Bacterial diversity in aortic aneurysms determined by 16S ribosomal RNA gene analysis

Herbaspirillum Species Bacteremia in a Pediatric Oncology Patient

“…It is a nitrogen-fixing soil and plant bacterium previously not considered a human pathogen (1, 3). Its close phylogenetic and phenotypic resemblance to Burkholderia cepacia complex has often resulted in misidentification (2,4). Although one of the earliest documented human infections with this organism was reported in 2005 from a wound isolate in a 49-year-old homeless man with a history of chronic liver disease (8), the advent of new technology has led to the reclassification as Herbaspirillum of previously identified and other, unclassified human isolates obtained as early as 1978 from infections of the ear, eye, knee, urine, oropharnyx, gastrointestinal tract, blood, and respiratory tract (2).…”

“…Although one of the earliest documented human infections with this organism was reported in 2005 from a wound isolate in a 49-year-old homeless man with a history of chronic liver disease (8), the advent of new technology has led to the reclassification as Herbaspirillum of previously identified and other, unclassified human isolates obtained as early as 1978 from infections of the ear, eye, knee, urine, oropharnyx, gastrointestinal tract, blood, and respiratory tract (2). Between 2000 and 2007, the Burkholderia cepacia Research Laboratory and Repository at the University of Michigan, Ann Arbor, isolated Herbaspirillum from 28 sputum cultures and one blood isolate referred from 23 cystic fibrosis (CF) treatment centers in the United States; 19 (68%) of the isolates had been initially identified as Burkholderia (4). Recent theories about infections contributing to aortic aneurysms led to the isolation of multiple organisms, including Herbaspirillum species, from aneurismal walls.…”

Molecular detection of transcriptionally active bacteria from failed prosthetic hip joints removed during revision arthroplasty

“…Shigella flexneri is a human intestinal pathogen which is known to invade the epithelium of the colon and it has been reported that this type of enteric bacterium may play a role in the exacerbation of disease in patients with enthesitis-related arthritis [45]. Caulobacter species show similar taxonomy to Brevundimonas species [46], so may belong to the same genera and, as already discussed, Brevundimonas as well as other bacterial species including Dermacoccus and Bradyrhizobium have been identified within aortic aneurysms by 16S rRNA gene sequencing [35]. Escherichia coli is one of the many species living in the intestine of humans and can cause intestinal and extra-intestinal infections, including urinary tract infections, meningitis, peritonitis, mastitis, septicaemia and gram-negative pneumonia [47].…”

“…Brevundimonas species are rarely isolated from clinical specimens and their role in human disease needs further investigation, although an association with two cases of bloodstream infections [33] and a case of septic arthritis in an immunocompetent child have been reported [34]. Brevundimonas and Dermacoccus species have also been identified by 16S rRNA gene sequencing as being part of a diverse range of bacterial species found in aortic aneurysms [35]. Conventional microbiological culture methods have also isolated Sphingomonas species in advanced noma lesions, infections which are open to the environment [36] and Peptoniphilus species have been isolated from human clinical specimens [37,38].…”

“…Other bacterial genera identified by both culture-dependent and culture-independent methods were Virgibacillus [30], Brevundimonas [33][34][35], Sphingomonas [36] and Peptoniphilus [37,38]. Members of the Virgibacillus genus are environmental bacteria that have never been associated with human infections, whereas all the other genera identified by both methods have been isolated from human clinical specimens.…”