Pseudo-outbreak of Stenotrophomonas maltophilia Due to Contamination of Bronchoscope / 대한진단검사의학회지

BACKGROUND: We noticed an abrupt increase in the isolation of Stenotrophomonas maltophilia from bronchoalveolar lavage (BAL) specimens collected at Chosun University Hospital. We performed surveillance cultures in order to identify the source of what appeared to be a pseudo-outbreak. METHODS: To investigate a possible nosocomial outbreak of S. maltophilia, we performed culture of 11 environmental specimens obtained from a bronchoscopy room and two bronchoscopes. Pulsedfield gel electrophoresis (PFGE) was used to examine the genetic relatedness among the strains of S. maltophilia recovered from BAL specimens of 3 patients and 1 environmental sample, as well as 9 unrelated strains of S. maltophilia as a control. RESULTS: During a 7 day-period in March 2006, S. maltophilia was isolated from the BAL specimens of 7 of 13 (54%) patients, compared to only 5 of 188 (2.6%) patients during the 6-month period prior to that period. S. maltophilia was isolated from 1 of the 11 environmental samples, which was obtained from a fiberoptic bronchoscope suction channel. All 7 patient isolates and one environmental isolate exhibited similar antibiotic susceptibility patterns. PFGE analysis of the genomic DNA from epidemic strains demonstrated an identical banding pattern, whereas each of epidemiologically unrelated strains showed a unique electrophoretic pattern. CONCLUSIONS: Apparently one of the hospital bronchoscopes became contaminated with S. maltophilia during a bronchoscopic procedure. It is likely that subsequent specimen contamination occurred because the bronchoscope had been inadequately cleaned and disinfected. The pseudo-outbreak was controlled successfully by removing the source of infection.

Microbiologic profile of flexible endoscope disinfection in two Brazilian hospitals

BACKGROUD: Endoscopes are routinely used in hospitals and clinics of the world and they can be potential sources of cross-infection when the decontamination process is unsuitable AIM: The routines of flexible endoscope (bronchoscopes, esophagogastroduodenoscopes and colonoscopes) disinfection procedures used in two Brazilian university hospitals were evaluated during a 3-year period METHODS: Aleatory samples from internal channels of endoscopes were collected after patient examination and after cleaning/disinfection procedures RESULTS: A contamination >3 log10 was achieved in samples recovered from endoscopes after patient examination. These samples yielded gram-negative bacilli (n = 142: 56 percent), gram-positive cocci (n = 43: 17 percent), yeast cells (n = 43: 17 percent), and gram-positive bacilli (n = 26: 10 percent). Approximately, 72 out of 149 samples (48.32 percent) collected after undergoing the cleaning and disinfection procedures disclosed gram-negative bacilli (n = 55: 61 percent), gram-positive cocci (n = 21: 23 percent), gram-positive bacilli (n = 8: 9 percent) and yeast cells (n = 6: 7 percent). Esophagogastroduodenoscopes and colonoscopes were the most frequently contaminated devices. Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Enterobacter spp, Serratia marcescens, Proteus mirabilis, Citrobacter freundii, Staphylococcus aureus, Staphylococcus coagulase negative, Micrococcus luteus, Candida albicans, C. tropicalis, C. glabrata, C. guilliermondii, Bacillus spp and Corynebacterium spp were predominantly identified CONCLUSION: Inappropriate cleaning and low times of disinfection were respectively the major factors associated with the presence of microorganisms in colonoscopes and esophagogastroduodenoscopes. By analyzing the identified germs, hospital disinfection was considered of either intermediate or poor level. After this investigation, both university centers improved their previous protocols for...

RACIONAL: Endoscópios são rotineiramente utilizados em hospitais e clínicas e podem ser fontes potenciais de infecção cruzada quando a descontaminação é inadequada OBJETIVO: As rotinas de descontaminação dos endoscópios flexíveis (broncoscópios, gastrocópios e colonoscópios) realizadas em dois hospitais universitários do Brasil foram avaliadas durante 3 anos MATERIAL E MÉTODOS: Amostras aleatórias foram coletadas dos canais internos dos endoscópios, depois que o aparelho era utilizado nos pacientes e após o processo de desinfecção RESULTADOS: Contaminação superior a 103 foi verificada em amostras coletadas após o exame endoscópico, sendo isolado bacilos gram-negativos (n = 142: 56 por cento), cocos gram-positivos (n = 43: 17 por cento), leveduras (n = 43: 17 por cento) e bacilos gram-positivos (n = 26: 10 por cento). Em 72 das 149 amostras coletadas após procedimentos de limpeza e desinfecção, detectou-se bacilos gram-negativos (n = 55: 61 por cento), cocos gram-positivos (n = 21: 23 por cento), bacilos gram-positivos (n = 8: 9 por cento) e leveduras (n = 6: 7 por cento). Gastroscópios e colonoscópios eram os aparelhos com maior freqüência e taxa de contaminação. Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Enterobacter spp, Serratia marcescens, Proteus mirabilis, Citrobacter freundii, Staphylococcus aureus, Staphylococcus coagulase negative, Micrococcus luteus, Candida albicans, C. tropicalis, C. glabrata, C. guilliermondii, Bacillus spp and Corynebacterium spp foram os mais identificados CONCLUSÃO: A limpeza inapropriada e curto período de tempo de desinfecção eram, respectivamente, os maiores fatores associados com a presença de microrganismos em gastroscópios e colonoscópios. De acordo com os organismos isolados, considera-se que a desinfecção nos hospitais era de nível baixo a intermediário. Após a investigação, os centros de endoscopia adequaram seus protocolos, sanando os problemas verificados nos procedimentos...

Efficiency of the glutaraldehyde test strip for monitoring the concentration of glutaraldehyde in reused solutions for disinfecting endoscopes.

BACKGROUND: Glutaraldehyde has been widely used for low-temperature disinfection of endoscopes. The current practice at Siriraj Hospital is to change the glutaraldehyde solution every 21 days or when the solution appears turbid. The disadvantages of this practice include inadequate disinfection of endoscopes if the concentration of glutaraldehyde in a reused solution is insufficient or wasted if the discarded solution is still active. OBJECTIVE: To determine the efficiency of a glutaraldehyde test strip (GTS) in monitoring the amount of glutaraldehyde in a reused solution for disinfecting endoscopes. METHOD: Reused glutaraldehyde solutions for disinfecting bronchoscopes, gastroscopes and colonoscopes were tested for the concentration of glutaraldehyde with a GTS thrice weekly for the first week and then every working day up to 56 days. If the GTS indicated a concentration of glutaraldehyde > or = 1.8 per cent after 21 days, 5 ml of the solution was taken to the laboratory to determine its mycobactericidal activity. RESULTS: All samples of the reused glutaraldehyde solution up to 56 days with a concentration of > or = 1.8 per cent glutaraldehyde on GTS from testings showed mycobactericidal activity. If the glutaraldehyde solution was reused for up to 28, 42 or 56 days, it could save 9,603; 22,813 and 29,415 baht per year respectively for the gastroscopy and colonoscopy units. The corresponding figures were -949; 2,726 and 4,564 baht per year for the bronchoscopy unit. It is estimated that up to 400,000 baht per year could be saved by adopting the strategy of GTS monitoring in all endoscopy units at Siriraj Hospital. CONCLUSION: The current strategy of discarding reused glutaraldehyde solution in the gastroscopy, colonoscopy and bronchoscopy units at Siriraj Hospital may be inappropriate since the reused solution is still mycobactericidal for up to 56 days.

Avaliação do risco de contaminação por bactérias, no paciente submetido à broncoscopia, após o reprocessamento do broncoscópio / Evaluation of the risk of bacterial contamination in the patient submitted to bronchoscopy, after reprocessing the bronchoscope

Introdução: A broncoscopia é um procedimento diagnóstico e terapêutico realizado com a introdução nas vias aéreas de um tubo flexível que permite visualizar até as menores delas. Para evitar ou reduzir o risco de infecções, o broncoscópio deve ser adequadamente desinfetado com, pelo menos, desinfecção de alto nível. Objetivo: Verificar se há risco de contaminação bacteriana para os pacientes submetidos à broncoscopia do Hospital São Paulo da Unifesp, Estado de São Paulo. Métodos: No período de 1997 a 1998, o reprocessamento do broncoscópio incluiu limpeza e enxágüe com água estéril ou potável, seguida de rinsagem com glutaraldeído a 2 por cento por 20 minutos, novo enxágüe com água estéril ou potável e rinsagem com álcool etílico a 70 por cento e secagem com ar forçado pelo canal de sucção. Foram colhidas amostras de 65 pacientes para exames microbiológicos, instalando-se soro fisiológico estéril pelo canal de sucção do broncoscópio. Resultados: Após o reprocessamento foram encontrados nas amostras Staphylococcus epidermidis, Enterobacter sp, Acinetobacter baumanni, Streptococcus viridans, Staphylococcus aureus, Streptococcus beta hemoliticus A, Staphylococcus coagulase negativa e em cinco amostras houve crescimento de microbactéria na cultura. Conclusões: A desinfecç ão do broncoscópio com glutaraldeído a 2 por cento não foi suficiente para garantir a desinfecção do aparelho e a presença de Staphylococcus epidermidis indica que houve contaminação do broncoscópio pela manipulação após a desinfecção