First Report of Kosakonia radicincitans Bacteraemia from Europe (Austria) - Identification and Whole-Genome Sequencing of Strain DSM 107547

Abstract

Kosakonia radicincitans is a species within the new genus Kosakonia. Many strains of this genus have been isolated from plants, but some strains are assumed to act as facultative human pathogens. in this study, an in-depth analysis of a Kosakonia isolate from human blood was performed. the strain was originally isolated from blood and identified as a member of the Enterobacter cloacae complex, exhibiting an atypical result in susceptibility testing. therefore, the genetic background was examined, including phylogenetic classification and screening for virulence factors. Using whole-genome sequencing, the isolate was identified as a K. radicincitans strain, revealing a virulence gene cluster for yersiniabactin biosynthesis in contrast to all other strains of the species. Whole-genome sequencing was the perfect method for identifying putative virulence factors of a particular Kosakonia strain and will help distinguish beneficial strains from pathogenic strains in the future. To our knowledge, this is the first report of Kosakonia-related bacteraemia from europe. Kosakonia radicincitans is a species within the new genus Kosakonia, until recently part of the genus Enterobacter. Many Kosakonia species have been isolated from plants and are known to improve plant performance 1,2 , but there are also rare reports that assume that some Kosakonia spp., such as Kosakonia cowanii, can act as facultative human pathogens 3. There are also rare reports of Kosakonia radicincitans involved in human infections; however, all these reports are from outside Europe (mainly Asia and America). The first case of a human bloodstream infection with K. radicincitans was reported in a 61-year-old man with cholangiocarcinoma in Houston, Texas, USA, in December 2016 4. However, the actual number of infections could have been underestimated, as this genus is relatively new and is therefore probably not yet included in all automated databases of bacterial diagnostic tools. It seems that Kosakonia has no higher pathogenic or resistance properties than Enterobacter, making a more precise diagnosis unnecessary in many cases 4. Therefore, this study used the rare opportunity to diagnose such an infection by careful evaluation. The aim of the study was to analyse the genetic background of a Kosakonia isolate from a patient with bacteraemia, including phylogenetic classification and screening for virulence factors. Description of the case: An 85-year-old woman presented at the Department of Internal Medicine, in Graz, Austria, with icterus, occasionally diffuse abdominal pain and loss of appetite. Upon admission, she was afebrile, showed atrial flutter (3:1), and a heart rate of 100/min; she was in slightly poor general condition and had pressure pain in the middle and lower abdomen. Her liver values were significantly increased. She was diagnosed with bile duct stenosis and received a stent by endoscopic retrograde cholangiopancreatography (ERCP) on the third day

Genomic Insight into Pediococcus acidilactici HN9, a Potential Probiotic Strain Isolated from the Traditional Thai-Style Fermented Beef Nhang

“…Furthermore, the probability of HN9 being a pathogen was assessed by pathogenicity factor analysis using PathogenFinder. The risk scores of the HN9 genome, plasmid pHN9-1, and pHN9-2 were 0.124, 0.209, and 0.174, respectively; these values are low for being considered as human pathogen compared to known probiotic strains such as Lactobacillus johnsonii ZLJ010 (0.193) [ 78 ], Lactobacillus casei DSM 20011 (0.198) [ 79 ], Lactobacillus reuteri PNW1 (0.217) [ 80 ], and known pathogens such as Kosakonia radicincitans DSM 107547 (0.71) [ 81 ] and Enterobacter sp. C6 (0.755) [ 82 ].…”

Bacteremia Due to Kosakonia cowanii in a Preterm Neonate

“…Many species from the Kosakonia genus (K. radicincitans, K. sacchari, K. oryzae, K. cowanii, and K. arachidis) have been isolated from plants, and only a few human infections have been described. 10 K. cowanii was first described from a patient sample but is mostly isolated from environmental samples, including soil and trees. K. cowanii may promote plant growth and can be identified as an endophyte in trees with symptoms of blight.…”

Novel Viruses That Lyse Plant and Human Strains of Kosakonia cowanii

“…There are also data describing the penetration of phages from the soil and their translocation ability in plant tissue [ 39 , 40 ], which open the door to the administration of curative phages by controlled irrigation or via hydroponic growth medium. Recently, K. cowanii and K. radicincitans species were documented to be facultative human pathogens causing bacteremia or cholecystitis [ 1 , 10 , 11 , 41 ]. Although such human infections seem to be rare, it is also probable they have been underestimated inasmuch as the pathogen could be misidentified as Enterobacter sp.…”

“…Although such human infections seem to be rare, it is also probable they have been underestimated inasmuch as the pathogen could be misidentified as Enterobacter sp. [ 10 , 11 ]. No preclinical trials have been performed for Kosakonia sp.…”

“…It was isolated from the intestine of Atlantic codfish ( Gadus morhua ) from the subpolar White Sea [ 9 ] and from nasal aperture of kea parrot ( Nestor notabilis ). In human, several strains of K. cowanii and K. radicincitans species have been isolated from clinical samples, including of blood, urine, bile, and sputum [ 2 , 10 , 11 ].…”