Table 2.
Summary of the most relevant research studies on the gut microbiome of patients with psoriasis.
| Author | Study Group | Analysed Sample | Method of Analysis | Results |
|---|---|---|---|---|
| Scher et al., 2015 [42] | Psoriasis patients (n = 15) Psoriatic arthritis patients (n = 16) Healthy controls (n = 17) |
Fecal sample | 16s rRNA sequencing (V1 -V2 hypervariable region) | ↓ diversity in psoriasis and psoriatic arthritis ↓ Bacteroidetes phylum in psoriasis versus psoriatic arthritis ↓ Akkermansia, Alistipes, Parabacteroides, Pseudobutyrivibrio, Ruminococcus and Coprococcus genera in psoriatic arthritis and psoriasis ↓ Coprobacillus genera in psoriasis when compared to psoriatic arthritis |
| Masallat et al., 2016 [58] | Psoriasis patients (n = 45) Healthy controls (n = 45) |
Fecal sample | Real-time PCR | ↓ Actinobacteria phylum ↑ Bifidobacterium Collinsella, Dorea Ruminococcus, Slackia and Subdoligranulum genera ↑ F/B ratio |
| Eppinga et al., 2016 [59] | Psoriasis patients (n = 29) IBD patients (n = 31) HS patients (n = 17)-Psoriasis and IBD patients (n = 13) HS and IBD patients (n = 17) Healthy controls (n = 33) |
Fecal sample | Quantitative PCR | ↓ F. prausnitzii ↑ E. coli in patients with psoriasis and concomitant psoriasis and IBD |
| Tan et al., 2018 [51] | Psoriasis patients (n = 14) Healthy controls (n = 14) | Fecal sample | 16s rDNA sequencing (V4 hypervariable region) | ↓ Akkermansia muciniphila, Verrucomicrobia and Tenericutes phyla Mollicutes and Verrucomicrobiae ↑ Bacteroides genera, Clostridium citroniae spp. and Enterococcus genera |
| Chen et al., 2018 [45] | Psoriasis patients (n = 32) Non-psoriasis controls (n = 64) |
Fecal sample | 16s rRNA sequencing (V3 - V4 hypervariable region) | ↑ Firmicutes ↓ Bacteroidetes ↑ F/B ratio ↓ Akkermansia genus |
| Hidalgo -Cantabrana et al., 2019 [60] | Psoriasis patients (n = 19) Healthy controls (n = 20) |
Fecal sample | 16s rRNA sequencing (V2 -V3 hypervariable region) | ↓ diversity ↑ Firmicutes ↓ Bacteroidetes ↑ F/B ratio ↑ Actinobacteria ↓ Proteobacteria phylum, Alistipes, Bacteroides, Barnesiella, Faecalibacterium, Parabacteroides and Paraprevotella genera |
| Shapiro et al., 2019 [50] | Psoriasis patients (n = 24) Non-psoriasis controls (n = 24) |
Fecal sample | 16s rRNA sequencing (V4 hypervariable region) | ↑ Firmicutes ↓ Bacteroidetes ↑ F/B ratio ↑ Actinobacteria phylum, Blautia and Faecalibacterium genera ↓ Proteobacteria phylum, Prevotella genarum, Ruminococcus gnavus, Dorea formicigenerans and Collinsella aerofaciens spp. |
| Zhang et al., 2021 [61] | Psoriasis patients (n = 30) Healthy controls (n = 30) |
Fecal sample | 16s rRNA sequencing | ↑ Faecalibacterium and Megamonas taxa |
| Valentini et al., 2021 [62] | Psoriasis patients treated with biologic therapy (n = 10) Psoriasis patients not treated with biologic therapy (n = 20) |
Fecal sample | 16s rRNA sequencing | ↓ diversity of biologically treated patients vs. untreated patients |
↓—decreased; ↑—increased; rRNA—ribosomal ribonucleic acid.