title: Quantification of Bifidobacterium spp., Escherichia coli and Clostridium difficile in faecal samples of breast-fed and formula-fed infants by real-time PCR.
abstract: To determine the influence of either exclusive breast-feeding or formula feeding on both composition and quantity of the gut microbiota in infants, we have developed real-time, quantitative PCR assays for the detection of Bifidobacterium spp. and Clostridium difficile. Furthermore, we have monitored the prevalence and counts of Escherichia coli by applying a previously described real-time PCR assay. We found all 100 infants tested to be colonized by Bifidobacterium spp. The bifidobacterial counts were comparable between the 50 breast-fed and 50 formula-fed infants with median values of 10.56 log10 and 10.24 log10 CFU g(-1) wet weight faeces, respectively. C. difficile was detected in 14% of the breast-fed and 30% of the formula-fed infants. In addition, the C. difficile counts were significantly lower in breast-fed infants than in the formula-fed group (median values of 3.28 log10 and 7.43 log10 CFU g(-1), respectively; p=0.03). The prevalence of E. coli in the breast-fed and formula-fed group was 80% and 94%, respectively. Also, the E. coli counts in colonized infants was significantly lower in the breast-fed infants than in the formula-fed group (median values of 9.11 log10 and 9.57 log10 CFU g(-1), respectively; p=0.004). We conclude that the prevalence and counts of C. difficile as well as E. coli are significantly lower in the gut microbiota of breast-fed infants than in that of formula-fed infants, whereas the prevalence and counts of Bifidobacterium spp. is similar among both groups.
authors.affiliation: Department of Epidemiology, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, 6200 MD Maastricht, The Netherlands.
authors.forename: John
authors.initials: J
authors.lastname: Penders
authors.forename: Cornelis
authors.initials: C
authors.lastname: Vink
authors.forename: Christel
authors.initials: C
authors.lastname: Driessen
authors.forename: Nancy
authors.initials: N
authors.lastname: London
authors.forename: Carel
authors.initials: C
authors.lastname: Thijs
authors.forename: Ellen E
authors.initials: EE
authors.lastname: Stobberingh
mesh_terms: D001644:Bifidobacterium / Q000235:genetics / Q000302:isolation & purification; D001903:Bottle Feeding; D001942:Breast Feeding; D016360:Clostridioides difficile / Q000235:genetics / Q000302:isolation & purification; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D007225:Infant Food; D041943:Infant Formula / Q000008:administration & dosage; D008297:Male; D008895:Milk, Human; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity