Hafnia, an enterobacterial genus naturally resistant to colistin revealed by three susceptibility testing methods

Jayol, Aurélie; Saly, Marion; Nordmann, Patrice; Ménard, Armelle; Poirel, Laurent; Dubois, Véronique

doi:10.1093/jac/dkx154

Cited by 30 publications

(28 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1). However, it is likely that the recent caveat that this microorganism be reclassified as constitutively resistant to colistin (19) may render in future the evaluation of colistin susceptibility for these strains redundant.…”

Section: Resultsmentioning

confidence: 99%

Clinical Validation of SensiTest Colistin, a Broth Microdilution-Based Method To Evaluate Colistin MICs

Carretto¹,

Brovarone²,

Russello³

et al. 2018

J Clin Microbiol

View full text Add to dashboard Cite

The global spread of multidrug-resistant Gram-negative bacteria has led to the return of colistin for treating severe infections. Recently, different plasmid-mediated genes conferring resistance to this drug were described and reported worldwide. International committees (EUCAST/CLSI) reevaluated inconsistencies surrounding colistin antimicrobial susceptibility testing (AST), concluding that broth microdilution (BMD) should serve as the reference method for AST. The development of an accurate, reproducible commercial test based on BMD is therefore highly desirable. SensiTest Colistin (STC), a BMD-based compact 4-test panel containing the lyophilized antibiotic in 7 2-fold dilutions (0.25 to 16 μg/ml) was here compared with the EUCAST-CLSI standard reference method (BMD) and, for some isolates, with the automated Phoenix 100 system (PHX). A total of 353 bacterial strains were evaluated by two different laboratories; 137 isolates were resistant to colistin (19 were intrinsically resistant, 83 harbored the gene). Essential agreement (EA) between STC and BMD was obtained for 339 out of the 353 strains tested (96.0%). Overall categorical agreement was obtained for 349 out of the 353 strains analyzed (98.9%). Two major errors (MEs; 0.93%) and two very major errors (VMEs; 1.46%) were documented. STC appeared to be a simple but highly reliable test with good reproducibility even with panels stored at room temperature or at 35°C. Moreover, STC showed a good performance with strains carrying the gene, with a 98.8% EA. As the secondary endpoint of our study, VMEs for PHX were documented for 6 isolates (10%).

show abstract

Section: Resultsmentioning

confidence: 99%

Clinical Validation of SensiTest Colistin, a Broth Microdilution-Based Method To Evaluate Colistin MICs

Carretto¹,

Brovarone²,

Russello³

et al. 2018

J Clin Microbiol

View full text Add to dashboard Cite

show abstract

“…Resistance to other antimicrobials was low among the Hafnia isolates, with the exception of AmpC mediated resistance to β-lactams (Table 3). As others have documented, the Bruker MALDI-TOF system cannot currently distinguish between the two Hafnia species: H. alvei and H. paralvei (Jayol et al, 2017). To determine which species these isolates belonged to, phenotypic testing using malonate assimilation and β-glucosidase activity was performed.…”

Section: Resultsmentioning

confidence: 99%

“…This genus is known to exhibit intrinsic resistance to polymyxins, and sequencing of 16S rRNA genes has revealed Hafnia to be phylogenetically related to other intrinsically colistin resistant members of the Enterobacteriales including Serratia spp. (Jayol et al, 2017). H. alvei was found as the most commonly isolated colistin-resistant organism from livestock in Switzerland, although it was not recovered from poultry, only from pigs and calves (Buess et al, 2017).…”

Section: Discussionmentioning

confidence: 99%

Polymyxin Resistant Bacteria in Australian Poultry

Bean

Wigmore

Momin

et al. 2020

Front. Sustain. Food Syst.

View full text Add to dashboard Cite

Resistance to last-resort antibiotics is significant public health issue. Antibiotic use in animal husbandry may be a driver of resistance that can subsequently be disseminated via the food chain. This study sought to determine the level of polymyxin resistance in Gram-negative pathogens present in Australian poultry, particularly the presence of mobilizable mechanisms of polymyxin resistance. Cloacal swabs from 213 birds were taken in a point prevalence survey from six different farms at a Victorian chicken processing facility. Colistin resistant organisms were recovered by direct plating on CHROMagar COL-APSE media. Bacterial isolates were identified and analyzed by MALDI-TOF, biochemical and genotypic assays. The 213 specimens yielded 57 (26.8%) colistin-resistant Gram-negative organisms, all of which have been previously described as exhibiting intrinsic resistance to polymyxin antibiotics. The most frequent organism was identified as Hafnia paralvei (40/57; 70%). Other colistin-resistant organisms included Aeromonas hydrophila (16%), Myroides odoratus (7%), Alcaligenes faecalis (5%), and Pseudochrobactrum spp. (2%). No mobile colistin resistance (mcr) genes were detected, although the arnA gene was identified in two A. hydrophila isolates and may mediate colistin resistance in these isolates. Intrinsic polymyxin-resistant organisms are widely distributed in the food chain, with over a quarter of the birds tested yielding a polymyxin-resistant organism. However, strains containing mcr genes remain rare in Australian poultry.

show abstract

“…One of each phenotypically different colony growing on SuperPolymyxin™ medium was subcultured on Columbia blood agar for species identification using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (Bruker, Bremen, Germany) applying the database MBT Compass 4.1. All intrinsically resistant species were removed from further susceptibility testing (e.g., Hafnia alvei, Morganella morganii, Proteus hauseri, Proteus vulgaris, Proteus mirabilis, Providencia rettgeri, Providencia stuarti, Providencia alcalifaciens, Serratia liquefaciens, Serratia marcescens, Serratia ureolytica ) (Magiorakos et al, 2012 ; Leclercq et al, 2013 ; Jayol et al, 2017 ; Saly et al, 2017 ) (Figure 1 ) . Stenotrophomonas maltophilia was excluded due to missing EUCAST breakpoints for colistin.…”

Section: Methodsmentioning

confidence: 99%

“…Colistin interacts with lipopolysaccharides on the outer membrane of Gram-negative bacteria and causes membrane damage leading to bacterial death (Grégoire et al, 2017 ). Some genera are intrinsically resistant to colistin (e.g., Burkholderia, Hafnia, Morganella, Proteus, Providencia, Serratia ) (Leclercq et al, 2013 ; Jayol et al, 2017 ). However, acquired colistin resistance has been reported, which is either encoded on the bacterial chromosome (e.g., mutations in lpxA, lpxC, lpxD, pmrA, pmrB, mgrB ), or on transferable plasmids (e.g., mcr-1–5 ) (Nordmann et al, 2016a ; Grégoire et al, 2017 ).…”

Section: Introductionmentioning

confidence: 99%

SuperPolymyxin™ Medium for the Screening of Colistin-Resistant Gram-Negative Bacteria in Stool Samples

et al. 2018

View full text Add to dashboard Cite

Colistin is one of the last resort antimicrobials for the treatment of infections caused by multidrug-resistant Gram-negative bacteria. After the emergence of transferable colistin resistance genes (mcr-1–5), a reliable culture-based screening method to detect colonization with colistin-resistant Gram-negative bacteria (CRGN) is needed. The objective of this study was to test the performance of SuperPolymyxin™ medium to screen for CRGN in stool samples and to compare different methods for the confirmation of colistin resistance (e.g., Etest®, broth microdilution [BMD], and the Rapid Polymyxin™ NP test). Colonization with CRGN was analyzed in a prospective cohort study among travelers. Stool samples (Fecal TranswabTM) taken before, during and after travel were cultured on SuperPolymyxin™ agar. Every phenotypically different colony was subcultured for species identification using MALDI-TOF mass spectrometry. Susceptibility to colistin was tested using Etest® and confirmed by BMD and the Rapid Polymyxin™ NP test. In total, 128 participants provided 1,495 stool samples. After culture on SuperPolymyxin™ medium (37°C, 24–48 h), 1,851 phenotypically different colonies were isolated. Isolates belonging to intrinsically colistin-resistant genera (e.g., Morganella, Providencia, Proteus) or Stenotrophomonas maltophilia were excluded from further analysis (n = 421). Among the remaining 1,430 isolates, colistin resistance was confirmed in 279 by Etest® (19.5%) and 218 by BMD (15.3%). The Rapid Polymyxin™ NP test was compared with BMD (reference) to detect colistin resistance (specificity: 88.6%, sensitivity 71.1%). SuperPolymyxin™ medium is suitable to screen for fecal colonization with CRGN. The high proportion of colistin-susceptible isolates growing on SuperPolymyxin™ medium caused a high workload. The confirmation of CRGN with the Rapid Polymyxin™ NP Test could be a less labor-intensive alternative to BMD.

show abstract

Hafnia, an enterobacterial genus naturally resistant to colistin revealed by three susceptibility testing methods

Abstract: The high rate of colistin resistance observed within the Hafnia genus and its close phylogenetic relationship with naturally colistin-resistant genera suggest that Hafnia is a naturally colistin-resistant enterobacterial genus.

Cited by 30 publications

References 14 publications

Clinical Validation of SensiTest Colistin, a Broth Microdilution-Based Method To Evaluate Colistin MICs

Clinical Validation of SensiTest Colistin, a Broth Microdilution-Based Method To Evaluate Colistin MICs

Polymyxin Resistant Bacteria in Australian Poultry

SuperPolymyxin™ Medium for the Screening of Colistin-Resistant Gram-Negative Bacteria in Stool Samples

Contact Info

Product

Resources

About