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Bello-López E, Escobedo-Muñoz AS, Guerrero G, Cruz-Córdova A, Garza-González E, Hernández-Castro R, Zarain PL, Morfín-Otero R, Volkow P, Xicohtencatl-Cortes J, Cevallos MA. Acinetobacter pittii: the emergence of a hospital-acquired pathogen analyzed from the genomic perspective. Front Microbiol 2024; 15:1412775. [PMID: 38989032 PMCID: PMC11233732 DOI: 10.3389/fmicb.2024.1412775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 05/22/2024] [Indexed: 07/12/2024] Open
Abstract
Acinetobacter pittii has increasingly been associated with several types of hospital-acquired severe infections. Genes implicated in carbapenem resistance, tigecycline resistance, or genes encoding extended spectrum cephalosporinases, such as blaADC, are commonly found in isolates implicated in these infections. A. pittii strains that are pandrug resistant have occasionally been identified. Food for human consumption, animals and plants are environmental sources of this pathogen. An alarming situation is that A. pitti has been identified as responsible for outbreaks in different regions worldwide. In this study, 384 genomes of A. pittii were analyzed, comprising sequences from clinical and non-clinical origins from 32 countries. The objective was to investigate if clinical strains possess genetic traits facilitating hospital adaptation. Results indicate significant genomic variability in terms of size and gene content among A. pittii isolates. The core genome represents a small portion (25-36%) of each isolate's genome, while genes associated with antibiotic resistance and virulence predominantly belong to the accessory genome. Notably, antibiotic resistance genes are encoded by a diverse array of plasmids. As the core genome between environmental and hospital isolates is the same, we can assume that hospital isolates acquired ARGs due to a high selective pressure in these settings. The strain's phylogeographic distribution indicates that there is no geographical bias in the isolate distribution; isolates from different geographic regions are dispersed throughout a core genome phylogenetic tree. A single clade may include isolates from extremely distant geographical areas. Furthermore, strains isolated from the environment or animal, or plant sources frequently share the same clade as hospital isolates. Our analysis showed that the clinical isolates do not already possess specific genes, other than antibiotic-resistant genes, to thrive in the hospital setting.
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Affiliation(s)
- Elena Bello-López
- Universidad Nacional Autónoma de México, Centro de Ciencias Genómicas, Programa de Genómica Evolutiva, Cuernavaca, Mexico
| | - Ana Sofía Escobedo-Muñoz
- Universidad Nacional Autónoma de México, Centro de Ciencias Genómicas, Programa de Genómica Evolutiva, Cuernavaca, Mexico
| | - Gabriela Guerrero
- Universidad Nacional Autónoma de México, Centro de Ciencias Genómicas, Unidad de Análisis Bioinformáticos, Cuernavaca, Mexico
| | - Ariadnna Cruz-Córdova
- Unidad de Enfermedades Infecciosas, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico
| | - Elvira Garza-González
- Universidad Autónoma de Nuevo León, Facultad de Medicina/Hospital Universitario Dr. José Eleuterio González, Departamento de Bioquímica y Medicina Molecular, Monterrey, Mexico
| | - Rigoberto Hernández-Castro
- Departamento de Ecología de Agentes Patógenos, Hospital General Dr. Manuel Gea González, Ciudad de México, Mexico
| | - Patricia Lozano Zarain
- Benemérita Universidad Autónoma de Puebla, Instituto de Ciencias, Centro de Investigaciones en Ciencias Microbiológicas, Laboratorio de Microbiología Hospitalaria y de la Comunidad, Puebla, Mexico
| | - Rayo Morfín-Otero
- Instituto de Patología Infecciosa y Experimental, Universidad de Guadalajara, Guadalajara, Mexico
| | - Patricia Volkow
- Instituto Nacional de Cancerología, Departamento de Enfermedades Infecciosas, Ciudad de México, Mexico
| | - Juan Xicohtencatl-Cortes
- Unidad de Enfermedades Infecciosas, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez, Ciudad de México, Mexico
| | - Miguel A Cevallos
- Universidad Nacional Autónoma de México, Centro de Ciencias Genómicas, Programa de Genómica Evolutiva, Cuernavaca, Mexico
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Mendes SG, Combo SI, Allain T, Domingues S, Buret AG, Da Silva GJ. Co-regulation of biofilm formation and antimicrobial resistance in Acinetobacter baumannii: from mechanisms to therapeutic strategies. Eur J Clin Microbiol Infect Dis 2023; 42:1405-1423. [PMID: 37897520 PMCID: PMC10651561 DOI: 10.1007/s10096-023-04677-8] [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: 08/23/2023] [Accepted: 10/02/2023] [Indexed: 10/30/2023]
Abstract
In recent years, multidrug-resistant Acinetobacter baumannii has emerged globally as a major threat to the healthcare system. It is now listed by the World Health Organization as a priority one for the need of new therapeutic agents. A. baumannii has the capacity to develop robust biofilms on biotic and abiotic surfaces. Biofilm development allows these bacteria to resist various environmental stressors, including antibiotics and lack of nutrients or water, which in turn allows the persistence of A. baumannii in the hospital environment and further outbreaks. Investigation into therapeutic alternatives that will act on both biofilm formation and antimicrobial resistance (AMR) is sorely needed. The aim of the present review is to critically discuss the various mechanisms by which AMR and biofilm formation may be co-regulated in A. baumannii in an attempt to shed light on paths towards novel therapeutic opportunities. After discussing the clinical importance of A. baumannii, this critical review highlights biofilm-formation genes that may be associated with the co-regulation of AMR. Particularly worthy of consideration are genes regulating the quorum sensing system AbaI/AbaR, AbOmpA (OmpA protein), Bap (biofilm-associated protein), the two-component regulatory system BfmRS, the PER-1 β-lactamase, EpsA, and PTK. Finally, this review discusses ongoing experimental therapeutic strategies to fight A. baumannii infections, namely vaccine development, quorum sensing interference, nanoparticles, metal ions, natural products, antimicrobial peptides, and phage therapy. A better understanding of the mechanisms that co-regulate biofilm formation and AMR will help identify new therapeutic targets, as combined approaches may confer synergistic benefits for effective and safer treatments.
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Affiliation(s)
- Sérgio G Mendes
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada
- Faculty of Pharmacy, University of Coimbra, 3000-548, Coimbra, Portugal
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3000-548, Coimbra, Portugal
| | - Sofia I Combo
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada
- Faculty of Pharmacy, University of Coimbra, 3000-548, Coimbra, Portugal
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3000-548, Coimbra, Portugal
| | - Thibault Allain
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada
| | - Sara Domingues
- Faculty of Pharmacy, University of Coimbra, 3000-548, Coimbra, Portugal
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3000-548, Coimbra, Portugal
| | - Andre G Buret
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada
| | - Gabriela J Da Silva
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada.
- Faculty of Pharmacy, University of Coimbra, 3000-548, Coimbra, Portugal.
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3000-548, Coimbra, Portugal.
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Itani R, Khojah HMJ, Karout S, Rahme D, Hammoud L, Awad R, Abu-Farha R, Mukattash TL, Raychouni H, El-Lakany A. Acinetobacter baumannii: assessing susceptibility patterns, management practices, and mortality predictors in a tertiary teaching hospital in Lebanon. Antimicrob Resist Infect Control 2023; 12:136. [PMID: 38031181 PMCID: PMC10685635 DOI: 10.1186/s13756-023-01343-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 11/22/2023] [Indexed: 12/01/2023] Open
Abstract
BACKGROUND Acinetobacter baumannii is a major nosocomial pathogen capable of causing life-threatening infections. This bacterium is highly resistant to antibiotics and associated with high mortality rates. Therefore, this study aimed to evaluate A. baumannii's susceptibility patterns to antimicrobials, assess the appropriateness of the initiated antimicrobial therapy, determine the mortality rate, and identify predictors associated with mortality. METHODS A retrospective observational study was conducted among patients infected with A. baumannii at a university hospital in Lebanon through the revision of medical records. Kaplan-Meier survival analysis and log-rank tests were used to analyze time-to-mortality. Binary logistic regression was performed to identify predictors of mortality. RESULTS The records of 188 patients were screened, and 111 patients with A. baumannii infection were enrolled. Almost all isolates were resistant to carbapenem, and 43% of the isolates were extensively-drug resistant. Almost half of the patients received initial inappropriate antimicrobial therapy (n = 50, 45.1%). The 30-day mortality rate associated with A. baumannii infection was 71.2% (79/111). The time to mortality in patients who received inappropriate antimicrobial therapy (5.70 ± 1.07 days) was significantly shorter than in those who received appropriate antimicrobial therapy (12.43 ± 1.01 days, P < 0.01). Binary logistic regression revealed that inappropriate antimicrobial therapy (adjusted odds ratio [AOR] = 16.22, 95% CI 2.68-9.97, P = 0.002), mechanical ventilation (AOR = 14.72, 95% CI 3.27-6.61, P < 0.001), and thrombocytopenia (AOR = 8.82, 95% CI 1.12-9.75, P = 0.003) were more likely associated with mortality. CONCLUSIONS A. baumannii exhibits an alarming mortality rate among infected patients. Thrombocytopenia, mechanical ventilation, and inappropriate antibiotic administration are associated with mortality in patients infected with A. baumannii. The prompt initiation of appropriate antimicrobial therapy, infection control measures, and effective stewardship program are crucial to reduce the incidence of A. baumannii and improve the treatment outcomes.
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Affiliation(s)
- Rania Itani
- Pharmacy Practice Department, Faculty of Pharmacy, Beirut Arab University, Riad El Solh, 1107 2809, P.O. Box: 11-5020, Beirut, Lebanon
| | - Hani M J Khojah
- Department of Pharmacy Practice, College of Pharmacy, Taibah University, P.O. Box: 30051, 41477, Madinah, Kingdom of Saudi Arabia
| | - Samar Karout
- Pharmacy Practice Department, Faculty of Pharmacy, Beirut Arab University, Riad El Solh, 1107 2809, P.O. Box: 11-5020, Beirut, Lebanon.
| | - Deema Rahme
- Pharmacy Practice Department, Faculty of Pharmacy, Beirut Arab University, Riad El Solh, 1107 2809, P.O. Box: 11-5020, Beirut, Lebanon
- INSPECT-LB (Institut National de Santé Publique, d'Épidémiologie Clinique et de Toxicologie-Liban), Beirut, Lebanon
| | - Lara Hammoud
- Pharmacy Department, Hammoud Hospital University Medical Center, Sidon, Lebanon
| | - Reem Awad
- Pharmacy Practice Department, Faculty of Pharmacy, Beirut Arab University, Riad El Solh, 1107 2809, P.O. Box: 11-5020, Beirut, Lebanon
| | - Rana Abu-Farha
- Department of Clinical Pharmacy and Therapeutics, Faculty of Pharmacy, Applied Science Private University, P.O. Box: 11931, Amman, Jordan
| | - Tareq L Mukattash
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, P.O. Box: 3030, Irbid, 22110, Jordan
| | - Hamza Raychouni
- Intensive Care Unit, Central Military Hospital, Military Healthcare, Lebanese Army, Beirut, Lebanon
- Intensive Care Unit, American University of Beirut Medical Center, Beirut, Lebanon
| | - Abdalla El-Lakany
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Beirut Arab University, Riad El Solh, 1107 2809, P.O. Box: 11-5020, Beirut, Lebanon
- Department of Pharmacognosy, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
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Jha RK, Singh E, Khan RJ, Kumar A, Jain M, Muthukumaran J, Singh AK. Droperidol as a potential inhibitor of acyl-homoserine lactone synthase from A. baumannii: insights from virtual screening, MD simulations and MM/PBSA calculations. Mol Divers 2023; 27:1979-1999. [PMID: 36190592 DOI: 10.1007/s11030-022-10533-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 09/18/2022] [Indexed: 10/10/2022]
Abstract
Acinetobacter baumannii belongs to the ESKAPE family of pathogens and is a multi-drug resistant, gram-negative bacteria which follows the anaerobic form of respiration. A. baumannii is known to be the causative agent of hospital-related infections such as pneumonia, meningitis, endocarditis, septicaemia and a plethora of infections such as urinary tract infections found primarily in immunocompromised patients. These attributes of A. baumannii make it a priority pathogen against which potential therapeutic agents need to be developed. A. baumannii employs the formation of a biofilm to insulate its colonies from the outer environment, which allows it to grow under harsh environmental conditions and develop resistance against various drug molecules. Acyl-homoserine lactone synthase (AHLS) is an enzyme involved in the quorum-sensing pathway in A. baumannii, which is responsible for the synthesis of signal molecules known as acyl-homoserine lactones, which trigger the signalling pathway to regulate the factors involved in biofilm formation and regulation. The present study utilised a homology-modelled structure of AHLS to virtually screen it against the ZINC in trial/FDA-approved drug molecule library to find a subset of potential lead candidates. These molecules were then filtered based on Lipinski's, toxicological and ADME properties, binding affinity, and interaction patterns to delineate lead molecules. Finally, three promising molecules were selected, and their estimated binding affinity values were corroborated using AutoDock 4.2. The identified molecules and a control molecule were subsequently subjected to MD simulations to mimic the physiological conditions of protein ligand-binding interaction under the influence of a GROMOS forcefield. The global and essential dynamics analyses and MM/PBSA based binding free energy computations suggested Droperidol and Cipargamin as potential inhibitors against the binding site of AHLS from A. baumannii. The binding free energy calculations based on the MM/PBSA method showed excellent results for Droperidol (- 50.02 ± 4.67 kcal/mol) and Cipargamin (- 42.29 ± 4.05 kcal/mol).
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Affiliation(s)
- Rajat Kumar Jha
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, U.P., P.C. 201310, India
| | - Ekampreet Singh
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, U.P., P.C. 201310, India
| | - Rameez Jabeer Khan
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, U.P., P.C. 201310, India
| | - Ankit Kumar
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, U.P., P.C. 201310, India
| | - Monika Jain
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, U.P., P.C. 201310, India
| | - Jayaraman Muthukumaran
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, U.P., P.C. 201310, India.
| | - Amit Kumar Singh
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, U.P., P.C. 201310, India.
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Fatmawati NND, Suwardana GNR, Dharmika IAGW, Tarini NMA, Sujaya IN, Suranadi IW. Early detection of a possible multidrug-resistant Acinetobacter baumannii outbreak in the local hospital setting by using random amplified polymorphism DNA-polymerase chain reaction (RAPD-PCR), oxacillinase gene profiles, and antibiograms. IRANIAN JOURNAL OF MICROBIOLOGY 2023; 15:642-653. [PMID: 37941878 PMCID: PMC10628083 DOI: 10.18502/ijm.v15i5.13870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Background and Objectives Detecting the source of a potential outbreak of multidrug resistant (MDR) Acinetobacter baumannii is necessary to be investigated. This study aimed to detect the possibility of A. baumannii outbreak in a hospital setting using a combination of random amplified polymorphism DNA-polymerase chain reaction (RAPD-PCR), antibiograms, and the presence of oxacillinase genes. Materials and Methods The antibiogram of 31 clinical isolates and six environmental isolates of A. baumannii were determined by Vitek® 2 Compact. Oxacillinase genes (OXA-23, -24, -51, and -58) were detected by PCR, and RAPD-PCR was conducted using DAF-4 and ERIC-2 primers. The Similarity Index and dendrogram were generated using GelJ v2.3 software. Results The antibiograms showed that all MDR A. baumannii isolates has very limited susceptibility to cephalosporins, but mostly susceptible to tigecycline. All isolates were positive for bla OXA-51-like gene, thirty-two of 37 total isolates (86.5%) were positive for bla OXA-23-like gene, and none were positive for bla OXA-24-like and bla OXA-58-like genes. RAPD-PCR showed that the DAF-4 primer on average had more band visualization and lower Similarity Index's variation compared to the ERIC-2. The discriminatory power of DAF-4 was 0.906. There was a significant correlation between the DAF-4 dendrogram pattern with the antibiogram (r=0.494, p<0.001) and the presence of bla OXA-23-like gene (r=0.634, p<0.001) from all ICU A isolates. Six out of fourteen ICU A isolates belonged to the same cluster with >95% Similarity Index, while one clinical isolate having an identical dendrogram and antibiogram pattern with an environmental isolate within this cluster. Conclusion There is a high probability of MDR A. baumannii outbreak within ICU A detected by multiple analysis of RAPD-PCR, antibiogram and the bla OXA-23-like gene profiles. This combinatorial approach is conceivable to mitigate possible outbreak situations of A. baumannii in the local hospital without sophisticated microbiology laboratory.
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Affiliation(s)
- Ni Nengah Dwi Fatmawati
- Department of Clinical Microbiology, Faculty of Medicine, Udayana University, Bali, Indonesia
| | | | | | - Ni Made Adi Tarini
- Department of Clinical Microbiology, Faculty of Medicine, Udayana University, Bali, Indonesia
| | - I Nengah Sujaya
- Department of Public Health and Preventive Medicine, Faculty of Medicine, Udayana University, Bali, Indonesia
| | - I Wayan Suranadi
- Department of Anaesthesiology and Intensive Care, Faculty of Medicine, Udayana University, Bali, Indonesia
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Upmanyu K, Rizwanul Haq QM, Singh R. Antibacterial and Antibiofilm Properties of the Alexidine Dihydrochloride (MMV396785) against Acinetobacter baumannii. Antibiotics (Basel) 2023; 12:1155. [PMID: 37508252 PMCID: PMC10375957 DOI: 10.3390/antibiotics12071155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 05/25/2023] [Accepted: 05/26/2023] [Indexed: 07/30/2023] Open
Abstract
Antibiotic-resistant Acinetobacter baumannii infections among patients in hospital settings are rising at an alarming rate. The World Health Organization has designated carbapenem-resistant A. baumannii as a priority pathogen for drug discovery. Based on the open drug discovery approach, we screened 400 compounds provided as a Pandemic Response Box by MMV and DNDi to identify compounds with antibacterial and antibiofilm activity against two A. baumannii reference strains using a highly robust resazurin assay. In vitro screening identified thirty compounds with MIC ≤ 50μM having growth inhibitory properties against the planktonic state. Five compounds, with MMV IDs MMV396785, MMV1578568, MMV1578574, MMV1578564, and MMV1579850, were able to reduce metabolically active cells in the biofilm state. Of these five compounds, MMV396785 showed potential antibacterial and antibiofilm activity with MIC, MBIC, and MBEC of 3.125 μM, 12.5, and 25-100 µM against tested A. baumannii strains, respectively, showing biofilm formation inhibition by 93% and eradication of pre-formed biofilms by 60-77.4%. In addition, MMV396785 showed a drastic reduction in the surface area and thickness of biofilms. Further investigations at the molecular level by qRT-PCR revealed the downregulation of biofilm-associated genes when exposed to 50 µM MMV396785 in all tested strains. This study identified the novel compound MMV396785 as showing potential in vitro antibacterial and antibiofilm efficacy against A. baumannii.
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Affiliation(s)
- Kirti Upmanyu
- ICMR-National Institute of Pathology, Safdarjung Hospital Campus, New Delhi 110029, India
- Department of Biosciences, Jamia Millia Islamia, A Central University, New Delhi 110025, India
| | - Qazi Mohd Rizwanul Haq
- Department of Biosciences, Jamia Millia Islamia, A Central University, New Delhi 110025, India
| | - Ruchi Singh
- ICMR-National Institute of Pathology, Safdarjung Hospital Campus, New Delhi 110029, India
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7
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Cavallo I, Oliva A, Pages R, Sivori F, Truglio M, Fabrizio G, Pasqua M, Pimpinelli F, Di Domenico EG. Acinetobacter baumannii in the critically ill: complex infections get complicated. Front Microbiol 2023; 14:1196774. [PMID: 37425994 PMCID: PMC10325864 DOI: 10.3389/fmicb.2023.1196774] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 06/05/2023] [Indexed: 07/11/2023] Open
Abstract
Acinetobacter baumannii is increasingly associated with various epidemics, representing a serious concern due to the broad level of antimicrobial resistance and clinical manifestations. During the last decades, A. baumannii has emerged as a major pathogen in vulnerable and critically ill patients. Bacteremia, pneumonia, urinary tract, and skin and soft tissue infections are the most common presentations of A. baumannii, with attributable mortality rates approaching 35%. Carbapenems have been considered the first choice to treat A. baumannii infections. However, due to the widespread prevalence of carbapenem-resistant A. baumannii (CRAB), colistin represents the main therapeutic option, while the role of the new siderophore cephalosporin cefiderocol still needs to be ascertained. Furthermore, high clinical failure rates have been reported for colistin monotherapy when used to treat CRAB infections. Thus, the most effective antibiotic combination remains disputed. In addition to its ability to develop antibiotic resistance, A. baumannii is also known to form biofilm on medical devices, including central venous catheters or endotracheal tubes. Thus, the worrisome spread of biofilm-producing strains in multidrug-resistant populations of A. baumannii poses a significant treatment challenge. This review provides an updated account of antimicrobial resistance patterns and biofilm-mediated tolerance in A. baumannii infections with a special focus on fragile and critically ill patients.
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Affiliation(s)
- Ilaria Cavallo
- Microbiology and Virology, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| | - Alessandra Oliva
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
| | - Rebecca Pages
- Microbiology and Virology, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| | - Francesca Sivori
- Microbiology and Virology, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| | - Mauro Truglio
- Microbiology and Virology, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| | - Giorgia Fabrizio
- Microbiology and Virology, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| | - Martina Pasqua
- Department of Biology and Biotechnology "C. Darwin" Sapienza University of Rome, Rome, Italy
| | - Fulvia Pimpinelli
- Microbiology and Virology, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
| | - Enea Gino Di Domenico
- Department of Biology and Biotechnology "C. Darwin" Sapienza University of Rome, Rome, Italy
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8
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Roshini J, Patro LPP, Sundaresan S, Rathinavelan T. Structural diversity among Acinetobacter baumannii K-antigens and its implication in the in silico serotyping. Front Microbiol 2023; 14:1191542. [PMID: 37415807 PMCID: PMC10320297 DOI: 10.3389/fmicb.2023.1191542] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/30/2023] [Indexed: 07/08/2023] Open
Abstract
Acinetobacter baumannii is an emerging opportunistic pathogen. It exhibits multi-, extreme-, and pan-drug resistance against several classes of antibiotics. Capsular polysaccharide (CPS or K-antigen) is one of the major virulence factors which aids A. baumannii in evading the host immune system. K-antigens of A. baumannii exploit the Wzx/Wzy-dependent pathway that involves 13 different proteins for its assembly and transport onto the outer membrane. A total of 64 (out of 237 K-locus(KL) types) known K-antigen sugar repeating structures are discussed here and are classified into seven groups based on their initial sugars, QuiNAc4NAc, GalNAc, GlcNAc, Gal, QuiNAc/FucNAc, FucNAc, and GlcNAc along with Leg5Ac7Ac/Leg5Ac7R. Thus, the corresponding seven initializing glycosyltransferases (ItrA1, ItrA2, ItrA3, ItrA4, ItrB1, ItrB3, and ItrA3 along with ItrB2) exhibit serotype specificity. The modeled 3D-structural repository of the 64 K-antigens can be accessed at https://project.iith.ac.in/ABSD/k_antigen.html. The topology of K-antigens further reveals the presence of 2-6 and 0-4 sugar monomers in the main and side chains, respectively. The presence of negatively (predominant) or neutrally charged K-antigens is observed in A. baumannii. Such diversity in the K-antigen sugar composition provides the K-typing specificity (viz., 18-69% in terms of reliability) for Wza, Wzb, Wzc, Wzx, and Wzy proteins involved in the Wzx/Wzy-dependent pathway. Interestingly, the degree of uniqueness of these proteins among different K-types is estimated to be 76.79%, considering the 237 reference sequences. This article summarizes the A. baumannii K-antigen structural diversity and creation of a K-antigen digital repository and provides a systematic analysis of the K-antigen assembly and transportation marker proteins.
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Danielsen AS, Franconeri L, Page S, Myhre AE, Tornes RA, Kacelnik O, Bjørnholt JV. Clinical outcomes of antimicrobial resistance in cancer patients: a systematic review of multivariable models. BMC Infect Dis 2023; 23:247. [PMID: 37072711 PMCID: PMC10114324 DOI: 10.1186/s12879-023-08182-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 03/17/2023] [Indexed: 04/20/2023] Open
Abstract
BACKGROUND Infections are major causes of disease in cancer patients and pose a major obstacle to the success of cancer care. The global rise of antimicrobial resistance threatens to make these obstacles even greater and hinder continuing progress in cancer care. To prevent and handle such infections, better models of clinical outcomes building on current knowledge are needed. This internally funded systematic review (PROSPERO registration: CRD42021282769) aimed to review multivariable models of resistant infections/colonisations and corresponding mortality, what risk factors have been investigated, and with what methodological approaches. METHODS We employed two broad searches of antimicrobial resistance in cancer patients, using terms associated with antimicrobial resistance, in MEDLINE and Embase through Ovid, in addition to Cinahl through EBSCOhost and Web of Science Core Collection. Primary, observational studies in English from January 2015 to November 2021 on human cancer patients that explicitly modelled infection/colonisation or mortality associated with antimicrobial resistance in a multivariable model were included. We extracted data on the study populations and their malignancies, risk factors, microbial aetiology, and methods for variable selection, and assessed the risk of bias using the NHLBI Study Quality Assessment Tools. RESULTS Two searches yielded a total of 27,151 unique records, of which 144 studies were included after screening and reading. Of the outcomes studied, mortality was the most common (68/144, 47%). Forty-five per cent (65/144) of the studies focused on haemato-oncological patients, and 27% (39/144) studied several bacteria or fungi. Studies included a median of 200 patients and 46 events. One-hundred-and-three (72%) studies used a p-value-based variable selection. Studies included a median of seven variables in the final (and largest) model, which yielded a median of 7 events per variable. An in-depth example of vancomycin-resistant enterococci was reported. CONCLUSIONS We found the current research to be heterogeneous in the approaches to studying this topic. Methodological choices resulting in very diverse models made it difficult or even impossible to draw statistical inferences and summarise what risk factors were of clinical relevance. The development and adherence to more standardised protocols that build on existing literature are urgent.
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Affiliation(s)
- Anders Skyrud Danielsen
- Department of Microbiology, Oslo University Hospital, Oslo, Norway.
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.
| | - Léa Franconeri
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Oslo, Norway
- ECDC Fellowship Programme, Field Epidemiology Path (EPIET), European Centre for Disease Prevention and Control, (ECDC), Stockholm, Sweden
| | - Samantha Page
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Oslo, Norway
| | | | - Ragnhild Agathe Tornes
- The Library for the Healthcare Administration, Norwegian Institute of Public Health, Oslo, Norway
| | - Oliver Kacelnik
- Department of Infection Control and Preparedness, Norwegian Institute of Public Health, Oslo, Norway
| | - Jørgen Vildershøj Bjørnholt
- Department of Microbiology, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
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10
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Colistin Resistance in Acinetobacter baumannii: Molecular Mechanisms and Epidemiology. Antibiotics (Basel) 2023; 12:antibiotics12030516. [PMID: 36978383 PMCID: PMC10044110 DOI: 10.3390/antibiotics12030516] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/17/2023] [Accepted: 03/02/2023] [Indexed: 03/08/2023] Open
Abstract
Acinetobacter baumannii is recognized as a clinically significant pathogen causing a wide spectrum of nosocomial infections. Colistin was considered a last-resort antibiotic for the treatment of infections caused by multidrug-resistant A. baumannii. Since the reintroduction of colistin, a number of mechanisms of colistin resistance in A. baumannii have been reported, including complete loss of LPS by inactivation of the biosynthetic pathway, modifications of target LPS driven by the addition of phosphoethanolamine (PEtN) moieties to lipid A mediated by the chromosomal pmrCAB operon and eptA gene-encoded enzymes or plasmid-encoded mcr genes and efflux of colistin from the cell. In addition to resistance to colistin, widespread heteroresistance is another feature of A. baumannii that leads to colistin treatment failure. This review aims to present a critical assessment of relevant published (>50 experimental papers) up-to-date knowledge on the molecular mechanisms of colistin resistance in A. baumannii with a detailed review of implicated mutations and the global distribution of colistin-resistant strains.
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11
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Li T, Wang Z, Guo J, de la Fuente-Nunez C, Wang J, Han B, Tao H, Liu J, Wang X. Bacterial resistance to antibacterial agents: Mechanisms, control strategies, and implications for global health. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 860:160461. [PMID: 36435256 DOI: 10.1016/j.scitotenv.2022.160461] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 11/19/2022] [Accepted: 11/20/2022] [Indexed: 06/16/2023]
Abstract
The spread of bacterial drug resistance has posed a severe threat to public health globally. Here, we cover bacterial resistance to current antibacterial drugs, including traditional herbal medicines, conventional antibiotics, and antimicrobial peptides. We summarize the influence of bacterial drug resistance on global health and its economic burden while highlighting the resistance mechanisms developed by bacteria. Based on the One Health concept, we propose 4A strategies to combat bacterial resistance, including prudent Application of antibacterial agents, Administration, Assays, and Alternatives to antibiotics. Finally, we identify several opportunities and unsolved questions warranting future exploration for combating bacterial resistance, such as predicting genetic bacterial resistance through the use of more effective techniques, surveying both genetic determinants of bacterial resistance and the transmission dynamics of antibiotic resistance genes (ARGs).
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Affiliation(s)
- Ting Li
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China; State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Biotechnology, No. 20, Dongda Street, Fengtai District, Beijing 100071, PR China
| | - Zhenlong Wang
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St Lucia, Queensland 4072, Australia.
| | - Cesar de la Fuente-Nunez
- Machine Biology Group, Departments of Psychiatry and Microbiology, Institute for Biomedical Informatics, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America; Departments of Bioengineering and Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States of America; Penn Institute for Computational Science, University of Pennsylvania, Philadelphia, PA, United States of America.
| | - Jinquan Wang
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Bing Han
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Hui Tao
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Jie Liu
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China
| | - Xiumin Wang
- Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, PR China.
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12
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Swain A, Pan A. Protein Therapeutic Target Candidates Against Acinetobacter baumannii, a Pathogen of Concern to Planetary Health: A Network-Based Integrative Omics Drug Discovery Approach. OMICS : A JOURNAL OF INTEGRATIVE BIOLOGY 2023; 27:62-74. [PMID: 36735546 DOI: 10.1089/omi.2022.0180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Acinetobacter baumannii, an opportunistic gram-negative pathogen responsible for several nosocomial infections, has developed resistance to various antibiotics. Proteins involved in the two-component system (TCS), virulence, and antibiotic resistance (AR), help this pathogen in regulating antibiotic susceptibility and virulence mechanisms. The present study reports a network-based integrative omics approach to drug discovery to identify key regulatory proteins as therapeutic candidates against A. baumannii. We collected data on the TCS, virulence, and AR proteins from various databases (P2CS, VFDB, ARDB, and PAIDB), which were subjected to network, host-pathogen, and gene expression data analysis. Network analysis identified 43 hubs, and 10 proteins were found to be interacting with human proteins associated with vital pathways. Of the 53 (43 + 10) pathogen proteins, 46 had no orthologs in the human host. Twelve proteins, namely, RpfC, Wzc, OmpR, EnvZ, BfmS, PilG, histidine kinase, ABC 3 transport family protein, outer membrane porin OprD family, CsuD, Pgm, and LpxA, were differentially expressed in the resistant strain. We propose these proteins as key regulators that warrant evaluation as therapeutic target candidates in the future. Furthermore, structure prediction of ABC 3 transport family protein was performed as a case study. The findings from this study are poised to facilitate and inform drug discovery and development against A. baumannii.
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Affiliation(s)
- Aishwarya Swain
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Archana Pan
- Department of Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
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13
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Maleki A, Kaviar VH, Koupaei M, Haddadi MH, Kalani BS, Valadbeigi H, Karamolahi S, Omidi N, Hashemian M, Sadeghifard N, Mohamadi J, Heidary M, Khoshnood S. Molecular typing and antibiotic resistance patterns among clinical isolates of Acinetobacter baumannii recovered from burn patients in Tehran, Iran. Front Microbiol 2022; 13:994303. [PMID: 36386699 PMCID: PMC9664937 DOI: 10.3389/fmicb.2022.994303] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/26/2022] [Indexed: 11/05/2022] Open
Abstract
Acinetobacter baumannii (A. baumannii) is now considered a highly resistant pathogen to various types of antibiotics. Therefore, tracking the source of its prevalence and continuous control is crucial. This study aimed to determine antibiotic resistance and perform various molecular typing methods on clinical isolates of A. baumannii isolated from hospitalized burn patients in Shahid Motahari Burn Hospital, Tehran, Iran. Hospital isolates were confirmed by phenotypic and molecular methods. Then the sensitivity to different antibiotics was determined using the minimum inhibitory concentration (MIC) method. In order to perform molecular typing, three-locus dual assay multiplex polymerase chain reaction (PCR), multiple-locus variable-number tandem repeat analysis (MLVA), and multilocus sequence typing (MLST) methods were used. Among the 60 isolates collected, the frequencies of multidrug-resistant (MDR) and extensively drug-resistant (XDR) isolates were 90 and 10%, respectively. The most effective antibiotics were colistin with 100% and tigecycline with 83.33% sensitivity. Isolates were 100% resistant to piperacillin/tazobactam and cephalosporins, and 68.3% were resistant to carbapenem. The results of multiplex PCR showed five groups that international clone I (IC I) and IC II were the most common. The MLVA method identified 34 MLVA types (MTs), 5 clusters, and 25 singletons. Multilocus sequence typing results for tigecycline-resistant isolates showed seven different sequence types (STs). Increasing antibiotic resistance in A. baumannii isolates requires careful management to control and prevent the occurrence of the pre-antibiotic era. The results of this study confirm that the population structure of A. baumannii isolates has a high diversity. More extensive studies are needed in Iran to better understand the epidemiology of A. baumannii.
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Affiliation(s)
- Abbas Maleki
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Vahab Hassan Kaviar
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Maryam Koupaei
- Department of Microbiology and Immunology, School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
| | | | - Behrooz Sadeghi Kalani
- Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Hassan Valadbeigi
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Somayeh Karamolahi
- Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Nazanin Omidi
- Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Marziyeh Hashemian
- Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Nourkhoda Sadeghifard
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Jasem Mohamadi
- Department of Pediatrics, School of Medicine, Imam Khomeini Hospital, Ilam University of Medical Sciences, Ilam, Iran
| | - Mohsen Heidary
- Department of Laboratory Sciences, School of Paramedical Sciences, Sabzevar University of Medical Sciences, Sabzevar, Iran
- Cellular and Molecular Research Center, Sabzevar University of Medical Sciences, Sabzevar, Iran
- *Correspondence: Saeed Khoshnood, ; Mohsen Heidary,
| | - Saeed Khoshnood
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
- *Correspondence: Saeed Khoshnood, ; Mohsen Heidary,
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14
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Ejaz H, Qamar MU, Junaid K, Younas S, Taj Z, Bukhari SNA, Abdalla AE, Abosalif KOA, Ahmad N, Saleem Z, Salem EHM. The Molecular Detection of Class B and Class D Carbapenemases in Clinical Strains of Acinetobacter calcoaceticus-baumannii Complex: The High Burden of Antibiotic Resistance and the Co-Existence of Carbapenemase Genes. Antibiotics (Basel) 2022; 11:antibiotics11091168. [PMID: 36139948 PMCID: PMC9494970 DOI: 10.3390/antibiotics11091168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/13/2022] [Accepted: 08/27/2022] [Indexed: 11/29/2022] Open
Abstract
The emergence of carbapenem-resistant Acinetobacter calcoaceticus-baumannii complex (CRACB) in clinical environments is a significant global concern. These critical pathogens have shown resistance to a broad spectrum of antibacterial drugs, including carbapenems, mostly due to the acquisition of various β-lactamase genes. Clinical samples (n = 1985) were collected aseptically from multiple sources and grown on blood and MacConkey agar. Isolates and antimicrobial susceptibility were confirmed with the VITEK-2 system. The modified Hodge test confirmed the CRACB phenotype, and specific PCR primers were used for the molecular identification of blaOXA and blaNDM genes. Of the 1985 samples, 1250 (62.9%) were culture-positive and 200 (43.9%) were CRACB isolates. Of these isolates, 35.4% were recovered from pus samples and 23.5% from tracheal secretions obtained from patients in intensive care units (49.3%) and medical wards (20.2%). An antibiogram indicated that 100% of the CRACB isolates were resistant to β-lactam antibiotics and β-lactam inhibitors, 86.5% to ciprofloxacin, and 83.5% to amikacin, while the most effective antibiotics were tigecycline and colistin. The CRACB isolates displayed resistance to eight different AWaRe classes of antibiotics. All isolates exhibited the blaOXA-51 gene, while blaOXA-23 was present in 94.5%, blaVIM in 37%, and blaNDM in 14% of the isolates. The blaOXA-51, blaOXA-23, and blaOXA-24 genes co-existed in 13 (6.5%) isolates. CRACB isolates with co-existing blaOXA-23, blaOXA-24, blaNDM, blaOXA-51 and blaVIM genes were highly prevalent in clinical samples from Pakistan. CRACB strains were highly critical pathogens and presented resistance to virtually all antibacterial drugs, except tigecycline and colistin.
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Affiliation(s)
- Hasan Ejaz
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka 72388, Saudi Arabia
- Correspondence: (H.E.); (M.U.Q.)
| | - Muhammad Usman Qamar
- Department of Microbiology, Faculty of Life Sciences, Government College University Faisalabad, Faisalabad 38000, Pakistan
- Correspondence: (H.E.); (M.U.Q.)
| | - Kashaf Junaid
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka 72388, Saudi Arabia
| | - Sonia Younas
- HKU-Pasteur Research Pole, School of Public Health, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Zeeshan Taj
- Department of Microbiology, Faculty of Life Sciences, Government College University Faisalabad, Faisalabad 38000, Pakistan
| | - Syed Nasir Abbas Bukhari
- Department of Pharmaceutical Chemistry, College of Pharmacy, Jouf University, Sakaka 72388, Saudi Arabia
| | - Abualgasim E. Abdalla
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka 72388, Saudi Arabia
| | - Khalid O. A. Abosalif
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka 72388, Saudi Arabia
| | - Naveed Ahmad
- Department of Pharmaceutics, College of Pharmacy, Jouf University, Sakaka 72388, Saudi Arabia
| | - Zikria Saleem
- Department of Pharmacy Practice, Faculty of Pharmacy, Bahauddin Zakariya University, Multan 60000, Pakistan
| | - Eman H. M. Salem
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Menoufia University, Shebin El-Koom 32511, Egypt
- Department of Microbiology, King AbdulAziz Specialist Hospital, Sakaka 72341, Saudi Arabia
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15
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Gu Y, Zhang W, Lei J, Zhang L, Hou X, Tao J, Wang H, Deng M, Zhou M, Weng R, Xu J. Molecular epidemiology and carbapenem resistance characteristics of Acinetobacter baumannii causing bloodstream infection from 2009 to 2018 in northwest China. Front Microbiol 2022; 13:983963. [PMID: 36071964 PMCID: PMC9441628 DOI: 10.3389/fmicb.2022.983963] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 07/26/2022] [Indexed: 01/10/2023] Open
Abstract
Bloodstream infection (BSI) caused by Acinetobacter baumannii poses a serious threat to health and is correlated with high mortality in patients with hospital-acquired infections, so the molecular epidemiology and antimicrobial resistance characteristics of this pathogen urgently need to be explored. A. baumannii isolates from BSI patients were collected in three tertiary hospitals in northwest China from 2009 to 2018. Antimicrobial susceptibility testing was used to determine the MICs of the A. baumannii isolates. Whole-genome sequencing based on the Illumina platform was performed for molecular epidemiological analyses and acquired resistance gene screening. The efflux pump phenotype was detected by examining the influence of an efflux pump inhibitor. The expression of efflux pump genes was evaluated by RT-PCR. In total, 47 A. baumannii isolates causing BSI were collected and they presented multidrug resistance, including resistance to carbapenems. Clone complex (CC) 92 was the most prevalent with 30 isolates, among which a cluster was observed in the phylogenetic tree based on the core genome multi-locus sequence type, indicating the dissemination of a dominant clone. BSI-related A. baumannii isolates normally harbour multiple resistance determinants, of which oxacillinase genes are most common. Except for the intrinsic blaOXA-51 family, there are some carbapenem-resistant determinants in these A. baumannii isolates, including blaOXA-23, which is encoded within the Tn2006, Tn2008 or Tn2009 transposon structures and blaOXA-72. The transfer of blaOXA-72 was suggested by XerC/D site-specific recombination. The AdeABC efflux pump system contributed to carbapenem resistance in A. baumannii isolates, as evidenced by the high expression of some of its encoding genes. Both the clone dissemination and carbapenem resistance mediated by oxacillinase or efflux pumps suggest an effective strategy for hospital infection control.
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Affiliation(s)
- Yihai Gu
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Department of Microbiology, 3201 hospital, School of Medicine, Xi'an Jiaotong University, Hanzhong, Shaanxi, China
| | - Wei Zhang
- Department of Microbiology, 3201 hospital, School of Medicine, Xi'an Jiaotong University, Hanzhong, Shaanxi, China
| | - Jine Lei
- Department of Clinical Laboratory, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Lixia Zhang
- Department of Clinical Laboratory, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi, China
| | - Xuan Hou
- Department of Microbiology, 3201 hospital, School of Medicine, Xi'an Jiaotong University, Hanzhong, Shaanxi, China
| | - Junqi Tao
- Department of Microbiology, 3201 hospital, School of Medicine, Xi'an Jiaotong University, Hanzhong, Shaanxi, China
| | - Hui Wang
- Department of Microbiology, 3201 hospital, School of Medicine, Xi'an Jiaotong University, Hanzhong, Shaanxi, China
| | - Minghui Deng
- Department of Microbiology, 3201 hospital, School of Medicine, Xi'an Jiaotong University, Hanzhong, Shaanxi, China
| | - Mengrong Zhou
- Department of Microbiology, 3201 hospital, School of Medicine, Xi'an Jiaotong University, Hanzhong, Shaanxi, China
| | - Rui Weng
- Department of Microbiology, 3201 hospital, School of Medicine, Xi'an Jiaotong University, Hanzhong, Shaanxi, China
| | - Jiru Xu
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi, China
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Bacterial Community and Genomic Analysis of Carbapenem-Resistant Acinetobacter baumannii Isolates from the Environment of a Health Care Facility in the Western Region of Saudi Arabia. Pharmaceuticals (Basel) 2022; 15:ph15050611. [PMID: 35631436 PMCID: PMC9145440 DOI: 10.3390/ph15050611] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 11/17/2022] Open
Abstract
The escalating transmission of hospital-acquired infections, especially those due to antimicrobial-resistant bacteria, is a major health challenge worldwide. In this study, a culturomic analysis of bacterial community in a tertiary care hospital in the western region of Saudi Arabia is performed using environmental samples. The genome sequencing of four Acinetobacter baumannii was performed on isolates recovered from an intensive care unit (ICU) environment and clinical samples. A total of 361 bacterial isolates from surface and air samples were identified by MALDI-TOF technique or 16S rRNA gene sequencing. The isolates were classified into 70 distinct species, including ESKAPE pathogens. Resistance in Gram-positive isolates was mainly found to be against benzylpenicillin, azithromycin, ampicillin, and trimethoprim/sulfamethoxazole. Carbapenem- and multidrug-resistant isolates of A. baumannii and Klebsiella pneumonia were found on the ICU surfaces. Genome sequencing revealed that the carbapenem-resistant A. baumannii isolate from ICU environment was linked with those of clinical origin. The isolate Ab133-HEnv was classified as a novel sequence type (ST2528) based on a new allele of Oxf_gdhB-286. Three beta-lactam-antibiotic-resistance genes, blaADC-25, blaOXA-23, and blaOXA-66, were found in most of the analyzed genomes. Collectively, the results of this study highlight the spread of antimicrobial-resistant nosocomial pathogens in a health care facility in Saudi Arabia.
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Acinetobacter Baumannii: More Ways to Die. Microbiol Res 2022; 261:127069. [DOI: 10.1016/j.micres.2022.127069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 05/06/2022] [Accepted: 05/09/2022] [Indexed: 11/17/2022]
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Ababneh Q, Abulaila S, Jaradat Z. Isolation of extensively drug resistant Acinetobacter baumannii from environmental surfaces inside intensive care units. Am J Infect Control 2022; 50:159-165. [PMID: 34520789 DOI: 10.1016/j.ajic.2021.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/01/2021] [Accepted: 09/02/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND Acinetobacter baumannii is a nosocomial pathogen that has emerged as a major threat in the health-care settings, particularly intensive care units (ICUs). The aim of this study was to investigate the prevalence of A. baumannii in the environment of intensive care and emergency units in 4 hospitals in Jordan. METHODS A total of 311 surface and 26 air samples were collected from 6 different ICUs and 2 emergency units. Examined high-touch surfaces included bed rails, sinks, food tables, trolley handles, ventilator inlets, blankets, sheets, door handles, light switches, bedside tables and drawers, curtains, normal saline stands and neonatal incubators. A. baumannii isolates were identified by CHROMagar and confirmed using 2 different PCR assays. All obtained isolates were characterized for their antibiotic resistance phenotypes, biofilm formation capacities and were typed by multi-locus sequence typing. RESULTS Of the 337 samples, 24 A. baumannii isolates were recovered, mostly from surfaces in the internal medicine ICUs. Among the 24 isolates, 10 isolates were classified as extensively-resistant (XDR), harbored the blaOXA-23 like gene and able to form biofilms with varying capacities. ST2 was the most frequent sequence type, with all ST2 isolates classified as XDRs. CONCLUSIONS Our results showed that high-touch surfaces of adult and pediatric ICUs were contaminated with XDR A. baumannii isolates. Therefore, the cleaning practices of the surfaces and equipment surrounding ICU patients should be optimized, and health-care workers should continuously wash their hands and change their gloves constantly to control the spread of this pathogen.
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Affiliation(s)
- Qutaiba Ababneh
- Department of Biotechnology and Genetic Engineering, Faculty of Science and Arts, Jordan University of Science and Technology, Irbid, Jordan.
| | - Sally Abulaila
- Department of Biotechnology and Genetic Engineering, Faculty of Science and Arts, Jordan University of Science and Technology, Irbid, Jordan
| | - Ziad Jaradat
- Department of Biotechnology and Genetic Engineering, Faculty of Science and Arts, Jordan University of Science and Technology, Irbid, Jordan
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Pogue JM, Zhou Y, Kanakamedala H, Cai B. Burden of illness in carbapenem-resistant Acinetobacter baumannii infections in US hospitals between 2014 and 2019. BMC Infect Dis 2022; 22:36. [PMID: 34991499 PMCID: PMC8740340 DOI: 10.1186/s12879-021-07024-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 12/30/2021] [Indexed: 11/10/2022] Open
Abstract
Background Carbapenem-resistant (CR) Acinetobacter baumannii is a concerning pathogen in the USA and worldwide. Methods To assess the comparative burden of CR vs carbapenem-susceptible (CS) A. baumannii, this retrospective cohort study analyzed data from adult patients in 250 US hospitals from the Premier HealthCare Database (2014–2019). The outcomes analyzed included hospital length of stay (LOS), intensive care unit (ICU) utilization, discharge status, in-hospital mortality, readmission rates and hospital charges. Logistic regression was used for univariate and multivariable assessment of the independent relationship between relevant covariates, with a focus on CR status, and in-hospital mortality. Results 2047 Patients with CR and 3476 patients with CS A. baumannii infections were included. CR A. baumannii was more commonly isolated in respiratory tract infections (CR 40.7% and CS 27.0%, P < 0.01), whereas CS A. baumannii was more frequently associated with bloodstream infections (CS 16.7% and CR 8.6%, P < 0.01). Patients with CR A. baumannii infections had higher in-hospital (CR 16.4% vs CS 10.0%; P < 0.01) and 30-day (CR 32.2% vs CS 21.6%; P < 0.01) mortality compared to those with CS infections. After adjusting for age, sex, admission source, infection site, comorbidities, and treatment with in vitro active antibiotics within 72 h, carbapenem resistance was independently associated with increased mortality (adjusted odds ratio 1.42 [95% confidence interval 1.15; 1.75], P < 0.01). CR infections were also associated with increases in hospital length of stay (CR 11 days vs CS 9 days; P < 0.01), rate of intensive care unit utilization (CR 62.3% vs CS 45.1%; P < 0.01), rate of readmission with A. baumannii infections (CR 17.8% vs CS 4.0%; P < 0.01) and hospital charges. Conclusions These data suggest that the burden of illness is significantly greater for patients with CR A. baumannii infections and are at higher risk of mortality compared with CS infections in US hospitals. Supplementary Information The online version contains supplementary material available at 10.1186/s12879-021-07024-4.
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Affiliation(s)
- Jason M Pogue
- College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| | - Yun Zhou
- Genesis Research Inc., Hoboken, NJ, USA
| | | | - Bin Cai
- Shionogi Inc., 300 Campus Drive, Suite 100, Florham Park, NJ, 07932, USA.
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20
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Upmanyu K, Haq QMR, Singh R. Factors mediating Acinetobacter baumannii biofilm formation: Opportunities for developing therapeutics. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 3:100131. [PMID: 35909621 PMCID: PMC9325880 DOI: 10.1016/j.crmicr.2022.100131] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A. baumannii rapidly acquires antimicrobial resistance and causes biofilm associated infections. Strategies to target intrinsic factors mediating A. baumannii biofilm formation offer therapeutic prospects. Antimicrobial polymers and coating medical devices with antibiofilm agents may prevent biofilm associated infections. Biofilm matrix or regulatory mechanisms such as quorum sensing are potential targets for treating chronic infections. Phage therapy, photodynamic therapy and nanoparticle therapy are novel promising approaches for treating biofilm associated infections.
Acinetobacter baumannii has notably become a superbug due to its mounting risk of infection and escalating rates of antimicrobial resistance, including colistin, the last-resort antibiotic. Its propensity to form biofilm on biotic and abiotic surfaces has contributed to the majority of nosocomial infections. Bacterial cells in biofilms are resistant to antibiotics and host immune response, and pose challenges in treatment. Therefore current scenario urgently requires the development of novel therapeutic strategies for successful treatment outcomes. This article provides a holistic understanding of sequential events and regulatory mechanisms directing A. baumannii biofilm formation. Understanding the key factors functioning and regulating the biofilm machinery of A. baumannii will provide us insight to develop novel approaches to combat A. baumannii infections. Further, the review article deliberates promising strategies for the prevention of biofilm formation on medically relevant substances and potential therapeutic strategies for the eradication of preformed biofilms which can help tackle biofilm-associated A. baumannii infections. Advances in emerging therapeutic opportunities such as phage therapy, nanoparticle therapy and photodynamic therapy are also discussed to comprehend the current scenario and future outlook for the development of successful treatment against biofilm-associated A. baumannii infections.
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21
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Chandra P, V R, M S, Cs S, Mk U. Multidrug-resistant Acinetobacter baumannii infections: looming threat in the Indian clinical setting. Expert Rev Anti Infect Ther 2021; 20:721-732. [PMID: 34878345 DOI: 10.1080/14787210.2022.2016393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
INTRODUCTION The recent increase in multidrug-resistant strains of A. baumannii has increased the incidences of ventilator-associated pneumoniae, catheter-associated urinary tract infections, and central line-associated blood stream infections, together increasing hospital stay, treatment cost, and mortality. Resistance genes blaOXA and blaNDM are dominant in India. Carbapenem-resistant A. baumannii (CRAB) International clone-2 (IC-2) are rising in India. High dependency on carbapenems and last-resort combination of tigecycline and polymyxins have aggravated outcomes. Despite nursing barriers, ward closure, environmental disinfections etc for detecting and controlling transmission, MDR isolates and CRAB nosocomial outbreaks continue. Treatment cost overruns by AMR adversely affect 80% of Indians without insurance cover. AREA COVERED This narrative review will cover epidemiology, resistance pattern, genetic diversity, device-related infection, cost, and mortality due to multidrug-resistant and CRAB in India. A comprehensive literature search in PubMed and Google Scholar using appropriate keywords at different time points yielded relevant articles. EXPERT OPINION It is challenging to enforce policies to control MDR A. baumannii in India. Government and hospitals should enforce stringent infection control measures, surveillance, and antimicrobial stewardship to prevent further spread and emergence of more virulent and resistant strains. Knowledge on antibiotic resistance mechanisms can help design novel antibiotics that can evade, resistance.
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Affiliation(s)
- Prashant Chandra
- Department of Pharmacy Practice, Centre for Pharmaceutical care, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Rajesh V
- Department of Pharmacy Practice, Centre for Pharmaceutical care, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, India.,Department of Pharmacy Practice, Nitte Gulabi Shetty Memorial Institute of Pharmaceutical Sciences, Nitte University, Mangaluru, India
| | - Surulivelrajan M
- Department of Pharmacy Practice, Centre for Pharmaceutical care, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, India
| | - Shastry Cs
- Department of Pharmacy Practice, Nitte Gulabi Shetty Memorial Institute of Pharmaceutical Sciences, Nitte University, Mangaluru, India
| | - Unnikrishnan Mk
- Department of Pharmacy Practice, Nitte Gulabi Shetty Memorial Institute of Pharmaceutical Sciences, Nitte University, Mangaluru, India
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22
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Nanayakkara AK, Boucher HW, Fowler VG, Jezek A, Outterson K, Greenberg DE. Antibiotic resistance in the patient with cancer: Escalating challenges and paths forward. CA Cancer J Clin 2021; 71:488-504. [PMID: 34546590 DOI: 10.3322/caac.21697] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/23/2021] [Accepted: 08/12/2021] [Indexed: 12/13/2022] Open
Abstract
Infection is the second leading cause of death in patients with cancer. Loss of efficacy in antibiotics due to antibiotic resistance in bacteria is an urgent threat against the continuing success of cancer therapy. In this review, the authors focus on recent updates on the impact of antibiotic resistance in the cancer setting, particularly on the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.). This review highlights the health and financial impact of antibiotic resistance in patients with cancer. Furthermore, the authors recommend measures to control the emergence of antibiotic resistance, highlighting the risk factors associated with cancer care. A lack of data in the etiology of infections, specifically in oncology patients in United States, is identified as a concern, and the authors advocate for a centralized and specialized surveillance system for patients with cancer to predict and prevent the emergence of antibiotic resistance. Finding better ways to predict, prevent, and treat antibiotic-resistant infections will have a major positive impact on the care of those with cancer.
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Affiliation(s)
- Amila K Nanayakkara
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, University of Texas Southwestern, Dallas, Texas
| | - Helen W Boucher
- Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Boston, Massachusetts
| | - Vance G Fowler
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Amanda Jezek
- Infectious Diseases Society of America, Arlington, Virginia
| | - Kevin Outterson
- CARB-X, Boston, Massachusetts
- Boston University School of Law, Boston, Massachusetts
| | - David E Greenberg
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, University of Texas Southwestern, Dallas, Texas
- Department of Microbiology, University of Texas Southwestern, Dallas, Texas
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23
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Sood G, Perl TM. Outbreaks in Health Care Settings. Infect Dis Clin North Am 2021; 35:631-666. [PMID: 34362537 DOI: 10.1016/j.idc.2021.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Outbreaks and pseudo-outbreaks in health care settings are complex and should be evaluated systematically using epidemiologic and molecular tools. Outbreaks result from failures of infection prevention practices, inadequate staffing, and undertrained or overcommitted health care personnel. Contaminated hands, equipment, supplies, water, ventilation systems, and environment may also contribute. Neonatal intensive care, endoscopy, oncology, and transplant units are areas at particular risk. Procedures, such as bronchoscopy and endoscopy, are sources of infection when cleaning and disinfection processes are inadequate. New types of equipment can be introduced and lead to contamination or equipment and medications can be contaminated at the manufacturing source.
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Affiliation(s)
- Geeta Sood
- Division of Infectious Diseases, Johns Hopkins University School of Medicine, Johns Hopkins Bayview Medical Center, Mason F. Lord Building, Center Tower, 3rd Floor, 5200 Eastern Avenue, Baltimore, MD 21224, USA.
| | - Trish M Perl
- Division of Infectious Diseases and Geographic Medicine, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Y7;302, Dallas, TX 75390, USA
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Surveillance cultures following a regional outbreak of carbapenem-resistant Acinetobacter baumannii. Infect Control Hosp Epidemiol 2021; 43:454-460. [PMID: 33985611 DOI: 10.1017/ice.2021.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVES The primary aim of this study was to assess the epidemiology of carbapenem-resistant Acinetobacter baumannii (CRAB) for 9 months following a regional outbreak with this organism. We also aimed to determine the differential positivity rate from different body sites and characterize the longitudinal changes of surveillance test results among CRAB patients. DESIGN Observational study. SETTING A 607-bed tertiary-care teaching hospital in Milwaukee, Wisconsin. PATIENTS Any patient admitted from postacute care facilities and any patient housed in the same inpatient unit as a positive CRAB patient. METHODS Participants underwent CRAB surveillance cultures from tracheostomy secretions, skin, and stool from December 5, 2018, to September 6, 2019. Cultures were performed using a validated, qualitative culture method, and final bacterial identification was performed using mass spectrometry. RESULTS In total, 682 patients were tested for CRAB, of whom 16 (2.3%) were positive. Of the 16 CRAB-positive patients, 14 (87.5%) were residents from postacute care facilities and 11 (68.8%) were African American. Among positive patients, the positivity rates by body site were 38% (6 of 16) for tracheal aspirations, 56% (9 of 16) for skin, and 82% (13 of 16) for stool. CONCLUSIONS Residents from postacute care facilities were more frequently colonized by CRAB than patients admitted from home. Stool had the highest yield for identification of CRAB.
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Feasibility and potential significance of rapid in vitro qualitative phenotypic antimicrobial susceptibility testing of gram-negative bacilli with the ProMax system. PLoS One 2021; 16:e0249203. [PMID: 33770124 PMCID: PMC7996979 DOI: 10.1371/journal.pone.0249203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/15/2021] [Indexed: 11/23/2022] Open
Abstract
The emergence and evolution of antibiotic resistance has been accelerated due to the widespread use of antibiotics and a lack of timely diagnostic tests that guide therapeutic treatment with adequate sensitivity, specificity, and antimicrobial susceptibility testing (AST) accuracy. Automated AST instruments are extensively used in clinical microbiology labs and provide a streamlined workflow, simplifying susceptibility testing for pathogenic bacteria isolated from clinical samples. Although currently used commercial systems such as the Vitek2 and BD Phoenix can deliver results in substantially less time than conventional methods, their dependence on traditional AST inoculum concentrations and optical detection limit their speed somewhat. Herein, we describe the GeneFluidics ProMax lab automation system intended for a rapid 3.5-hour molecular AST from clinical isolates. The detection method described utilizes a higher starting inoculum concentration and automated molecular quantification of species-specific 16S rRNA through the use of an electrochemical sensor to assess microbiological responses to antibiotic exposure. A panel of clinical isolates consisting of species of gram-negative rods from the CDC AR bank and two hospitals, New York-Presbyterian Queens and Medical College of Wisconsin, were evaluated against ciprofloxacin, gentamicin, and meropenem in a series of reproducibility and clinical studies. The categorical agreement and reproducibility for Citrobacter freundii, Enterobacter cloacae, Escherichia coli, Klebsiella aerogenes, Klebsiella oxytoca, Klebsiella pneumoniae, and Pseudomonas aeruginosa were 100% and 100% for ciprofloxacin, 98.7% and 100% for gentamicin and 98.5% and 98.5% for meropenem, respectively.
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