Table 2.

Clinical relevance of human hosted Campylobacter species.

Campylobacter species	Isolation sites in human	Clinical relevance of human diseases	References
Campylobacter concisus	Healthy: saliva; subgingival site; intestinal biopsy; feces	Inflammatory bowel disease* Diarrheal diseases Barrett's esophagus* Periodontal disease	Tanner et al., 1981; Lindblom et al., 1995; Lastovica and Roux, 2000; Macuch and Tanner, 2000; Lastovica, 2006; Macfarlane et al., 2007; De Vries et al., 2008; Zhang et al., 2010; Kalischuk and Inglis, 2011; Mukhopadhya et al., 2011; Nielsen et al., 2011, 2013; Blackett et al., 2013; Mahendran et al., 2013; Zhang, 2015; Kirk et al., 2016
	IBD: saliva; intestinal biopsy Diarrhea: feces Barrett's esophagus: esophageal aspirate; distal esophageal biopsy Brain abscess: secondary to chronic frontal osteomyelitis Periodontal disease: subgingival site
Campylobacter curvus	Healthy: subgingival site	Gastroenteritis Abscess	Koga et al., 1999; Lastovica and Roux, 2000; Macuch and Tanner, 2000; Abbott et al., 2005; Petersen et al., 2007; De Vries et al., 2008; Mendz et al., 2014; Horio et al., 2017
	Periodontal disease: subgingival and periodontitis site Thoracic empyema: pleural effusion Premature birth: vaginal swabs Alveolar abscess Metastatic ovarian cancer: liver abscess Liver abscess: blood Lung cancer: bronchial abscess Guillain-Barré syndrome: feces Fisher's syndrome: feces Gastroenteritis: feces
Campylobacter gracilis	Healthy: subgingival site	Periodontal disease*	Tanner et al., 1981; Johnson et al., 1985; Yu and Chen, 1997; Macuch and Tanner, 2000; De Vries et al., 2008; Shinha, 2015
	Bacteraemia: blood Brain abscess (post-partum) Tubo-ovarian abscess Periodontal disease: subgingival and periodontitis site Visceral or head and neck infection
Campylobacter hominis	Healthy: feces	Septicaemia	Lawson et al., 1998, 2001; Linscott et al., 2005; Zhang et al., 2009
	Septicaemia: blood CD: intestinal biopsy
Campylobacter rectus	Healthy: subgingival site	Periodontal diseases* IBD	Von Troil-Lindén et al., 1995; Lastovica and Roux, 2000; Macuch and Tanner, 2000; Han et al., 2005; Macfarlane et al., 2007; De Vries et al., 2008; Mahlen and Clarridge, 2009; Zhang et al., 2009; Man et al., 2010b; López et al., 2011; Mukhopadhya et al., 2011; Lee et al., 2012; Leo and Bolger, 2014; Noël et al., 2018
	Periodontal disease: subgingival and periodontitis site Barrett's esophagus: distal esophageal mucosal biopsy Fatal thoracic empyema: pleural liquid Septic cavernous sinus thrombosis: blood Gastroesophageal adenocarcinoma: palate abscess Breast abscess Vertebral abscess Gastroenteritis: feces
Campylobacter showae	Healthy: subgingival site; gingival crevices	IBD	Etoh et al., 1993; Macuch and Tanner, 2000; De Vries et al., 2008; Zhang et al., 2009; Man et al., 2010b; Suzuki et al., 2013
	Periodontal disease: subgingival and periodontitis site CD: intestinal biopsy Intraorbital abscess Bacteraemia: blood
Campylobacter ureolyticus	Healthy: Male: urine Female: genital tract	IBD Gastroenteritis Genital tract diseae	Duerden et al., 1982, 1987, 1989; Johnson et al., 1985; Bennett et al., 1990, 1991; Petersen et al., 2007; Zhang et al., 2009; Bullman et al., 2011; Mukhopadhya et al., 2011; O'doherty et al., 2014
	CD: intestinal biopsy Gastroenteritis: feces Periodontal disease: deep periodontal pockets Superficial soft tissue or bone infections Male: Non-gonococcal, non-chlamydial urethritis Non-gonococcal urethritis Superficial necrotic or gangrenous lesions Penile wound Female: Perineal, genital and peripheral ulcers Genital tract: excess vaginal discharge; lower genital tract symptoms
	Health status unavailable: Amniotic fluid; urine

^*Campylobacter species that have established associations with human diseases or have been isolated from a sterile site.