Administration of Lactobacillus GG to hospitalised children reduces the risk of gastrointestinal and respiratory tract infections
- Correspondence to Mikki Meadows-Oliver
PO Box 9740, 100 Church Street South, Suite 200, Hamden, CT 06536-0740, USA;
Nosocomial or hospital-acquired infections have been associated with significant morbidity and mortality.1 They are a problem even in hospitals with above-average infection control programmes.2 On inpatient hospital units, paediatric patients have an increased risk for acquiring gastrointestinal and respiratory nosocomial infections. Such nosocomial infections have been shown to prolong hospital stays, worsen treatment outcomes and increase hospital costs.3 For these reasons, it is important to study interventions that may prevent nosocomial infections. Prevention methods that have been studied include hand hygiene and visitor screening, both of which have been shown to have little effectiveness in preventing nosocomial infections.3 The limited effectiveness of such interventions highlights the necessity for additional research in this area. One area that has recently been presented as a potential measure to prevent nosocomial infections is the use of probiotics. Probiotics are viable microorganisms that colonise the host and exert antibacterial and immunomodulatory effects.1
Probiotics and their effects on nosocomial infections
There have been few studiesthat have investigated the effectiveness of probiotics in the prevention of nosocomial infections.4 5 These studies have had conflicting results because of which researchers sought to investigate the role of the probiotic Lactobacillus GG (LGG) in the prevention of both respiratory and gastrointestinal nosocomial infections in the paediatric inpatient population. The study was conducted using a prospective, randomised, double-blind, placebo-controlled design. The study participants included 742 hospitalised paediatric patients. There were 376 participants in the treatment group and 366 participants in the placebo group. The treatment group received once-daily LGG at a dose of 109 colony forming units in 100 ml of fermented milk product. The control group received the same pasteurised milk product without LGG. No other prebiotic or probiotics were allowed during the study period.
Is LGG effective in reducing the risk for nosocomial infections?
Study findings revealed that the LGG treatment group had a significantly reduced risk for acquiring gastrointestinal and respiratory infections. Although there was a significantly decreased risk of developing a nosocomial infection among the participants in the treatment group, some patients did in fact develop a gastrointestinal or a respiratory nosocomial infection. For those that did, they were noted to have a significantly reduced duration of symptoms of infection compared with patients in the control group. The treatment group and the control group did not differ in terms of hospitalisation duration.
What does this study add?
Compared with other studies that researched the role of probiotics in the prevention of nosocomial gastrointestinal and respiratory infections in paediatric patients, this study included a broader age range (1–18 years) and had more participants than in the previous studies. These study findings suggest that the administration of LGG can be recommended as a valid measure to decrease the risk for both nosocomial respiratory and gastrointestinal infections in paediatric hospitals. However, the number needed to treat (NNT) (number of patients who need to be treated in order to prevent one additional adverse outcome) was relatively high. The NNT was 15 for gastrointestinal infections and 30 for respiratory infections. Therefore, this treatment may not be cost effective for all hospitalised children, but may be beneficial for those most at risk for developing severe complications related to nosocomial infections.
What should be the focus of future research?
Because of fermented cow's milk treatment, those younger than 1 year and those with milk allergies were excluded. Children younger than 1 year are prone to severe nosocomial infections and should be a population for future studies. There are still knowledge gaps regarding several factors associated with probiotics. These factors can also be the focus of future research questions: What are the mechanisms of action of different probiotics?; What are the most effective strains of probiotics for preventing infections (single or multiple strains)?; In what hospitalised populations are probiotics most cost effective?; What is the optimum dose and duration of treatment for prevention of nosocomial infections in paediatric patients? Future research on probiotics should also be conducted using a multicenter randomised controlled trial.