| Objective:(1)To study the prevalence and distribution characteristics of the Neisseria gonorrhoeae and Mycoplasma among visitors to STDs clinics in Jiangsu Province, as well as to investigate the risk factors associated with Neisseria gonorrhoeae and Mycoplasma infection. (2) To describe the resistance of the strains to the antibiotics used for treating the infections. (3)To make clear the prevalence of resistance genes among the strains. Methods: (1)Specimens from visitors were inoculated directly onto T-M selective medium for culture and incubated at 35℃ in an atmospere containing 4%~6% CO2 for 36~48hrs. Neisseria gonorrhoeae were presumptively identified on the basis of colonial and Gram's stain morphology and positive oxidase reaction, then identity was confirmed by using API identification system.The identification and susceptibility test of mycoplasma strains was conducted by the Mycoplasma ISTⅡkit. Combining with the epidemiology data, χ2 test and Fisher's exact test were used for comparison, and Logistic regression for finding risk factors. (2)95 strains of Neisseria gonorrhoeae were randomly selected from 125 isolates to perform the in-vitro susceptibility test. MICs of penicillin, tetracycline, ciprofloxacin, levofloxacin, ceftriaxone, cefotaxime, cefepime, spectinomycin were determined by agar dilution using GC agar base containing 1% defined supplement and serial dilutions of each agent. (3)48 strains were randomly selected from those mentioned in the susceptibility testing to amplify the TEM and tetM gene, among which, 20 strains' gyrA gene was sequenced and compared with the sequence of ATCC19424 by DNAStar software. 16S rRNA was amplified and analyzed for the spectinomycin resistant strain and sensitive one by the same method.Results:(1)Among the visitors to STDs clinics in Jiangsu province, the prevalence of Neisseria gonorrhoeae and Ureaplasma urealyticum and/or Mycoplasma hominis were 23.3% and 28.9% respectively. The prevalence of Neisseria gonorrhoeae has significant differences between Nanjing, Xuzhou and Wuxi. The same difference was found between male and female. The prevalence of Neisseria gonorrhoeae among the visitors in Xuzhou was lower than Nanjing and Xuzhou. The infection rate among male was higher than female. The infection rate of Ureaplasma urealyticum and/or Mycoplasma hominis among female was higher than male. (2)The prevalence of Neisseria gonorrhoeae is significantly associated with gender, recent sexual contact with persons other than their own partners and the group whose partners were diagnosed with sexually transmitted diseases, while the prevalence of mycoplasma is significantly associated with female and young individuals aged less than 25y.(3)Almost all of the Neisseria gonorrhoeae strains were susceptible to the first-line antibiotics used for treating the infection. The resistance rate to ciprofloxacin, tetracycline and penicillin were 100%, 78.9% and 68.4% respectively. Most of Ureaplasma urealyticum and/or Mycoplasma hominis were sensitive to pristinamycine, josamycin and doxycycline. But most of them are resistant to ciprofloxacin and ofloxacin. The sensitive rate of Ureaplasma urealyticum to azithromycin, clarythromycin, erythromycin are all up to 88%, but Mycoplasma hominis are totally different.(4)TEM seems to be more frequent in PPNG than non-PPNG and tetM seems to be more frequent in TRNG than non-TRNG. 20 strains of Neisseria gonorrhoeae which are intermediate resistant and resistant to ciprofloxacin have been associated with mutations in the gyrA protein of the DNA gyrase. There are four types of alteration in the gyrA: a serine-to-phenylalanine substitution at position 91 and aspartate-to-glycine at position 95; a serine-to-phenylalanine substitution at position 91 and aspartate-to-alanine at position 95; a serine-to-phenylalanine substitution at position 91 and aspartate-to-asparagine substitution at position95; a serine-to-phenylalanine substitution at position 91 and alanine-to-proline at position 92. The strain resistant to spectinomycin is...
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