Impact of heteroresistance to colistin in meningitis caused by Acinetobacter baumannii

Rodríguez, Carlos Hernán; Barberis, Claudia; Nastro, Marcela; Bombicino, Karina; Granados, Gabriela; Vay, Carlos; Famiglietti, Ángela

doi:10.1016/j.jinf.2011.10.007

Cited by 14 publications

(13 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…According to our experience, to avoid selection of colistin resistance, combination therapy should also be used in non-heteroresistant cases. Therefore on this point, we contradict Rodriguez et al [23] who have previously compared colistin heteroresistant and nonheteroresistant ABC meningitis cases and found that colistin monotherapy was effective in non-heteroresistant cases.…”

Section: Discussioncontrasting

confidence: 65%

Investigation of Colistin Heteroresistance and Some Factors Affecting Heteroresistance in Carbapenem-Resistant A. baumannii Strains

Gazel¹,

Otkun²

2018

mjima

View full text Add to dashboard Cite

Introduction: Colistin can be used in patients infected with carbapenem-resistant Acinetobacter baumannii complex (CR-ABC), but recently resistance to colistin and heteroresistance have been reported. In this study we aimed to investigate the colistin heteroresistance rates and the effects of colistin and its combinations on colistin heteroresistance/resistance development in CR-ABC strains in our hospital. Materials and Methods: Heteroresistance analysis was performed on CR-ABC isolates and standard ABC strain [American Type Culture Collection (ATCC) 19606)] strain. To investigate hidden heteroresistance, the isolates were exposed to colistin at sub-inhibitory concentrations. 'Time-kill' study was performed on the standard strain and a clinical strain for colistin. Serial passage test was performed to investigate the effects of drug combinations on heteroresistance/resistance development. Results: In the first heteroresistance analysis test, all strains were found to be non-heteroresistant. However, after sub-inhibitory exposure to colistin, colistin heteroresistance/resistance developed in all isolates. In serial passages, colistin-rifampicin and colistin-tigecycline (Col+Tig) combinations were found to be effective and prevented growth of colistin-resistant sub-populations even at sub-inhibitory doses. Colistin-gentamicin (Col+Gen) combination was not found to be effective against the clinical isolate while it was effective on ATCC strain. Colistin-fluconazole combination was found to be ineffective at all concentrations. Conclusion: In our study, it was shown that the strains which were detected to be non-heteroresistant could easily transform to heteroresistant/ resistant forms after exposure to colistin. Colistin-rifampicin and Col+Tig combinations were found to be effective and prevented the emergence of heteroresistance/resistance to colistin even at low concentrations. At low concentrations, Col+Gen combination was ineffective against the clinical ABC isolate. Colistin-fluconazole combination failed to inhibit the emergence of resistant bacteria. Heteroresistance or resistance to colistin may easily develop because of inappropriate use of this antibiotic. To prevent this condition, colistin should be administrated at appropriate doses and in combination with the suggested antibiotics. Keywords: Colistin, carbapenem, combination, heteroresistance, rifampin Giriş: Kolistin, karbapenem dirençli Acinetobacter baumannii kompleks (CR-ABC) enfeksiyonu olan hastalarda kullanılabilecek seçeneklerdendir, ancak son zamanlarda kolistin için de direnç ve heterodirenç bildirilmiştir. Bu çalışmada hastanemizde izole edilen CR-ABC suşlarında, kolistin heterojen direnç oranını ve kolistinin ve bu ilacın ikili kombinasyonlarının kolistin heterodirenç/direnç gelişimi üzerine etkilerini araştırmayı amaçladık. Gereç ve Yöntem: Karbapenem dirençli A. baumannii izolatları vve standart ABC suşu [American Type Culture Collection (ATCC) 19606] üzerinde heterojen direnç analizi yapıldı. Gizli heterodirenç/direnci ortaya çıkarabil...

show abstract

Section: Discussioncontrasting

confidence: 65%

Investigation of Colistin Heteroresistance and Some Factors Affecting Heteroresistance in Carbapenem-Resistant A. baumannii Strains

Gazel¹,

Otkun²

2018

mjima

View full text Add to dashboard Cite

show abstract

“…In vitro synergy between rifampin and colistin has been shown previously ( 20 ). Rifampin has an excellent CSF penetration and was used for the treatment of meningitis caused by A. baumannii ( 2 , 22 ).…”

Section: Discussionsupporting

confidence: 61%

“…Nosocomial meningitis due to A. baumannii is fatal and its treatment is difficult ( 19 ). Recently, post neurosurgical meningitis caused by colistin heteroresistant A. baumannii has been reported ( 20 , 21 ). Due to difficulties in detection, the prevalence of colistin heteroresistance is not yet well understood and is not routinely used in most laboratories ( 9 , 21 ) but Overall, the colistin heteroresistance rate in A. baumannii was much higher than the resistance rate ( 9 ).…”

Section: Discussionmentioning

confidence: 99%

Post Neurosurgical Meningitis due to Colistin Heteroresistant Acinetobacter baumannii

Moosavian

Shoja

Nashibi

et al. 2014

Jundishapur J Microbiol

View full text Add to dashboard Cite

Introduction:Recently Acinetobacter baumannii isolates have emerged as a problematic infectious agent that causes meningitis in neurosurgical patients. Colistin has been used successfully for the treatment of A. baumannii meningitis but colistin resistant isolates have been reported worldwide.Case Presentation:Two isolates of A. baumannii were cultured during a five-day period from cerebrospinal fluid (CSF) samples of a 20-year-old man with a gunshot trauma in the abdomen, which had exited from his back. Antimicrobial susceptibility tests of isolates were performed. Multiplex PCR was performed for detection of blaOXA-23-like, blaOXA-24-like and blaOXA-58-like genes. Metallo-β-lactamase genes such as: blaVIM, blaIMP, blaSPM and blaNDM were sought by singleplex PCR. In order to evaluate the genetic relationship, two isolates were examined by the repetitive extragenic palindromic-polymerase chain reaction (REP_PCR) method.Conclusions:E-test results showed that the isolates were sensitive to colistin and tigecycline with minimum inhibitory concentration of (MIC) 0.25 µg/mL and 1.5 µg/mL, respectively. Secondly the isolates were resistant to colistin with MIC > 256 µg/mL but remained sensitive to tigecycline with MIC 1.5 µg/mL. On the basis of the multiplex PCR, both of the isolates were positive for blaOXA-23-like. Other investigated genes such as blaOXA-24-like, blaOXA-58-like, blaVIM, blaIMP, blaSPM and blaNDM were negative. REP-PCR results showed that two isolates were derived from a single strain and both were the same. The results of our study revealed that the firs isolate of A. baumannii was colistin heteroresistant and was changed to completely resistant during therapy. Diagnosis and treatment of A. baumannii meningitis is very important and to avoid treatment failure we suggest that all A. baumannii isolates obtained from CSF should be evaluated properly for colistin heteroresistance.

show abstract

“…Resistance to colistin in clinical isolates may go undetected when traditional in vitro antibiotic susceptibility testing is used, because of heteroresistance, which denotes the presence of subpopulations of bacterial cells with higher levels of antibiotic resistance than those of the rest of the population in the same culture (13). This phenomenon was described recently for Gram-negative organisms including Pseudomonas aeruginosa (14), Acinetobacter baumannii (15,16), and Enterobacter cloacae (17).…”

mentioning

confidence: 99%

Genomic Characterization of Colistin Heteroresistance in Klebsiella pneumoniae during a Nosocomial Outbreak

Halaby

Küçükköse

Janssen

et al. 2016

Antimicrob Agents Chemother

View full text Add to dashboard Cite

dKlebsiella pneumoniae is emerging as an important nosocomial pathogen due to its rapidly increasing multidrug resistance, which has led to a renewed interest in polymyxin antibiotics, such as colistin, as antibiotics of last resort. However, heteroresistance (i.e., the presence of a subpopulation of resistant bacteria in an otherwise susceptible culture) may hamper the effectiveness of colistin treatment in patients. In a previous study, we showed that colistin resistance among extendedspectrum-beta-lactamase (ESBL)-producing K. pneumoniae isolates emerged after the introduction of selective digestive tract decontamination (SDD) in an intensive care unit (ICU). In this study, we investigated heteroresistance to colistin among ESBL-producing K. pneumoniae isolates by using population analysis profiles (PAPs). We used whole-genome sequencing (WGS) to identify the mutations that were associated with the emergence of colistin resistance in these K. pneumoniae isolates. We found five heteroresistant subpopulations, with colistin MICs ranging from 8 to 64 mg/liter, which were derived from five clonally related, colistin-susceptible clinical isolates. WGS revealed the presence of mutations in the lpxM, mgrB, phoQ, and yciM genes in colistin-resistant K. pneumoniae isolates. In two strains, mgrB was inactivated by an IS3-like or ISKpn14 insertion sequence element. Complementation in trans with the wild-type mgrB gene resulted in these strains reverting to colistin susceptibility. The MICs for colistin-susceptible strains increased 2-to 4-fold in the presence of the mutated phoQ, lpxM, and yciM alleles. In conclusion, the present study indicates that heteroresistant K. pneumoniae subpopulations may be selected for upon exposure to colistin. Mutations in mgrB and phoQ have previously been associated with colistin resistance, but we provide experimental evidence for roles of mutations in the yciM and lpxM genes in the emergence of colistin resistance in K. pneumoniae.

show abstract

Impact of heteroresistance to colistin in meningitis caused by Acinetobacter baumannii

Cited by 14 publications

References 10 publications

Investigation of Colistin Heteroresistance and Some Factors Affecting Heteroresistance in Carbapenem-Resistant A. baumannii Strains

Investigation of Colistin Heteroresistance and Some Factors Affecting Heteroresistance in Carbapenem-Resistant A. baumannii Strains

Post Neurosurgical Meningitis due to Colistin Heteroresistant Acinetobacter baumannii

Genomic Characterization of Colistin Heteroresistance in Klebsiella pneumoniae during a Nosocomial Outbreak

Contact Info

Product

Resources

About