Is the effect of probiotics on allergic rhinitis confined to Dermatophagoides farinae, Dermatophagoides pteronyssinus, or dust-sensitive children? A randomized prospective double-blind controlled trial

ObjectiveProbiotics have previously been shown to reduce the severity of atopic disease in infants and children. However, the immunological changes induced by this treatment that might account for the clinical improvement are still unclear. In this study, we examined the effect of Lactobacillus rhamnosus on the clinical symptoms and medication use among children with established allergic rhinitis. We also investigated the effect of probiotics on the white blood cell counts, red blood cell counts, platelet counts, eosinophil counts, and IgE antibody levels.Materials and MethodsAtopic children with current rhinitis received 4 × 109 colony forming units/g of L rhamnosus (n = 98) or a placebo (n = 100). Both were given this daily as a powder mixed with food or water. The SCORing Allergic rhinitis index (specific symptoms scores and symptom medication scores), which measures of the extent and severity of allergic rhinitis, was assessed for each patient at the five visits. These five scheduled visits were at 2 weeks before starting the treatment (Visit 0), at the beginning of the treatment (Visit 1), then 4 weeks (Visit 2), 8 weeks (Visit 3), and 12 weeks (Visit 4) after starting the treatment. The white blood cell, red blood cell, platelet, and eosinophil counts as well as the IgE antibody levels of the individuals were evaluated before and after 3 months of treatment.ResultsThe major outcome, indicating the efficacy of L rhamnosus treatment, was no reduction in rhinitis symptoms or drug scores. No significant statistical differences were found between baseline and 3 months for the probiotic and placebo groups when any immunological and blood cell variable was examined.ConclusionsOur data demonstrates that L rhamnosus treatment neither reduced rhinitis symptom scores nor altered immunological parameters in symptomatic children.