571例皮肤软组织感染住院患者病原菌分布和耐药性分析

目的:研究我院住院患者中皮肤软组织感染者(SSTI)病原菌分布及耐药性。方法:收集571例我院2018年1月1日至2020年12月31日SSTI病原培养结果阳性的住院患者,分析病原菌分布特点以及主要革兰氏阳性优势菌的耐药情况。结果:患者按病种分类,主要有天疱疮、大疱性类天疱疮、湿疹、银屑病等。571例SSTI患者共培养菌株624株,革兰氏阳性菌529株(占84.8%),革兰氏阴性菌76株(占12.1%),真菌19株(占3.0%);主要优势菌为金黄色葡萄球菌、溶血葡萄球菌、中间葡萄球菌,均对青霉素、红霉素、阿奇霉素明显耐药,对米诺环素和替考拉宁敏感性均为100%。结论:金黄色葡萄球菌、溶血葡萄球菌、中间葡萄球菌为我院SSTI最主要致病菌。革兰氏阳性优势菌对青霉素、红霉素、阿奇霉素等耐药率高,对米诺环素、多西环素、替考拉宁、利奈唑胺等耐药率较低,可以指导临床用药。     

2003～2006年南京地区淋球菌分离株抗菌药物敏感性监测

目的：分析2003～2006年淋球菌耐药现状。方法：纸片酸度定量法测定菌株的β-内酰胺酶;琼脂稀释法测定青霉素、四环素、环丙沙星、大观霉素和头孢曲松对淋球菌的最小抑菌浓度（MIC）。结果：共检测了791株淋球菌,产青霉素酶淋球菌（PPNG）的阳性率每年维持在42.23%～57.36%之间,质粒介导的耐四环素淋球菌（TRNG）的阳性率由2003年的19.47%（37/190）上升到2006年的32.82%（65/198）。在非PPNG中,染色体介导的青霉素耐药菌株的阳性率介于57.84%～87.27%。耐环丙沙星淋球菌的阳性率介于97.89%～99.51%,未检出头孢曲松耐药菌株,每年的低敏菌株比例处于30.58%～57.89%之间。每年均检出1～2株大观霉素耐药菌株,共6株。结论：头孢曲松和大观霉素为治疗淋病的有效药物。     

广西地区淋病患者淋病奈瑟菌对七种抗生素的耐药监测

目的分析2013-2016年广西地区性病门诊淋病患者临床分离菌株对常见的七种抗生素的敏感性。方法从广西地区部分医疗机构淋病患者尿道或宫颈收集分泌物培养,通过纸片酸度定量法测定β内酰胺酶,琼脂稀释法测定青霉素、头孢曲松、头孢克肟、大观霉素、环丙沙星、阿奇霉素和四环素的最小抑菌浓度(MIC)。结果 2013-2016年从淋病患者中共收集临床分离菌株437株,未发现头孢曲松、头孢克肟和大观霉素的耐药菌株。有427株(97.71%)菌株和372株(85.13%)菌株分别对环丙沙星和青霉素耐药。耐四环素淋球菌(TRNG)菌株和β内酰胺酶阳性菌株(PPNG)阳性菌株分别为191株(43.71%)和145株(33.18%)。淋球菌对阿奇霉素耐药率保持1%~8%的较低水平。TRNG菌株和PPNG菌株阳性率均呈上升趋势。结论 2013-2016年期间来自广西地区性病门诊淋病患者的菌株对大观霉素、头孢曲松和头孢克肟敏感,适合作为本地区治疗淋病患者的一线药物;对阿奇霉素有一定耐药,对环丙沙星和青霉素高度耐药,TRNG菌株和PPNG菌株逐年上升,可能与青霉素和四环素的滥用或不规则使用有关。     

葡萄球菌性烫伤样皮肤综合征的致病金黄色葡萄球菌剥脱毒素基因型及耐药研究

目的 探讨葡萄球菌性烫伤样皮肤综合征（SSSS）致病的金黄色葡萄球菌（简称金葡菌）分泌表皮剥脱毒素（ET）的主要类型及耐药情况。方法 108株金葡菌分离自SSSS（36例）、脓疱疮（36例）及皮肤脓肿（36例）。用多重PCR法测定致病金葡菌菌株产ETA、ETB、ETD基因型，Kirby-Bauer纸片法检测其对20种抗生素的敏感性。结果 36株来源于SSSS的金葡菌 100％ （36/36）为产ET菌株，其中单产ETA 2株（6％），ETB 7株（19％），兼产ETA和ETB 27株（75％）。来源于脓疱疮的36株金葡菌78％ （28/36）为产ET菌株，单产ETA 5株（14％），兼产ETA和ETB 23株（64％），未发现单产ETB金葡菌。而分离自皮肤脓肿的36株金葡菌仅2.8%（1/36）产ET，为兼产ETA和ETB菌株。108株金葡菌均未检测到ETD。金葡菌产ET的型别分布在三组疾病间差异有统计学意义（χ2 = 89.4，P ＜ 0.01），且分离自SSSS的金葡菌株产ET的比例明显高于脓疱疮组（χ2 = 9.0，P < 0.01）和脓肿组（χ2 = 68.1，P < 0.01）。三组病例的致病金葡菌对青霉素、氨苄西林、大环内酯类及克林霉素高度耐药，但对头孢类抗生素均敏感。脓肿组发现2例耐甲氧西林金葡菌株（MRSA）。结论 SSSS及脓疱疮患儿的致病金葡菌主要为产ET菌株，并以兼产ETA和ETB菌株为主。     

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。     

解脲脲原体对红霉素耐药机制的初步研究

目的 探讨解脲脲原体对红霉素的耐药机制。方法 对73株从泌尿生殖道分离的解脲脲原体进行体外药物敏感试验筛选耐药菌株,并设立临床敏感菌株组以及标准菌株对照组,用PCR测序法检测23SrRNA的V区热点突变以及特异性引物PCR检测甲基化酶（ermA、ermB、ermC）、主动外排泵（mefA/E、msrA/B、mreA）等可转移耐药基因。结果 73株临床菌株中,耐药菌株35株（47.95%）,耐药菌株MIC范围为8 ~ 32 mg/L。在耐药菌株组发现ermB耐药基因（19株,占54.29%）和msrA/B耐药基因（9株,占25.71%）的阳性扩增,其中有2株（占5.71%）同时存在ermB基因和msrA/B基因阳性扩增,ermB基因和msrA/B基因的阳性扩增比率差异有统计学意义（P < 0.05）。临床敏感菌株组及标准菌株组均未发现23SrRNA的V区点突变及可转移耐药基因的阳性扩增。结论 ermB甲基化酶基因和msrA/B外派泵基因可能是导致解脲脲原体对红霉素耐药原因之一。     

淋球菌青霉素结合蛋白PPNG基因与耐青霉素类药物的关系

目的　探讨淋球菌青霉素结合蛋白 2基因 (PenA)突变及产青霉素酶淋球菌 (PPNG)与耐青霉素类药物的关系。方法　采用巢式聚合酶链技术对 97株淋球菌临床分离株进行PPNG基因检测 ,并对 4例PPNG基因检测阴性、而抗生素药敏试验表明对青霉素类药物耐药的淋球菌菌株的PenA基因进行测序。结果　 97株淋球菌菌株中有 67株为PPNG基因检测阳性 ;而 4株PPNG阴性的耐药菌株的PenA基因序列均存在点突变。结论　PPNG所导致的耐药是淋球菌耐青霉素类药物的主要来源 ;PenA基因突变是产生耐药菌株的主要原因。     

100株淋球菌对7种抗生素的耐药性结果分析

 目的:监测2019年本单位淋球菌对7种抗生素的耐药性趋势及产青霉素酶淋球菌(PPNG)和质粒介导的高度耐四环素淋球菌(TRNG)流行情况,为临床有效选择抗生素提供实验室依据。方法：收集本单位门诊临床分离培养的100株淋球菌,用琼脂稀释法测定青霉素、四环素、环丙沙星、大观霉素、阿奇霉素、头孢曲松、头孢克肟的最低抑菌浓度（MIC）;用纸片碘量法检测β 内酰胺酶。结果：产青霉素酶淋球菌（PPNG）株占35％（35/100）,质粒介导的高度耐四环素淋球菌（TRNG）株占32％（32/100）。环丙沙星和青霉素的耐药率分别高达99％（99/100）、93%（93/100）。阿奇霉素耐药率达10%（10/100）。头孢曲松和头孢克肟未见耐药菌株,低敏率分别为22%（22/100）和19%（19/100）,敏感率分别为78%（78/100）和81%（81/100）。大观霉素未发现耐药菌株和低敏菌株。结论：头孢曲松、头孢克肟、大观霉素仍可推荐为广州地区淋病患者首选药物。建议临床制定合理抗菌治疗方案以提供科学指导时,应长期监测淋球菌耐药性。     

抗信号识别颗粒抗体阳性的皮肌炎/临床无肌病性皮肌炎患者临床特点分析

【摘要】 目的 分析血清抗信号识别颗粒（SRP）抗体阳性的皮肌炎/临床无肌病性皮肌炎（DM/CADM）患者的临床特点。方法 收集2015年6月至2017年7月上海交通大学医学院附属瑞金医院皮肤科病房收治的90例DM/CADM患者的临床资料,用免疫印迹法检测患者血清抗SRP抗体。采用t检验和χ2检验等方法进行统计学分析。结果 90例DM/CADM患者中11例（12.2%）血清抗SRP抗体阳性,其中6例DM,5例CADM。82例成人DM/CADM患者中,抗SRP抗体阳性合并恶性肿瘤的发生率显著高于抗SRP抗体阴性患者［7/9比31.5%（23/73）,χ2 = 7.394,P = 0.006］。11例抗SRP抗体阳性患者均有DM典型皮疹,DM皮损面积和严重指数为18.1 ± 2.9。抗SRP抗体阳性患者翼状征的发生率显著高于抗体阴性患者［7/11比29.9%（20/67）,Fisher精确检验,P = 0.028］。抗SRP抗体阳性患者抗核抗体阳性率显著高于抗体阴性患者［4/8比16.7%（13/78）,χ2 = 6.053,P = 0.014］。10例抗SRP抗体阳性患者（6例DM和4例CADM）行双大腿肌肉磁共振检查,其中8例肌群内信号异常,肌群肿胀2例,皮下水肿2例,肌筋膜肿胀1例,仅2例无异常。抗SRP抗体阳性患者均无肺间质病变和心肌受累。结论 抗SRP抗体阳性DM/CADM患者躯干翼状征发生率高,合并恶性肿瘤的风险显著增加。DM/CADM患者在病程早期检测抗SRP抗体水平有助于预测恶性肿瘤的发生。     

淋球菌耐药监测的流行病学研究

对临床分离的淋球菌进行系统鉴定后,用琼脂稀释法测定最低抑菌浓度(MIC)及纸片酸度定量法测定β-内酰胺酶,数据处理采用SPSS软件进行分析.结果:529株淋球菌中检出PPNG阳性59株(11.15%),TRNG阳性304株(57.47%),对环丙沙星、头孢曲松和大观霉素的耐药率分别为89.41%、0.38%和0;耐药相关性表明,TRNG阳性率和CIP耐药率呈正相关,CRO耐药的2株菌均为TRNG阳性菌株,多重耐药菌株比例相当高,占55.01%.在南宁地区,环丙沙星、青霉素和四环素已不适用于治疗淋病,大观霉素和头孢曲松仍是首选.     

2018-2020年皮肤科住院患者金黄色葡萄球菌感染状况及MRSA与MSSA耐药性分析

目的:研究我院住院患者中皮肤软组织感染者(SSTIs)金黄色葡萄球(SA)感染情况及MR-SA与MSSA耐药特点.方法:选取我院2018年1月1日至2020年12月31日入院时存在SSTIs且进行细菌培养及药敏试验的患者,分析SA及MRSA检出率、病种分布,以及MRSA与MSSA耐药性的差异.结果:共分析1455例患者...     

武汉市丙酸杆菌对红霉素耐药与23S rRNA点突变和携带erm基因相关

目的 探讨武汉市耐红霉素丙酸杆菌23S rRNA 有无点突变以及携带ermX基因的Tn5432转座子是否转入了丙酸杆菌。 方法 从痤疮患者皮损中分离丙酸杆菌,E-test法检测分离株对红霉素和克林霉素的MIC值。PCR扩增耐药株23S rRNA、ermX、ermX（cj）、IS1249a、IS1249b并测序,并在基因库中比较。 结果 19株痤疮丙酸杆菌（P.acnes）和10株卵白丙酸杆菌（P.avidum）对红霉素均表现为高度耐药（MIC均 > 256 μg/ml）。19株P.acnes中,16株对克林霉素高度耐药（MIC > 256 μg/ml）,3株敏感;10株P.avidum对克林霉素高度耐药（MIC > 256 μg/ml）。19株P.acnes耐药株中,7株在相当于E.coli 23S rRNA 2058位点发现由A→G点突变,均对红霉素和克林霉素高度耐药;4株在相当于E.coli 23S rRNA 2059位点发现由A→G点突变,其中1株对克林霉素耐药,3株敏感;另外8株P.acnes扩增ermX阳性,其序列与基因库中P.acnes ermX基因100%同源。10株P.avidum中,2株ermX扩增阳性,其序列与P.acnes ermX基因100%同源;另外8株扩增ermX（cj）得到预期片段PCR产物,与基因库中Corynebacterium jeikeium ermX（cj）序列99%同源,而与P.acnes ermX基因仅有94%的同源性。10株扩增ermX基因阳性的菌株扩增IS1249a和IS1249b均阳性,而其余菌株均阴性。 结论 武汉市耐红霉素丙酸杆菌分别由相当于E.coli 23S rRNA 2058、2059由A→G点突变、携带ermX的Tn5432传入以及ermX（cj）传入丙酸杆菌引起。     

Antimicrobial susceptibility of Staphylococcus aureus isolated from children with impetigo in China from 2003 to 2007 shows community‐associated methicillin‐resistant Staphylococcus aureus to be uncommon and heterogeneous

Background The number of patients with impetigo caused by community‐associated methicillin‐resistant Staphylococcus aureus (CA‐MRSA) has been increasing. Objectives To investigate the antimicrobial susceptibility of S. aureus causing impetigo in children in China from 2003 to 2007 and further characterize isolates of CA‐MRSA. Materials and methods We examined 984 S. aureus isolates for antimicrobial susceptibility to 11 antimicrobials using the agar dilution method. CA‐MRSA isolates were analysed for Panton–Valentine leucocidin (PVL) genes, and staphylococcal cassette chromosome mec (SCCmec) typing was performed. Results The largest proportion (94·5%) of strains were resistant to penicillin, followed by erythromycin (86·2%) and clindamycin (69·6%). In total 772 of 984 (78·5%) S. aureus strains were multiresistant. The incidence of CA‐MRSA was 1·1%, with a high rate of resistance to clindamycin (90·9%) and tetracycline (72·7%), but all were susceptible to ciprofloxacin. The susceptibility profiles of MRSA to other antimicrobial agents were similar to those of methicillin‐sensitive S. aureus (MSSA). None of the S. aureus strains were resistant to vancomycin and fusidic acid; moreover, only one strain was resistant to mupirocin. Typing of the SCCmec showed that 54·5% were type IV, 18·2% were type V and 9·1% were type VI. All the PVL‐positive CA‐MRSA carried SCCmec type IV. Conclusions CA‐MRSA is still relatively uncommon and heterogeneous in children in China. Penicillin and erythromycin are no longer appropriate agents. Effective antibiotic agents for patients with impetigo are mupirocin and fusidic acid.     

Current status of Panton–Valentine leukocidin-positive methicillin-resistant Staphylococcus aureus isolated from patients with skin and soft tissue infections in Japan

The USA300 clone, which produces Panton–Valentine leukocidin (PVL), is a major pathogenic community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) clone that causes intractable skin infections. Recently, PVL-positive CA-MRSA, including USA300 clones, have emerged in both communities and hospitals in Japan. To prevent an outbreak of PVL-positive MRSA, infected patients should be treated with effective antimicrobial agents at community clinics. Herein, we investigate molecular epidemiological characteristics of PVL-positive MRSA isolated from outpatients with skin and soft tissue infections (SSTI), which are common community-onset infectious diseases. The detection rate of MRSA was 24.9% (362 strains) out of 1455 S. aureus strains isolated between 2013 and 2017. Among the MRSA strains, 15.5% (56 strains) were PVL-positive strains and associated with deep-seated skin infections. Molecular epidemiological analyses of PVL-positive MRSA showed that USA300 was the predominant clone (53.6%, 30 strains) and was identified in Kanto (18 strains), Kagawa (nine strains), Tohoku (two strains) and Hokkaido (one strain). Notably, minocycline and fusidic acid were effective against all PVL-positive MRSA strains. Hence, our data reveals the current status of PVL-positive MRSA isolated from patients with SSTI in Japan. Continuous surveillance of CA-MRSA is necessary to monitor latest prevalence rates and identify effective antimicrobial agents for PVL-positive MRSA strains.     

Antimicrobial susceptibility of Propionibacterium acnes isolates from acne patients in Colombia

Background The increasing prevalence of antimicrobial resistance in Propionibacterium acnes poses a significant challenge to successful treatment outcomes in acne patients. Although P. acnes resistance has been demonstrated throughout the world, no previous data regarding the antimicrobial susceptibility of P. acnes in Colombia are available. Objectives The aim of this study was to determine the antimicrobial susceptibility of P.  acnes to common antibiotics used in the treatment of acne in a Colombian population. Methods Samples were collected from facial acne lesions of 100 dermatology patients. All samples were cultured in anaerobic conditions, and final identification of isolates was performed. Isolates of P. acnes were then subjected to antimicrobial susceptibility tests using erythromycin, clindamycin, tetracycline, doxycycline, and minocycline. Results Propionibacterium acnes isolates resistant to erythromycin (35%), clindamycin (15%), doxycycline (9%), tetracycline (8%), and minocycline (1%) were observed. Isolates with cross‐resistance were also observed (to erythromycin and clindamycin [12%] and to doxycycline and tetracycline [6%]). Overall, 46% of isolates taken from patients with a history of antibiotic use demonstrated resistance, whereas 29% of isolates taken from patients who had never used antibiotics demonstrated resistance. Conclusions Antimicrobial resistance in P. acnes in this Colombian population has a lower prevalence than those reported in Europe and follows a similar pattern to findings elsewhere in Latin America. Resistance is demonstrated even in isolates from patients with no previous history of antibiotic use. Resistance to erythromycin is most commonly observed. Minocycline emerges as the most effective antibiotic.     

Phenotypic and genotypic characterization of antibiotic-resistant Propionibacterium acnes isolated from acne patients attending dermatology clinics in Europe, the U.S.A., Japan and Australia

BACKGROUND: Propionibacterium acnes is the target of antimicrobial treatments for acne vulgaris. Acquired resistance to erythromycin, clindamycin and tetracyclines has been reported in strains from diverse geographical loci, but the molecular basis of resistance, via mutations in genes encoding 23S and 16S rRNA, respectively, has so far only been elucidated for isolates from the U.K. OBJECTIVES: To determine whether similar or different resistance mechanisms occur in resistant P. acnes isolates from outside the U.K. METHODS: The phenotypes and genotypes of 73 antibiotic-resistant strains of P. acnes obtained from the skin of acne patients in the U.K., U.S.A., France, Germany, Australia and Japan were compared. Antibiotic susceptibilities were determined by minimum inhibitory concentration (MIC) measurements, and polymerase chain reaction and DNA sequencing were used to identify mutations in genes encoding rRNA. RESULTS: Most erythromycin-resistant isolates (MIC(90) > or = 512 microg mL(-1)) were cross-resistant to clindamycin but at a much lower level (MIC(90) > or = 64 microg mL(-1)). As in the U.K., resistance to erythromycin was associated with point mutations in 23S rRNA in 49 of 58 strains. An A-->G transition at Escherichia coli equivalent base 2058 was present in 24 strains. This gave a unique cross-resistance phenotype against a panel of macrolide, lincosamide and type B streptogramin antibiotics. Two further point mutations (at E. coli equivalent bases 2057 and 2059) were identified (in three and 22 isolates, respectively) and these were also associated with specific cross-resistance patterns originally identified in isolates from the U.K. However, nine of 10 erythromycin resistant-strains from Germany did not exhibit any of the three base mutations identified and, in six cases, cross-resistance patterns were atypical. Consistent with previous U.K. data, 34 of 38 tetracycline-resistant strains carried a base mutation at E. coli 16S rRNA equivalent base 1058. Tetracycline-resistant isolates displayed varying degrees of cross-resistance to doxycycline and minocycline, but isolates from the U.S.A. had higher MICs for minocycline (4--16 microg mL(-1)) than isolates from other countries and, in particular, Australia. All the P. acnes isolates resistant to one or more of the commonly used antiacne antibiotics were sensitive to penicillin, fusidic acid, chloramphenicol and the fluoroquinolone, nadifloxacin. All but one isolate (from the U.K.) were sensitive to trimethoprim. CONCLUSIONS: This study shows that 23S and 16S mutations identified in the U.K. conferring antibiotic resistance in P. acnes are distributed widely. However, resistant strains were isolated in which mutations could not be identified, suggesting that as yet uncharacterized resistance mechanisms have evolved. This is the first report of high-level resistance to minocycline and is of concern as these strains are predicted to be clinically resistant and are unlikely to remain confined to the U.S.A. Epidemiological studies are urgently required to monitor how resistant strains are selected, how they spread and to ascertain whether the prevalence of resistance correlates with antibiotic usage patterns in the different countries.     

Panton-Valentine Leukozidin in chronischen Wunden

Background

The toxin Panton-Valentine leukocidin (PVL) produced by S. aureus is known as a virulence factor that leads to severe infections of skin and soft tissue. However the effect of PVL on wound healing is not known yet. Therefore we examined the detection rate of PVL in patients with chronic wounds.

Patients and methods

The study included 100 patients with chronic wounds of the lower limb. We determined in all S. aureus isolates the presence of the PVL gene using a PCR technique.

Results

Altogether 94?% of the patients had a leg ulcer, while 6?% had a foot ulcer; 65?% were women. PVL was found in two patients. One of the strains was methicillin-resistant (MRSA) and the other was methicillin-sensitive (MSSA).

Conclusion

In our investigation there was detection rate for PVL of 2?% of all S. aureus isolates in patients with chronic wounds of the lower extremities. Although the role of PVL as a virulence factor of S. aureus in wound healing remains unclear, the detection of PVL should be taken as a cause for a consequent topical antimicrobial wound therapy because of the increased risk of serious infections.     

Auxotype/serovar diversity and antimicrobial resistance of Neisseria gonorrhoeae in two mid-sized American cities

To characterize the prevalence and heterogeneity of Neisseria gonorrhoeae with chromosomally mediated resistance to penicillin G or tetracycline.HCl in Seattle, Washington, and Denver, Colorado, we auxotyped, serotyped, and determined the MICs of penicillin G and tetracycline for gonococcal isolates collected in both cities during 1984. In Seattle 37 (18%) and ten (5%) of 205 isolates had MICs for penicillin G of greater than or equal to 1.0 and greater than or equal to 2.0 micrograms/ml, respectively; in Denver eight (3%) of 240 isolates had MICs for penicillin of 1.0 microgram/ml, and none had MICs of greater than 1.0 microgram/ml. For tetracycline.HCl, 107 (52%) and 38 (19%) of Seattle isolates had MICs of greater than or equal to 1.0 and greater than or equal to 2.0 micrograms/ml, respectively, while in Denver the respective figures were 111 (46%) and 48 (20%). In each city, antimicrobial resistance was present in a number of auxotype/serovar (A/S) classes: isolates with MICs for penicillin G of greater than or equal to 1.0 microgram/ml were identified in 15 of 49 A/S classes in Seattle and in five of 49 A/S classes in Denver. These data indicate that chromosomal resistance to penicillin G and tetracycline.HCl varies geographically in prevalence and is a heterogeneous phenomenon involving multiple gonococcal strains.     

Chronisch rezidivierende Infektionen der Haut und Weichgewebe durch Staphylococcus aureus

Staphylococcus aureus is one of the major pathogens causing chronic skin and soft tissue infections. Particularly isolates producing Panton-Valentine leukocidin (PVL) comprising methicillin-susceptible and community-associated methicillin-resistant S. aureus (CA-MRSA) have been associated with more aggressive and persistent or relapsing courses. Beyond classical resistance mechanisms, functional resistance as shown by the small colony-variant (SCV) phenotype could be also responsible for treatment failures, despite the administration of antibiotics tested in vitro as susceptible. Also this phenotype has been associated with chronic courses of infections often with multiple exacerbations. Due to their ability to persist intracellularly, SCVs are protected from host defense and antibiotic treatment if only extracellularly active agents are administered. Reduced growth, abnormal colony morphology and changes in the metabolism of the SCVs aggravate drastically their identification, differentiation and susceptibility testing. The diagnostic and therapeutic challenges of PVL-positive and SCV isolates necessitate close collaboration with microbiological and infectious disease specialists.