Research

Oral probiotic and prevention of Pseudomonas aeruginosa infections: a randomized, double-blind, placebo-controlled pilot study in intensive care unit patients

Christiane Forestier¹ , Dominique Guelon² , Valérie Cluytens² , Thierry Gillart² , Jacques Sirot³ and Christophe De Champs⁴

¹Université de Clermont 1 UFR Pharmacie Laboratoire de Bactériologie, 28 place Henri Dunant 63000 Clermont-Ferrand France

²CHU Clermont-Ferrand, Hôpital Gabriel Montpied, Service de Réanimation médico-chirurgicale 63000 Clermont-Ferrand, France

³Université de Clermont 1 UFR Médecine CHU Clermont-Ferrand, Hôpital Gabriel Montpied Laboratoire de Bactériologie, 63000 Clermont-Ferrand France

⁴Laboratoire de Bactériologie-Virologie-Hygiène CHU Robert Debré de Reims and UFR Médecine Université Reims Champagne-Ardenne, 51092 REIMS France

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Critical Care 2008, 12:R69doi:10.1186/cc6907

Published:	20 May 2008

See related commentary by Morrow and Kollef, http://ccforum.com/content/12/3/160

Abstract

Introduction

Preventing carriage of potentially pathogenic micro-organisms from the aerodigestive tract is an infection control strategy used to reduce the occurrence of ventilator-associated pneumonia in intensive care units. However, antibiotic use in selective decontamination protocols is controversial. The purpose of this study was to investigate the effect of oral administration of a probiotic, namely Lactobacillus, on gastric and respiratory tract colonization/infection with Pseudomonas aeruginosa strains. Our hypothesis was that an indigenous flora should exhibit a protective effect against secondary colonization.

Methods

We conducted a prospective, randomized, double-blind, placebo-controlled pilot study between March 2003 and October 2004 in a 17-bed intensive care unit of a teaching hospital in Clermont-Ferrand, France. Consecutive patients with a unit stay of longer than 48 hours were included, 106 in the placebo group and 102 in the probiotic group. Through a nasogastric feeding tube, patients received either 10⁹ colony-forming units unity forming colony of Lactobacillus casei rhamnosus or placebo twice daily, from the third day after admission to discharge. Digestive tract carriage of P. aeruginosa was monitored by cultures of gastric aspirates at admission, once a week thereafter and on discharge. In addition, bacteriological analyses of respiratory tract specimens were conducted to determine patient infectious status.

Results

The occurrence of P. aeruginosa respiratory colonization and/or infection was significantly delayed in the probiotic group, with a difference in median delay to acquisition of 11 days versus 50 days (P = 0.01), and a nonacquisition expectancy mean of 69 days versus 77 days (P = 0.01). The occurrence of ventilator-associated pneumonia due to P. aeruginosa in the patients receiving the probiotic was less frequent, although not significantly reduced, in patients in the probiotic group (2.9%) compared with those in the placebo group (7.5%). After multivariate Cox proportional hazards modelling, the absence of probiotic treatment increased the risk for P. aeruginosa colonization in respiratory tract (adjusted hazard ratio = 3.2, 95% confidence interval – 1.1 to 9.1).

Conclusion

In this pilot study, oral administration of a probiotic delayed respiratory tract colonization/infection by P. aeruginosa.

Trial registration

The trial registration number for this study is NCT00604110.