1
|
Using machine learning to optimize antibiotic combinations: dosing strategies for meropenem and polymyxin B against carbapenem-resistant Acinetobacter baumannii. Clin Microbiol Infect 2020; 26:1207-1213. [PMID: 32061797 DOI: 10.1016/j.cmi.2020.02.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/28/2020] [Accepted: 02/05/2020] [Indexed: 12/18/2022]
Abstract
OBJECTIVES Increased rates of carbapenem-resistant strains of Acinetobacter baumannii have forced clinicians to rely upon last-line agents, such as the polymyxins, or empirical, unoptimized combination therapy. Therefore, the objectives of this study were: (a) to evaluate the in vitro pharmacodynamics of meropenem and polymyxin B (PMB) combinations against A. baumannii; (b) to utilize a mechanism-based mathematical model to quantify bacterial killing; and (c) to develop a genetic algorithm (GA) to define optimal dosing strategies for meropenem and PMB. METHODS A. baumannii (N16870; MICmeropenem = 16 mg/L, MICPMB = 0.5 mg/L) was studied in the hollow-fibre infection model (initial inoculum 108 cfu/mL) over 14 days against meropenem and PMB combinations. A mechanism-based model of the data and population pharmacokinetics of each drug were used to develop a GA to define the optimal regimen parameters. RESULTS Monotherapies resulted in regrowth to ~1010 cfu/mL by 24 h, while combination regimens employing high-intensity PMB exposure achieved complete bacterial eradication (0 cfu/mL) by 336 h. The mechanism-based model demonstrated an SC50 (PMB concentration for 50% of maximum synergy on meropenem killing) of 0.0927 mg/L for PMB-susceptible subpopulations versus 3.40 mg/L for PMB-resistant subpopulations. The GA had a preference for meropenem regimens that improved the %T > MIC via longer infusion times and shorter dosing intervals. The GA predicted that treating 90% of simulated subjects harbouring a 108 cfu/mL starting inoculum to a point of 100 cfu/mL would require a regimen of meropenem 19.6 g/day 2 h prolonged infusion (2 hPI) q5h + PMB 5.17 mg/kg/day 2 hPI q6h (where the 0 h meropenem and PMB doses should be 'loaded' with 80.5% and 42.2% of the daily dose, respectively). CONCLUSION This study provides a methodology leveraging in vitro experimental data, a mathematical pharmacodynamic model, and population pharmacokinetics provide a possible avenue to optimize treatment regimens beyond the use of the 'traditional' indices of antibiotic action.
Collapse
|
2
|
Brennan-Krohn T, Kirby JE. Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method. J Vis Exp 2019. [PMID: 31058886 DOI: 10.3791/58636] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
As rates of multidrug-resistant (MDR) pathogens continue to rise, outpacing the development of new antimicrobials, novel approaches to treatment of MDR bacteria are increasingly becoming a necessity. One such approach is combination therapy, in which two or more antibiotics are used together to treat an infection against which one or both of the drugs may be ineffective alone. When two drugs, in combination, exert a greater than additive effect, they are considered synergistic. In vitro investigation of synergistic activity is an important first step in evaluating the possible efficacy of drug combinations. Two main in vitro synergy testing methods have been developed: the checkerboard array and the time-kill study. In this paper, we present an automated checkerboard array method that makes use of inkjet printing technology to increase the efficiency and accuracy of this technique, as well as a standard manual time-kill synergy method. The automated checkerboard array can serve as a high-throughput screening assay, while the manual time-kill study provides additional, complementary data on synergistic activity and killing. The checkerboard array is a modification of standard minimum inhibitory concentration (MIC) testing, in which bacteria are incubated with antibiotics at different concentration combinations and evaluated for growth inhibition after overnight incubation. Manual performance of the checkerboard array requires a laborious and error-prone series of calculations and dilutions. In the automated method presented here, the calculation and dispensing of required antibiotic stock solution volumes are automated through the use of inkjet printer technology. In the time-kill synergy assay, bacteria are incubated with the antibiotics of interest, both together and individually, and sampled at intervals over the course of 24 h for quantitative culture. The results can determine whether a combination is synergistic and whether it is bactericidal, and provide data on inhibition and killing of bacteria over time.
Collapse
Affiliation(s)
- Thea Brennan-Krohn
- Department of Pathology, Beth Israel Deaconess Medical Center; Division of Infectious Diseases, Boston Children's Hospital; Harvard Medical School
| | - James E Kirby
- Department of Pathology, Beth Israel Deaconess Medical Center; Harvard Medical School;
| |
Collapse
|
3
|
Killing activity of meropenem in combination with amikacin against VIM- or KPC-producing Enterobacteriaceae that are susceptible, intermediate, or resistant to amikacin. Diagn Microbiol Infect Dis 2019; 93:372-375. [DOI: 10.1016/j.diagmicrobio.2018.10.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/30/2018] [Accepted: 10/31/2018] [Indexed: 11/23/2022]
|
4
|
Dundar D, Duymaz Z, Genc S, Er DK, İrvem A, Kandemir N. In-vitro activities of imipenem-colistin, imipenem-tigecycline, and tigecycline-colistin combinations against carbapenem-resistant Enterobacteriaceae. J Chemother 2019; 30:342-347. [PMID: 30663555 DOI: 10.1080/1120009x.2018.1516270] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The aim of the study is to determine in-vitro effects of imipenem-tigecycline, imipenem-colistin and tigecycline-colistin against carbapenem-resistant Enterobacteriaceae (CRE) isolates. A total of 25 CRE isolates were included to the study. The minimum inhibition concentrations of imipenem, colistin-sulphate and tigecycline were determined with broth dilution method. Synergistic effects of imipenem-tigecycline, imipenem-colistin and tigecycline-colistin were investigated by microdilution checkerboard technique. All of the isolates were resistant to imipenem, whereas 25% of the isolates were resistant to colistin and tigecycline. Imipenem-colistin, imipenem-tigecycline and tigecycline-colistin combinations were synergistic against 40% (10/25), 24% (6/25), and 36% (9/25) of the isolates, respectively. Antagonism was observed in 8% (2/25) of the isolates in tigecycline-colistin combination. Tigecycline-colistin was the most effective (70% synergy) combination in Klebsiella spp. strains; whereas imipenem-colistin was the most effective (75% synergy) combination in Escherichia coli strains. Synergistic effect was variable and strain-depended against CRE isolates that have been tested.
Collapse
Affiliation(s)
- Devrim Dundar
- a Department of Medical Microbiology, Faculty of Medicine , Kocaeli University , Turkey
| | - Zehra Duymaz
- a Department of Medical Microbiology, Faculty of Medicine , Kocaeli University , Turkey
| | - Serpil Genc
- a Department of Medical Microbiology, Faculty of Medicine , Kocaeli University , Turkey
| | - Doganhan Kadir Er
- b Department of Medical Microbiology, Institute of Health Sciences , Kocaeli University , Turkey
| | - Arzu İrvem
- c Department of Medical Microbiology , Istanbul Umraniye Training and Research Hospital , Turkey
| | - Neslisah Kandemir
- d Department of Molecular Biology and Genetics , Istanbul Technical University , Turkey
| |
Collapse
|
5
|
Holbrook SY, Garneau-Tsodikova S. Evaluation of Aminoglycoside and Carbapenem Resistance in a Collection of Drug-Resistant Pseudomonas aeruginosa Clinical Isolates. Microb Drug Resist 2018; 24:1020-1030. [PMID: 29261405 PMCID: PMC6154764 DOI: 10.1089/mdr.2017.0101] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Pseudomonas aeruginosa, a Gram-negative bacterium, is a member of the ESKAPE pathogens and one of the leading causes of healthcare-associated infections worldwide. Aminoglycosides (AGs) are recognized for their efficacy against P. aeruginosa. The most common resistance mechanism against AGs is the acquisition of AG-modifying enzymes (AMEs) by the bacteria, including AG N-acetyltransferases (AACs), AG O-phosphotransferases (APHs), and AG O-nucleotidyltransferases (ANTs). In this study, we obtained 122 multidrug-resistant P. aeruginosa clinical isolates and evaluated the antibacterial effects of six AGs and two carbapenems alone against all clinical isolates, and in combination against eight selected strains. We further probed for four representatives of the most common AME genes [aac(6')-Ib, aac(3)-IV, ant(2")-Ia, and aph(3')-Ia] by polymerase chain reaction (PCR) and compared the AME patterns of these 122 clinical isolates to their antibiotic resistance profile. Among the diverse antibiotics resistance profile displayed by these clinical isolates, we found correlations between the resistance to various AGs as well as between the resistance to one AG and the resistance to carbapenems. PCR results revealed that the presence of aac(6')-Ib renders these isolates more resistant to a variety of antibiotics. The correlation between resistance to various AGs and carbapenems partially reflects the complex resistance strategies adapted in these pathogens and encourages the development of strategic treatment for each P. aeruginosa infection by considering the genetic information of each isolated bacteria.
Collapse
Affiliation(s)
- Selina Y.L. Holbrook
- College of Pharmacy, Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky
| | - Sylvie Garneau-Tsodikova
- College of Pharmacy, Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky
| |
Collapse
|
6
|
Laishram S, Pragasam AK, Bakthavatchalam YD, Veeraraghavan B. An update on technical, interpretative and clinical relevance of antimicrobial synergy testing methodologies. Indian J Med Microbiol 2018; 35:445-468. [PMID: 29405135 DOI: 10.4103/ijmm.ijmm_17_189] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Testing for antimicrobial interactions has gained popularity in the last decade due to the increasing prevalence of drug-resistant organisms and limited options for the treatment of these infections. In vitro combination testing provides information, on which two or more antimicrobials can be combined for a good clinical outcome. Amongst the various in vitro methods of drug interactions, time-kill assay (TKA), checkerboard (CB) assay and E-test-based methods are most commonly used. Comparative performance of these methods reveals the TKA as the most promising method to detect synergistic combinations followed by CB assay and E-test. Various combinations of antimicrobials have been tested to demonstrate synergistic activity. Promising results were obtained for the combinations of meropenem plus colistin and rifampicin plus colistin against Acinetobacter baumannii, colistin plus carbapenem and carbapenem plus fluoroquinolones against Pseudomonas aeruginosa and colistin/polymyxin B plus rifampicin/meropenem against Klebsiella pneumoniae. Antagonism was detected in only few instances. The presence of synergy or antagonism with a combination seems to correlate with minimum inhibitory concentration of the agent and molecular mechanism involved in the resistance. Further studies need to be conducted to assess the utility of in vitro testing to predict clinical outcome and direct therapy for drug-resistant organisms.
Collapse
Affiliation(s)
- Shakti Laishram
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu,, India
| | - Agila Kumari Pragasam
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu,, India
| | | | - Balaji Veeraraghavan
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu,, India
| |
Collapse
|
7
|
In Vitro Antibacterial Interaction of Doripenem and Amikacin against Multidrug-Resistant Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae Isolates. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2018; 2018:1047670. [PMID: 30065794 PMCID: PMC6051294 DOI: 10.1155/2018/1047670] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 05/21/2018] [Accepted: 05/29/2018] [Indexed: 12/02/2022]
Abstract
Evaluation of the in vitro interaction of doripenem and amikacin against Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae was done by classifying them into four groups: doripenem and amikacin sensitive (DOR-S/AMK-S), doripenem sensitive and amikacin resistant (DOR-S/AMK-R), doripenem resistant and amikacin sensitive (DOR-R/AMK-S), and both doripenem and amikacin resistant (DOR-R/AMK-R). The MIC of each antibiotic and their combination was obtained using the Etest method. The fractional inhibitory concentration index was calculated to classify the results as synergistic, additive, indifferent, or antagonistic interaction. In the DOR-S/AMK-S class, 1 isolate of A. baumannii showed synergy and the other 5 showed additive results, 5 isolates of P. aeruginosa showed additive and 1 isolate showed indifferent result, and 2 isolates of K. pneumoniae showed additive and the other 4 showed indifferent results. In the DOR-S/AMK-R class, 3 isolates of A. baumannii showed additive and the other 3 showed indifferent results, 2 isolates of P. aeruginosa showed indifferent results, and 1 isolate of K. pneumoniae showed additive and the other 5 showed indifferent results. In the DOR-R/AMK-S class, 1 isolate of A. baumannii showed additive and the other 5 showed indifferent results, 1 isolate of P. aeruginosa showed additive and the other 5 showed indifferent results, and 4 isolates of K. pneumoniae showed additive and the other 2 showed indifferent results. In the DOR-R/AMK-R class, 6 isolates of A. baumannii showed indifferent results, 1 isolate of P. aeruginosa showed additive and the other 5 showed indifferent results, and 1 isolate of K. pneumoniae showed additive and the other 5 showed indifferent results. Synergy occurred in only 1 (1.5%) isolate. Additive interaction occurred in 24 (35.3%) isolates, and indifferent interaction occurred in 43 (63.2%) isolates. Doripenem sensitive combined with amikacin sensitive reduced MIC significantly in all bacterial isolates when compared to single MIC of each antibiotic.
Collapse
|
8
|
Brennan-Krohn T, Truelson KA, Smith KP, Kirby JE. Screening for synergistic activity of antimicrobial combinations against carbapenem-resistant Enterobacteriaceae using inkjet printer-based technology. J Antimicrob Chemother 2018; 72:2775-2781. [PMID: 29091221 DOI: 10.1093/jac/dkx241] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 06/15/2017] [Indexed: 11/14/2022] Open
Abstract
Background Synergistic combination antimicrobial therapy may provide new options for treatment of MDR infections. However, comprehensive in vitro synergy data are limited and facile methods to perform synergy testing in a clinically actionable time frame are unavailable. Objectives To systematically investigate a broad range of antibiotic combinations for evidence of synergistic activity against a collection of carbapenem-resistant Enterobacteriaceae (CRE) isolates. Methods We made use of an automated method for chequerboard array synergy testing based on inkjet printer technology in the HP D300 digital dispenser to test 56 pairwise antimicrobial combinations of meropenem, aztreonam, cefepime, colistin, gentamicin, levofloxacin, chloramphenicol, fosfomycin, trimethoprim/sulfamethoxazole, minocycline and rifampicin, as well as the double carbapenem combination of meropenem and ertapenem. Results In a screening procedure, we tested these combinations against four CRE strains and identified nine antibiotic combinations that showed potential clinically relevant synergy. In confirmatory testing using 10 CRE strains, six combinations demonstrated clinically relevant synergy with both antimicrobials at the minimum fractional inhibitory concentration (FICI-MIN) in the susceptible or intermediate range in at least one trial. These included two novel combinations: minocycline plus colistin and minocycline plus meropenem. In 80% of strains at least one combination demonstrated clinically relevant synergy, but the combinations that demonstrated synergy varied from strain to strain. Conclusions This work establishes the foundation for future systematic, broad-range investigations into antibiotic synergy for CRE, emphasizes the need for individualized synergy testing and demonstrates the utility of inkjet printer-based technology for the performance of automated antimicrobial synergy assays.
Collapse
Affiliation(s)
- Thea Brennan-Krohn
- Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, USA
| | - Katherine A Truelson
- Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Boston University, Boston, MA, USA
| | - Kenneth P Smith
- Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - James E Kirby
- Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA, USA
| |
Collapse
|
9
|
Park GC, Choi JA, Jang SJ, Jeong SH, Kim CM, Choi IS, Kang SH, Park G, Moon DS. In Vitro Interactions of Antibiotic Combinations of Colistin, Tigecycline, and Doripenem Against Extensively Drug-Resistant and Multidrug-Resistant Acinetobacter baumannii. Ann Lab Med 2017; 36:124-30. [PMID: 26709259 PMCID: PMC4713845 DOI: 10.3343/alm.2016.36.2.124] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 10/01/2015] [Accepted: 11/11/2015] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Acinetobacter baumannii infections are difficult to treat owing to the emergence of various antibiotic resistant isolates. Because treatment options are limited for multidrug-resistant (MDR) A. baumannii infection, the discovery of new therapies, including combination therapy, is required. We evaluated the synergistic activity of colistin, doripenem, and tigecycline combinations against extensively drug-resistant (XDR) A. baumannii and MDR A. baumannii. METHODS Time-kill assays were performed for 41 XDR and 28 MDR clinical isolates of A. baumannii by using colistin, doripenem, and tigecycline combinations. Concentrations representative of clinically achievable levels (colistin 2 μg/mL, doripenem 8 μg/mL) and achievable tissue levels (tigecycline 2 μg/mL) for each antibiotic were used in this study. RESULTS The colistin-doripenem combination displayed the highest rate of synergy (53.6%) and bactericidal activity (75.4%) in 69 clinical isolates of A. baumannii. Among them, the-doripenem-tigecycline combination showed the lowest rate of synergy (14.5%) and bactericidal activity (24.6%). The doripenem-tigecycline combination showed a higher antagonistic interaction (5.8%) compared with the colistin-tigecycline (1.4%) combination. No antagonism was observed for the colistin-doripenem combination. CONCLUSIONS The colistin-doripenem combination is supported in vitro by the high rate of synergy and bactericidal activity and lack of antagonistic reaction in XDR and MDR A. baumannii. It seems to be necessary to perform synergy tests to determine the appropriate combination therapy considering the antagonistic reaction found in several isolates against the doripenem-tigecycline and colistin-tigecycline combinations. These findings should be further examined in clinical studies.
Collapse
Affiliation(s)
- Gyun Cheol Park
- Department of Laboratory Medicine, College of Medicine, Chosun University, Gwangju, Korea
| | - Ji Ae Choi
- Research Center for Resistant Cells, College of Medicine, Chosun University, Gwangju, Korea
| | - Sook Jin Jang
- Department of Laboratory Medicine, College of Medicine, Chosun University, Gwangju, Korea.,Research Center for Resistant Cells, College of Medicine, Chosun University, Gwangju, Korea.
| | - Seok Hoon Jeong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea.
| | - Choon-Mee Kim
- Premedical Science, College of Medicine, Chosun University, Gwangju, Korea
| | - In Sun Choi
- Department of Laboratory Medicine, College of Medicine, Chosun University, Gwangju, Korea
| | - Seong Ho Kang
- Department of Laboratory Medicine, College of Medicine, Chosun University, Gwangju, Korea
| | - Geon Park
- Department of Laboratory Medicine, College of Medicine, Chosun University, Gwangju, Korea
| | - Dae Soo Moon
- Department of Laboratory Medicine, College of Medicine, Chosun University, Gwangju, Korea
| |
Collapse
|
10
|
So W, Crandon JL, Hamada Y, Nicolau DP. Antibacterial activity of achievable epithelial lining fluid exposures of Amikacin Inhale with or without meropenem. J Antimicrob Chemother 2015; 71:428-37. [PMID: 26559690 DOI: 10.1093/jac/dkv370] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 10/11/2015] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES While Amikacin Inhale (BAY41-6551), an integrated drug-device combination under development, achieves an estimated amikacin epithelial lining fluid (ELF) concentration of ∼ 5000 mg/L, its target site pharmacodynamics are unknown. We evaluated the pharmacodynamics of ELF exposure of inhaled amikacin ± meropenem. METHODS ELF exposures of inhaled amikacin (400 mg every 12 h), intravenous meropenem (2 g every 8 h) and a combination of both were studied in an in vitro pharmacodynamic model. Seven Klebsiella pneumoniae and 10 Pseudomonas aeruginosa with amikacin/meropenem MICs of 1 to 32,768/≤ 0.125 to >128 mg/L were included. Efficacy was assessed over 24-72 h. RESULTS The mean ± SD 0 h bacterial density was 6.5 ± 0.1 log10 cfu/mL. Controls grew to 8.0 ± 0.5 log10 cfu/mL by the end of the experiments. Simulation of inhaled amikacin monotherapy rapidly achieved and sustained bactericidal activity near the limit of detection over 24 h for all 13 isolates with amikacin MIC ≤ 256 mg/L except only ∼ 2 log10 cfu/mL reduction was observed in K. pneumoniae 375 (amikacin/meropenem MIC 64/32 mg/L) and P. aeruginosa 1544 (amikacin/meropenem MIC 64/128 mg/L). No activity was seen against the three isolates with amikacin MIC ≥ 2048 mg/L. Among the six isolates tested with meropenem monotherapy, five (meropenem MIC ≥ 16 mg/L) grew similarly to the controls while one (meropenem MIC 2 mg/L) achieved ∼ 2.5 log10 cfu/mL decrease. Among seven isolates tested in combination, four (amikacin/meropenem MIC ≤ 64/32 mg/L), including K. pneumoniae 375, maintained limit of detection until 72 h, whereas P. aeruginosa 1544 sustained a 1 log reduction. Combination therapy had no activity against the two isolates with amikacin MIC ≥ 2048 mg/L. CONCLUSIONS Inhaled amikacin monotherapy showed bactericidal activity against most isolates tested with amikacin MICs ≤ 256 mg/L. Adjunct inhaled amikacin plus meropenem sustained this activity for 72 h for the tested isolates with amikacin/meropenem MIC ≤ 64/32 mg/L.
Collapse
Affiliation(s)
- Wonhee So
- Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT, USA
| | - Jared L Crandon
- Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT, USA
| | - Yukihiro Hamada
- Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT, USA
| | - David P Nicolau
- Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT, USA Division of Infectious Diseases, Hartford Hospital, Hartford, CT, USA
| |
Collapse
|
11
|
A meta-analysis of in vitro antibiotic synergy against Acinetobacter baumannii. J Microbiol Methods 2015; 119:31-6. [PMID: 26415528 DOI: 10.1016/j.mimet.2015.09.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 09/23/2015] [Accepted: 09/24/2015] [Indexed: 11/20/2022]
Abstract
The aim of the work was to describe the different in vitro models for testing synergism of antibiotics and gather the results of antibiotic synergy against multidrug-resistant Acinetobacter baumannii (MDR-Ab). The different original articles were obtained from different web sites. In order to compare the results obtained by the different methods for synergy testing, the Pearson chi-square and the Fischer tests were used. Moreover, non-parametric chi-square test was used in order to compare the frequency distribution in each analysed manuscript. In the current meta-analysis 24 manuscripts, which encompassed 2016 tests of in vitro synergism of different antimicrobials against MDR-Ab, were revised. Checkerboard synergy testing was used in 11 studies, which encompasses 1086 tests (53.9%); time-kill assays were applied in 12 studies, which encompass 359 tests (17.8%); gradient diffusion methods were used in seven studies, encompassing 293 tests (14.5%). And, finally, time-kill plus checkerboard were applied in two studies, encompassing 278 tests (13.8%). By comparing these data, checkerboard and time-kill methods were significantly more used than gradient diffusion methods (p<0.005). Regarding synergy rates obtained on the basis of the applied method, checkerboard provided 227 tests (20.9%) with a synergistic effect; time-kill assays yielded 222 tests (61.8%) with a synergistic effect; gradient diffusion methods only provided 29 tests (9.9%) with a synergistic effect; and, finally, time-kill plus checkerboard yielded just 15 tests (5.4%) with a synergistic effect. When comparing these percentages, synergy rates reported by time-kill methods were significantly higher than that obtained by checkerboard and gradient diffusion methods (p<0.005). On the basis of the revised data, the combinations of a bactericidal antibiotic plus Tigecycline, Vancomycin or Teicoplanin are not recommended. The best combinations of antibiotics are those which include bactericidal antibiotics such as Carbapenems, Fosfomycin, Amikacin, Polymyxins, Rifampicin and Ampicillin/Sulbactam.
Collapse
|
12
|
Ni W, Shao X, Di X, Cui J, Wang R, Liu Y. In vitro synergy of polymyxins with other antibiotics for Acinetobacter baumannii: a systematic review and meta-analysis. Int J Antimicrob Agents 2014; 45:8-18. [PMID: 25465524 DOI: 10.1016/j.ijantimicag.2014.10.002] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 10/01/2014] [Indexed: 01/27/2023]
Abstract
In order to provide preliminary guidance for rational antibiotic combination therapy in the clinic, a systematic review and meta-analysis was performed to evaluate the in vitro synergistic activity of polymyxins combined with other antibiotics against Acinetobacter baumannii. An extensive literature search was undertaken without restriction according to region, publication type or language. All available in vitro synergy tests on antibiotic combinations consisting of polymyxins were included. The primary outcome assessed was the in vitro activity of combination therapy on bacterial kill or inhibition. In total, 70 published studies and 31 conference proceedings reporting testing of polymyxins in combination with 11 classes consisting of 28 antibiotic types against 1484 A. baumannii strains were included in the analysis. In time-kill studies, high in vitro synergy and bactericidal activity were found for polymyxins combined with several antibiotic classes such as carbapenems and glycopeptides. Carbapenems or rifampicin combination could efficiently suppress the development of colistin resistance and displayed a >50% synergy rate against colistin-resistant strains. Synergy rates of chequerboard microdilution and Etest methods in most antibiotic combinations were generally lower than those of time-kill assays. The benefits of these antibiotic combinations should be further demonstrated by well-designed clinical studies.
Collapse
Affiliation(s)
- Wentao Ni
- Department of Respiratory Diseases, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Xiaodi Shao
- Department of Clinical Pharmacology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Xiuzhen Di
- Department of Clinical Pharmacology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Junchang Cui
- Department of Respiratory Diseases, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Rui Wang
- Department of Clinical Pharmacology, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Youning Liu
- Department of Respiratory Diseases, Chinese People's Liberation Army General Hospital, Beijing 100853, China.
| |
Collapse
|
13
|
Antimicrobial activity of the imipenem/rifampicin combination against clinical isolates of Acinetobacter baumannii grown in planktonic and biofilm cultures. World J Microbiol Biotechnol 2014; 30:3015-25. [PMID: 25298216 DOI: 10.1007/s11274-014-1728-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 08/21/2014] [Indexed: 10/24/2022]
Abstract
To investigate the antimicrobial activity of imipenem and rifampicin alone and in combination against clinical isolates of Acinetobacter baumannii grown in planktonic and biofilm cultures. Minimum inhibitory concentrations were determined for each isolate grown in suspension and in biofilm using a microbroth dilution method. Chequerboard assays and the agar disk diffusion assay were used to determine synergistic, indifferent or antagonistic interactions between imipenem and rifampicin. We used the tissue culture plate method for A. baumannii biofilm formation to measure the percentage of biofilm inhibition and the amount of extracellular DNA after the treatment. To understand the synergistic mechanisms, we conducted hydroxyl radical formation assays. The results were verified by confocal laser scanning microscopy. Imipenem and rifampicin showed effective antimicrobial activity against suspensions and biofilm cultures of A. baumannii, respectively. Synergistic antimicrobial effects between imipenem and rifampicin were observed in 13 and 17 of the 20 clinical isolates when in suspension and in biofilms, respectively. Imipenem and rifampicin alone and in combination generated hydroxyl radicals, which are highly reactive oxygen forms and the major components of bactericidal agents. Furthermore, treatment with imipenem and rifampicin individually or in combination has obvious antibiofilm effects. The synergistic activity of imipenem and rifampicin against clinical isolates of A. baumannii (in suspension and in biofilms) was observed in vitro. Therefore, we conclude that imipenem combined with rifampicin has the potential to be used as a combinatorial therapy for the treatment of infectious diseases caused by A. baumannii.
Collapse
|
14
|
Freire MP, Pierrotti LC, Filho HHC, Ibrahim KY, Magri ASGK, Bonazzi PR, Hajar L, Diz MPE, Pereira J, Hoff PM, Abdala E. Infection with Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae in cancer patients. Eur J Clin Microbiol Infect Dis 2014; 34:277-86. [DOI: 10.1007/s10096-014-2233-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 08/15/2014] [Indexed: 10/24/2022]
|
15
|
Majewski P, Wieczorek P, Ojdana D, Sacha PT, Wieczorek A, Tryniszewska EA. In vitro activity of rifampicin alone and in combination with imipenem against multidrug-resistant Acinetobacter baumannii harboring the blaOXA-72 resistance gene. ACTA ACUST UNITED AC 2014; 46:260-4. [PMID: 24447252 DOI: 10.3109/00365548.2013.865141] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND The growing incidence of multidrug resistance (MDR) in bacteria is an emerging challenge in the treatment of infections. Acinetobacter baumannii is an opportunistic pathogen prone to exhibit MDR that contributes significantly to nosocomial infections, particularly in severely ill patients. Thus, we performed research on rifampicin activity against selected MDR OXA-72 carbapenemase-producing A. baumannii strains. Since it is widely accepted that rifampicin should not be used as monotherapy in order to avoid the rapid development of rifampicin resistance, we evaluated the efficacy of combination therapy with imipenem. METHODS Minimal inhibitory concentrations (MICs) of both rifampicin and imipenem were determined by use of the broth microdilution method. Evaluations of the interactions between rifampicin and imipenem were performed by analysis of the fractional inhibitory concentration index (∑FIC), determined using the checkerboard titration method. RESULTS All tested isolates showed full susceptibility to rifampicin. The checkerboard method revealed synergism in 5 isolates (29%) and an additive effect in another 5 isolates (29%); no difference was reported in the remaining 7 isolates (41%). Strains moderately resistant to imipenem (MIC ≤ 64 mg/l) tended to show synergy or additive interaction. CONCLUSIONS We conclude that in vitro synergism or an additive interaction between rifampicin and imipenem most likely occurs in A. baumannii strains showing moderate resistance to imipenem (MIC ≤ 64 mg/l). Moreover, utilizing this combination in the therapy of infections caused by strains exhibiting higher levels of resistance (MIC > 64 mg/l) is not recommended since in this setting imipenem could not prevent the development of rifampicin resistance.
Collapse
Affiliation(s)
- Piotr Majewski
- From the Department of Microbiological Diagnostics and Infectious Immunology, Medical University of Bialystok , Bialystok , Poland
| | | | | | | | | | | |
Collapse
|