Abstract
Aim:
We describe a one-year investigation of colonization by imipenem-resistant, metallo-β-lactamase (MBL) producing Pseudomonas aeruginosa in a neonatal intensive care unit (NICU) of the University Hospital of Palermo, Italy.
Methods:
A prospective epidemiological investigation was conducted in the period 2003 January to 2004 January. Rectal swabs were collected twice a week from all neonates throughout their NICU stay. MBL production by imipenem-resistant strains of P aeruginosa was detected by phenotypic and molecular methods. Pulsed field gel electrophoresis (PFGE) was carried out on all isolates of P aeruginosa. The association between risk factors and colonization by imipenem-resistant, imipenem-susceptible P aeruginosa isolates and other multidrug-resistant Gram negative (MDRGN) organisms was analyzed for variables present at admission and during the NICU stay. Data analysis was carried out by the Cox proportional hazards regression model.
Results:
Twenty-two of 210 neonates were colonized with imipenem-resistant, MBL-producing P aeruginosa isolates and 14 by imipenem-susceptible P aeruginosa isolates. A single pulsotype, named A, was shared by all imipenem-resistant isolates. Colonization by P aeruginosa of pulsotype A was positively correlated with breast milk feeding and administration of ampicillin-sulbactam, and inversely correlated with exclusive feeding by formula. In the Cox proportional hazards regression model, birthweight of more than 2500 g and breast milk feeding were independently associated with an increased risk of colonization by MBL-producing P aeruginosa.
Conclusion:
The results strongly support an association between colonization by a well-defined imipenem-resistant, MBL producing P aeruginosa strain and breast milk feeding. Such a study may highlight the need for implementation of strategies to prevent expressed breast milk from becoming a vehicle of health care-associated infections.
Similar content being viewed by others
Log in or create a free account to read this content
Gain free access to this article, as well as selected content from this journal and more on nature.com
or
References
Grundmann H, Kropec A, Hartung D, Berner R, Daschner F . Pseudomonas aeruginosa in a neonatal intensive care unit: reservoirs and ecology of the nosocomial pathogen. J Infect Dis 1993; 168: 943–7.
Senda K, Arakawa Y, Nakashima K, Ito H, Ichiyama S, Shimokata K, et al. Multifocal outbreaks of metallo-beta-lactamase-producing Pseudomonas aeruginosa resistant to broad-spectrum beta-lactams, including carbapenems. Antimicrob Agents Chemother 1996; 40: 349–53.
zafar AB, Sylvester LK, Beidas So Pseudomonas aeruginosa infections in a neonatal intensive care unit. Am J Infect Control 2002; 30: 425–9.
Blanc DS, Nahimana I, Petignat C, Wenger A, Bille J, Francioli P . Faucets as a reservoir of endemic Pseudomonas aeruginosa colonization/infections in intensive care units. Intensive Care Med 2004; 30: 1964–8.
Trautmann M, Michalsky T, Wiedeck H, Radosavljevic V, Ruhnke M . Tap water colonization with Pseudomonas aeruginosa in a surgical intensive care unit (ICU) and relation to Pseudomonas infections of ICU patients. Infect Control Hosp Epidemiol 2001; 22: 49–52.
Lagatolla C, Edalucci E, Dolzani L, Riccio ML, De Luca F, Medessi E, et al. Molecular evolution of metallo-beta-lactamase-producing Pseudomonas aeruginosa in a nosocomial setting of high-level endemicity. J Clin Microbiol 2006; 44: 2348–53.
Walsh TR . The emergence and implications of metallo-beta-lactamases in Gram-negative bacteria. Clin Microbiol Infect 2005; 11 Suppl 6: 2–9.
Cornaglia G, Mazzariol A, Lauretti L, Rossolini GM, Fontana R . Hospital outbreak of carbapenem-resistant Pseudomonas aeruginosa producing VIM-1, a novel transferable metallo-beta-lactamase. Clin Infect Dis 2000; 31: 1119–25.
Corvec S, Poirel L, Decousser JW, Allouch PY, Drugeon H, Nordmann P . Emergence of carbapenem-hydrolysing metallo-beta-lactamase VIM-1 in Pseudomonas aeruginosa isolates in France. Clin Microbiol Infect 2006; 12: 941–2.
Foca M, Jakob K, Whittier S, Della Latta P, Factor S, Rubenstein D, et al. Endemic Pseudomonas aeruginosa infection in a neonatal intensive care unit. New Engl J Med 2000; 343: 695–700.
Widmer AF, Wenzel RP, Trilla A, Bale MJ, Jones RN, Doebbeling BN . outbreak of Pseudomonas aeruginosa infections in a surgical intensive care unit: probable transmission via hands of a health care worker. Clin Infect Dis 1993; 16: 372–6.
Mammina C, Di Carlo P, Cipolla D, Giuffrè M, Casuccio A, Di Gaetano V, et al. Surveillance of multidrug-resistant Gram-negative bacilli in a neonatal intensive care unit: prominent role of cross-transmission. Am J Infect Control 2007; 35: 222–30.
Gras-Le Guen C, Lepelletier D, Debillon T, Gournay V, Espaze E, Roze JC . Contamination of a milk bank pasteuriser causing a Pseudomonas aeruginosa outbreak in a neonatal intensive care unit. Arch Dis Child Fetal Neonatal Ed 2003; 88: 434–5.
Thom AR, Cole AP, Watrasiewicz K . Pseudomonas aeruginosa infection in a neonatal nursery, possibly transmitted by a breast-milk pump. Lancet 1970; 7646: 560–1.
Garner JS, Jarvis WR, Emori TG, Horan TC, Hughes JM . CDC definitions for nosocomial infections Am J Infect Control 1988; 16: 128–40.
Clinical and Laboratory Standards Institute. Performance standards for antimicrobial susceptibility testing. 15th International supplement. CLSI documente M100-S15. Wayne: CLSI; 2005.
Lee K, Chong Y, Shin HB, Kim YA, Yong D, Yum JH . Modified Hodge and EDTA-disk synergy tests to screen metallo-β-lactamase-producing strains of Pseudomonas and Acinetobacter strains. Clin Microbiol Infect 2001; 7: 88–91.
Sader HS, Castanheira M, Mendes RE, Toleman M, Walsh TR, Jones RN . Dissemination and diversity of metallo-beta-lactamases in Latin America: report from the SENTRY Antimicrobial Surveillance Program. Int J Antimicrob Agents 2005; 25: 57–61.
Tenover FC, Arbeit RD, Goering RV, Mickelsen PA, Murray BE, Persing DH, et al. Interpreting chromosomal DNA restriction patterns produced by pulsed-field gel electrophoresis: criteria for bacterial strain typing. J Clin Microbiol 1995; 33: 2233–9.
American Dietetic Association. Pediatric Nutrition Practice Group: Infant feedings: guidelines for preparation of formula and breast milk in healthcare facilities. Chicago; 2004.
Pejaver KR, Toonisi MA, Garg AK, al Hifzi I . Is expressed breast milk from home safe? A survey from a neonatal intensive-care unit. Infect Control Hosp Epidemiol 1996; 17: 346–7.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Mammina, C., Di Carlo, P., Cipolla, D. et al. Nosocomial colonization due to imipenem-resistant Pseudomonas aeruginosa epidemiologically linked to breast milk feeding in a neonatal intensive care unit. Acta Pharmacol Sin 29, 1486–1492 (2008). https://doi.org/10.1111/j.1745-7254.2008.00892.x
Received:
Accepted:
Issue date:
DOI: https://doi.org/10.1111/j.1745-7254.2008.00892.x
Keywords
This article is cited by
-
Outbreak investigations after identifying carbapenem-resistant Pseudomonas aeruginosa: a systematic review
Antimicrobial Resistance & Infection Control (2023)
-
Efficacy of a coordinated strategy for containment of multidrug-resistant Gram-negative bacteria carriage in a Neonatal Intensive Care Unit in the context of an active surveillance program
Antimicrobial Resistance & Infection Control (2021)


