- Email: [email protected]
Ineffectiveness of hospital disinfectants against bacteria: A collaborative study
Arnercan
90
Abstracts
INFECTION
.ioumai CONTROL
MANAGEMENT OF CITROBACTER DIVERSUS COLONIZATION OF PATIENTS IN A NEONATAL INTENSIVE CARE UNIT. K. Schanbscher*, J. Kaplan, H. Chawla. Hahnemann University Hospital, Philadelphia, PA.
INEFFECTIVENESS AGAINST BACTERIA: Cole, W. A. Rutala*. Hill, NC.
Citrobacter diversus has been reported to be a cause of meningitis in the neonate. This disease has a high rate of mortality and serious sequelas for the survivors. The population of a neona tal intensive care unit (ICN) was found to have a C. diversus colonization prevalence of 43%. Six of 14 patients were initially found to have rectal and/or umbilical colonization. Weekly stool cultures, handwashing, and cohorting of patients and staff were used to control the spread of the organism. Two additional patients became colonized during the outbreak. Rectal cultures of ICN personnel as well as environmental cultures remained negative for the organism throughout our investigation. All eight C. &versus isolates had identical antibiograms, but after subsequent investigation, three dilferent strains were identified using plssmid profiles. After ten weeks, we were able to discharge all colonized patients from the ICN and prevent additional cases of colonisti tion. Even though there were no esses of disease among our patients, others have reported a meningitis to colonization ratio of 4%. Based on our experience, we can draw two possible conclusions: 1) our control measures reduced the incidence of colonization and possible meningitis and therefore such relatively stringent control measures would be warranted in similar situations; or 2) since there were three distinctly dilferent strains of G. diversus responsible for the colonization of our patients, the fortuitous discovery of C. diuersus colonization of our ICN patients wss of no clinical significance, and that such colonization of ICN patients may be a common occurrence. Additional research is warranted to identify virulence markers for such strains of C. diversus.
A collaborative study was undertaken to assess the degree of variability in disinfectant efficacy test results smong laboratories that routinely perform the AOAC Use-Dilution Method. Eighteen laboratories tested identical samples of 6 EPA registered, hospital-grade disinfectants (3 phenol& and 3 quaternaries) at the manufacturers’ recommended use-dilution using only those modifications of the method approved by the AOAC Use-Dilution Task Force. Each laboratory processed 60 penicyhnders for each of the 6 randomly-selected disinfectants and 3 test organisms The failure rates (1 positive penicyIinder/66 replicates) of the 6 disinfectants when tested against the AOAC test bacteria (S. choleraesuis ATCC 10708, S. auteus ATCC 6538, P. aeruginosa ATCC 15442) were 20.4% (22/108=6 disinfectants x 18 labs), 34.3% (47/108), and 62.0% (67/108), respectively. Four laboratories unknowingly tested their own products, and 3 of the 4 failed their product against one or more of the test organisms. These results show the inability to reproduce the manufacturers’ bact~eritidal label claims for 6 disinfectants against the 3 AOAC test bacteria. In addition, extreme variability of test results among laboratories testing identical products questions the use of the AOAC Use-Dilution Method for enforcement action
NOSOGOMIAL KLEBSIELLA SEPSIS FOLLOWING HEMODIALYSIS. M. P&cone*, H.C. Neu, N.X. Chin, M. Fracaro, J. Bissinger, H. Bopp. Columbia-Presbyterian Medical Center, New York City, NY.
NOSOCOMIAL LEGIONELLOSIS ASSQCIATED WITH A LOCALIZED OBSTRUCTIGN IN A HOSPITAL WATER SUPPLY. J.E. Patterson*, R. Calderon, D. Dumigan, R.J. Ma@, W.J. Hierholzer,Jr. Yale University School of Medicine and HOSP& tal of St. Raphael, New Haven, CT.
In November 1986, a chart review of patients with bacteremias revealed that there were three cases of Klebeielle pneumonioe sepsis among patients in the dialysis unit. Blotyping and antibiogram comparison revealed that these cases were in fact caused by the same strain of organism. An investigation was conducted to Ilnd the source of the problem and to search for additional cases among the dialyxed patient population. All personnel (total of 28) involved with the dialysis unit had their hands cultured. Environmental culturing inchrded sinks, faucets, dialysate, soap dispensers and hand lotion. Hand culturing revealed that four RNs had positive hand cultures for the Kfebeiefio. The epidemic strain was recovered from the hand lotion. A retrospective review of the 60 cases of KIebsieIle sepsis for 1986 revealed that 2 additional dialysis patients had acquired a bacteremia in the dialysis unit. Control measures instituted to contain the outbreak included a restriction on the use of communal hand lotions for staff members. Removal of the hand lotion from the unit successfully eradicated subsequent episodes of KlebsieUa sepsis. Repeat hand culturing of personnel revealed that one RN remained positive after 3 sets of cultures and was excluded from the unit until cultures became negative.
OF HOSPITAL DISINFECTANTS A COLLABORATIVE STUDY. E C. The University of North Carolina, Chapel
Three cases of nosocomiol Legionello pneumonia at a corn“unity hospital prompted an epidemiologic investigation. Retroepective chart review of confirmed cases of Legiommlre’s Dikeease over the previous year revealed an ongoing esdemiarate of noSacomial legionellosis. Cultures of environmental sources were done and the recent cases were highly associated with contaminated pipes containing the tempered (110 F) water supply in one wingof the hospital. The mean temperatures from water samples on this wing were significantly less than temperatures on the two other wings of the hospital (101.3 F vs. 108.1 F and 107.5 F respectively; p<.O5). Mean free chlorine levels were lower, and mean Legionella colony counts and pH levels were higher on the suspect wing as compared to the other two wings. These findings, snggesting stagnation, prompted further investigation of the water supply. A closed recirculating valve obstructing the implicated water supply was found. This explained the difference in temperature, pH, and colony counts on the implicated wing and Iike$ exphins the locabrsd association of the potable water supply with these casea. Supsrchloriuation was impbamented- to decontaminate the water supply aad the recirculating valve was opened. Temperature and pH in the suspect wing equnlizsd es compnred to the other two wings and repeat culturea were negative. This outbreak illustrates the importance of a snrvey of the plumbing system, incbrding water circulation patterns and valves, in investigations of nosocomial legiunsllosis.
oi
90
Abstracts
INFECTION
.ioumai CONTROL
MANAGEMENT OF CITROBACTER DIVERSUS COLONIZATION OF PATIENTS IN A NEONATAL INTENSIVE CARE UNIT. K. Schanbscher*, J. Kaplan, H. Chawla. Hahnemann University Hospital, Philadelphia, PA.
INEFFECTIVENESS AGAINST BACTERIA: Cole, W. A. Rutala*. Hill, NC.
Citrobacter diversus has been reported to be a cause of meningitis in the neonate. This disease has a high rate of mortality and serious sequelas for the survivors. The population of a neona tal intensive care unit (ICN) was found to have a C. diversus colonization prevalence of 43%. Six of 14 patients were initially found to have rectal and/or umbilical colonization. Weekly stool cultures, handwashing, and cohorting of patients and staff were used to control the spread of the organism. Two additional patients became colonized during the outbreak. Rectal cultures of ICN personnel as well as environmental cultures remained negative for the organism throughout our investigation. All eight C. &versus isolates had identical antibiograms, but after subsequent investigation, three dilferent strains were identified using plssmid profiles. After ten weeks, we were able to discharge all colonized patients from the ICN and prevent additional cases of colonisti tion. Even though there were no esses of disease among our patients, others have reported a meningitis to colonization ratio of 4%. Based on our experience, we can draw two possible conclusions: 1) our control measures reduced the incidence of colonization and possible meningitis and therefore such relatively stringent control measures would be warranted in similar situations; or 2) since there were three distinctly dilferent strains of G. diversus responsible for the colonization of our patients, the fortuitous discovery of C. diuersus colonization of our ICN patients wss of no clinical significance, and that such colonization of ICN patients may be a common occurrence. Additional research is warranted to identify virulence markers for such strains of C. diversus.
A collaborative study was undertaken to assess the degree of variability in disinfectant efficacy test results smong laboratories that routinely perform the AOAC Use-Dilution Method. Eighteen laboratories tested identical samples of 6 EPA registered, hospital-grade disinfectants (3 phenol& and 3 quaternaries) at the manufacturers’ recommended use-dilution using only those modifications of the method approved by the AOAC Use-Dilution Task Force. Each laboratory processed 60 penicyhnders for each of the 6 randomly-selected disinfectants and 3 test organisms The failure rates (1 positive penicyIinder/66 replicates) of the 6 disinfectants when tested against the AOAC test bacteria (S. choleraesuis ATCC 10708, S. auteus ATCC 6538, P. aeruginosa ATCC 15442) were 20.4% (22/108=6 disinfectants x 18 labs), 34.3% (47/108), and 62.0% (67/108), respectively. Four laboratories unknowingly tested their own products, and 3 of the 4 failed their product against one or more of the test organisms. These results show the inability to reproduce the manufacturers’ bact~eritidal label claims for 6 disinfectants against the 3 AOAC test bacteria. In addition, extreme variability of test results among laboratories testing identical products questions the use of the AOAC Use-Dilution Method for enforcement action
NOSOGOMIAL KLEBSIELLA SEPSIS FOLLOWING HEMODIALYSIS. M. P&cone*, H.C. Neu, N.X. Chin, M. Fracaro, J. Bissinger, H. Bopp. Columbia-Presbyterian Medical Center, New York City, NY.
NOSOCOMIAL LEGIONELLOSIS ASSQCIATED WITH A LOCALIZED OBSTRUCTIGN IN A HOSPITAL WATER SUPPLY. J.E. Patterson*, R. Calderon, D. Dumigan, R.J. Ma@, W.J. Hierholzer,Jr. Yale University School of Medicine and HOSP& tal of St. Raphael, New Haven, CT.
In November 1986, a chart review of patients with bacteremias revealed that there were three cases of Klebeielle pneumonioe sepsis among patients in the dialysis unit. Blotyping and antibiogram comparison revealed that these cases were in fact caused by the same strain of organism. An investigation was conducted to Ilnd the source of the problem and to search for additional cases among the dialyxed patient population. All personnel (total of 28) involved with the dialysis unit had their hands cultured. Environmental culturing inchrded sinks, faucets, dialysate, soap dispensers and hand lotion. Hand culturing revealed that four RNs had positive hand cultures for the Kfebeiefio. The epidemic strain was recovered from the hand lotion. A retrospective review of the 60 cases of KIebsieIle sepsis for 1986 revealed that 2 additional dialysis patients had acquired a bacteremia in the dialysis unit. Control measures instituted to contain the outbreak included a restriction on the use of communal hand lotions for staff members. Removal of the hand lotion from the unit successfully eradicated subsequent episodes of KlebsieUa sepsis. Repeat hand culturing of personnel revealed that one RN remained positive after 3 sets of cultures and was excluded from the unit until cultures became negative.
OF HOSPITAL DISINFECTANTS A COLLABORATIVE STUDY. E C. The University of North Carolina, Chapel
Three cases of nosocomiol Legionello pneumonia at a corn“unity hospital prompted an epidemiologic investigation. Retroepective chart review of confirmed cases of Legiommlre’s Dikeease over the previous year revealed an ongoing esdemiarate of noSacomial legionellosis. Cultures of environmental sources were done and the recent cases were highly associated with contaminated pipes containing the tempered (110 F) water supply in one wingof the hospital. The mean temperatures from water samples on this wing were significantly less than temperatures on the two other wings of the hospital (101.3 F vs. 108.1 F and 107.5 F respectively; p<.O5). Mean free chlorine levels were lower, and mean Legionella colony counts and pH levels were higher on the suspect wing as compared to the other two wings. These findings, snggesting stagnation, prompted further investigation of the water supply. A closed recirculating valve obstructing the implicated water supply was found. This explained the difference in temperature, pH, and colony counts on the implicated wing and Iike$ exphins the locabrsd association of the potable water supply with these casea. Supsrchloriuation was impbamented- to decontaminate the water supply aad the recirculating valve was opened. Temperature and pH in the suspect wing equnlizsd es compnred to the other two wings and repeat culturea were negative. This outbreak illustrates the importance of a snrvey of the plumbing system, incbrding water circulation patterns and valves, in investigations of nosocomial legiunsllosis.
oi