Response by Anu Huurre, on behalf of the NAMI (Nutrition, Allergy, Mucosal Immunology and Intestinal Microbiota) research group

Abstract

With great interest, we have read the article by Huurre et al. [1] reporting on the impact of maternal atopy and probiotic supplementation during pregnancy on infant sensitization. We would like to comment on some of the results of this trial.First, the authors found an increased risk of sensitization in infants with allergic mothers breastfeeding over 6 months or exclusively breastfeeding over 2.5 months. Therefore, they conclude that breastfeeding in atopic mothers is a risk factor for sensitization in infants. However, these results may be biased, because of reversed causation [2]. The authors give no information regarding the prevalence of allergic disease, specifically atopic dermatitis, in the participating infants. It seems likely that the presence of allergic symptoms caused mothers to continue breastfeeding for a longer period of time, which could explain the observed relation between breastfeeding and increased sensitization.Second, considerable attention is given to the observation that TGF-b2 was higher in the probiotic than in the placebo group. However, this difference did not reach significance (CI, 0.96-2.34; P = 0.073). Moreover, this moderate effect was seen only in the colostrum sample and had totally disappeared after 1 month, despite that the probiotic supplementation was still continued at that time. Therefore, it is questionable if probiotic supplementation actually changed the breast milk cytokine pattern.Finally, we regret that no faecal samples of the mothers were analysed to confirm actual colonization with the given probiotic strains. This would have given important information on compliance. References 1 Huurre A, Laitinen K, Rautava S, Korkeamaki M, Isolauri E. Impact of maternal atopy and probiotic supplementation during pregnancy on infant sensitization: a double-blind placebo-controlled study. Clin Exp Allergy 2008; 38:1342-48. 2 Laubereau B, Brockow I, Zirngibl A et al. Effect of breast-feeding on the development of atopic dermatitis during the first 3 years of life-results from the GINI-birth cohort study. J Pediatr 2004; 144:602-7.Response by Anu Huurre, on behalf of the NAMI (Nutrition, Allergy, Mucosal Immunology and Intestinal Microbiota) research groupWe thank van der Aa et al. for their interest in our study, Impact of maternal atopy and probiotic supplementation during pregnancy on infant sensitization: A double-blind placebo-controlled study, evaluating possible factors explaining the protective effect of probiotics. The questions van der Aa et al. have brought up concerns the secondary outcomes, not the main outcome of the study, i.e. that the protective potential of the combination of Lactobacillus rhamnosus strain GG and Bifidobacterium lactis Bb12 was best seen in high risk group of infants.We agree with van der Aa et al. that the secondary outcomes may have received disproportionate attention in the final version; in the version originally submitted they were not equally emphasized. The reason why the reviewers wanted to stress these findings may be the fact that th...

Probiotic Therapy as a Novel Approach for Allergic Disease

“…For the combined prenatal/postnatal probiotic studies, there was a significant reduction in the cumulative incidence of eczema and/or IgE-associated eczema in six of the nine published RCTs (Kalliomaki et al, 2001b; Kukkonen et al, 2007; Wickens et al, 2008; Niers et al, 2009; Dotterud et al, 2010; Kim et al, 2010) by age 2 years. No such effects were reported in the other three studies (Abrahamsson et al, 2007; Huurre et al, 2008; Kopp et al, 2008). Interestingly, of these nine prenatal/postnatal studies, a beneficial effect was found in three of five studies that used LGG with or without other probiotics (LGG (Kalliomaki et al, 2001b); L. rhamnosus LC705, B. breve Bb99, and Propionibacterium freudenreichii + the prebiotic GOS (Kukkonen et al, 2007); LGG, L. acidophilus La-5 and B. lactis Bb12 (Dotterud et al, 2010).…”

“…While a paucity and evidence – mainly inconclusive – exists for the use of probiotics in the treatment of allergic disease, several clinical trials have been successful in the use of probiotics for the prevention of allergic disease. At present, a total of 14 randomized controlled trials evaluating various probiotics have been reported, mostly involving infants of families with a history of allergic disease (summarized in Table 4; Kalliomaki et al, 2001b; Rautava et al, 2006; Abrahamsson et al, 2007; Kukkonen et al, 2007; Taylor et al, 2007; Huurre et al, 2008; Kopp et al, 2008; Wickens et al, 2008; Niers et al, 2009; Soh et al, 2009; West et al, 2009; Dotterud et al, 2010; Kim et al, 2010; Boyle et al, 2011). …”

“…Interestingly, of these nine prenatal/postnatal studies, a beneficial effect was found in three of five studies that used LGG with or without other probiotics (LGG (Kalliomaki et al, 2001b); L. rhamnosus LC705, B. breve Bb99, and Propionibacterium freudenreichii + the prebiotic GOS (Kukkonen et al, 2007); LGG, L. acidophilus La-5 and B. lactis Bb12 (Dotterud et al, 2010). In the other two studies using LGG, one was a study in infants irrespective of a family history of allergic disease (Huurre et al, 2008) while the other study by Kopp et al (2008) found no effect despite utilizing a similar protocol and LGG dose to that of the landmark study by Kalliomaki et al (2001b). A recent meta-analysis of the impact of maternal probiotic supplementation on eczema development found a significantly reduced risk in children by 2–7 years of age with the use of lactobacilli but not with other probiotic species and strains compared to placebo treatment (Doege et al, 2012).…”