1
|
Guo Y, Liu H, Yang M, Ding R, Gao Y, Niu X, Deng X, Wang J, Feng H, Qiu J. Novel metallo-β-lactamases inhibitors restore the susceptibility of carbapenems to New Delhi metallo-lactamase-1 (NDM-1)-harbouring bacteria. Br J Pharmacol 2024; 181:54-69. [PMID: 37539785 DOI: 10.1111/bph.16210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 06/24/2023] [Accepted: 07/20/2023] [Indexed: 08/05/2023] Open
Abstract
BACKGROUND AND PURPOSE The production of metallo-β-lactamases is a major mechanisms adopted by bacterial pathogens to resist carbapenems. Repurposing approved drugs to restore the efficacy of carbapenems represents an efficient and cost-effective approach to fight infections caused by carbapenem resistant pathogens. EXPERIMENTAL APPROACH The nitrocefin hydrolysis assay was employed to screen potential New Delhi metallo-lactamase-1 (NDM-1) inhibitors from a commercially available U.S. Food and Drug Administration (FDA) approved drug library. The mechanism of inhibition was clarified by metal restoration, inductively coupled plasma mass spectrometry (ICP-MS) and molecular dynamics simulation. The in vitro synergistic antibacterial effect of the identified inhibitors with meropenem was determined by the checkerboard minimum inhibitory concentration (MIC) assay, time-dependent killing assay and combined disc test. Three mouse infection models were used to further evaluate the in vivo therapeutic efficacy of combined therapy. KEY RESULTS Twelve FDA-approved compounds were initially screened to inhibit the ability of NDM-1 to hydrolyse nitrocefin. Among these compounds, dexrazoxane, embelin, candesartan cilexetil and nordihydroguaiaretic acid were demonstrated to inhibit all tested metallo-β-lactamases and showed an in vitro synergistic bactericidal effect with meropenem against metallo-β-lactamases-producing bacteria. Dexrazoxane, embelin and candesartan cilexetil are metal ion chelating agents, while the inhibition of NDM-1 by nordihydroguaiaretic acid involves its direct binding to the active region of NDM-1. Furthermore, these four drugs dramatically rescued the treatment efficacy of meropenem in three infection models. CONCLUSIONS AND IMPLICATIONS Our observations indicated that dexrazoxane, embelin, candesartan cilexetil and nordihydroguaiaretic acid are promising carbapenem adjuvants against metallo-β-lactamases-positive carbapenem resistant bacterial pathogens.
Collapse
Affiliation(s)
- Yan Guo
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Hongtao Liu
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Mengge Yang
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Rui Ding
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yawen Gao
- College of Food Science and Engineering, Jilin University, Changchun, Jilin, China
| | - Xiaodi Niu
- College of Food Science and Engineering, Jilin University, Changchun, Jilin, China
| | - Xuming Deng
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jianfeng Wang
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Haihua Feng
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Jiazhang Qiu
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| |
Collapse
|
2
|
Zhang S, Mi P, Wang J, Li P, Luo K, Liu S, Al-Shamiri MM, Lei J, Lai S, Han B, Chen Y, Han L, Han S. The optimized carbapenem inactivation method for objective and accurate detection of carbapenemase-producing Acinetobacter baumannii. Front Microbiol 2023; 14:1185450. [PMID: 37520356 PMCID: PMC10372451 DOI: 10.3389/fmicb.2023.1185450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 06/27/2023] [Indexed: 08/01/2023] Open
Abstract
The modified carbapenem inactivation method (mCIM) recommended by the Clinical and Laboratory Standards Institute is not applicable for detecting carbapenemases in Acinetobacter baumannii. Four currently reported phenotypic detection methods, namely, the modified Hodge test, the mCIM, the adjusted mCIM, and the simplified carbapenem inactivation method (sCIM), did not perform well in our 90 clinical A. baumannii isolates. Thus, the minimal inhibitory concentrations (MICs) of carbapenems and the existence and expression of carbapenemase-encoding genes were detected to explain the results. According to the E-test, which was more accurate than the VITEK 2 system, 80.0 and 41.1% were resistant to imipenem (IPM) and meropenem (MEM), respectively, and 14.4 and 53.3% exhibited intermediate resistance, respectively. Five β-lactamase genes were found, of which blaOXA-51-like, blaTEM, and blaOXA-23-like were detected more frequently in 85 non-susceptible strains. The expression of blaOXA-23-like was positively correlated with the MIC values of IPM and MEM. Therefore, an improved approach based on the mCIM, designated the optimized CIM (oCIM), was developed in this study to detect carbapenemases more accurately and reproducibly. The condition was improved by evaluating the factors of A. baumannii inoculum, incubation broth volume, and MEM disk incubation time. Obvious high sensitivity (92.94%) and specificity (100.00%) were obtained using the oCIM, which was cost-effective and reproducible in routine laboratory work.
Collapse
Affiliation(s)
- Sirui Zhang
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Peng Mi
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
- Department of Laboratory Medicine, Shaanxi Provincial People’s Hospital, Xi’an, China
| | - Jingdan Wang
- School of Public Health, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Pu Li
- School of Public Health, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Kai Luo
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Shuyan Liu
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Mona Mohamed Al-Shamiri
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Jin’e Lei
- Department of Laboratory Medicine, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Simin Lai
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Bei Han
- School of Public Health, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Yanjiong Chen
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Lei Han
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, China
| | - Shaoshan Han
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi'an, China
| |
Collapse
|
3
|
Phenotypic Carbapenemase Production and bla
OXA detecting by PCR in Acinetobacter baumannii isolates from a Hospital of Infectious Diseases from North-East Romania. REV ROMANA MED LAB 2022. [DOI: 10.2478/rrlm-2022-0033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Abstract
Introduction: In the last 40 years, Acinetobacter baumannii has been among the bacteria known to acquire multiple mechanisms of antibiotic resistance and, as a result, it is now one of the pathogens involved in healthcare-associated infections with multidrug resistant strains. Our study aimed to assess the production of carbapenemases in carbapenem-resistant A. baumannii by means of phenotypic methods and polymerase chain reaction technique (PCR), as well as to appraise the performances of carbapenemase detection by phenotypic tests compared to the PCR approach.
Materials and Methods: We used phenotypic methods (E-test MBL, CIM, MHT, Rosco® Kit/OXA/MBL, OXA-23 K-SeT® assay) to investigate the production of carbapenemases in 43 carbapenem-resistant A. baumannii isolates, and PCR to screen for the genes blaOXA-23, blaOXA-24, blaOXA-58, blaOXA-51, blaVIM, blaIMP and blaNDM.
Results: The carbapenem inactivation method (CIM) at 2 hours, CIM at 4h, OXA-23 K-SeT® assay, Rosco® Kit/OXA, and modified Hodge test (MHT) identified 26%, 63%, 65%, 81%, and 42% carbapenemase-producing isolates, respectively. The phenotypic E-test MBL detected metallo-β-lactamase (MBL) production in 79% of strains. PCR revealed blaOXA-51 in all the isolates, blaOXA-23 in 35/43 (81%), blaOXA-24 in 28/43 (65%), blaVIM in 7/43 (3%) and blaOXA-58, blaIMP, blaNDM were not detected.
Conclusion: Because phenotypic tests do not highlight all the carbapenemase-producing strains, their results must be interpreted with caution relative to their level of performance, and negative results should be confirmed by means of PCR.
Collapse
|
4
|
A Variant Carbapenem Inactivation Method (CIM) for Acinetobacter baumannii Group with Shortened Time-to-Result: rCIM-A. Pathogens 2022; 11:pathogens11040482. [PMID: 35456157 PMCID: PMC9024794 DOI: 10.3390/pathogens11040482] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/10/2022] [Accepted: 04/13/2022] [Indexed: 02/01/2023] Open
Abstract
Carbapenem-resistant Acinetobacter baumannii group organisms (CRAB) are challenging because the choice between targeted, new antibiotic drug options and hygiene measures should be guided by a timely identification of resistance mechanisms. In CRAB, acquired class-D carbapenemases (CHDLs) are active against meropenem and imipenem. If PCR methods are not the first choice, phenotypic methods have to be implemented. While promising, the carbapenemase inactivation method (CIM) using meropenem-hydrolysis is, however, hampered by poor performance or overly long time-to-result. We developed a rapid CIM (rCIM-A) with good performance using ertapenem, imipenem, and meropenem disks, 2-h permeabilization and incubation with the test strain in trypticase soy broth, and a read-out of residual carbapenem activity after 6 h, and optionally after 16–18 h. Using clinical isolates and type-strains of Acinetobacter (n = 67) not harboring carbapenemases (n = 28) or harboring acquired carbapenemases (n = 39), the sensitivity of detection was 97.4% with the imipenem disk after 6 h at a specificity of 92.9%. If the inhibition zone around the ertapenem disk at 6 h was 6 or ≤26 mm at 16–18 h, or ≤25.5 mm for meropenem, the specificity was 100%. Because of the high negative predictive value, the rCIM-A seems particularly appropriate in areas of lower CRAB-frequency.
Collapse
|
5
|
Carbapenemase-producing Enterobacterales infections: Recent advances in diagnosis and treatment. Int J Antimicrob Agents 2022; 59:106528. [DOI: 10.1016/j.ijantimicag.2022.106528] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 01/07/2022] [Accepted: 01/12/2022] [Indexed: 11/19/2022]
|
6
|
Mohamed A, Daef E, Nafie A, Shaban L, Ibrahim M. Characteristics of Carbapenem-Resistant Gram-Negative Bacilli in Patients with Ventilator-Associated Pneumonia. Antibiotics (Basel) 2021; 10:antibiotics10111325. [PMID: 34827263 PMCID: PMC8615042 DOI: 10.3390/antibiotics10111325] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 10/25/2021] [Accepted: 10/27/2021] [Indexed: 01/16/2023] Open
Abstract
Carbapenem-resistant Gram-negative bacilli (CR-GNB) has become a global threat. In hospital settings, the association of CR-GNB with ventilator-associated pneumonia (VAP) is a critical public health concern owing to their high resistance rate to most antibiotics. The present study aims to identify the frequency of carbapenem-resistance and to determine the rate of multidrug resistance (MDR), extensive drug resistance (XDR) and pan-drug resistance (PDR) among CR-GNB infections in VAP. Antimicrobial susceptibility testing was carried out using the disk diffusion method and the detection of carbapenemases was screened using the imipenem-E test and the modified carbapenem-inactivation method (mCIM). The isolates were verified by polymerase chain reaction (PCR) for the presence of blaNDM, blaSPM, blaVIM, blaIMP and blaGIM genes. 89.5%, 14%, 17.5%, 10.5%, 3.5% of isolates exhibited the presence of blaNDM, blaVIM, blaSPM, blaIMP and blaGIM, respectively. 76%, 17% and 7% of isolates were PDR, XDR, and MDR, respectively. Carbapenem-resistance genes were identified in a significant percentage and blaNDM was the most predominant gene. All isolates were highly resistant to most antibiotics. This health concern has proven to be a big challenge in developing countries such as Egypt, as it is associated with high morbidity, high mortality, and raised healthcare costs.
Collapse
Affiliation(s)
- Amira Mohamed
- Clinical Pharmacy, Women’s Health Hospital, Assiut University, Assiut 71711, Egypt;
| | - Enas Daef
- Microbiology and Immunology Department, Faculty of Medicine, Assiut University, Assiut 71711, Egypt; (E.D.); (A.N.)
| | - Amany Nafie
- Microbiology and Immunology Department, Faculty of Medicine, Assiut University, Assiut 71711, Egypt; (E.D.); (A.N.)
| | - Lamia Shaban
- Chest Department, Faculty of Medicine, Assiut University, Assiut 71711, Egypt;
| | - Maggie Ibrahim
- Microbiology and Immunology Department, Faculty of Medicine, Assiut University, Assiut 71711, Egypt; (E.D.); (A.N.)
- Correspondence:
| |
Collapse
|
7
|
Nockelmann L, Cremanns M, Gatermann SG, Pfennigwerth N. Evaluation of the rCIM for carbapenemase detection in Enterobacterales and Pseudomonas aeruginosa and description of the TSBrCIM, an optimized variant. J Microbiol Methods 2021; 190:106345. [PMID: 34662678 DOI: 10.1016/j.mimet.2021.106345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 09/24/2021] [Accepted: 09/24/2021] [Indexed: 10/20/2022]
Abstract
OBJECTIVES The rapid Carbapenem Inactivation Method (rCIM) was evaluated with a strain collection of 164 and 69 carbapenem-resistant Enterobacterales and Pseudomonas aeruginosa, respectively, that produced various carbapenemases. For an improved carbapenemase detection in Enterobacterales, an optimized variant of the rCIM named TSBrCIM was developed. METHODS Bacterial isolates were incubated with two meropenem disks in distilled water (rCIM) or tryptic soy broth (TSBrCIM). After centrifugation, the supernatant was incubated with a susceptible E. coli indicator strain in tryptic soy broth. Growth of the indicator strain implied carbapenemase activity in the test strain. RESULTS The rCIM detected 100/113 carbapenemase-producing Enterobacterales, resulting in a sensitivity of 88.5% and a specificity of 94.1%. For P. aeruginosa, sensitivity and specificity were 96.0% and 100%, respectively. The TSBrCIM was able to detect 105/113 carbapenemase-producing Enterobacterales, resulting in a sensitivity of 92.9% and a specificity of 96.1%. CONCLUSION This study shows that the TSBrCIM can be valuable tool for detection of carbapenemases in Enterobacterales in the clinical laboratory, while the rCIM showed the best results for carbapenemase detection in P. aeruginosa.
Collapse
Affiliation(s)
- Laura Nockelmann
- German National Reference Centre for Multidrug-resistant Gram-negative Bacteria, Department of Medical Microbiology, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Martina Cremanns
- German National Reference Centre for Multidrug-resistant Gram-negative Bacteria, Department of Medical Microbiology, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Sören G Gatermann
- German National Reference Centre for Multidrug-resistant Gram-negative Bacteria, Department of Medical Microbiology, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Niels Pfennigwerth
- German National Reference Centre for Multidrug-resistant Gram-negative Bacteria, Department of Medical Microbiology, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany.
| |
Collapse
|
8
|
Kuchibiro T, Komatsu M, Yamasaki K, Nakamura T, Nishio H, Kimura K, Niki M, Kida K, Ohama M, Fukuda N, Sawa K, Nakamura A, Nishi I. Comparison of the performance of three carbapenem inactivation methods for the detection of carbapenemase-producing gram-negative bacilli. J Infect Chemother 2021; 27:1634-1638. [PMID: 34376351 DOI: 10.1016/j.jiac.2021.07.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 07/22/2021] [Accepted: 07/28/2021] [Indexed: 12/14/2022]
Abstract
INTRODUCTION The carbapenem inactivation method test (CIM) was developed as a method for detecting carbapenemase-producing Gram-negative bacilli, and the modified CIM (mCIM) was recommended by the CLSI for as an improved method in M100-S27. However, few studies have evaluated the influence of bacterial species and genotype on its sensitivity and specificity. In this study, we evaluate the performance of these improved modified CIM methods with mCIM. METHODS As strains, clinical isolates from Naga Municipal Hospital and stored strains from the Study of Bacterial Resistance in the Kinki Region of Japan were used. The mCIM, CIM-Tris, and simple CIM (sCIM) test methods were applied to 120 Enterobacterales, 40 Pseudomonas aeruginosa, and 37 Acinetobacter spp. The procedure and criteria for each method were based on the original papers and the CLSI M - 100 S27 documents. RESULTS The sensitivity of the test methods in the detection of carbapenemase in Enterobacterales, Pseudomonas spp., and Acinetobacter spp. was as follows: mCIM, 98.9%, 90.0%, and 76.5%, respectively; CIM-Tris, 94.4%, 100%, 100%; and sCIM 98.9%, 85.0%, 76.5%. All methods showed 100% specificity in Enterobacterales, Pseudomonas spp., and Acinetobacter spp. Each method performed well in the detection of metallo β-lactamase-producing strains, however, the sensitivity tended to be low in the detection of the organisms producing serine-type carbapenemase, such as GES, OXA-23, and OXA-51. CONCLUSIONS Care must be taken when selecting test methods because the sensitivity of the detection differs depending on the bacterial species and genotype.
Collapse
Affiliation(s)
- Tomokazu Kuchibiro
- Department of Clinical Laboratory, Naga Municipal Hospital, Wakayama, Japan.
| | - Masaru Komatsu
- Department of Clinical Laboratory Science, Tenri Health Care University, Nara, Japan
| | - Katsutoshi Yamasaki
- Department of Medical Life Science, Kurashiki University of Science and the Arts, Okayama, Japan
| | - Tatsuya Nakamura
- Department of Medical Technology and Sciences Facility of Health Sciences, Kyoto Tachibana University, Kyoto, Japan
| | - Hisaaki Nishio
- Department of Clinical Laboratory, Shiga Medical Center for Children, Shiga, Japan
| | - Keigo Kimura
- Laboratory for Clinical Investigation, Osaka University Hospital, Osaka, Japan
| | - Makoto Niki
- Department of Infection Control and Prevention, Osaka City University Hospital, Osaka, Japan
| | - Kaneyuki Kida
- Clinical Laboratory, Japanese Red Cross Otsu Hospital, Shiga, Japan
| | - Masanobu Ohama
- Clinical Laboratory, Japanese Red Cross Otsu Hospital, Shiga, Japan
| | - Nozomi Fukuda
- Department of Clinical Laboratory, Osaka Police Hospital, Osaka, Japan
| | - Kana Sawa
- Department of Clinical Laboratory, Osaka Police Hospital, Osaka, Japan
| | - Akihiro Nakamura
- Department of Clinical Laboratory Science, Tenri Health Care University, Nara, Japan
| | - Isao Nishi
- Laboratory for Clinical Investigation, Osaka University Hospital, Osaka, Japan
| |
Collapse
|
9
|
Berneking L, Both A, Berinson B, Hoffmann A, Lütgehetmann M, Aepfelbacher M, Rohde H. Performance of the BD Phoenix CPO detect assay for detection and classification of carbapenemase-producing organisms. Eur J Clin Microbiol Infect Dis 2020; 40:979-985. [PMID: 33245470 PMCID: PMC8084821 DOI: 10.1007/s10096-020-04094-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 10/28/2020] [Indexed: 02/08/2023]
Abstract
Increasing worldwide, prevalence of carbapenem-resistant gram-negative bacteria demands urgent a need for rapid detection and accurate identification of carbapenemases. The BD Phoenix CPO detect (PCD) assay possesses an in-built capacity for parallel susceptibility testing and detection of carbapenemases. Here, the ability of the assay to detect and classify carbapenemase production was tested in a collection of carbapenem-resistant Enterobacterales and non-fermentative gram-negative rods. The ability of the PCD assay to detect and classify carbapenemases was investigated in a collection of 194 clinical, carbapenem-resistant isolates (Enterobacterales [n = 65]; non-fermentative gram-negative rods [n = 129]). AST results were compared to MICS determined by gradient diffusion to determine accuracy of the PCD assay. The accuracy of the PCD assay to detect carbapenemases was compared to the results of molecular isolate characterization using a LDT multiplex carbapenemase PCR assay. All 194 isolates classified as carbapenem-resistant by reference susceptibility testing were also classified correctly as CRO by the PCD assay. Performance analysis of the PCD assay to detect carbapenemase production revealed an overall sensitivity of 98.29% and specificity of 17.95% for the detection of carbapenemase production. For the classification of carbapenemases classes A, B, and D, the PCD correctly classified 79.17% Enterobacterales and 67.16% non-fermentative gram-negative rods. The PCD assay is a reliable tool for the detection of carbapenem resistance and allows for parallel analysis of carbapenemase production. However, while sensitivity is high, low specificity in carbapenemase detection and erroneous classification demands mandatory confirmation by alternative methods, especially in non-fermentative gram-negative bacteria.
Collapse
Affiliation(s)
- Laura Berneking
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany
| | - Anna Both
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany
| | - Benjamin Berinson
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany
| | - Armin Hoffmann
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany
| | - Marc Lütgehetmann
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany
| | - Martin Aepfelbacher
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany
| | - Holger Rohde
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universitätsklinikum Hamburg-Eppendorf, Martinistraße 52, D-20246, Hamburg, Germany.
| |
Collapse
|