Characterization of Aerococcus viridans Isolates from Swine Clinical Specimens

Abstract

We present here the biochemical and genetic characterization and antimicrobial susceptibility of 58 isolates of Aerococcus viridans isolated in pure culture from different clinical specimens of normally sterile body sites of pigs. A. viridans isolates were commonly susceptible to ␤-lactam antimicrobials and exhibited a great genetic heterogeneity as determined by pulsed-field gel electrophoresis typing. The results indicate that A. viridans might be included in the list of possible etiological agents causing disease in pigs.The genus Aerococcus was initially described including a single species, Aerococcus viridans. Five new species of Aerococcus have been further identified: Aerococcus urinae, Aerococcus sanguinicola, Aerococcus christensenii, Aerococcus urinaeequi, and Aerococcus urinaehominis (6; http://www.bacterio .net). The clinical significance of these species has been clearly established for A. urinae and A. viridans. A. urinae is a rarely reported human pathogen that has been identified as responsible for urinary tract infections, septicemia, sepsis, endocarditis, or lymphadenitis (22)(23)(24)32). A. viridans has been associated with different human infections such as endocarditis, urinary tract infections, arthritis, or meningitis (7,10,13,20). Moreover, this species is a pathogen for crustaceans, causing gaffkemia in marine lobsters (1, 26), and it has been associated with septicemia in sea turtles (27). A. viridans has also been isolated from the milk of cows with subclinical mastitis (5) and has been associated with septicemia in immunodeficient mice (3); there have been no reports, as far as we know, of the isolation of this microorganism from other animal species. In the present study we report the isolation, biochemical and genetic characterization, and antimicrobial susceptibility of 58 isolates of A. viridans from different clinical specimens of pigs.According to the source of isolation, 30 isolates were obtained from the joints of pigs with arthritis, 14 isolates were obtained from the brains of pigs with meningitis, and 14 isolates were obtained from the lungs of pigs with pneumonia. All isolates were recovered in pure culture from individual animal samples in moderate to high numbers, which is indicative of their clinical significance and therefore likely to be associated with bacterial infection. Details of the clinical background of the A. viridans isolates included in the study are given in Table 1. Isolation of A. viridans isolates from clinical specimens was carried out on Columbia agar containing 5% of defibrinated sheep blood (bioMérieux España, s.a.) after incubation at 37°C for 24 h under aerobic and anaerobic conditions. All isolates were gram-positive catalase-negative cocci arranged in single cells, in pairs, in tetrads, or in small groups. The organisms were facultatively anaerobic and produced unpigmented, alpha-hemolytic, circular, colonies Ͻ1 mm in diameter after 24 h of incubation at 37°C on blood agar. Biochemical identification of A. viridans isolates was carried out by ...

Limited genetic diversity of Aerococcus viridans strains isolated from clinical and subclinical cases of bovine mastitis in Slovakia

“…The identity of ERIC1R generated PCR profiles clearly suggests that strains LK 13 and Str 13 from Liptovska Kokava or Budča farms are clonaly related. This observation is in contrast to data obtained by Martin et al (2007) who indicated an exposure of swine to multiple A. viridans strains, what is in accordance with the wide distribution of A. viridans (Woodward et al 1998), and also suggests an opportunistic pathogenic character of this bacterium. Similarly, Kagkli et al (2007) reported the presence of putative new A. viridans species in Gram-positive cocci from raw milk in a farm dairy environment.…”

“…Owens et al (1991) reported prevalent resistance to streptomycin (60%) followed by tetracycline (23%), erythromycin (17%), penicillin (16%) and ampicillin (13%). Completely different profiles were reported for A. viridans isolates from swine clinical specimens (Martin et al 2007). These A. viridans isolates were commonly susceptible to beta-lactam antimicrobials, but resistant to streptomycin (90%), tetracycline (95%) and erythromycin (59%).…”

Molecular Analysis of Bacterial and Circovirus Bioaerosols in Concentrated Animal Feeding Operations

“…Sequences closely related to the common opportunistic pathogen Aerococcus viridans, which is associated with arthritis in swine (Martin et al 2007), were found in all environments except the Swine A nursery. A. viridans has been cultured from environmental aerosol samples in previous studies (Williams et al 1953;Kerbaugh and Evans 1968).…”

Lactic Acid Bacteria Selection for Biopreservation as a Part of Hurdle Technology Approach Applied on Seafood

“…MICs values were similar to those found in our study with V. fluvialis CD264. Martín et al (2007) tested 58 A. viridans isolates for their susceptibility to 12 antimicrobials using the disk diffusion method. They found that A. viridans isolates were slightly resistant to streptomycin, erythromycin, clindamycin and tetracycline.…”

“…Kerbaugh and Evans (1968) also underlined such phenotype for A. viridans isolated from hospital environment. Moreover, A. viridans is a crustacean pathogen, causing the lobster's gaffkemia disease, and has been associated with different human infections such as endocarditis, urinary tract infections, arthritis, or meningitis (Kerbaugh and Evans, 1968;Martín et al, 2007).…”