The Microbiome in Connective Tissue Diseases and Vasculitides: An Updated Narrative Review

Table 1

Principal studies aiming to evaluate the alterations of microbiota in connective tissue diseases and vasculitides.

Author, year	Country	Models	Disease	Sample type	Technology employed	Implicated microbiota	Reference
Hevia et al., 2014	Spain	Human	SLE	Stool	16S rRNA (Ion Torrent PGM Sequencing, PCR analysis)	↓ Firmicutes/Bacteroidetes ratio in SLE pts than HC	[19]
He et al., 2016	China	Human	SLE	Stool	16S rRNA (Illumina Miseq)	↓ Firmicutes genera Dialister and Pseudobutyrivibrio; ↑ Bacteroidetes Rhodococcus, Eggerthella, Klebsiella, Prevotella, Eubacterium, Flavonifractor, and Incertae sedis	[20]
Corrêa et al., 2017	Brazil and USA	Human	SLE	Subgingival dental plaque samples	V4 region of 16S rRNA (Illumina MiSeq)	Higher bacterial loads and decreased microbial diversity; ↑ Fretibacterium, Prevotella nigrescens, and Selenomonas	[13]
Arron et al., 2014	USA	Human	SSc	Skin	Integrated Metagenomic Sequence Analysis, DNA microarrays, and 16S rRNA sequencing (Illumina HiSeq 2000)	No difference in bacterial microbiome between SSc and HC; ↑ Rhodotorula glutinis in SSc	[41]
Andréasson et al., 2016	Sweden	Human	SSc	Stool	The GA-map™ Dysbiosis Test	↓ Faecalibacterium and Clostridium in SSc than HC; More severe dysbiosis in pts with esophageal dysmotility, skin telangiectasias, pitting scars, pulmonary fibrosis, and elevated serum markers of inflammation	[35]
Volkmann et al., 2016	USA	Human	SSc	Cecum and sigmoid mucosal lavage samples	16S rRNA sequencing (Illumina HiSeq 2000)	↓ Faecalibacterium and Clostridium; ↑ Fusobacterium, g-Proteobacteria, Bifidobacterium and Lactobacillus; ↓ Bacteroides fragilis; ↑ Fusobacterium in SSc patients with moderate/severe GI tract symptoms	[36]
de Paiva et al., 2016	USA	Human and mice	SS	Conjunctival samples, tongue samples, stool	Human: Ocular conjunctiva: V1-V3 region of 16S rRNA; Tongue mucosa & stool: V4 region of 16S rRNA (454 Sequencing/Illumina Sequencing); Mice: Ready-To-Go™ You-Prime First-Strand kit	Mice stool: ↓ Blautia, Alistipes, Lactobacillus, Allobaculum, Bacteroides, Desulfovibrio, Intestinimonas, and Clostridium; ↑ Enterobacter, Parasutterella, Escherichia/Shigella, Pseudomonas, and Staphylococcus; Human stool: ↑ Pseudobutyrivibrio, Escherichia/Shigella, Blautia, and Streptococcus; ↓ Bacteroides, Parabacteroides, Faecalibacterium, Prevotella versus HC; Tongue samples: ↑ Streptococcus, ↓ Leptotrichia and Fusobacterium, ↓ Bergeyella, Peptococcus, and Butyrivibrio genera	[47]
Seoudi et al., 2015	UK	Human	BD	Saliva	Human oral microbe identification microarray (HOMIM) analysis	↑ Rothia denticariosa in BD and RAS ulcer sites; ↑ Streptococcus salivarius in ulcer sites in BD versus RAS; ↑ Streptococcus sanguinis in BD ulcer sites versus HC	[59]
Consolandi et al., 2015	Italy	Human	BD	Stool	Pyrosequencing of the V3-V4 hypervariable regions of the 16 rDNA gene and biochemical analysis	↓ Roseburia and Subdoligranulum than HC	[60]
Coit et al., 2016	Turkey, USA, and Sweden	Human	BD	Saliva	V4 region of 16S rRNA (Illumina Sequencing)	↑ Haemophilus parainfluenzae; ↓ Alloprevotella rava and species in the genus Leptotrichia	[58]
Shimizu et al., 2016	Japan	Human	BD	Stool	16S rRNA sequencing (Ion Torrent PGM)	↑ Bifidobacterium and Eggerthella; ↓ Megamonas and Prevotella genera in BD pts versus HC	[61]
Bhatt et al., 2014	USA	Human	GCA	Temporal artery biopsy specimens	Illumina HiSeq V3 sequencing	↑ Propionibacterium acnes and Escherichia coli in GCA and HC	[54]
Kinumaki et al., 2015	Japan	Human	KD	Stool	Metagenomic Shotgun Sequencing (Illumina Sequencing)	↑ Rothia, Staphylococcus, and Streptococcus in the acute phase; ↑Ruminococcus, Blautia, Faecalibacterium, and Roseburia in the nonacute phase	[55]

SLE: systemic lupus erythematosus; SSc: systemic sclerosis, GI: gastrointestinal; SS: Sjögren’s syndrome; BD: Behçet disease; RAS: recurrent aphthous stomatitis; GCA: giant cell arteritis; KD: Kawasaki disease; HC: healthy controls; pts: patients; PGM: personal genome machine; PCR: polymerase chain reaction; rRNA: ribosomal ribonucleic acid.