Recovery of antimicrobial-resistant Pseudomonas aeruginosa from sputa of cystic fibrosis patients by culture on selective media

Perry, John D.; Laine, Larissa; Hughes, Susan M.; Nicholson, A.; Galloway, A.; Gould, F.K.

doi:10.1093/jac/dkn081

Cited by 19 publications

(21 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The author of this study concludes that in agreement with previous studies on the use of aerosolized combination therapy of tobramycin and azlocillin as well as the triple combination of tobramycin plus azlocillin and ticarcillin-clavulanic acid (Timentin), conventional measures of antimicrobial resistance may underestimate the clinical efficacy of tobramycin and colistin when delivered at the high concentrations achieved with the TSI formulation (320)(321)(322). These findings are in agreement with the poor predictability of clinical success by conventional susceptibility testing (31,79,80,(118)(119)(120)(121)(122)(123).…”

Section: Colistinsupporting

confidence: 87%

“…Basically, heteroresistance implies that the bacterial population in CF airways is significantly undersampled, resistance rates are underestimated, and there are subpopulations with different MICs. Therefore, routine susceptibility testing is not applicable, as the results are not representative of a heterogeneous population of P. aeruginosa (118). Consequently, data generated by routine methods are poorly predictive; ciprofloxacin susceptibility and resistance of a mixed-morphotype strain of P. aeruginosa from a CF patient were correctly predicted in 87.0% and 41.7% of cases, respectively (119), and another analysis revealed that the conventional approach of susceptibility testing indicated susceptibility in 45% of the isolates studied, although resistant subpopulations were identified by population analysis in all of these samples classified as being susceptible (120).…”

Section: Implications For Susceptibility Testingmentioning

confidence: 99%

“…Furthermore, conventional testing had no prognostic value for the clinical response to parenteral antibiotic treatment in CF patients (121,122). Consequently, routine susceptibility testing of CF pathogens is not representative, as the test provides a considerable underestimation of resistance (31,118) and has a limited prognostic value for clinical efficacy. Detection of heteroresistance would probably improve the situation.…”

Section: Implications For Susceptibility Testingmentioning

confidence: 99%

“…Detection of heteroresistance by, e.g., population analysis profiling is difficult and labor-intensive, so this method cannot be used under routine conditions. An alternative to conventional test methods could provide direct plating of sputum samples onto agar plates; direct plating increased the detection rate of resistant subpopulations to almost 100%, compared to ϳ40 to 60% with conventional testing (118,119,123).…”

Section: Implications For Susceptibility Testingmentioning

confidence: 99%

See 3 more Smart Citations

Pharmacokinetics and Pharmacodynamics of Aerosolized Antibacterial Agents in Chronically Infected Cystic Fibrosis Patients

Dalhoff¹

2014

Clin Microbiol Rev

View full text Add to dashboard Cite

SUMMARY Bacteria adapt to growth in lungs of patients with cystic fibrosis (CF) by selection of heterogeneously resistant variants that are not detected by conventional susceptibility testing but are selected for rapidly during antibacterial treatment. Therefore, total bacterial counts and antibiotic susceptibilities are misleading indicators of infection and are not helpful as guides for therapy decisions or efficacy endpoints. High drug concentrations delivered by aerosol may maximize efficacy, as decreased drug susceptibilities of the pathogens are compensated for by high target site concentrations. However, reductions of the bacterial load in sputum and improvements in lung function were within the same ranges following aerosolized and conventional therapies. Furthermore, the use of conventional pharmacokinetic/pharmacodynamic (PK/PD) surrogates correlating pharmacokinetics in serum with clinical cure and presumed or proven eradication of the pathogen as a basis for PK/PD investigations in CF patients is irrelevant, as minimization of systemic exposure is one of the main objectives of aerosolized therapy; in addition, bacterial pathogens cannot be eradicated, and chronic infection cannot be cured. Consequently, conventional PK/PD surrogates are not applicable to CF patients. It is nonetheless obvious that systemic exposure of patients, with all its sequelae, is minimized and that the burden of oral treatment for CF patients suffering from chronic infections is reduced.

show abstract

Section: Colistinsupporting

confidence: 87%

Section: Implications For Susceptibility Testingmentioning

confidence: 99%

Section: Implications For Susceptibility Testingmentioning

confidence: 99%

Section: Implications For Susceptibility Testingmentioning

confidence: 99%

See 2 more Smart Citations

Pharmacokinetics and Pharmacodynamics of Aerosolized Antibacterial Agents in Chronically Infected Cystic Fibrosis Patients

Dalhoff¹

2014

Clin Microbiol Rev

View full text Add to dashboard Cite

show abstract

“…It has been well recognised that the distribution of microorganisms in the CF lung is inhomogeneous. Hence, it is not surprising that, even for a single species, a wide distribution of MICs can exist [36,37].…”

Section: Local Concentrations Of Antibioticsmentioning

confidence: 99%

Inhaled antibiotics: dry or wet?

et al. 2014

View full text Add to dashboard Cite

Dry powder inhalers (DPIs) delivering antibiotics for the suppressive treatment of Pseudomonas aeruginosa in cystic fibrosis patients were developed recently and are now increasingly replacing time-consuming nebuliser therapy. Noninferiority studies have shown that the efficacy of inhaled tobramycin delivered by DPI was similar to that of wet nebulisation. However, there are many differences between inhaled antibiotic therapy delivered by DPI and by nebuliser. The question is whether and to what extent inhalation technique and other patient-related factors affect the efficacy of antibiotics delivered by DPI compared with nebulisers. Health professionals should be aware of the differences between dry and wet aerosols, and of patient-related factors that can influence efficacy, in order to personalise treatment, to give appropriate instructions to patients and to better understand the response to the treatment after switching.In this review, key issues of aerosol therapy are discussed in relation to inhaled antibiotic therapy with the aim of optimising the use of both nebulised and DPI antibiotics by patients. An example of these issues is the relationship between airway generation, structural lung changes and local concentrations of the inhaled antibiotics. The pros and cons of dry and wet modes of delivery for inhaled antibiotics are discussed. @ERSpublications Concentrations of inhaled antibiotics depend on airway generation, mode of delivery, disease severity and competence http://ow.ly/AJLs9

show abstract

Changes in cystic fibrosis sputum microbiology in the United States between 1995 and 2008

Emerson

McNamara

Buccat

et al. 2010

Pediatric Pulmonology

118

100

View full text Add to dashboard Cite

show abstract

Recovery of antimicrobial-resistant Pseudomonas aeruginosa from sputa of cystic fibrosis patients by culture on selective media

Cited by 19 publications

References 20 publications

Pharmacokinetics and Pharmacodynamics of Aerosolized Antibacterial Agents in Chronically Infected Cystic Fibrosis Patients

Pharmacokinetics and Pharmacodynamics of Aerosolized Antibacterial Agents in Chronically Infected Cystic Fibrosis Patients

Inhaled antibiotics: dry or wet?

Changes in cystic fibrosis sputum microbiology in the United States between 1995 and 2008

Contact Info

Product

Resources

About