Background
Methods
Search strategy
Eligibility criteria and study selection
Quality appraisal
Data extraction and synthesis
Results
Characterisation of included studies
Methodological quality
Adverse events associated with IAP
Gut microbiota
Organism | Study | Number of infants (n) in each group | Relative abundance in microbiota composition (%) or number of infants (n) colonised | |||||
---|---|---|---|---|---|---|---|---|
Day 1 | Day 2 | Day 3 | Day 6/ 7 | Day 10 | Day 30 | |||
Phyla | ||||||||
All | Arboleya 2016 [33] | IAP n = 14 Control n = 13 | No differences | |||||
Actinobacteria
| Aloisio 2016 [31]a
| IAP n = 10 Control n = 10 | IAP: 0.4% Control: 3.8%
p < 0.05 | |||||
Arboleya 2016 [33] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | ||||||
Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 | IAP: 0% Control: 17%
p < 0.001 | ||||||
Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: 1% Control: 8%
RR 0.13 (CI 0.02-0.98)
| IAP: 7% | ||||||
Bacteriodetes
| Aloisio 2016 [31]a
| IAP n = 10 Control n = 10 | IAP: 16% Control: 47.7%
p < 0.05 | |||||
Mazzola 2016 [57]a
| Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: 21% Control: 36%
RR 0.59 (CI 0.3 –0.93)
| IAP: 34% Control: 26%
RR 1.31 (CI 0.85-2.01)
| |||||
Proteobacteria
| Aloisio 2016 [31]a
| IAP n = 10 Control n = 10 | IAP: 54.7% Control: 15.5%
p < 0.05 | |||||
Arboleya 2016 [33] | IAP n = 14 Control n = 13 | Higher % in IAP, p < 0.001 | ||||||
Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 | Higher % in IAP,
p < 0.062 | ||||||
Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: 37% Control: 17%
RR 2.18 (CI 1.32-3.60)
| IAP: 28% | ||||||
Firmicutes
| Arboleya 2016 [33] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.01 | |||||
Mazzola 2016 [57]a
| Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: 41% Control: 29%
RR 1.14 (CI 0.96-2.08)
| IAP: 30% | |||||
Family | ||||||||
Bifidobacteriaceae
| Aloisio 2016 [31]a
| IAP n = 10 Control n = 10 | IAP: 0.02% Control: 6.47%
p < 0.05 | |||||
Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | ||||||
Comamonadaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | |||||
Enterobacteriaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Higher % in IAP, p < 0.05 | |||||
Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 | Higher % in IAP,
p = 0.044 | IAP: 44% Control: 16%
RR 2.75 (CI 1.67-4.54)
| |||||
Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: 35% Control: 17%
RR 2.06 (CI 1.24-3.42)
| IAP: 28% | ||||||
Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP n = 13 Control n = 16
p = 0.58 | IAP: 0% | |||||
Lachnospiraceae
| Mazzola 2016 [57]a
| IAP n = 14 Control n = 13 | IAP: 4% | |||||
Leuconostaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | |||||
Micrococcaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | |||||
Propionibacteriaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | |||||
Staphylococcaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | |||||
Streptococcaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | |||||
Veillonellaceae
| Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 | Lower % in IAP, p = 0.035 | |||||
Unclassified Actinobacteria
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | |||||
Unclassified Bacilli
| IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | ||||||
Unclassified
Lactobacillales
| IAP n = 14 Control n = 13 | Lower % in IAP, p < 0.05 | ||||||
Genera | ||||||||
Bacteroides
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP n = 13 Control n = 7
p = 0.15 | |||||
Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 | IAP: 7% Control: 20%
p = 0.078 | ||||||
Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: 13% Control: 32%
RR 0.41 (CI 0.23-0.73)
| |||||||
Bifidobacteria
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP n = 6 Control n = 12
p = 0.18 | |||||
Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 | IAP: 0% Control: 16%
p = 0.001 | IAP: 6% (compared to day 7, p = 0.025) Control: 6% | |||||
Mazzola 2016 [57]a
| Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: 1% or 0% Control: 5% | IAP: 6% (compared to day 7, p = 0.013) Control: 19%
RR: 0.32 (CI 0.13-0.76)
| |||||
Clostridia
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP n = 3 Control n = 10
p = 0.04 | |||||
Enterococci
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP n = 15 Control n = 17
p = 0.73 | |||||
Escherichia
| Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 | IAP: 52% Control: 14%
RR 3.71 (CI 2.21-6.25)
| |||||
Staphylococci
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP n = 21 Control n = 22
p = 1.00 | |||||
Streptococci
| Mazzola 2016 [57]a
| Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: 32% Control: 10%
RR 3.2 (CI 1.66-6.15)
| IAP: 8% (compared to day 7, p = 0.042) | ||||
Other microbial genus | Aloisio 2016 [31]a
| IAP n = 10 Control n = 10 | No significant differences |
Organism | Study | Number of infants (n) in each group | Log colony forming units per gram (CFU/g) | |||
---|---|---|---|---|---|---|
Day 3 | Day 6/7 | Day 30 | Day 90 | |||
Family | ||||||
Staphylococcaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower log cells/g in IAP, p < 0.05 | |||
Enterobacteriaceae
| Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Higher log cells/g in IAP, p < 0.05 | |||
Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP: Md 8.4 (R 3.3-9.5) Control: Md 9.2 (R 3.3-9.8)
p = 0.18 | ||||
Genera | ||||||
Bacteroides
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP: Md 8.0 (R 6.3-10.3) Control: Md 7.9 (R 3.6-9.6)
p = 0.12 | |||
Bifidobacteria
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP: Md 8.2 (R 4.3-9.5) Control: Md 8.5 (R 6.9-10.3)
p = 0.10 | |||
Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Lower log cells/g in IAP, p < 0.05 | ||||
Bifidobacterium spp.
| Aloisio 2014 [30]a
| IAP n = 26 Control n = 26 | IAP: M 5.85 (R 3.24-7.79) Control: M 7.29 (R 4.12-10.95)
p = 0.001 | |||
Corvaglia 2016 [36]a
| IAP n = 35 Control n = 29 | IAP: Md 6.01 (IQR 5.51-6.98) Control: Md 7.80 (IQR 6.61-8.26)
p = 0.000 | IAP: Md 8.41 (IQR 7.71-8.80) Control: Md 8.39 (IQR 7.96-8.86) p = 0.363 | |||
Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 | IAP: Md 5.86 Control: Md 8.16
p = 0.005 | IAP: Md 7.72 (compared to day 7, p = 0.035) Control: Md 8.62 NS | |||
Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | IAP: Md 5.81 Control: Md 7.19
p = 0.03 | IAP: Md 8.50 (compared to day 7, p = 0.036) Control Md 8.55 (compared to day 7, p = 0.028) | ||||
Clostridia
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP: Md 5.3 (R 4.3-5.8) Control: Md 6.2 (R 3.6-8.1)
p = 0.01 | |||
Enterococci
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP: Md 8.3 (R 3.6-10.3) Control: Md 7.3 (R 3.3-9.5)
p = 0.78 | |||
Lactobacillus spp. | Aloisio 2014 [30]a
| IAP n = 26 Control n = 26 | IAP: M 6.69 (R 5.40-8.93) Control: M 6.73 (R 5.45-8.20) NS | |||
Corvaglia 2016 [36]a
| IAP n = 35 Control n = 29 | IAP: Md 5.56 (IQR 4.94-6.14) Control: Md 5.45 (IQR 4.81-6.14)
p = 0.872 | IAP: Md 5.29 (IQR 4.68–6.01) Control: Md 5.25 (IQR 4.60-6.15)
p = 0.932 | |||
Staphylococci
| Jaureguy 2004 [39]a
| IAP n = 25 Control n = 25 | IAP: Md 6.5 (R 3.6-8.0) Control: Md 7.0 (R 4.0-9.3)
p = 0.53 | |||
Species | ||||||
Escherichia coli
| Aloisio 2014 [30]a
| IAP n = 26 Control n = 26 | IAP: M 8.18 (R 4.09-12.70) Control: M 9.03 (R 5.61-11.78) NS | |||
Bacteroides fragilis
| Aloisio 2014 [30]a
| IAP n = 26 Control n = 26 | IAP: M 8.17 (R 4.68-11.99) Control: M 8.53 (R 5.22-11.16) NS | |||
Corvaglia 2016 [36]a
| IAP n = 35 Control n = 29 | IAP: Md 7.71 (IQR 5.80-9.33) Control: Md 7.75 (IQR 5.87-9.61)
p > 0.05 | IAP: Md 7.36 (IQR 5.80-9.09) Control: Md 8.51 (IQR 5.86-9.37)
p > 0.05 | |||
Clostridium difficile
| Aloisio 2014 [30]a
| IAP n = 26 Control n = 26 | IAP: M 3.89 (R 3.12-4.80) Control: M 3.70 (R 2.85-5.46) NS | |||
Total bacteria
| Mazzola 2016 [57]a
| Breast-fed IAP n = 7 Breast-fed Control n = 7 Mixed-fed IAP n = 6 Mixed-fed Control n = 6 | All groups: R 9.38-9.71 | All groups: R 9.53-9.83 | ||
Arboleya 2015 [32] | IAP n = 14 Control n = 13 | Higher log cells/g in IAP, p < 0.05 |