Table 1.
Studies characteristics and quality assessments of included studies.
| Study | CountryDesign | Sample size (male %) Age (yrs), mean ± SD | eGFR (ml/min·1.73m2) or Creatininea (umol/L) Urinary protein (g/24h, g/gb) | Matched factors | Stool sample collection and storage | DNA extraction method (Region Amplified) | Sequencing platformDatabase used | Outcomes:Alpha-diversity index;Beta-diversity;Microbiome analysis | NOS score | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
| IgAN | Healthy controls | IgAN | Healthy controls | ||||||||
| De Angelis et al. (2014) | Italy Cross-sectional study |
32 (66%) 43 ± 8 |
16 (60%) 43 ± 8 |
53 ± 28 0.59 ± 0.61 |
96 ± 7 0.05 ± 0.01 |
Age, gender | Fecal samples suspended in RNA later in sterile plastic box were stored at -80°C immediately | FastDNA Spin Kit for Soil 16S (V1-V3) |
454 FLX Sequencer USEARCH, RDP |
Observed sp., Chao1, Shannon; PCA; ANOVA |
9 |
| Zhong et al. (2020) | China Cross-sectional study |
52 (46.2%) 35.0 ± 9.1 |
25 (48.0%) 31.5 ± 5.4 |
90.4 (68.0-116.1) 1.85 ± 2.10 |
116.9 (114.0-125.9) 0.06 ± 0.03 |
Age, gender, dietary habits and lifestyle | Fresh fecal samples were placed in sterile containers and immediately stored at - 80°C | E.Z.N.A.® Soil DNA Kit 16S (V3-V4) |
Illumina MiSeq UPARSE, RDP, SILVA |
Observed sp., ACE, Chao1, Shannon, Simpson; PCoA; LEfSe, Wilcoxon rank-sum test, t-test |
8 |
| Dong et al. (2020) | China Cross-sectional study |
44 (45.5%) 34.89 ± 10.74 |
30 (46.7%) 38.60 ± 12.80 |
73.30 ± 23.94 0.77 (0.38–1.37) |
85.04 ± 18.24 NR |
Age, gender, BMI | Fresh fecal samples were immediately stored at −80°C | E.Z.N.A® Stool DNA kit 16S (V3-V4) |
Illumina MiSeq UPARSE, RDP, SILVA |
OTUs, ACE, Chao1, Shannon, Simpson; PCoA; LEfSe, Wilcoxon rank-sum test |
9 |
| Hu et al. (2020) | China Cross-sectional study |
17 (82.3%) 44.76 ± 10.53 |
18 (77.7%) 49.72 ± 8.39 |
83.16+32.49 0.95 ± 0.81b |
107.13+12.52 0.01 ± 0.001b |
Age, gender, BMI, dietary habits | Fresh fecal samples were placed in sterile harvesters and frozen at −80°C in no more than 30 min. | AxyPrep DNA Gel Extraction Kit 16S (V3-V4) |
Illumina HiSeq 2500 RDP |
Observed sp., ACE, Chao1, Shannon; PCoA, UniFrac; Wilcoxon rank sum test |
9 |
| Chai 2021 (Chai et al., 2021) | China Cross-sectional study |
29 (41.3%) 38.21 ± 11.80 |
29 (41.3%) 38.69 ± 9.90 |
101.95 (72.70, 123.44) 0.77 (0.36, 2.03) |
103.89 (99.40,114.34) NR |
Age, gender, BMI | Fresh fecal samples were collected in ice boxes, and transferred to -80°C within 30 min | PowerSoil® DNA Isolation Kit 16S (V3-V4) |
Ion S5TM
NR |
Observed sp., Chao1, Shannon, Simpson; NMDS; LEFSe |
9 |
| Wu et al. (2021) | China Cross-sectional study |
15 (46.6%) 38.64 ± 2.91 |
30 (66.6%) 44.1 ± 1.91 |
168.7 ± 61.26a
1.94 ± 0.44 |
75.43 ± 3.24a
NR |
Age, gender, BMI, dietary habits and lifestyles | Fecal samples were collected after overnight fasting, and stored at −80°C | PowerSoil DNA Isolation Kit 16S (V3-V4) |
Illumina HiSeq PE250 USEARCH, RDP |
OTUs, ACE, Chao1, Shannon, Simpson; PCoA; LEfSe, t-test |
8 |
| Sugurmar et al. (2021) | Malaysia Cross-sectional study |
36 (36.0%) 45.5 ± 13.4 |
12 (33.0%) 46.5 ± 13.5 |
79.0 (62.1, 92.2) 0.44 (0.20-1.13) |
86.5 (74.3, 93.8) 0.08 (0.08-0.08) |
Age, gender, BMI, dietary habits | Stool samples were taken at home and brought to hospital within 6 h in cold storage and were stored at -80°C | GeneAll ExgeneTM Stool DNA Kit 16S (V3-V4) |
Illumina NR QIIME RDP |
OTUs, Shannon; NR; t-test and Mann-Whitney test |
8 |
| He et al. (2021) | China Cross-sectional study |
Data set 1: 87 (52.87%) 38.78 ± 11.45 |
24 (50%) 35.79 ± 8.19 |
NR | NR | Age, gender, BMI | The fecal samples from each participant were collected in the hospital and immediately stored at -80°C | QIAamp Fast DNA stool minikit 16S (V3-V4) |
Illumina HiSeq UPARSEH, USEARCH, RDP |
Chao1; PCoA; Wilcoxon rank sum test |
9 |
| Data set 2: 27 (80.0%) 44.68 ± 12.65 |
19 (42.1%) 31.32 ± 10.59 |
Without selection | Illumina MiSeqDx UPARSEH, USEARCH, RDP |
7 | |||||||
| Weng et al. (2021) | China Cross-sectional study |
40 (57.5%) 35.12 ± 6.48 |
10 (60.0%) 35.26 ± 7.09 |
65.76 ± 30.24 1.85 ± 1.69 |
103.73 ± 21.01 0.06 ± 0.03 |
Age, gender, BMI | Fresh fecal samples were collected in sterile containers and immediately stored at - 80°C | HiPure Bacterial DNA Kit 16S (V3-V4) |
Illumina HiSeq4000 USEARCHGreenGene |
Observed sp., ACE, Chao1, Shannon, Simpson; PCoA, UniFrac; LefSe, t-test, and Mann-Whitney test |
9 |
| Ya et al. (2021) | China Cross-sectional study |
20 (50.0%) No difference in age |
20 (50.0%) Data not presented |
NR | NR | Age, gender | Fresh fecal samples were collected in cryogenic vials and immediately stored at - 80°C | FastDNA Spin Kit for Soil NR |
Illumina Hiseq2500 NR |
NR; NR; LefSe, t-test, and Wilcoxon rank sum test |
8 |
| Tian et al. (2021) | China Cross-sectional study |
10 (30%) 44.50 ± 8.54 |
10 (30%) 42.70 ± 11.96 |
72.12 ± 14.18a
1.51 ± 0.35 |
63.48 ± 10.90a
0.07 ± 0.04 |
Age, gender | Fresh fecal samples were collected in sterile containers and immediately stored at -80°C | NR 16S (V3-V4) |
Illumina Novaseq6000 UPARSE SILVA |
Observed sp., ACE, Chao1, Shannon, Simpson; PCoA; LefSe, t-test, and Mann-Whitney test |
8 |
SD, standard deviation; eGFR:estimated glomerular filtration rate; NR, not reported; BMI, body mass index; OTU, operational taxonomic units; Principal component analysis (PCA); PCoA, Principal coordinate analysis; NMDS, nonmetric multidimensional scaling; LEfSe, linear discriminant analysis effect size; UniFrac, analysis of similarity test; RDP, Ribosomal database project; QIIME, quantitative insights into microbial ecology; USEARCH,UPARSE, UPARSEH, SILVA: rRNA sequence databases. adata of serum creatinine; bdata of urinary albumin-to-creatinine ratio.