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目的:分析皮肤化脓性感染部位分离的金黄色葡萄球菌(简称金葡菌)耐药、毒力及分子流行病学特征,为临床抗感染用药提供实验依据。方法:收集内蒙古医科大学附属医院2020年5-12月皮肤科住院患者皮肤化脓性感染部位及鼻腔分泌物样本进行细菌分离培养。采用基质辅助激光解吸电离飞行时间质谱鉴定疑似金葡菌菌落,用微量肉汤稀释法进行药物敏感性试验,PCR扩增金葡菌毒力基因,实时荧光定量PCR检测tsst-1、pvl、hla、clfA 4种毒力基因在不同来源金葡菌菌株中的相对表达量。对金葡菌菌株进行多位点序列分型(MLST)。耐药率及毒力基因检出率比较采用n χ2检验或Fisher确切概率法,计量资料组间比较采用n t检验或曼-惠特尼n U非参数检验。n 结果:在210例住院患者中,共分离金葡菌85株,包括皮肤化脓性感染部位54株(病例组),鼻腔部位31株(对照组)。药敏试验结果显示,85株金葡菌中14株为耐甲氧西林金葡菌(MRSA)。85株菌对青霉素耐药率[90.59%(77/85)]最高;对克林霉素和红霉素耐药率分别为60.00%(51/85)、61.18%(52/85),未发现对利福平、万古霉素和利奈唑胺耐药菌株。PCR显示,病例组菌株pvl基因检出率(33.33%,18/54)高于对照组(12.90%,4/31,n χ2 = 4.28,n P = 0.038)。实时荧光定量PCR显示,对照组菌株clfA相对表达量[3.87(2.30,5.94)]高于病例组[1.63(0.95,2.62),n P = 0.007]。85株金葡菌分型共得到17个ST型别,其中主要优势型别为ST398-甲氧西林敏感金葡菌(20/71)和ST22-MRSA(9/14)。ST22-MRSA菌株毒力基因pvl检出率(14/14)明显高于非ST22型MRSA(0,n P < 0.001)。n 结论:皮肤化脓性感染部位分离的金葡菌对青霉素、克林霉素和红霉素耐药率较高,这些抗生素不应作为临床经验治疗的首选药;皮肤金葡菌感染性疾病发病可能与毒力基因pvl有关;金葡菌鼻腔定植可能与clfA基因有关。“,”Objective:To analyze drug resistance, virulence and molecular epidemiological characteristics of n Staphylococcus aureus (n S. aureus) isolated from skin sites of suppurative infections, and to provide an experimental basis for clinical anti-infective therapies.n Methods:Swab samples from suppurative skin lesions and nasal secretions were collected from inpatients in Department of Dermatology, the Affiliated Hospital of Inner Mongolia Medical University from May 2020 to December 2020, and subjected to bacterial isolation and culture. Suspected n S. aureus colonies were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Drug sensitivity test was conducted by using the broth microdilution method. Virulence genes of n S. aureus were amplified by PCR, and real-time fluorescence-based quantitative PCR was performed to determine the relative expression of 4 virulence genes including tsst-1, pvl, hla and clfA in n S. aureus strains from different sources. n S. aureus strains were genotyped by multilocus sequence typing. Drug resistance rates and detection rates of virulence genes were compared by using chi-square test or Fisher′s exact test, and measurement data among groups were compared by using n t test or Mann-Whitney n U test.n Results:A total of 85 strains of n S. aureus were isolated from 210 inpatients, including 54 isolates from skin sites of suppurative infections (case group) and 31 isolates from the nasal cavity (control group) . Drug sensitivity test showed that 14 strains of methicillin-resistant n S. aureus (MRSA) were identified among 85 strains of n S. aureus. The resistance rate to penicillin was the highest (90.59%, 77/85) in the 85 n S. aureus strains; the resistance rates to clindamycin and erythromycin were 60.00% (51/85) and 61.18% (52/85) respectively; no strains showed resistance to rifampicin, vancomycin or linezolid. PCR showed that the detection rate of the pvl gene was 33.33% (18/54) in the case group, which was significantly higher than that in the control group (12.90%, 4/31; n χ2= 4.28, n P= 0.038) . Real-time fluorescence-based quantitative PCR showed that the relative expression level of the clfA gene was significantly higher in the control group (3.87[2.30, 5.94]) than in the case group (1.63[0.95, 2.62],n P= 0.007) . A total of 17 ST types were identified among the 85 strains of n S. aureus, and the dominant types were ST398-methicillin-susceptible n S. aureus (20/71) and ST22-MRSA (9/14) . The detection rate of the virulence gene pvl was significantly higher in the ST22-MRSA strain (14/14) than in the non-ST22 MRSA strains (0, n P < 0.001) .n Conclusions:S. aureus strains isolated from the skin sites of suppurative infections were highly resistant to penicillin, clindamycin and erythromycin, so these antibiotics should not be used as the first-choice empiric treatment. The occurrence of cutaneous n S. aureus infections may be associated with the virulence gene pvl, and the nasal colonization of n S. aureus may be associated with the clfA gene.n