''Aerococcus urinae'' is a

Gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bact ...

bacterium associated with

urinary tract infections A urinary tract infection (UTI) is an infection that affects part of the urinary tract. When it affects the lower urinary tract it is known as a bladder infection (cystitis) and when it affects the upper urinary tract it is known as a kidne ...

Classification

''Aerococcus urinae'' is a member of the

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...

l genus ''

Aerococcus ''Aerococcus'' is a genus in the phylum Bacillota (Bacteria). The genus was first identified in 1953 from samples of air and dust as a catalase-negative, gram-positive coccus that grew in small clusters. They were subsequently found in hospital ...

''. The bacterium is a Gram-positive, catalase-negative coccus growing in clusters. Isolates of this genus were originally isolated in 1953 from samples collected in the air and dust of occupied rooms and were distinguished by their tetrad cellular arrangements. Later, it was found in the urine of patients with

urinary tract infection A urinary tract infection (UTI) is an infection that affects part of the urinary tract. When it affects the lower urinary tract it is known as a bladder infection (cystitis) and when it affects the upper urinary tract it is known as a kidne ...

s and in 1992, ''A. urinae'' was assigned as distinct species. Due to difficulties in the biochemical identification of ''A. urinae'' in clinical microbiological laboratories, the incidence of infections with this bacterium has likely been underestimated and secure identification relies on genetic techniques like 16S ribosomal subunit sequencing or mass spectroscopic methods such as

MALDI-TOF In mass spectrometry, matrix-assisted laser desorption/ionization (MALDI) is an ionization technique that uses a laser energy absorbing matrix to create ions from large molecules with minimal fragmentation. It has been applied to the analysis of ...

Clinical relevance

''A. urinae'' may also cause invasive infections including urosepsis and infective

endocarditis Endocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves. Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or the ...

, especially in elderly men with underlying urinary tract diseases. ''A. urinae'' is sensitive to many commonly used antibiotics such as penicillin, cephalosporins, and vancomycin. Nitrofurantoin has been reported to be effective in one series of 42 clinical isolates. The bacterium can form biofilms on foreign materials and can aggregate human platelets, two features of potential importance for the disease causing capacity of this organism. ''A. urinae'' is the most common aerococcus isolated from invasive human infections whereas '' Aerococcus sanguinicola'' is isolated from human urine as often as ''A. urinae''.

References

External links

Type strain of ''Aerococcus urinae'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
Wikipedia articles with sections published in WikiJournal of Medicine Lactobacillales {{lactobacilli-stub