After adjustment for confounders, this simple final DGGE model including only 2 bands (band 60.1 and band 45.9) remained

significantly associated with the API index (table 2). The accuracy of predicting asthma at the age of 3 years using this final DGGE model is shown in table 4. The model allows correct classification of 73% (80/110) of the cases. Table 4 Accuracy of final DGGE model* in predicting API status at age 3 years   API index   N     Pos Neg     DGGE model Pos. 13 19 32 PPV = 41% DGGE model Neg. 11 67 78 NPV = 86% Total 24 86 110     54% S 78% Sp   X2, p = 0.002 Overall correct classification: 80/110 = 73% API prevalence: 24/110 = 22% Final DGGE model: Positive: presence of band 60.1 (Clostridium coccoides subcluster XIVa) or band 45.9 (Bacteroides fragilis subgroup) Negative: absence of band 60.1 (Clostridium coccoides subcluster XIVa) and band 45.9 (Bacteroides fragilis subgroup) N: number of cases PPV: buy BI 10773 positive predictive value NPV: negative predictive value S: sensitivity Sp: specificity This means that, according to our findings, early intestinal colonization of infants with AG-881 cell line bacteria belonging to the Bacteroides fragilis group and/or to the Clostridium check details coccoides subcluster XIVa is associated with an increased risk for the development of asthma at the

age of 3 years. These bacteria are strict anaerobes and are part of the dominant genera of the normal intestinal microbiota observed in adults. We could not detect any bacterial taxa that were associated with health (API negative status).

Lactobacillus and Bifidobacterium, the bacterial genera generally used as probiotics and considered by definition of having a beneficial effect on health could not be associated with a reduced risk of asthma. However it cannot be excluded that our inability to demonstrate a beneficial effect of certain bacterial taxa on infant health was caused by the limited sensitivity of the DGGE method that we used. Discussion This study shows an association between early colonisation with a Bacteroides fragilis subgroup species and asthma later in life. We also showed in this study that a Clostridium coccoides subcluster XIVa species is an early indicator of asthma later in life. This is the first prospective study that links Clostridium coccoides subcluster XIVa to API, a clinically relevant risk Carnitine palmitoyltransferase II factor for developing asthma. Differences in feeding pattern, use of antibiotics, gender, maternal smoking in pregnancy or parental socio-economic status cannot explain the findings. Asthma is a frequently occurring condition in children with up to 50% of infants and children suffering of one or more episodes of wheezing below the age of 6 years. The diagnosis of asthma is not straightforward since no simple clinical tools are available to discriminate children prone to develop persistent asthma from those who will not. The ‘Asthma Prediction Index’ has been associated with an increased risk for asthma at school age [10].