title: Effects of probiotics on acquisition and spread of multiresistant enterococci.
abstract: Ampicillin-resistant Enterococcus faecium (ARE) and vancomycin-resistant E. faecium (VRE) are important nosocomial pathogens. We quantified effects of probiotics and antibiotics on intestinal acquisition of ARE colonization in patients hospitalized in two non-intensive care unit (non-ICU) wards with high ARE prevalence. In a prospective cohort study with crossover design, all patients with a length of stay of >48 h were offered a multispecies probiotic product twice daily until discharge (4.5 months, intervention period) or not (4.5 months, control period). Perianal ARE carriage was determined <48 h after admission, twice weekly, and <48 h before discharge. The first isolates were genotyped by multiple-locus variable-number tandem repeat analysis (MLVA). Risk factors for acquisition were determined by Cox proportional hazards modeling, with special emphasis on ecological postantibiotic effects and delays between actual acquisition and culture positivity. Of 530 patients included, 94 (18%) were ARE colonized on admission. Of the remaining 436 noncolonized patients, 92 acquired ARE colonization: 28 (25%) of 110 probiotic users and 64 (20%) of 326 control patients (chi(2) test, P = 0.325). In all, 661 ARE strains were isolated from 186 patients, of which 186 were genotyped. In both wards, two MLVA types (MTs; MT1 and MT159) were responsible for >80% of acquisitions. Both MTs were genetically different from the probiotic E. faecium strain. Antibiotics to which ARE is resistant (hazard ratio [HR], 7.73 [95% confidence interval (CI), 4.52 to 13.22]), an ecological postantibiotic effect (HR, 7.11 [95% CI, 3.10 to 16.30]), and age (HR, 1.01 [95% CI, 0.99 to 1.02]) were associated with ARE acquisition. The HR of probiotics was 1.43 (95% CI, 0.88 to 2.34). In a setting with high selective antibiotic pressure, probiotics failed to prevent acquisition of multiresistant enterococci.
authors.affiliation: Department of Medical Microbiology, University Medical Center Utrecht, G04.614, P.O. Box 85500, 3508 GA Utrecht, The Netherlands. m.deregt@umcutrecht.nl
authors.forename: Marieke J A
authors.initials: MJ
authors.lastname: de Regt
authors.forename: Rob J L
authors.initials: RJ
authors.lastname: Willems
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Hené
authors.forename: Peter D
authors.initials: PD
authors.lastname: Siersema
authors.forename: Harald J J
authors.initials: HJ
authors.lastname: Verhaar
authors.forename: Titia E M
authors.initials: TE
authors.lastname: Hopmans
authors.forename: Marc J M
authors.initials: MJ
authors.lastname: Bonten
mesh_terms: D000368:Aged; D000668:Ampicillin Resistance; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D016983:Enterococcus / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019936:Probiotics / Q000494:pharmacology*; D011446:Prospective Studies; D020713:Vancomycin Resistance
references.citation: Lancet. 2008 Feb 23;371(9613):651-659
references.pmid: 18279948
references.citation: PLoS Pathog. 2007 Jan;3(1):e7
references.pmid: 17257059
references.citation: Clin Infect Dis. 2000 Oct;31(4):1058-65
references.pmid: 11049790
references.citation: Clin Infect Dis. 2006 Jun 1;42(11):1552-60
references.pmid: 16652312
references.citation: J Int Med Res. 1983;11(1):28-31
references.pmid: 6219901
references.citation: Antimicrob Agents Chemother. 1991 Nov;35(11):2180-4
references.pmid: 1803989
references.citation: Curr Opin Gastroenterol. 2009 Jan;25(1):18-23
references.pmid: 19114770
references.citation: Clin Microbiol Infect. 2008 Apr;14(4):363-9
references.pmid: 18261124
references.citation: Clin Microbiol Infect. 2007 Mar;13(3):316-9
references.pmid: 17391388
references.citation: Am J Gastroenterol. 2008 Jan;103(1):178-89
references.pmid: 17900321
references.citation: J Antimicrob Chemother. 2008 Dec;62(6):1401-6
references.pmid: 18812427
references.citation: Med J Aust. 2007 May 7;186(9):454-7
references.pmid: 17484706
references.citation: Infect Control Hosp Epidemiol. 2008 Nov;29(11):996-1011
references.pmid: 18947320
references.citation: Lancet Infect Dis. 2001 Sep;1(2):101-14
references.pmid: 11871461
references.citation: N Engl J Med. 2000 Mar 9;342(10):710-21
references.pmid: 10706902
references.citation: J Infect Dis. 2000 May;181(5):1830-3
references.pmid: 10823795
references.citation: Antimicrob Agents Chemother. 2002 Jun;46(6):1619-28
references.pmid: 12019066
references.citation: Arch Intern Med. 1998 May 25;158(10):1127-32
references.pmid: 9605785
references.citation: BMJ. 2007 Jul 14;335(7610):80
references.pmid: 17604300
references.citation: Annu Rev Public Health. 1999;20:145-57
references.pmid: 10352854
references.citation: Curr Opin Microbiol. 2006 Oct;9(5):454-60
references.pmid: 16880002