Pseudoepidemic of Rhodotorula rubra in patients undergoing fiberoptic bronchoscopy

Between March and June 1988, Rhodotorula rubra was isolated from the bronchial washings of 30 of 56 (54%) patients undergoing bronchoscopy at a North Carolina community hospital. Pulmonary disease consistent with invasive fungal pneumonia was not apparent for any patient. Repeat sputum cultures were performed on 11 patients, none of whom were positive for R rubra. Investigation revealed fungal contamination of two brushes used to clean the bronchoscope channels and one positive sample of the tub water used to test the integrity of the bronchoscope prior to cleaning and disinfection. Control measures instituted were high-level disinfection of all equipment used to clean the bronchoscopes, including the brushes, complete air drying of the bronchoscopes before storing and storage of equipment in closed cabinets. An additional case one month after instituting these measures prompted the addition of a final 70% ethyl alcohol rinse of the bronchoscopes immediately prior to storage. Over a six-month period no additional cases have been identified. Despite published disinfection guidelines, pseudoepidemics and infections from contaminated equipment continue to appear. This pseudoepidemic investigation revealed a site for contaminating bronchoscopes that has not been previously reported, the inner cannula cleaning brushes. This emphasizes the need for stringent adherence to recommended cleaning and disinfection guidelines.     

次氯酸消毒剂应用于全自动软式内镜清洗消毒机的消毒效果

目的研究次氯酸消毒剂应用于全自动软式内镜清洗消毒机消毒纤维支气管镜的消毒效果。方法监测某院2018年6—7月(共计48 d)使用的7条纤维支气管镜。采用次氯酸消毒剂对临床使用后的纤维支气管镜进行机洗消毒5 min,分别采用ATP荧光检测法和滤膜法、倾注法对纤维支气管镜外表面及内腔面的消毒效果进行监测和评价。结果 7条纤维支气管镜共送至消毒供应中心清洗消毒159次。分不同日期随机抽样30次,采用ATP荧光法检测表面洁净度,RLU范围10～64,中位数为22,合格率100%。共检测内腔面159次,滤膜法与倾注法检出菌落计数均为0～6 CFU/件,合格率均为100%。稳定性试验7个周期的结果显示,次氯酸消毒剂应用于全自动内镜清洗消毒机,有效氯的初始浓度为210 mg/L,经一周消毒后,处理内镜20～32条不等,有效氯浓度为74～106 mg/L。结论次氯酸消毒剂应用于全自动软式内镜清洗消毒机消毒纤维支气管镜可达到规定的消毒要求,次氯酸消毒剂机洗使用7 d时仍能保持有效浓度。     

Nosocomial transmission of imipenem-resistant Pseudomonas aeruginosa following bronchoscopy associated with improper connection to the Steris System 1 processor.

OBJECTIVE: To assess nosocomial transmission of imipenem-resistant Pseudomonas aeruginosa (IRPA) following bronchoscopy during August through October 1998. DESIGN: Traditional and molecular epidemiological investigation of a case series. SETTING: University-affiliated community hospital. PATIENTS: 18 patients with IRPA bronchial-wash isolates. INTERVENTIONS: We reviewed clinical data, performed environmental cultures and molecular analysis of all IRPA isolates, and observed disinfection of bronchoscopes. RESULTS: Of 18 patients who had IRPA isolated from bronchoscopic or postbronchoscopic specimens, 13 underwent bronchoscopy for possible malignancy or undiagnosed pulmonary infiltrates. Following bronchoscopy, 3 patients continued to have IRPA isolated from sputum and demonstrated clinical evidence of infection requiring specific antimicrobial therapy. The remaining 15 patients had no further IRPA isolated and remained clinically well 3 months following bronchoscopy. Pulsed-field gel electrophoresis revealed that all strains except one were >95% related. STERIS SYSTEM 1 had been implemented in July 1998 as an automatic endoscope reprocessor (AER) for all endoscopes and bronchoscopes. Inspection of bronchoscope sterilization cycles revealed incorrect connectors joining the bronchoscope suction channel to the STERIS SYSTEM 1 processor, obstructing peracetic acid flow through the bronchoscope lumen. No malfunction warning was received, and spore strips remained negative. CONCLUSIONS: The similarity of diverse connectors and limited training by the manufacturer regarding AER for bronchoscopes were the two factors responsible for the outbreak. Appropriate connections were implemented, and there was no further bronchoscope contamination. We suggest active surveillance of all bronchoscopy specimen cultures, standardization of connectors of various scopes and automated processors, and systematic education of staff by manufacturers with periodic on-site observation.     

Comparison of two methods for assessing the removal of total organisms and pathogens from the skin.

A standard hand-wash sampling technique was compared with a simple finger-streak sampling method in assessing the relative effectiveness of a number of alternative preparations used for disinfecting the surgeon''s hands (alcoholic 0.5% chlorhexidine, alcoholic 0.1% tetrabrom-o-methyl phenol, a 4% chlorhexidine detergent solution, aqueous 0.5% chlorhexidine, 2% ''Irgasan'' detergent solution and, as control, bar soap). There was a fairly good correlation between the results of assessment by the two methods after a single disinfection and after six disinfections, three on one day and three on the next. Significant differences were shown in 21 comparisons between treatments when the hand-wash sampling test was used, and 16 of these comparisons also showed a significant difference by the finger-streak test. Staphylococcus aureus was found in hand samplings from 5 out of 8 nurses in the Burns Unit of Birmingham Accident Hospital by the hand-wash sampling method and from 2 of the same 8 nurses by the finger-streak method; the numbers were small, and no Staph. aureus were isolated from the same hands after 1 min. wash in 70% ethyl alcohol. Similar sampling on 29 nurses in other wards showed Staph. aureus on 3 nurses (one in large numbers) by the hand-wash technique and on 1 nurse by the finger-streak test; in only 1 nurse whose hands showed Staph. aureus before disinfection was the organism found, by hand-wash sampling, after disinfection. Parallel sampling of nurses'' hands after washing with soap and water and after disinfection with 95% ethanol showed larger numbers of Staph. aureus in a hospital for skin diseases than in a general hospital, and a lower incidence and somewhat lower density of Staph. aureus after ethanol treatment than after washing with soap and water; Gram-negative bacilli, on the other hand, were commoner on hands in the general than in the skin hospital, and present in much smaller numbers after disinfection with ethanol than after washing with soap and water. Antibiotic sensitivity tests showed the frequent recurrence on the hands of some nurses of multi-resistant Staph. aureus with resistance patterns similar to those found in infective lesions in some of the patients; different sensitivity patterns were usually found in staphylococci isolated from the nose. Even in wards where many patients were infected, carriage by nurses'' hands of a particular strain of Staph. aureus did not seem to last for more than a few days.     

A pseudo-outbreak of Aureobasidium species lower respiratory tract infections caused by reuse of single-use stopcocks during bronchoscopy.

OBJECTIVE: To investigate and control an apparent outbreak of lower respiratory tract infections due to Aureobasidium species. DESIGN: Outbreak investigation. SETTING: University-affiliated medical center. PATIENTS: Nine patients who underwent bronchoscopy between June and August 1998. RESULTS: Ten bronchoalveolar lavage (BAL) fluid cultures from nine patients grew Aureobasidium species during the outbreak period; whereas, respiratory specimens from only two patients grew Aureobasidium species during the preceding 6 years. No patient was judged to have true infection due to Aureobasidium species either before or after bronchoscopy. Nine of the 10 bronchoscopies that yielded Aureobasidium species were performed in the outpatient bronchoscopy suite. The Aureobasidium isolates were not associated with any one bronchoscope. Observation of bronchoscopy procedure revealed that plastic stopcocks labeled for single use were reused on different patients during BAL. There was no record of how many times each stopcock was being reused. After each use, the stopcocks were placed in an automated disinfection machine designed for bronchoscopes. Culture of the stopcocks after they had been "disinfected" yielded a heavy growth of Aureobasidium species, while culture of fluid from the automated disinfection machine was negative. Reuse of the stopcocks was halted, and, during the following 6-month period, Aureobasidium species were not isolated from any BAL specimen. CONCLUSIONS: Reuse of medical equipment labeled for single use is potentially hazardous, especially if no quality control system is in place to monitor sterility and function after reprocessing.     

醋酸氯己定乙醇喷雾剂对医务人员手消毒的现场试验

[目的]观察某皮肤消毒液对医务人员手的消毒效果。[方法]以30名受试者的手为对象进行了现场消毒试验。[结果]以消毒液原液（含醋酸氯己定0．45％～0．50％，乙醇70％～75％）直接对准受试者右手进行均匀喷雾，作用1min后，对手表面自然菌杀灭对数值为1．11～2．47，平均杀灭对数值为1．51。[结论]该复方消毒液对手表面自然菌具有良好的杀灭效果，可用于医务人员的手消毒。     

Pseudo-outbreak of Pseudomonas aeruginosa and Serratia marcescens related to bronchoscopes.

OBJECTIVE: To investigate an apparent outbreak involving simultaneous isolation of Pseudomonas aeruginosa and Serratia marcescens from bronchoalveolar lavage (BAL) samples. DESIGN: Retrospective and prospective cohort studies using chart review, environmental sampling, and ribotyping of all available isolates. Cleaning and disinfection procedures for the bronchoscopes were also evaluated. SETTING: A 380-bed private hospital in S?o Paulo, Brazil PATIENTS: Forty-one patients who underwent bronchoscopic procedures between December 1994 and October 1996 and from whom P. aeruginosa and S. marcescens were concomitantly isolated. Bronchoscopes and related items were microbiologically assessed. RESULTS: P. aeruginosa and S. marcescens were simultaneously isolated from BAL samples 12.6% of the time (41 of 324) during the epidemic period versus 1.8% of the time (1 of 54) in the pre-epidemic period (P = .035). Ribotyping revealed two strains of P. aeruginosa and one of S. marcescens that were isolated from BAL samples of patients with no signs of respiratory tract infection, suggesting a pseudo-outbreak. Evaluation of bronchoscope disinfection revealed that inappropriate methods were being used. Implementation of simple control measures resulted in a significant decrease in simultaneous isolation of these species. CONCLUSION: Prevention of pseudo-outbreaks requires meticulous use of preventive measures for infection-prone medical procedures.     

The effectiveness of ethanol gauze for hand disinfection in surgical wards

The effectiveness of ethanol gauze in removing transient bacteria on the hands was investigated in a surgical ward during clinical nursing rounds. Two nurses with similar duties were selected as subjects for each round; one disinfected her hands with ethanol gauze when moving between patients while the other immersed her hands in 0.05% aqueous chlorhexidine gluconate when aware of contaminating her hands. Hand samples were taken after preliminary disinfection before the round, and again after the round on 37 occasions. Pseudomonas aeruginosa and Staphylococcus aureus were not detected in nurses using ethanol gauze, except in one nurse where S. aureus was isolated from both the pre- and postround hand culture. Both organisms were detected on four occasions from the postround hand cultures in the chlorhexidine group. Acinetobacter anitratus was not removed by pre-round disinfection, and was found on five and 11 occasions from the postround hand cultures in the ethanol gauze and chlorhexidine groups, respectively.     

Inactivation of feline calicivirus, a surrogate of norovirus (formerly Norwalk-like viruses), by different types of alcohol in vitro and in vivo

Hand disinfection is an important measure to prevent transmission of norovirus (formerly called Norwalk-like viruses) from hands or environmental surfaces to other objects. Therefore, three types of alcohol (ethanol, 1- and 2-propanol) were examined for their virus-inactivating properties against feline calicivirus (FCV) as a surrogate for norovirus. Tests were performed as quantitative suspension assays or as in vivo experiments with artificially contaminated fingertips. The in vitro experiments showed that 1-propanol was more effective than ethanol and 2-propanol for the inactivation of FCV: in tests with the 50 and 70% solutions of the different alcohols, a 10(4)-fold reduction was observed with 1-propanol after 30 s, whereas the other alcohols were effective only after 3 min contact time. The greatest efficacy did not occur at the highest concentrations (80%). The following concentrations (extrapolated data) showed the greatest virus-inactivating properties in the suspension test: ethanol 67%, 2-propanol 58% (exposure times of 1 min) and 1-propanol 60% (exposure time of 30 s). The results from fingertips experiments with 70 and 90% solutions and an application time of 30 s confirmed these findings: the 70% alcoholic solutions were more effective than the 90% solutions. In contrast to the suspension tests, 70% ethanol showed the greatest efficacy in vivo with a log(10) reduction factor (RF) of 3.78 compared with 70% 1-propanol (RF 3.58), 70% 2-propanol (RF 2.15) and hard water (RF 1.23). Ethanol and 1-propanol-based solutions with a high alcohol content thus appear most effective.     

Pseudomonas aeruginosa contamination of fibreoptic bronchoscopes

A pseudo-epidemic of Pseudomonas aeruginosa pulmonary infection was traced to a contaminated fibreoptic bronchoscope. A syndrome consistent with Ps. aeruginosa pneumonia developed in one immunosuppressed patient within 72 h of bronchoscopy. The controversy regarding proper cleaning, disinfection and sterilization guidelines for the fibreoptic bronchoscope is reviewed. Routine surveillance of bronchial wash cultures by the hospital infection control team is advocated to facilitate detection of a contaminated bronchoscope.     

麻醉机全麻手术后患者肺部感染临床分析

目的 针对麻醉机细菌污染与手术后患者发生肺部感染的情况进行分析.方法 回顾性分析医院2010年1月-2011年12月在分别使用环氧乙烷与含氯消毒液对麻醉机及其配件进行消毒处理后的效果,分析全麻手术后患者肺部感染的相关因素.结果 采用环氧乙烷对麻醉机及其配件进行消毒处理后,经细菌培养检验,附着在机体及其配件上菌株阳性率为1.67％,含氯消毒液浸泡消毒过的麻醉机及其配件阳性率为13.33％,两者比较,差异有统计学意义(x2 =8.675,P＜0.01).结论 对麻醉机及其配件进行规范消毒处理对降低应用麻醉机全麻术后患者肺部感染有重要价值.     

Double-blind comparative study on the care of the neonatal umbilical cord using 80% ethanol with or without chlorhexidine

We conducted a double-blind comparative study on the effectiveness of 80% ethanol (EtOH), with or without chlorhexidine (CHD), in the prevention of neonatal umbilical colonization by Staphylococcus aureus, the most frequently isolated pathogen on the neonatal umbilicus in the early period. A total of 100 neonates born at the National Tokyo Medical Centre from March to May 2000 and nursed at a maternity ward were enrolled. Forty-eight were randomly allocated to the group for whom umbilical cord disinfection was performed using 80% EtOH containing 0.5% CHD (CHD group) and 52 to disinfection with 80% EtOH alone (EtOH group). The mothers of the neonates and the nursing staff were unaware as to which disinfectant was being used. Disinfection of the umbilicus and the surrounding area was done immediately after birth and twice daily thereafter, after bathing and in the evening, throughout the hospitalization period. Specimens for bacterial culture were taken from the umbilical cord and surrounding skin on day 4 or 5 after birth. As a disinfectant susceptibility test, we checked the minimum killing concentration (MKC) of CHD and EtOH. There was no statistically significant difference between the two groups with respect to sex, gestation period, birthweight, APGAR score or delivery method. In the CHD group, S. aureus was isolated from 25% of the patients, while it was isolated from 57.7% in the EtOH group (P<0.001). In the CHD group, 50% of the S. aureus strains were MRSA, compared with 73.3% in the EtOH group (non-significant). All the S. aureus strains were killed by the combination of both CHD and EtOH at the concentrations used. In terms of the MKC90, there was no significant difference between the CHD group and the EtOH group. For the daily care of the neonatal umbilicus, disinfection using 80% EtOH containing CHD was found to be more effective than that using 80% EtOH alone in preventing colonization by S. aureus.     

A method to evaluate the cleaning and disinfectant action of surface disinfectants

Surface disinfection tests, used to evaluate new disinfectants, do not take into account the effects of detergents or of the mechanical cleaning process. We describe methods which evaluate both the disinfection and cleaning effect of disinfectants on organic matter. When testing alcohols at high concentrations (greater than or equal to 70%) on blood spots contaminated with Staphylococcus aureus, we found that the organisms were trapped and fixed to the test surface, probably due to denaturation of the blood. This gave a low inactivating factor (IF), as well as a poor subjective cleaning effect (SC). If serum was used instead of blood, we observed less pronounced trapping, resulting in a high IF although the SC was still poor. When broth was used, both IF and SC were satisfactory. With alcohols at a concentration of 42%, trapping was markedly reduced which improved the SC in blood contamination, with serum or broth contamination trapping did not occur. However, 42% ethanol lost its killing effect (i.e. low IF), whereas 42% isopropanol still demonstrated a high IF.     

Bacterial contamination of hospital pagers.

We assessed the bacterial contamination of the pagers of healthcare personnel and the efficacy of disinfection with 70% isopropyl alcohol. Microorganisms were isolated from all pagers; 21% yielded Staphylococcus aureus, of which 14% were methicillin resistant. Cleaning with alcohol reduced the total colony count by an average of 94%. Bacterial load varied by healthcare worker group and service assignment.     

2010—2012 年北京市昌平区托幼机构日常预防性消毒效果

目的了解北京市昌平区托幼机构日常预防性消毒效果,及时发现并纠正日常预防性消毒工作中存在的问题,为切实做好托幼机构的传染病防治工作奠定基础。方法对昌平区70所托幼机构2010--2012年日常预防性消毒效果监测资料进行回顾性分析与研究。结果2010--2012年在昌平区70所托幼机构分别采集儿童餐饮用具、玩具及室内空气等各类样品2498件,经检测合格2178件,合格率为87．19％;2010--2012年各年度样品检测合格率依次分别为82．17％、86．59％和97．38％;其中工作人员手、室内空气、各类物体表面和餐饮用具的样品检测合格率依次分别为70．08％、82．37％、87．17％和93．47％;不同季节样品检测合格率变化不明显。结论近3年昌平区托幼机构日常预防性消毒效果呈逐年升高趋势。制定完善的消毒隔离工作制度,设置消毒隔离专职领导和专（兼）职工作人员,配备必须的消毒设备及消毒药物,提高工作人员消毒隔离知识水平,是保证日常预防性消毒效果的重要条件。     

Outbreaks of contaminated broncho-alveolar lavage related to intrinsically defective bronchoscopes

From 5 March 2001 to 19 October 2001, outbreaks of broncho-alveolar lavage (BAL) contamination with Enterobacteraceae were detected in our 700-bed institution. We report the investigation of these outbreaks. A case was defined as the occurrence of pairs of specific Enterobacteraceae in BAL specimens among any patients who underwent bronchoscopy in the respiratory unit during the period of the outbreak. Contamination was identified in 117 BAL samples during three outbreaks among 418 patients, and was associated with bronchoscopes 11 and 12 (P<0.001). The other five devices in use were not linked with the outbreaks. During the first outbreak, particular pairs of micro-organisms were associated with a specific bronchoscope (Klebsiella pneumoniae/Proteus vulgaris with bronchoscope 11, and Morganella morganii/Proteus mirabilis with bronchoscope 12). Cultures of sputa from two patients also yielded M. morganii some days after bronchoscopic examination. Isolates from contaminated BAL samples and bronchoscope 11 had similar patterns by pulsed-field gel electrophoresis. No further cases occurred after removal of the implicated bronchoscopes. No deficiencies in disinfection procedures were detected and the source of contamination was found to be a loose port of the biopsy channel of the bronchoscope. Our findings underscore the urgent need to test bronchoscopic samples regularly and to improve the design and structure of bronchoscopes.     

In vivo roles of alcohol dehydrogenase (ADH), catalase and the microsomal ethanol oxidizing system (MEOS) in deermice

The relative importance of ADH and MEOS for ethanol oxidation in the liver has yet to be elucidated. The discovery of a strain of deermice genetically lacking ADH (ADH-) which can consume ethanol at greater than 50% of the rates seen in deermice having ADH (ADH+) suggested a significant role for non-ADH pathways in vivo. To quantitate contributions of the various pathways, we examined first the ethanol oxidation rates with or without 4-methylpyrazole in isolated deermice hepatocytes. 4-Methylpyrazole significantly reduced the ethanol oxidation in both ADH+ and ADH- hepatocytes. The reduction seen in ADH- cells can be applied to correct for the effect of 4-methylpyrazole on non-ADH pathways of ADH+ deermouse hepatocytes. After correction, non-ADH pathways were found to contribute 28% of ethanol metabolism at 10 mM and 52% at 50 mM. When using a different approach namely measurement of the isotope effect, MEOS was calculated to account for 35% at low and about 70% at high blood ethanol concentrations. Thus, we found that two different complementary approaches yielded similar results, namely that non-ADH pathways play a significant role in ethanol oxidation even in the presence of ADH.     

麻醉相关因素与下呼吸道医院感染的研究

目的探讨气管插管全身麻醉患者院内下呼吸道感染的相关因素和有效的预防措施。方法从麻醉机回路内、病毒/细菌过滤器和气管插管全身麻醉患者口腔和支气管内吸取的分泌物做细菌培养。结果术前采样的15台未消毒的麻醉机中有8台细菌培养呈阳性;每例患者术中口腔、支气管分泌物及术后病毒/细菌过滤器均分离出相同细菌;使用一次性病毒/细菌过滤器的病例,术后从麻醉机内和一次性病毒/细菌过滤器麻醉机采样未捡出细菌;未使用一次性病毒/细菌过滤器的病例,术后麻醉机内可分离出与口腔相同的细菌。结论研究结果提示麻醉机很易受到手术患者的污染,而麻醉机的循环使用可将病原菌传播到下一个手术患者,是导致气管插管全身麻醉患者手术后下呼吸道医院感染的重要因素。     

连台手术室两种空气消毒方法的比较

目的比较三氧消毒机和YKX/G100型医用空气消毒净化机,两种消毒方法对连台手术室空气的消毒效果,探讨连台手术空气消毒方法。方法用自然沉降法于消毒前、后和连台手术开始后的不同时段采样监测,观察两种方法对连台手术室空气中自然菌的杀灭效果。结果两种方法均能使空气中自然菌的杀灭率〉85%;三氧机消毒的A手术间,连台手术开始后空气中的菌落数明显上升;空气净化机消毒的B手术间,连台手术开始后空气中的菌落数逐渐下降。结论空气消毒净化机可以缩短手术间隔时间,是解决连台手术有人条件下持续空气消毒的较好方法。     

多功能超微粒雾化机及热烟雾杀虫消毒剂的应用研究

目的观察多功能超微粒雾化机与3%杀虫与消毒热雾剂联合应用技术现场杀虫、灭鼠效果和对集装箱内空气消毒效果。方法将3%杀虫与消毒热雾剂应用于多功能超微粒雾化机,按15 ml/井口剂量对下水道、化粪池井口喷雾杀灭蟑螂,采用目测法观察杀灭前后蟑螂侵害率;10 ml/鼠洞剂量喷雾量对绿化带中的鼠洞喷雾灭鼠,采用堵洞查盗法观察杀灭前后鼠洞盗开率;按3 ml/m3剂量对封闭的集装箱进行空气消毒60min,采用撞击式采样器对空气中自然菌进行消毒前后采样测定消毒效果。结果 24 h观察下水道、化粪池井口对蟑螂杀灭率为100%;24 h观察对绿化带鼠洞的灭洞率为100%;消毒60 min后,对箱内空气中自然菌的平均消除率大于为90%。结论多功能超微粒雾化机与3%杀虫与消毒热雾剂联合应用技术在密闭的场所具有良好的现场杀虫、灭鼠效果和空气消毒效果,将为多种环境提供一种全新的高效、环保、快速、经济、安全的消毒、杀虫和灭鼠方式。