First Descriptions of bla _KPC in Raoultella spp. ( R. planticola and R. ornithinolytica ): Report from the SENTRY Antimicrobial Surveillance Program

Abstract

Two strains of Raoultella planticola and one of Raoultella ornithinolytica showing carbapenem resistance were recovered from patients hospitalized in New Jersey and Ohio. All patients had received previous antimicrobial treatment, including carbapenems. These strains harbored bla KPC-2 and bla KPC-3 . Carbapenemase genes were embedded in isoforms of Tn4401 and were plasmidic and chromosomal in location.Raoultella species are gram-negative aerobic bacilli belonging to the Enterobacteriaceae family that are closely related to Klebsiella spp. (7). These environmental organisms, infrequently causing human infections, appear to have pathogenicity similar to that of Klebsiella pneumoniae (8). The first human Raoultella spp. invasive infection was described in 1984, and bloodstream infections have been reported, though rarely (1). Studies have shown that 0.2 to 19.0% of isolates initially identified as Klebsiella spp. were Raoultella spp. by 16S rRNA analysis and that the prevalence of these organisms in clinical settings can vary geographically (8).(This work was presented at the 19th European Conference of Clinical Microbiology and Infectious Diseases, Helsinki, Finland, 2009.) A total of 7,248 Enterobacteriaceae isolates collected in medical centers from North America, Latin America, and Europe during 2008 were susceptibility tested by the reference broth microdilution method and interpretation criteria (3, 4). Isolates displaying imipenem and/or meropenem MICs of Ն2 g/ml were tested with the modified Hodge test (MHT) using imipenem and meropenem disks (4) and multiplex PCRs for the detection of carbapenemase-encoding genes, including bla IMP , bla VIM , bla KPC, bla SME , and bla GES variants and bla IMI , bla NMC-A , and bla .Among 134 (1.8% overall) isolates that were nonsusceptible to carbapenems, three (2.2%) Raoultella isolates from bloodstream infections were observed. MHT was positive for all three strains, and PCRs were positive for bla KPC . Sequencing of 16S rRNA revealed that two isolates were R. planticola (from Ohio and New Jersey) and one was R. ornithinolytica (from New Jersey). The isolates from New Jersey were detected in the same hospital and harbored bla , whereas the strain from Ohio carried bla KPC-2 . The clinical histories of the patients presenting infections with KPC-producing Raoultella spp. are summarized below. Case 1. An 83-year-old female patient was admitted to a hospital (Ohio) with a diagnosis of community-acquired bacterial pneumonia in May 2008. Sputum, paracentesis, and blood cultures were negative. Urine culture grew Escherichia coli, and the patient received courses of moxifloxacin, ceftriaxone, azithromycin, and meropenem. The patient was discharged and returned after 3 weeks with respiratory complaints. A tracheal-aspirate specimen grew a multidrug-resistant A. baumannii strain, and blood culture grew an enteric-like gram-negative bacillus (R. planticola). The patient subsequently died.Case 2. The patient was a 64-year-old man admitted to a hospital (New Jersey) in Septe...

Intestinal Carriage of Carbapenemase-Producing Organisms: Current Status of Surveillance Methods

“…KPC has been found in a variety of Enterobacteriaceae, including Klebsiella spp., Escherichia coli, Enterobacter spp., Citrobacter spp., Morganella spp., Serratia marcescens (25)(26)(27)(28)(29), Raoultella spp. (30), Kluyvera (31), and Salmonella (32), and in non-Enterobacteriaceae such as Aeromonas (33), Pseudomonas, and Acinetobacter baumannii (34).…”

Emergence of Raoultella ornithinolytica Coproducing IMP-4 and KPC-2 Carbapenemases in China

“…aoultella ornithinolytica is mostly recovered from the environment and rarely causes severe infections in humans; so far, only a few invasive R. ornithinolytica infections have been reported (1,2). Carbapenem resistance in Enterobacteriaceae represents one of the greatest problems in the realm of antibiotic resistance, and resistance is most often mediated by carbapenemases, such as Klebsiella pneumoniae carbapenemase (KPC), IMP, NDM, and OXA-48 (3).…”

“…However, the prevalence and molecular diversity of carbapenemases in Raoultella are largely unknown. Until now, the emergence of carbapenemases in the genus Raoultella has scarcely been described (1,(5)(6)(7).…”

Multiplex Real-Time PCR Assay for Detection and Classification of Klebsiella pneumoniae Carbapenemase Gene ( bla KPC ) Variants

“…(31), Salmonella enterica (22), Serratia marcescens (7), Citrobacter freundii (50), Proteus mirabilis (38), and most recently Raoultella spp. (8). The successive appear-ance of distinct bla KPC variants in different species is suggestive of adaptation in response to antibiotic pressure and highlights the ease with which plasmid-borne variants can spread among Enterobacteriaceae, thereby accelerating the global dissemination of carbapenem-resistant strains.…”