PURPOSE OF THE STUDY.
Previous studies have yielded conflicting data regarding the effects of probiotics on the prevention and treatment of allergic diseases. This prospective study examined the impact of dietary supplementation with Lactobacillus rhamnosus strain GG (ATCC 53103) on allergic sensitization, asthma, and atopic eczema.
Children (N = 131) between the ages of 6 and 24 months with a history of at least 2 physician-diagnosed episodes of wheezing within the previous year and a first-degree relative with atopic disease were recruited from a clinic of the Children's Hospital at Goethe University (Frankfurt, Germany) and were randomly assigned to double-blind supplementation with L rhamnosus or placebo twice daily for 6 months.
Clinical monitoring was performed before intervention and at 3, 6, 9, and 12 months. Outcome measures included the Severity Scoring of Atopic Dermatitis (SCORAD) index, asthma symptom scores defined by cough, wheeze, and need for intervention, and allergic sensitization. Serum samples were taken at 0, 6, and 12 months. Serum levels of egg, milk protein, lactalbumin, cat, horse, dust mite, birch, timothy, and Alternaria-specific immunoglobulin E were used as markers of allergic sensitization. Serum eosinophils, eosinophil cationic protein, and transforming growth factor β were also measured.
There were no significant differences in SCORAD indices or asthma-related events between the intervention and placebo groups. In a subgroup of patients with previous aeroallergen sensitization, asthma symptom scores were significantly lower in the placebo group. In a subgroup of patients with previous food-allergen sensitization, patients who received probiotics had fewer rescue-free days and required more inhaled β agonists. Cumulative levels of aeroallergen-specific immunoglobulin E were lower in patients assigned to probiotic supplementation. In the subgroup sensitized to aeroallergens, median eosinophil cationic protein values were lower in the probiotic group. Transforming growth factor β was significantly reduced in the probiotic group.
In young children with a history of recurrent wheeze and a family history of atopic disease, oral supplementation with L rhamnosus had mild negative effects on clinical respiratory status in children with antecedent allergic sensitization. Probiotic supplementation had no beneficial effects on atopic eczema. Probiotic supplementation was associated with mild changes in laboratory assessments of allergic sensitization.
In the current study, probiotic supplementation did not alleviate clinical symptoms of asthma or atopic eczema. In contrast, probiotic supplementation was associated with increased respiratory symptoms in patients with food and aeroallergen sensitivity. Potential confounders include increased exposure to tobacco smoke and increased respiratory symptoms before the study in the children randomly assigned to the probiotic group. Additional studies are required to assess probiotic use in children with a personal or family history of atopic disease.
- Copyright © 2011 by the American Academy of Pediatrics