Survival of infectious Pseudomonas aeruginosa genotypes in occupational saturation diving environment and the significance of these genotypes for recurrent skin infections

BACKGROUND: Occupational saturation divers suffer from various skin disorders, of which skin infections are the most serious and frequent. Pseudomonas aeruginosa is the microbe most often isolated. METHODS: P. aeruginosa isolates from 292 skin infections in operational saturation divers and about 800 isolates from occupational saturation diving systems have been collected during the period 1986 to 1998. Genotyping of the isolates has been performed by using restriction enzyme fragmentation and pulsed field gel electrophoresis. RESULTS: Four hundred and seventy-two P. aeruginosa isolates have been analyzed, of which 181 originate from skin infections in divers. Ninety-seven significantly different P. aeruginosa genotypes have been defined. Some of these genotypes are solely found from skin infections, some solely from the saturation environment and about 25% were found both from infections and from the saturation environment. Eight frequent infectious genotypes have been identified, and these are shown to be present over several years, both in infections and in the saturation environment. CONCLUSIONS: The study suggests that skin infections in occupational saturation divers are commonly caused by environmental strains.     

Diver's hand: a skin disorder common in occupational saturation diving

Saturation divers regularly inspect North Sea installations, working at depth for periods of 12-16 days. Diver's hand is a particular problem in saturation diving, and there is no effective protection or treatment available. This paper presents the occurrence of diver's hand and describes the disease in clinical and epidemiological terms. Three studies of diver's hand have been carried out, in 1990, 1994, and 1995. Most long term saturation divers have had diver's hand at some time in their professional career. Diver's hand seems able to occur without any previous skin symptoms, and divers without diver's hand can have several other skin symptoms during a saturation period. It is likely that diver's hand is a specific phenomenon associated with saturation diving.

 

     

多药耐药铜绿假单胞菌的菌株亲缘性分析

目的 分析20株多药耐药铜绿假单胞菌(MDRPA)的药敏率及菌株亲缘性关系,为医院感染实时监测提供参考依据.方法 收集柳州市三级医院2011年1-12月标本中分离的MDRPA共20株,采用聚合酶链反应(PCR)的方法分析33种β-内酰胺酶基因、15种氨基糖苷类修饰酶基因、6种16S rRNA甲基化酶基因、15种可移动遗传元件标记基因、oprD2膜孔蛋白基因,并对检测结果作样本聚类分析.结果 20株多药耐药铜绿假单胞菌对庆大霉素、妥布霉素、阿米卡星、环丙沙星、左氧氟沙星的耐药率均为60.00％,敏感率均为40.00％;样本聚类分析示存在7个克隆传播.结论 MDRPA携带获得性耐药基因可导致对相关抗菌药物耐药,且可移动遗传元件的水平转移,使细菌的耐药性在同种细菌之间甚至不同种细菌之间得以快速传播.     

264株铜绿假单胞菌耐药性分析

目的了解临床分离的铜绿假单胞菌(PAE)的耐药情况,指导临床合理用药。方法对医院2008年1月-2009年12月,临床各科室送检的标本中分离的264株铜绿假单胞菌药敏结果进行统计分析。结果 264株铜绿假单胞菌临床科室分布ICU占36.0%、脑外伤占24.8%、呼吸内科占20.7%、泌尿外科占4.2%、内分泌科占3.4%、其他占10.9%;对常用抗菌药物的耐药率阿米卡星为17.4%,亚胺培南为20.8%、美罗培南为18.9%、头孢他啶为34.9%、头孢曲松为62.9%、头孢噻肟为67.8%,对哌拉西林/他唑巴坦、头孢哌酮/舒巴坦、阿米卡星、左氧氟沙星等抗菌药物有较高的敏感率。结论临床分离的PAE对常用抗菌药物不同程度耐药,应加强其耐药性检测,合理应用抗菌药物。     

铜绿假单胞菌168株感染的耐药分析

铜绿假单胞菌广泛分布于外界环境 ,主要寄居于人体皮肤、呼吸道、消化道和生殖道 ,是常见的引起院内感染的条件致病菌。该菌引起的感染可经血行传播 ,引起菌血症 ,使其具有难治性和持续性等特点。为探讨郧阳医学院附属太和医院铜绿假单胞菌感染的分布及耐药情况 ,对该院 2 0 0 2年内采集的各种临床标本中分离得到的 16 8株铜绿假单胞菌进行分析 ,现将结果报告如下。1　材料和方法1.1　菌株来源　从该院 2 0 0 2年各种临床标本中分离并得到 16 8株铜绿假单胞菌。标本来源以痰标本最多 (131例 ) ,其次为创口分泌物 (2 4例 ) ,其他 13例 (咽拭 …     

Pseudomonas aeruginosa as a cause of infectious diarrhoea.

Pseudomonas aeruginosa is not generally considered a cause of infectious diarrhoea. However, it was the predominant organism isolated from the faeces of 23 unrelated, hospital outpatients investigated in the course of a year for persistent (> 1 week duration) diarrhoea. To investigate the possible aetiological role of P. aeruginosa, these patient histories were reviewed and a selection of their faecal isolates were investigated in vitro (n > or = 10) and in vivo (n = 2) for virulence. The patients had a mean age of 60 years, were receiving antibiotics and/or had an underlying illness. Extensive microbiological investigations identified no other potential or recognized enteropathogen in the faeces of 20 of these patients. More than 40% of the isolates tested were able to adhere to HEp-2 cells and exhibited twitching motility (type IV pili), properties indicative of their ability to colonize the human intestine. Cytotoxic activity was demonstrated in bacterium-free cell supernatants of over 80% of isolates; supernatants of four isolates tested in infant mice were weakly enterotoxigenic. Two isolates intragastrically inoculated into clindamycin pre-treated rats established persistent infections and induced signs and symptoms of enteritis. Overall these findings suggest that P. aeruginosa can cause diarrhoea particularly in immunodeficient individuals.     

Complications of saturation diving.

The experience of 458 man-dives with 731 excursions between 50 m and 300 m carried out by Royal Navy saturation divers is summarized. During saturation decompression there were 6 treated bends and 33 reported niggles. Two bends occurred in dives deeper than 249 m and the remaining 4 bends occurred in dives where decompression began in much less than the saturation stop time after completion of downward excursions. There was one case of vestibular system decompression sickness after an excursion to 300 m. It is concluded that the decompression table is effective in use shallower than 150 m but that the risk increases with greater depth. There is, however, only limited experience in the deeper range. There is no evidence that chamber compression with air to 10 m adversely affects decompression from deeper than 50 m. An account of the medical and physiological conditions affecting divers in these dives is given.     

Neuropsychologic effects of saturation diving

Neuropsychologic status of saturation divers was assessed before and after 300-500 msw dives (deep saturation diving--DSD group) and before and after 3.5 yr of ordinary saturation diving (saturation diving--SD group). Average baseline results showed the divers to be slightly superior to nondiving controls. Mild-to-moderate neuropsychologic changes (greater than 10% impairment) were found in measures of tremor, spatial memory, vigilance, and automatic reactivity in 20% of the divers after deep dives (DSD group). One year postdive no recovery was observed except for a vigilance test. In the SD group, 20% of the divers showed greater than 10% impairment after 3.5 yr of ordinary saturation diving. Significant reduction in autonomic reactivity was also found and there was a relationship between low autonomic reactivity before saturation diving and number of greater than 10% impairments. For the whole group (DSD + SD divers), negative correlations were found between saturation experience and results on memory and complex visuomotor tests. Years of diving from first to last examination was positively correlated with number of greater than 10% impairments and with reduction in autonomic reactivity. No similar correlations were found to dive variables after about 3 yr of air diving. The mild-to-moderate changes seen in some divers, therefore, seem to be the effects of saturation diving. Since one deep dive may cause an effect similar to the effect of 3.5 yr of ordinary saturation diving, there is reason to believe that repeated deep diving may lead to more pronounced neuropsychologic impairment.     

Platelet count in deep saturation diving.

Platelet counts were measured in 10 divers during the course of 4 experimental deep dives (450 and 600 m) and different anticoagulants were tested. The use of sodium citrate as an anticoagulant was associated with artifactual thrombocytopenia, whereas ethylenediaminetetraacetic acid proved to be satisfactory. During one of the dives (450 m) the use of fluorocarbon to remove excess dissolved inert gas before decompression of the samples was systematically tested. Mean platelet count decreased from 272,600 +/- 29,400 mm-3 (mean +/- SD) on Day 7 (450 m) to 177,700 +/- 26,400 mm-3 on Day 12 (360 m). Platelet count had recovered to 209,900 +/- 20,700 mm-3 at the time of surfacing. Mean hematocrit (expressed in percent) increased from 44.7 +/- 2.2 predive to 59.4 +/- 2.0 on Day 7 (450 m) to 40.9 +/- 2.8 at the time of surfacing. These changes were statistically significant (P less than 0.05). Platelet counts on samples that had been degassed with fluorocarbon were not different from samples that had been decompressed without degassing.     

258株铜绿假单胞菌耐药性分析

目的分析铜绿假单胞菌对抗菌药物的耐药情况,为临床合理使用抗菌药物提供依据。方法采用常规方法对各临床科室送检的标本进行细菌分离、培养、鉴定及药敏试验。结果铜绿假单胞菌对多种常用抗菌药物的耐药率有逐年增高趋势,耐药率上升较快的抗菌药物有亚胺培南、环丙沙星、左氧氟沙星,分别由2002年的0、8.6%、20.0%增至2004年的9.5%、28.6%、41.0%。结论铜绿假单胞菌对多种抗菌药物耐药,且耐药率逐年增高,在治疗时应根据药敏试验合理谨慎选用抗菌药物,以有效控制及减缓耐药株的产生。     

142株铜绿假单胞菌感染的分布特征及耐药性

目的探讨铜绿假单胞菌感染的分布特征及耐药性。方法回顾性统计分析笔者医院142株铜绿假单胞菌的科室分布、标本类型及耐药性。结果 142株PA的临床分布以ICU病房和神经外科为主,分别占28.2%和25.4%;标本类型以痰液和脓液标本为主,分别占40.1%和30.3%。分离的PA对头孢哌酮/舒巴坦、头孢他啶、头孢吡肟、亚胺培南耐药率较高,在19.7%-24.6%之间。对庆大霉素、左氧氟沙星、环丙沙星的耐药率较低,在10.6%-13.4%之间。对阿米卡星和妥布霉素敏感。结论临床应增加感染病人的标本送检率,根据药敏试验合理使用抗生素,以降低PA的耐药率。     

Evaluation of decompression safety in an occupational diving group using self reported diving exposure and health status

Background: Many occupational diving groups have substantially different diving patterns to those for which decompression schedules are validated.

Aims: To evaluate tuna farm occupational diving practice against existing decompression models and describe a method for collecting and modelling self reported field decompression data.

Methods: Machine readable objective depth/time profiles were obtained from depth/time recorders worn by tuna farm occupational divers. Divers' health status was measured at the end of each working day using a self administered health survey that produces an interval diver health score (DHS) with possible values ranging from 0 to 30. Depth/time profiles were analysed according to existing decompression models. The contribution of diving exposure and between diver variability to DHS was evaluated using linear regression.

Results: The mean risk of decompression sickness was calculated as 0.005 (SD 0.003, n = 383). The mean DHS following diving was 3 (SD 2, n = 383) and following non-diving activities was 1 (SD 1, n = 41). After accounting for between diver variability in intercept, DHS was found to increase one unit for every 1% increase in the risk of decompression sickness.

Conclusions: A method has been established for the collection and analysis of self reported objective decompression data from occupational diving groups that can potentially be used as the basis for development of purpose designed occupational diving decompression schedules.

     

氦氧饱和潜水实验人群铜绿假单胞菌鉴定及毒力研究

目的 调查参与某次氦氧饱和实验的潜水作业人群皮肤粘膜日常携带铜绿假单胞菌及其毒力情况.方法 用生化鉴定法对细菌进行分类;稀释平板法分析分离菌株生长特征;分光光度法测定绿脓菌素含量;动物染毒法观察分离菌毒力.结果 27名潜水员中有6名被检出携带铜绿假单胞菌,检出率为22.22％,其生长曲线与对照组铜绿假单胞菌标准株PAO1的生长曲线差异无统计学意义(P＞0.05);被检出的6株铜绿假单胞菌中有4株绿脓菌素试验为阳性;分离菌株均能造成小鼠致死性感染,绿脓菌素测定为阴性的分离菌株致死率低于绿脓菌素测定为阳性的分离菌株(P＜0.05).结论 在潜水人群中,铜绿假单胞菌广泛存在,在高气压潜水作业过程中极易发生急性感染,应采取必要防控措施.     

62株铜绿假单胞菌的临床分布及耐药性分析

目的 了解医院感染铜绿假单胞菌临床科室分布及耐药趋势,为临床合理选用抗菌药提供依据.方法 铜绿假单胞菌培养与鉴定按照《全国临床检验操作规程》进行,药敏试验采用K-B纸片扩散法.结果 62株铜绿假单胞菌主要分布在呼吸科、神经外科、血液科,分别占37.10％、16.13％、16.13％;耐药率＞50.00％的抗菌药物为头孢曲松、头孢噻肟、环丙沙星、磺胺甲噁唑/甲氧苄啶;头孢哌酮/舒巴坦最敏感,敏感率为96.77％;亚胺培南、阿米卡星、哌拉西林/他唑巴坦、头孢哌酮、头孢他啶,敏感率＞80.00％;哌拉西林、头孢吡肟、左氧氟沙星、氨曲南,敏感率＞70.00％.结论 铜绿假单胞菌已有明显耐药趋势,应加强监测与控制.     

Virulence determinants in Pseudomonas aeruginosa strains from urinary tract infections.

A total of 121 uropathogenic Pseudomonas aeruginosa strains were examined for production of several virulence-related factors. These strains were distributed in five predominant O-serotypes, i.e. O 4, O 12, O 11, O 6 and O 5, which accounted respectively for 23.9, 23.1, 12.3, 8.2 and 5.7% of isolates. Pyochelin and pyoverdin siderophores were produced by most of the isolates, defective variants occurring at very low frequency (2.4% for pyochelin and 7.4% for pyoverdin). Adherence to uroepithelial cells and production of cytotoxins was demonstrated in 52.8 and 67.7% of the strains, respectively, with higher frequencies for epidemiologically related strains belonging to serotypes O 4 and O 12. Titration of total proteases, elastase and phospholipase C revealed a high degree of heterogeneity among isolates. However, examination of individual O-serotypes by exoenzyme production showed that elevated levels of total proteases and elastase were characteristics of serotypes of minor numerical importance, i.e. O 1, O 10, O 11 and O 17, whilst low levels of elastase were produced by strains belonging to the predominant serotypes, namely O 4 and O 12. Moreover, epidemiologically related strains belonging to serotypes O 4 and O 12 appeared more homogeneous than the whole serogroup, when compared with other groups on the basis of exoenzyme levels.     

临床铜绿假单胞菌多重耐药株外排泵机制研究

目的研究临床分离的多重耐药铜绿假单胞菌MexA-MexB-OprM外排泵的外膜蛋白OprM的表达及泵调节基因mexR突变情况。方法筛选铜绿假单胞菌多重耐药株13株和敏感菌株5株进行外膜蛋白SDS-PAGE分析,比较OprM的表达差异。聚合酶链反应(PCR)法扩增mexR基因,鉴定产物,测序。结果多重耐药菌株组OprM蛋白在相对分子量为49 kD处的各电泳条带较敏感菌株和质控菌株铜绿假单胞菌ATCC 27853的灰度明显增强,其光密度值多重耐药菌株组为157.79,敏感菌株组为132.03,两组比较,差异有显著性(t=19.345,P<0.01);多重耐药菌株mexR基因产物测序,除个别碱基插入外,以A-96→G,G-411→A,C-308→G,T-377→A 4个核苷酸点突变为主,后二者还导致了其编码的氨基酸发生改变,分别为Ala-103→Gly,Val-126→Glu。结论OprM表达增强提示MexA-MexB-OprM外排泵耐药机制参与多重耐药形成。多重耐药菌株的mexR基因均存在点突变,提示mexR基因突变引起MexA-MexB-OprM外排泵表达增强。