Bifidobacterium are considered a probiotic and commensal in the human gut, understood as nonpathogenic, however, there is at least one case report1 of this bacteria being a possible cause of a urinary tract infection. Bifidobacterium may be implicated as a pathogen in some circumstances.
What we know about bifidobacterium
- Anaerobic commensal of human intestine
- Part of healthy flora of the mouth and vagina
- Generally considered non-pathogenic
- Advocated as a probiotic
- Used to reduce diarrhoea
- May have caused sepsis and necrotising pancreatitis and urinary tract infections
- Over 30 species known
- Helps in normal bowel function
- Protects against gut infections
- Decreases gut inflammation
- Decreases symptoms of irritable bowel syndrome
- Implicated in case reports of necrotising pancreatitis, sepsis, epidural abscess, pulmonary infection and dental caries
- Other infections may have gone misdiagnosed due to commensal status
- Very slow to grow
- Difficult to identify, best to use rRNA gene sequencing
- May be misdiagnosed as Actinomyces spp.
- If isolated in large quantities from a specimen, should be considered causative agent of infection
- Bifidobacteria UTIs are rare, but have been identified
- Probiotics containing Bifidobacteria should be used carefully
References
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