Background The environmental sources associated with community-acquired or nosocomial legionellosis were not always detectable in the mainland of China and Hong Kong, China. The objective of this study was to illustra...Background The environmental sources associated with community-acquired or nosocomial legionellosis were not always detectable in the mainland of China and Hong Kong, China. The objective of this study was to illustrate the control measures implemented for nosocomial and community outbreaks of legionellosis, and to understand the environmental distribution of legionella in the water system in Hong Kong, China. Methods We investigated the environmental sources of two cases of legionellosis acquired in the hospital and the community by extensive outbreak investigation and sampling of the potable water system using culture and genetic testing at the respective premises. Results The diagnosis of nosocomial legionellosis was suspected in a patient presenting with nosocomial pneumonia not responsive to multiple beta-lactam antibiotics with subsequent confirmation by Legionella pneumophila serogroup 1 antigenuria. High counts of Legionella pneumophila were detected in the potable water supply of the 70-year-old hospital building. Another patient on continuous ambulatory peritoneal dialysis presenting with acute community-acquired pneumonia and severe diarrhoea was positive for Legionella pneumophila serogroup 1 by polymerase chain reaction （PCR） testing on both sputum and nasopharyngeal aspirate despite negative antigenuria. Paradoxically the source of the second case was traced to the water system of a newly commissioned office building complex. No further cases were detected after shock hyperchlorination with or without superheating of the water systems. Subsequent legionella counts were drastically reduced. Point-of-care infection control by off-boiled or sterile water for mouth care and installation of water filter for showers in the hospital wards for immunocompromised patients was instituted. Territory wide investigation of the community potable water supply showed that 22.1% of the household water supply was positive at a mean legionella count of 108.56 CFU/ml （range 0.10 to 639.30 CFU/ml）. Conclusions Potable water systems are open systems which are inevitably colonized by bacterial biofilms containing Legionella species. High bacterial counts related to human cases may occur with stagnation of flow in both old or newly commissioned buildings. Vigilance against legionellosis is important in healthcare settings with dense population of highly susceptible hosts.展开更多
Monochloramine is a well-known disinfectant for drinking water with several advantages over chlorine and chlorine dioxide. With these two biocides, monochloramine is included in the US-EPA list of disinfectants for dr...Monochloramine is a well-known disinfectant for drinking water with several advantages over chlorine and chlorine dioxide. With these two biocides, monochloramine is included in the US-EPA list of disinfectants for drinking water. At the beginning of XXI century, epidemiological studies demonstrated its superior ability to control Legionella in hot water health-care premises. In 2005 a research program started to set up a reliable and effective method to produce monochloramine directly in domestic hot water systems, at the safest concentration and without accumulation of by-products. Results of these researches, which has been carried out with the collaboration of Italian and American Institutions showed that monochloramine can be safely and reliably prepared and that it is the best approach to Legionella remediation in health-care facilities.展开更多
BACKGROUND Legionella pneumophila(L.pneumophila)is a gram-negative intracellular bacillus composed of sixteen different serogroups.It is mostly known to cause pneumonia in individuals with known risk factors as immuno...BACKGROUND Legionella pneumophila(L.pneumophila)is a gram-negative intracellular bacillus composed of sixteen different serogroups.It is mostly known to cause pneumonia in individuals with known risk factors as immunocompromised status,tobacco use,chronic organ failure or age older than 50 years.Although parapneumonic pleural effusion is frequent in legionellosis,pleural empyema is very uncommon.In this study,we report a case of fatal pleural empyema caused by L.pneumophila serogroup 1 in an 81-year-old man with multiple risk factors.CASE SUMMARY An 81-year-old man presented to the emergency with a 3 wk dyspnea,fever and left chest pain.His previous medical conditions were chronic lymphocytic leukemia,diabetes mellitus,chronic kidney failure,hypertension and hyperlipidemia,without tobacco use.Chest X-ray and comouted tomographyscan confirmed a large left pleural effusion,which puncture showed a citrine exudate with negative standard bacterial cultures.Despite intravenous cefotaxime antibiotherapy,patient’s worsening condition after 10 d led to thoracocentesis and evacuation of 2 liters of pus.The patient progressively developed severe hypoxemia and multiorgan failure occurred.The patient was treated by antibiotherapy with cefepime and amikacin and with adequate symptomatic shock treatment,but died of uncontrolled sepsis.The next day,cultures of the surgical pleural liquid samples yielded L.pneumophila serogroup 1,consistent with the diagnosis of pleural legionellosis.CONCLUSION L.pneumophila should be considered in patients with multiple risk factors and undiagnosed pleural empyema unresponsive to conventional antibiotherapy.展开更多
Legionella pneumophila infection can cause Legionnaires’disease,a severe form of pneumonia.Extrapulmonary manifestations of Legionella infections include myocarditis,pericarditis,and endocarditis.We present a rare ca...Legionella pneumophila infection can cause Legionnaires’disease,a severe form of pneumonia.Extrapulmonary manifestations of Legionella infections include myocarditis,pericarditis,and endocarditis.We present a rare case of pneumonia caused by Legionella pneumophila with a possible etiologic link to a recently recovered culture-negative infective endocarditis.展开更多
文摘Background The environmental sources associated with community-acquired or nosocomial legionellosis were not always detectable in the mainland of China and Hong Kong, China. The objective of this study was to illustrate the control measures implemented for nosocomial and community outbreaks of legionellosis, and to understand the environmental distribution of legionella in the water system in Hong Kong, China. Methods We investigated the environmental sources of two cases of legionellosis acquired in the hospital and the community by extensive outbreak investigation and sampling of the potable water system using culture and genetic testing at the respective premises. Results The diagnosis of nosocomial legionellosis was suspected in a patient presenting with nosocomial pneumonia not responsive to multiple beta-lactam antibiotics with subsequent confirmation by Legionella pneumophila serogroup 1 antigenuria. High counts of Legionella pneumophila were detected in the potable water supply of the 70-year-old hospital building. Another patient on continuous ambulatory peritoneal dialysis presenting with acute community-acquired pneumonia and severe diarrhoea was positive for Legionella pneumophila serogroup 1 by polymerase chain reaction （PCR） testing on both sputum and nasopharyngeal aspirate despite negative antigenuria. Paradoxically the source of the second case was traced to the water system of a newly commissioned office building complex. No further cases were detected after shock hyperchlorination with or without superheating of the water systems. Subsequent legionella counts were drastically reduced. Point-of-care infection control by off-boiled or sterile water for mouth care and installation of water filter for showers in the hospital wards for immunocompromised patients was instituted. Territory wide investigation of the community potable water supply showed that 22.1% of the household water supply was positive at a mean legionella count of 108.56 CFU/ml （range 0.10 to 639.30 CFU/ml）. Conclusions Potable water systems are open systems which are inevitably colonized by bacterial biofilms containing Legionella species. High bacterial counts related to human cases may occur with stagnation of flow in both old or newly commissioned buildings. Vigilance against legionellosis is important in healthcare settings with dense population of highly susceptible hosts.
文摘Monochloramine is a well-known disinfectant for drinking water with several advantages over chlorine and chlorine dioxide. With these two biocides, monochloramine is included in the US-EPA list of disinfectants for drinking water. At the beginning of XXI century, epidemiological studies demonstrated its superior ability to control Legionella in hot water health-care premises. In 2005 a research program started to set up a reliable and effective method to produce monochloramine directly in domestic hot water systems, at the safest concentration and without accumulation of by-products. Results of these researches, which has been carried out with the collaboration of Italian and American Institutions showed that monochloramine can be safely and reliably prepared and that it is the best approach to Legionella remediation in health-care facilities.
文摘BACKGROUND Legionella pneumophila(L.pneumophila)is a gram-negative intracellular bacillus composed of sixteen different serogroups.It is mostly known to cause pneumonia in individuals with known risk factors as immunocompromised status,tobacco use,chronic organ failure or age older than 50 years.Although parapneumonic pleural effusion is frequent in legionellosis,pleural empyema is very uncommon.In this study,we report a case of fatal pleural empyema caused by L.pneumophila serogroup 1 in an 81-year-old man with multiple risk factors.CASE SUMMARY An 81-year-old man presented to the emergency with a 3 wk dyspnea,fever and left chest pain.His previous medical conditions were chronic lymphocytic leukemia,diabetes mellitus,chronic kidney failure,hypertension and hyperlipidemia,without tobacco use.Chest X-ray and comouted tomographyscan confirmed a large left pleural effusion,which puncture showed a citrine exudate with negative standard bacterial cultures.Despite intravenous cefotaxime antibiotherapy,patient’s worsening condition after 10 d led to thoracocentesis and evacuation of 2 liters of pus.The patient progressively developed severe hypoxemia and multiorgan failure occurred.The patient was treated by antibiotherapy with cefepime and amikacin and with adequate symptomatic shock treatment,but died of uncontrolled sepsis.The next day,cultures of the surgical pleural liquid samples yielded L.pneumophila serogroup 1,consistent with the diagnosis of pleural legionellosis.CONCLUSION L.pneumophila should be considered in patients with multiple risk factors and undiagnosed pleural empyema unresponsive to conventional antibiotherapy.
文摘Legionella pneumophila infection can cause Legionnaires’disease,a severe form of pneumonia.Extrapulmonary manifestations of Legionella infections include myocarditis,pericarditis,and endocarditis.We present a rare case of pneumonia caused by Legionella pneumophila with a possible etiologic link to a recently recovered culture-negative infective endocarditis.
