分型结果显示,195株淋病奈瑟菌共有147个型别,型别多样性很高,其中118种为已知型别,29种为新型别。所有菌株中以ST10380(n=5),ST621(n=4),ST1927(n=4),ST2318(n=4),ST3741(n=4),ST4539(n=4),ST1768(n=3),ST2770(n=3),ST6312(n=3)为优势型别。结论广西地区淋病奈瑟菌NGMAST型别具有丰富多样性,某些型别与头孢曲松和头孢克肟的MIC值有较强对应关系。NG-MAST分型可用于本地区淋病奈瑟菌耐药监测的辅助工具。     

中国部分地区淋球菌耐药监测点产青霉素酶淋球菌及其blaTEM-135突变体的流行调查

目的 了解中国不同地区淋球菌耐药监测点产青霉素酶淋球菌（PPNG）的比例及blaTEM-135突变体在PPNG中的分布,比较PPNG及blaTEM-135突变体淋球菌多抗原测序分型（NG-MAST）的型别分布,了解不同地区PPNG blaTEM-135突变体的差异与联系。 方法 2012年在江苏、上海、浙江、天津、广东、广西6个淋球菌耐药监测点共收集572株淋球菌,经过分离纯化及鉴定后,采用头孢噻吩纸片法测定PPNG;菌株培养后利用试剂盒提取DNA,通过错配扩增突变分析PCR（MAMA PCR）鉴定blaTEM-135突变体,采用NG-MAST进行分型研究。 结果 572株淋球菌中PPNG总阳性率为38.1%（218/572）,PPNG中相应blaTEM-135突变体的总比例为52.3%（114/218）。监测点中PPNG阳性率从高至低分别为：浙江（45/87,51.7%）、上海（36/79,45.6%）、广东（78/205,38.0%）、广西（12/32,37.5%）、江苏（24/77,31.2%）、天津（23/92,25%）;PPNG中相应blaTEM-135突变体的阳性率从高至低分别为：浙江（31/45,68.9%）、江苏（14/24,58.3%）、广东（39/78,50.0%）、上海（17/36,47.2%）、天津（9/23,39.1%）、广西（4/12,33.3%）。NG-MAST分型研究显示,blaTEM-135突变体中流行菌株型别有ST2318、ST1768、ST1866、ST1053、ST8726等,其中ST1768、ST1053和ST8726与blaTEM-135突变体有较强的对应关系。天津PPNG菌株及blaTEM-135突变体ST分布与其他各监测点有显著差异,江浙沪地区菌株ST有一定联系。 结论 中国淋球菌耐药监测点PPNG及相应blaTEM-135突变体阳性率处于较高水平,不同地区间PPNG及相应blaTEM-135突变体阳性菌株ST型别分布差异有统计学意义。     

2011-2012年海南地区淋球菌耐药性监测及基因分型研究

【摘要】 目的 探讨海南淋球菌耐药状态及耐药基因分型情况。 方法 用琼脂稀释法测定4种抗生素的最低抑菌浓度（MIC）,PCR方法鉴定四环素高度耐药菌株（TRNG）并进行TetM基因分型;用纸片酸度法测定β内酰胺酶（PPNG）,PCR方法鉴定β内酰胺酶质粒并进行TEM-1基因分型。 结果 2011—2012年共检测214株淋球菌,环丙沙星中度敏感率7.94 %（17/214）,耐药率为92.06%（197/214）;头孢曲松敏感率24.30%（52/214）,中度敏感率为75.70%（162/214）;未发现耐大观霉素的菌株。多重耐药情况：对四环素和青霉素耐药的菌株39株（18.22%）,对青霉素和环丙沙星耐药菌株66株（30.84%）,对四环素和环丙沙星耐药的菌株 91株（42.52%）,对四环素、青霉素和环丙沙星耐药的菌株 37株（17.29%）。检出TRNG 101株（47.20%）,TetM基因分型结果99株（98.02%）荷兰型, 2 株（1.98%）美国型。检出PPNG 65株（30.37%）,TEM-1基因分型结果55株（84.62%）亚州型,10株（15.38%）非州型,未见多伦多型、里约型。 结论 海南省淋球菌对大观霉素敏感率高,应作为治疗淋病的首选药物;多重耐药菌株应引起重视。PPNG以亚州型为主,非州型次之;TRNG以荷兰型为主,偶见美国型。     

Mutation patterns in gyrA and parC genes of ciprofloxacin resistant isolates of Neisseria gonorrhoeae from India

AIM: To analyse mutations in the gyrA and parC genes leading to possible increase in ciprofloxacin resistance (high MIC values for ciprofloxacin) in clinical isolates of Neisseria gonorrhoeae in Delhi, India. METHOD: MIC of ciprofloxacin for 63 clinical isolates of N gonorrhoeae were examined by the Etest method. Subsequently, gyrA and parC genes of these isolates were amplified and sequenced for possible mutations. RESULTS: Out of the 63 clinical isolates tested, only five (8%) isolates were found to be susceptible to ciprofloxacin (MIC <0.06 micro g/ml). DNA sequence analysis of the gyrA and the parC genes of all these isolates (n = 63) revealed that all isolates which were not susceptible to ciprofloxacin (n=58) had mutation(s) in gyrA and parC genes. 12 isolates (19%) exhibited high resistance with an MIC for ciprofloxacin of 32 micro g/ml. Two out of these 12 isolates (UD62 and UD63), harboured triple mutations (Ser-91 to Phe, Asp-95 to Asn and Val-120 to Leu) in the gyrA gene. The third mutation of Val-120 to Leu, lies downstream of the quinolone resistance determining region (QRDR) of the gyrA and has not been described before in gonococcus. In addition, both these isolates had a Phe-100 to Tyr substitution in the parC, a hitherto unknown mutation. CONCLUSIONS: Emergence of ciprofloxacin resistance with high levels of MIC values (up to 32 micro g/ml) in India is alarming. Double and triple mutations in gyrA alone or together in gyrA and parC could be responsible for such a high resistance.     

The epidemiology of ciprofloxacin resistant isolates of Neisseria gonorrhoeae in Scotland 2002: a comparison of phenotypic and genotypic analysis

OBJECTIVES: To characterise all isolates with reduced susceptibility or resistance to ciprofloxacin received by the Scottish Neisseria gonorrhoeae Reference Laboratory (SNGRL) in 2002 using N gonorrhoeae multi-antigen sequence typing (NG-MAST); to compare NG-MAST with conventional typing and to describe the epidemiology of ciprofloxacin resistant gonorrhoea in Scotland in 2002. METHODS: Isolates were characterised on receipt by auxotyping and serotyping (A/S typing), and antibiotic susceptibility testing, and retrospectively by NG-MAST. Epidemiological data were requested for all isolates in the study. RESULTS: The 106 isolates were separated into more sequence types (ST) than A/S classes (44 versus 17). All isolates within a sequence type had the same serotype, were homogeneous with respect to ciprofloxacin resistance category, but were sometimes heterogeneous with respect to auxotype or plasmid borne resistance to penicillin. Combined NG-MAST and epidemiological data revealed sustained transmission of several gonococcal strains predominantly within Greater Glasgow and Lothian. Clusters of isolates were associated with transmission within the United Kingdom, whereas isolates with unique STs were associated with foreign travel (p < 0.0001). CONCLUSIONS: NG-MAST is more discriminatory than A/S typing. Ciprofloxacin resistant gonococcal isolates in Scotland are heterogeneous, with endemic spread of some strains occurring predominantly in Greater Glasgow and Lothian.     

Mutations in the gyrA and parC genes and in vitro activities of fluoroquinolones in 91 clinical isolates of Neisseria gonorrhoeae in Japan

BACKGROUND AND OBJECTIVES: Fluoroquinolone resistance in Neisseria gonorrhoeae has been associated with alternations in the quinolone-resistance determining regions in the gyrA and parC genes. GOAL: The goal of this study was to investigate the correlation between fluoroquinolone minimum inhibitory concentrations (MICs) and mutations in the gyrA and parC genes of 91 N. gonorrhoeae clinical isolates from Japan. STUDY DESIGN: The MICs of fluoroquinolones ciprofloxacin, levofloxacin, and gatifloxacin for 91 clinical isolates from male gonococcal urethritis in Hyogo or Osaka, Japan, were measured, and the gyrA and parC genes of these isolates were sequenced. RESULTS: Among 91 isolates tested, over 70% isolates were resistant to ciprofloxacin. We found that 4 mutations (Ser-91-Phe, Ser-91-Ile, Asp-95-Gly in gyrA, and Ser-88-Pro in parC) had significant correlation to MICs of fluoroquinolone (ciprofloxacin, levofloxacin, and gatifloxacin). CONCLUSION: Some mutations in QRDR had a significant relationship to the fluoroquinolone resistance of N. gonorrhoeae clinical isolates from Japan.     

Susceptibility of gonococci isolated in London to therapeutic antibiotics: establishment of a London surveillance programme. London Gonococcal Working Group

OBJECTIVES: To establish the in vitro susceptibility of gonococci isolated in the London area to antibiotics in current therapeutic use and to establish a sentinel surveillance system for monitoring trends in antibiotic resistant gonorrhoea in London. METHODS: Isolates of Neisseria gonorrhoeae from consecutive patients attending genitourinary medicine clinics at 10 hospitals in the London area were collected over a 3 month period, May to July 1997. The susceptibility to penicillin, ciprofloxacin, tetracycline, and spectinomycin was determined for each isolate. Isolates exhibiting either plasmid or chromosomally mediated resistance were additionally tested for susceptibility to agents used as alternative treatments including azithromycin, ceftriazone, and ofloxacin. The resistant isolates were also tested for plasmid profiles (penicillinase producing N gonorrhoeae, PPNG), type of tetM determinant (tetracycline resistant N gonorrhoeae, TRNG), and presence of gyrA and parC mutations (quinolone resistant N gonorrhoeae, QRNG). RESULTS: A total of 1133 isolates were collected which represents > 95% of the total gonococci isolated in the 3 months. Plasmid mediated resistance was exhibited by 48 (4.2%) isolates; six (0.5%) were PPNG, 15 (1.3%) were PP/TRNG, and 27 (2.4%) were TRNG. The majority of PPNG (18 of 20 tested) carried the 3.2 MDa penicillinase plasmid whereas the two types of tetM determinant were more evenly distributed. High level resistance to ciprofloxacin was detected in four (0.4%) isolates and double mutations were found in the quinolone resistance determining region (QRDR) of the gyrA gene in three QRNG with MICs of 16 mg/l and a single mutation in one isolate with a MIC of 1 mg/l to ciprofloxacin. No parC mutations were found. Of the remaining 1081 isolates, 86 (8.0%) were chromosomally mediated resistant N gonorrhoeae (CMRNG). CONCLUSIONS: A unique collection of gonococcal isolates has been established which can be used as a baseline for surveillance of susceptibility to antibiotics and for epidemiological purposes.     

Antimicrobial resistance patterns (1999-2002) and characterization of ciprofloxacin-resistant Neisseria gonorrhoeae in Korea

BACKGROUND: Antimicrobial susceptibilities of Neisseria gonorrhoeae were monitored during 4 years. In Korea, ciprofloxacin-resistant N. gonorrhoeae has dramatically increased after recommendation as a therapeutic drug. GOAL: The goal of this study was to determine the resistance patterns and characterize Korean ciprofloxacin-resistant N. gonorrhoeae. STUDY DESIGN: Antimicrobial susceptibilities were performed. PFGE profile and DNA sequencing of gyrA and parC genes were used to characterize the ciprofloxacin-resistant isolates in Korea. RESULTS: Tetracycline, ofloxacin, ciprofloxacin-resistant isolates were increased and among them, the proportion of isolates resistant to ciprofloxacin increased remarkably from 1% in 1999 to 48.8% in 2002. Fifteen different types by PFGE profile were identified. Major alteration type was M12 (67%), which have amino acid substitution in gyrA (S-91-->F, D-95-->G) and parC (S-87-->A). CONCLUSION: We could conclude that resistance for ciprofloxacin was remarkably increased during 4 years. Ciprofloxacin-resistant N. gonorrhoeae was supposed by the spread of several strains that had a small number of origins.     

High occurrence of simultaneous mutations in target enzymes and MtrRCDE efflux system in quinolone-resistant Neisseria gonorrhoeae

BACKGROUND: Emergence of multidrug-resistant Neisseria gonorrhoeae resulting from new genetic mutations is a serious threat to controlling gonorrhea. GOAL: To determine 1) antimicrobial susceptibilities and the corresponding genetic mutations and 2) the role of MtrRCDE efflux system in gonococcal resistance to fluoroquinolones. STUDY DESIGN: Antimicrobial susceptibility testing and sequence analysis of gyrA, parC, and mtrR loci of 131 N. gonorrhoeae isolates from Japan. RESULTS: The proportion of N. gonorrhoeae strains resistant and intermediate-resistant to antimicrobials was 25.2% and 48.9% for ciprofloxacin, 25.2% and 30.5% for ofloxacin, 12.2% and 53.4% for penicillin; and 17.6% and 51.1% for tetracycline, respectively. Strains were categorized into 22 mutation profiles, with GyrA-S91F/ParC-D86N/MtrR-G45D being the most predominant profile. The frequency of mutation in gyrA, parC, mtrR, and the mtrR promoter was 71%, 47.3%, 77.1%, and 23.7%, respectively. Seventy-one percent of strains carried mutations in both gyrA and mtrR. CONCLUSION: This study reports simultaneous mutations in fluoroquinolone target enzymes and the MtrRCDE efflux system as a fluoroquinolone-resistant mechanism in N. gonorrhoeae.     

1999-2006年南京地区淋球菌对环丙沙星耐药现状的分析

目的 了解南京地区1999-2006年淋球菌对环丙沙星的耐药现状.方法 对1999-2006年在南京地区性病门诊患者中分离到的1208株淋球菌,采用琼脂稀释法测定环丙沙星的最小抑菌浓度(MIC).结果 对环丙沙星耐药(MIC 1mg/L)的淋球菌率由1999年的83.93%(94/112)上升至2006年的98.99%(196/198),平均总耐药率为96.61%(1167/1208).其中环丙沙星高度耐药(MIC≥4mg/L)的淋球菌比率达71.61%(865/1208).结论 南京地区流行的淋球菌对环丙沙星的耐药情况极其严重.     

Characterization of ciprofloxacin resistance in Neisseria gonorrhoeae isolates in Canada

BACKGROUND: Ciprofloxacin (500 mg orally, single dose) is one of the recommended therapies for gonorrhea in Canada. In Canada, the first ciprofloxacin-resistant (CipR) Neisseria gonorrhoeae strain was isolated in 1993. Antimicrobial susceptibilities of N gonorrhoeae isolates were monitored as part of a national surveillance program to ensure efficacy of antimicrobial therapies. GOAL: The goal was to determine the characteristics of ciprofloxacin resistance in Canadian gonococcal isolates. STUDY DESIGN: Susceptibility testing was performed on gonococcal strains from different provinces in Canada to determine the prevalence of CipR strains and their distribution. The CipR strains were further differentiated according to auxotype (A), serotype (S), plasmid profile (P), and pulsed-field gel electrophoresis (PFGE) profile. DNA sequencing and DNA microarray technology were used to determine mutations in gyrA and parC. RESULTS: In Canada, between 1997 and 1999, 4.8% of resistant strains (130 of 2687 antibiotic-resistant N gonorrhoeae isolates) were CipR (MICs of 1-32 microg/l) and belonged to 48 A/S/P classes. Sixty-eight of the strains that were not differentiated by A/S/P were subtyped into 47 classes with PFGE. DNA sequencing and DNA microarray showed that the most common mutations had amino acid substitutions of Ser-->Phe at codon 91 and Asp-->Gly at codon 95 of the gyrA and Ser-->Arg at codon 87 of parC. CONCLUSION: The CipR strains isolated in Canada are phenotypically and genotypically diverse, indicating that they were imported from overseas and not endemic in Canada. Mutations in gyrA and parC previously only identified by DNA sequencing were successfully identified with DNA microarray technology. DNA microarray technology could be an alternative tool for identifying point mutations in resistance genes or other epidemiologic markers when clinical laboratories replace culture methods with rapid and automated molecular methods for diagnosis.     

Molecular characterization of ciprofloxacin resistance of gonococcal strains in Spain

BACKGROUND: Over the past several years, the emergence of gonococcal isolates with intermediate or full resistance to fluoroquinolones has become a significant concern in several countries, including Spain. GOAL: The goal was to determine the occurrence of ciprofloxacin resistance among Neisseria gonorrhoeae strains in Spain during 2000 to 2001 and determine the frequency and patterns of mutations at gyrA, gyrB, and parC genes in these isolates. STUDY DESIGN: Eleven ciprofloxacin-resistant strains (with MICs ranging from 1 to 64 micrograms/mL) and two intermediate isolates (with MICs of 0.12 and 0.5 microgram/mL) were found. Mutations were identified by polymerase chain reaction and direct sequencing of the amplified products. RESULTS AND CONCLUSIONS: Alterations at Ser-91 and Asp-95 in GyrA were detected in all strains except one, an isolate for which the MIC was 0.12 microgram/mL. Alterations in ParC were more variable, and there was no clear correlation between the number of parC mutations and the level of resistance. No alterations at gyrB gene associated with ciprofloxacin resistance were found. The resistance was distributed among different types of strains, suggesting that the increase in the incidence of ciprofloxacin-resistant strains in Spain was not exclusively due to the appearance of a single-strain outbreak.