Characteristics of Carbapenem-Resistant Gram-Negative Bacilli in Patients with Ventilator-Associated Pneumonia

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.

Download Full-text

Epidemiological characteristics and antimicrobial susceptibility among carbapenem-resistant non-fermenting bacteria in Brazil

The Journal of Infection in Developing Countries ◽

10.3855/jidc.6640 ◽

2016 ◽

Vol 10 (06) ◽

pp. 544-553 ◽

Cited By ~ 7

Author(s):

Vanessa Cordeiro Dias ◽

Claudio Galuppo Diniz ◽

Ana Claudia de Oliveira Peter ◽

Andre Netto Bastos ◽

Victor Quinnet de Andrade Bastos ◽

...

Keyword(s):

Genetic Markers ◽

Antimicrobial Susceptibility ◽

Carbapenem Resistance ◽

Diffusion Method ◽

Resistant Bacteria ◽

Disk Diffusion Method ◽

Gram Negative ◽

Carbapenem Resistant ◽

Acinetobacter Spp ◽

Epidemiological Characteristics

Introduction: Non-fermenting Gram-negative bacteria such as Pseudomonas aeruginosa and Acinetobacter baumannii are widespread in the environment and are increasingly associated with nosocomial infections. Extensive and indiscriminate use of antibiotics in hospitals has contributed to an increased number of infections caused by these microorganisms, that are resistant to a wide variety of antimicrobials, including β-lactams. This study aimed to isolate and identify carbapenem-resistant Acinetobacter spp. and P. aeruginosa from hospitalized patients, to determine their antimicrobial susceptibility patterns and to screen for blaOXA-23, blaOXA-24, blaOXA-51, blaOXA-58, and blaOXA-143 genes among the isolated bacteria. Methodology: Antimicrobial resistance patterns were performed using the disk-diffusion method. Genetic markers related to carbapenem resistance were screened by polymerase chain reaction. Results: Carbapenem-resistant Acinetobacter spp. (n = 44) and P. aeruginosa (n = 28) samples were isolated from patients admitted to a tertiary hospital. Polymyxin B was the only effective drug for all isolates. Considering the oxacillinase gene screening, genetic markers were observed only in Acinetobacter isolates. The most frequent genotype observed was blaOXA-23+/blaOXA-51+ (45.5%), followed by blaOXA-51+/blaOXA-143+ (41%). The oxacillinase genes blaOXA-24 and blaOXA-58 were not detected. High mortality rates (> 70%) were observed. Conclusions: The data suggest the need for rational use of antimicrobials associated with early diagnosis of multidrug-resistant bacteria, especially considering non-fermenting Gram-negative rods, which are widespread in hospitals. The findings of blaoxa-51‑ strains suggest the occurrence and spread of non-A. baumannii species throughout our hospitals. Effective implementation of surveillance programs in hospitals is needed to reduce infectious and resistant intra- and inter-species bacteria.

Download Full-text

Prevalence of SHV-extended spectrum β-lactamase producing carbapenem –resistantKlebsiellapneumoniae among patients with lower respiratory tractinfections in Babylon Province-Iraq.

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v9ispl1.1299 ◽

2018 ◽

Vol 9 (SPL1) ◽

Author(s):

Fatima Moeen Abbas

Keyword(s):

Resistance Rate ◽

Combination Method ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

Extended Spectrum ◽

Pcr Method ◽

Polymerase Chain ◽

Tract Infections ◽

Positive Results

This study was carried out to screen the prevalence of Klebsiella pneumoniae isolated from patients with lower respiratory tract infections in Babylon province.From December,2015 to the end of March,2016,a total of 100 sputum samples were collected from patients visited or hospitalized Merjan Teaching Hospital and Al- Hashimya General Hospital. Fifteenth (65%) isolates were identified as Klebsiellapneumoniae. All bacterial isolates were evaluated for extended spectrum β-lactamase (ESBL) production phenotypically using disk combination method. Eleven (73.3%) isolates were detected as ESBL-producers. Kirby-Bauer disk diffusion method was employed to determine resistance profile of ESBLs-positive isolates. Higher rates of resistance were observed for ampicillin and piperacillin antibiotics with (81.8%) and (72.7%) resistance rate, respectively, while the lowest rate was noticed for imipenem antibiotic (14.28%). Carbapenem-resistant isolates were investigated for blaSHV gene by Polymerase Chain Reaction (PCR) method, 2 (100%) isolates gave positive results.

Download Full-text

Phenotypic and genotypic characterization of multidrug-resistant isolates from patients with catheter-associated urinary tract infection in a tertiary care hospital

Journal of Laboratory Physicians ◽

10.4103/jlp.jlp_22_19 ◽

2019 ◽

Vol 11 (03) ◽

pp. 206-211

Author(s):

Jaison Jayakaran ◽

Nirupa Soundararajan ◽

Priyadarshini Shanmugam

Keyword(s):

Urinary Tract ◽

Tertiary Care Hospital ◽

Tertiary Care ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Diffusion Method ◽

Care Hospital ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

Tract Infections

Abstract INTRODUCTION: Urinary tract infections (UTIs) remain as the most common infection. Catheter-associated (CA) UTI can lead to bacteremia and thereby is the leading cause of morbidity and mortality in hospitalized patients in our country. AIMS AND OBJECTIVES: This study aims to check the prevalence of CAUTI and study the phenotypic and genotypic characters of the multidrug-resistant organisms in a tertiary care hospital, with special reference to NDM-1 and OXA-23. MATERIALS AND METHODS: A total of 231 urine samples from patients with CA-UTI in different wards in a tertiary care hospital over a period of 3 months between June and August 2018 were collected and processed following the standard protocol. Antibiotic susceptibility tests were performed by disk-diffusion method. Modified Hodge test (MHT) was done to isolate carbapenem-resistant isolates, and polymerase chain reaction was done to detect NDM-1 and OXA-23. RESULTS: Out of 231 samples, 101 samples yielded significant growth. These 38 samples were Gram-negative bacilli which were resistant to carbapenems. Out of the 38 which showed carbapenem resistance, 23 were MHT positive. Out of the 23 MHT-positive isolates, 8 (21.05%) were positive for NDM-1 gene and only 1 (2.6%) was positive for the OXA-23 gene. CONCLUSION: This study has shown that carbapenem-resistant isolates from all the CA urinary tract-infected patients were 52.77% and most of them were Klebsiella. About 21% of them harbored the NDM-1 gene whereas only 2% had the OXA-23 gene. There has been an alarming increase in the spread of carbapenem resistance.

Download Full-text

Detection of Pan drug resistance OXA-48 producing Providencia in an ICU patient for the first time in Nepal

Antimicrobial Resistance and Infection Control ◽

10.1186/s13756-019-0608-1 ◽

2019 ◽

Vol 8 (1) ◽

Cited By ~ 3

Author(s):

Ranjit Sah ◽

Shusila Khadka ◽

Gentle Sunder Shrestha ◽

Subhash Acharya ◽

Diptesh Aryal ◽

...

Keyword(s):

Drug Resistance ◽

Pathogenic Bacteria ◽

Antimicrobial Agents ◽

Vital Signs ◽

Carbapenem Resistance ◽

Diffusion Method ◽

Resistance Pattern ◽

Common Mechanism ◽

Disk Diffusion Method ◽

Drug Resistance Pattern

Abstracts Background Resistance to antimicrobial agents of pathogenic bacteria has become a major problem in routine medical practices. Carbapenem resistance has long been increasing. The production of carbapenem- hydrolysing β-lactamases (carbapenamases), which include NDM, KPC, OXA-48, IMP-1 and VIM is the most common mechanism. Case presentation A 56 years old male presented with fever and mental changes with progressively decreasing sensorium for the last 3 days. He was admitted to Intensive care unit (ICU) with a diagnosis of meningoencephalitis. On day seven, he developed ventilator associated pneumonia due Klebsiella pnemoniae and Acinetobacter baumannii. He was on meropenem, but the isolates were susceptible to colistin, tigecyclin and amikacin solely. Hence, amikacin was started with addition of intravenous and nebulized colistin. Subsequently, vital signs improved with resolution of fever. However, on day 18, he developed fever once again with a drop in blood pressure. Inotropic support was maintained, and echinocandins and tigecycline were added to the regimen. Repeat blood and urine culture grew Providencia species, which were resistant to most of the drugs on phenotypic Kirby-Bauer disk diffusion method and are intrinsically resistant to colistin and tigecycline. Phenotypic detection of ESBL (combined disk method), MBL, KPCs, AmpC and co-producer were tested according to updated CLSI guideline and all were negative. But the Modified Hodges test was found to be positive. Consequenty, OXA-48 drug resistance pattern was brought into action by blank disc method according to A Tsakris et al., which revealed indentation of growth toward both EDTA and EDTA/PBA disk indicating production of OXA-48 carbapenamase. To confirm the resistance pattern we processed the isolated colonies for Xpert Carba-R (Cepheid) assay, which detected blaOXA-48 gene and confirmed the OXA-48 drug resistance pattern. Hence, the infecting organism was not susceptible to any of the antibiotics. The patient was kept under isolation and on 31th day of admission, he died of septic shock. Conclusions Carbapenamase production along with intrinsic colistin resistance in infecting bacterial pathogens can cause fatal outcomes in the resource limited countries like Nepal where new antibiotic combinations ceftazidime+ Avibactam, or aztreonam +avibactam are not available. Drug resistance patterns including OXA 48 producer should be characterized in all cases by standard phenotypic methods or by Xpert Carba-R assay and larger studies are required to know the exact burden of OXA 48 producer in Nepal.

Download Full-text

Prevalence, resistance to antimicrobials, and antibiotypes of Arcobacter species recovered from retail meat in Wasit marketplaces in Iraq

International Journal of One Health ◽

10.14202/ijoh.2021.142-150 ◽

2021 ◽

Vol 7 (1) ◽

pp. 142-150

Author(s):

Manal H. G. Kanaan

Keyword(s):

Public Health ◽

Management Practices ◽

Resistance Index ◽

Resistance Rate ◽

Health Concern ◽

Diffusion Method ◽

Identification System ◽

Global Public Health ◽

Disk Diffusion Method ◽

Retail Meat

Background and Aim: Arcobacter is a food-borne pathogen associated with human and animal infections. In Iraq, these infections and their adverse effects on public health have not been well investigated. For this reason, as well as to submit data on the resistance to antimicrobials and antibiotypes of the Arcobacter spp. and their occurrence in retail meat in the Wasit marketplaces, this study was undertaken. Materials and Methods: A total of 83 samples of fresh raw (n=35) and chilled meat (n=48) were purchased randomly from marketplaces in various regions of the Wasit Governorate. Bacterial detection was conducted using cultural methods, biochemical analysis, and the Oxoid Biomedical Identification System Campy. Confirmation of these bacteria at the species level was performed using the multiplex polymerase chain reaction method. Susceptibility of the Arcobacter spp. to antimicrobials was investigated in 11 isolates comprising Arcobacter butzleri (n=9) and Arcobacter cryaerophilus (n=2) using the Kirby–Bauer disk diffusion method. Results: A total of 32 (38.6%) of the 83 fresh raw and chilled meat samples tested positive for Arcobacter spp.; of those, 27 (84.4%) and 5 (15.6%) were recognized as A. butzleri and A. cryaerophilus, respectively. Maximum resistance was perceived, respectively, to tetracycline, erythromycin, and ampicillin (90.9%, 81.8%, and 81.8%, respectively). In contrast, a low resistance rate against fluoroquinolones up to 9.09% was found. Antibiograms of the A. butzleri and A. cryaerophilus isolates yielded ten antibiotypes. The vast majority of the isolates (90.91%) were resistant to no fewer than three classes of antimicrobials, and 27.3% of these showed resistance to six antibiotics. A total of 91% of the analyzed isolates had a multiple antibiotic resistance index score between 0.27 and 0.73. Conclusion: Our outcomes demonstrated that retail meat can be a prospective vehicle for pathogenic Arcobacter, making these products a possible risk to human health. Our outcomes postulate that the contamination of retail meats by pathogenic Arcobacter is a global public health concern, particularly with the growing resistance to life-saving drugs, and emphasizes consumer understanding about the quality and safety of these products. To achieve healthy food products, good management practices, and successful control approaches must be implemented across the entire food chain, not only to protect consumers from these contaminants but also to minimize the risk of drug resistance.

Download Full-text

Prevalence and Characteristics of Metallo-beta Lactamase-positive and High-risk Clone ST235 Pseudomonas aeruginosa at Ardabil Hospitals

Jundishapur Journal of Microbiology ◽

10.5812/jjm.115819 ◽

2021 ◽

Vol 14 (3) ◽

Author(s):

Somayeh Safarirad ◽

Mohsen Arzanlou ◽

Jafar Mohammadshahi ◽

Hamid Vaez ◽

Amirhossin Sahebkar ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Continuous Monitoring ◽

Multidrug Resistant ◽

Resistance Rate ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

Clonal Relatedness ◽

Synergy Test ◽

Highly Virulent

Background: Carbapenems are the most commonly administered drugs for the treatment of multidrug-resistant Pseudomonas aeruginosa (MDR-P. aeruginosa) infections. However, carbapenem-resistant P. aeruginosa is spreading rapidly and has led to a new threat to human health worldwide. Objectives: The current study aimed to determine the prevalence of imipenem-resistant P. aeruginosa, detect metallo-β-lactamase (MBL)-producer isolates, and evaluate their clonal relationships in strains isolated from patients referring to the hospitals of Ardabil city, Iran. Methods: The resistance rate to imipenem was evaluated using the disk diffusion method. Double-disk synergy test and PCR technique were used for phenotypic and genotypic screening of MBL-positive P. aeruginosa, respectively. Ultimately, ERIC-PCR and MLST methods were used for assessing clonal relatedness among the isolates. Results: The prevalence of imipenem-resistant P. aeruginosa strains was estimated at 57.1% (48 out of 84 isolates). In addition, 45 (93.7%) out of 48 imipenem-resistant P. aeruginosa isolates were phenotypically screened as MBL-positive, among which 16 (35.5%) and three (6.6%) isolates harbored blaIMP and blaVIM-1 genes, respectively. However, blaNDM, blaSIM-2, blaSPM, and blaGIM-1 genes were not detected in this study. MBL-producing P. aeruginosa strains were divided into 42 ERIC-PCR types. Based on the results of MLST, P. aeruginosa ST235 was the only identified sequence type. Conclusions: Our results revealed a high and alarming prevalence of imipenem-resistant and blaIMP-positive P. aeruginosa ST235 at Ardabil hospitals. Continuous monitoring is essential to control the further spread of this highly virulent and drug-resistant clone.

Download Full-text

Emergence of OXA-10 and OXA-48 like carbapenemases among Enterobacter isolates from inpatients in southern Iran

10.21203/rs.3.rs-673753/v1 ◽

2021 ◽

Author(s):

Melika Moradi ◽

Reza Khashei ◽

Yalda Malekzadegan ◽

Jamal Sarvari

Keyword(s):

Carbapenem Resistance ◽

Common Species ◽

Resistance Rate ◽

Health Concern ◽

Multi Drug Resistance ◽

Class 1 Integron ◽

Carbapenem Resistant ◽

Microbiological Methods ◽

Global Spread ◽

Class 1

Abstract Background The global spread of carbapenemase-producing Enterobacteriaceae represents a public health concern. The aim of this study was to investigate prevalence of carbapenem resistance, oxacillinase types and the presence of class 1–3 integrons among Enterobacter clinical isolates from an Iranian inpatients’ population. Methods Ninety Enterobacter isolates recovered from hospitalized patients were diagnosed by the standard microbiological methods. Antibiogram pattern was also determined. The presence of class 1–3 integrons and four types of oxacillinase genes were assessed using PCR. Results Of the 90 Enterobacter isolates, the most common species was identified as E. aerogenes, (45.6%), followed by E. cloacae (30%). The highest resistance rate was against to ampicillin (96.7%). Multi-drug resistance (MDR) was substantial (93%). Carbapenemase producers were detected in 96% of carbapenem resistant isolates by mCIM test. The frequency of evaluated genes was as follows: intI1 = 50 (55.6%), intI2 = 12 (13.3%), blaoxa−1 =6 (6.7%), blaoxa−2 =5 (5.6%), blaoxa−10 =18 (20%), and blaoxa−48 =18 (20%). Conclusion The determinants of class 1 integron with OXA-10 and OXA-48 like carbapememases have been responsible of relatively considerable of carbapenem resistance among isolates. This is the first OXA-10 and OXA-48-producing Enterobacter spp. in Iran, indicating that the prevalence of oxacillinases might be on the rise in country.

Download Full-text

Molecular Typing of Imipenem-ResistantAcinetobacter baumannii-calcoaceticusComplex in a Singapore Hospital Where Carbapenem Resistance Is Endemic

Infection Control and Hospital Epidemiology ◽

10.1086/518964 ◽

2007 ◽

Vol 28 (8) ◽

pp. 941-944 ◽

Cited By ~ 2

Author(s):

Thean Yen Tan ◽

Karen Poh ◽

Siew Yong Ng

Keyword(s):

Tertiary Care ◽

Carbapenem Resistance ◽

Diffusion Method ◽

Clinical Samples ◽

Care Hospital ◽

Typing Method ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

High Prevalence ◽

Resistant Strains

Objective.To investigate the molecular epidemiology of carbapenem-resistantAcinetobacter baumannii-calcoaceticuscomplex isolates in a tertiary care hospital where the prevalence of carbapenem resistance among these organisms is high.Design.The study was a prospective, observational study performed during an 8-month period (May 1 through December 31, 2004).A. baumanniiisolates recovered from all clinical samples during the study period were included in the study. Antibiotic susceptibility testing was performed using the disk diffusion method, and all carbapenem-resistant strains were typed by a polymerase chain reaction-based typing method.Setting.An 800-bed hospital in Singapore.Results.More than half of recovered isolates were clonally unrelated, with the remaining isolates grouped into 4 genotypes.Conclusions.The results of the study suggest that the high prevalence of carbapenem resistance amongAcinetobacterorganisms in this institution is not caused by the spread of a predominant clone and that other factors may need to be investigated.

Download Full-text

Ceftazidime/avibactam and eravacycline susceptibility of carbapenem-resistant Klebsiella pneumoniae in two Greek tertiary teaching hospitals

Acta Microbiologica et Immunologica Hungarica ◽

10.1556/030.2021.01364 ◽

2021 ◽

Author(s):

Maria Chatzidimitriou ◽

Panagiota Chatzivasileiou ◽

Georgios Sakellariou ◽

MariaAnna Kyriazidi ◽

Asimoula Kavvada ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Antimicrobial Agents ◽

Carbapenem Resistance ◽

Teaching Hospitals ◽

Diffusion Method ◽

Strain Identification ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

Tertiary Teaching

AbstractThe present study evaluated the carbapenem resistance mechanisms of Klebsiella pneumoniae strains isolated in two Greek tertiary teaching hospitals and their susceptibility to currently used and novel antimicrobial agents.Forty-seven carbapenem resistant K. pneumoniae strains were collected in G. Papanikolaou and Ippokrateio hospital of Thessaloniki between 2016 and 2018. Strain identification and antimicrobial susceptibility was conducted by Vitek 2 system (Biomérieux France). Susceptibility against new antimicrobial agents was examined by disk diffusion method. Polymerase chain reaction (PCR) was used to detect blaKPC, blaVIM, blaNDM and blaOXA-48 genes.The meropenem–EDTA and meropenem–boronic acid synergy test performed on the 24 K. pneumoniae strains demonstrated that 8 (33.3%) yielded positive for metallo-beta-lactamases (MBL) and 16 (66.6%) for K. pneumonia carbapenemases (KPC) production. Colistin demonstrated the highest in vitro activity (87.7%) among the 47 K. pneumoniae strains followed by gentamicin (76.5%) and tigecycline (51%). Among new antibiotics ceftazidime/avibactam showed the highest sensitivity (76.6%) in all strains followed by eravacycline (66.6%). The blaKPC gene was present in 30 strains (63.8%), the blaNDM in 11 (23.4%) and the blaVIM in 6 (12.8%). The blaOXA-48 gene was not detected.Well established antimicrobial agents such as colistin, gentamicin and tigecycline and novel antibiotics like ceftazidime/avibactam and eravacycline can be reliable options for the treatment of invasive infections caused by carbapenem-resistant K. pneumoniae.

Download Full-text

Colistin and Carbapenem-Resistant Acinetobacter baumannii Aci46 in Thailand: Genome Analysis and Antibiotic Resistance Profiling

Antibiotics ◽

10.3390/antibiotics10091054 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1054

Author(s):

Nalumon Thadtapong ◽

Soraya Chaturongakul ◽

Sunhapas Soodvilai ◽

Padungsri Dubbs

Keyword(s):

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Antibiotic Resistance Genes ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Diffusion Method ◽

Whole Genome ◽

Disk Diffusion Method ◽

Genome Data ◽

Carbapenem Resistant

Resistance to the last-line antibiotics against invasive Gram-negative bacterial infection is a rising concern in public health. Multidrug resistant (MDR) Acinetobacter baumannii Aci46 can resist colistin and carbapenems with a minimum inhibitory concentration of 512 µg/mL as determined by microdilution method and shows no zone of inhibition by disk diffusion method. These phenotypic characteristics prompted us to further investigate the genotypic characteristics of Aci46. Next generation sequencing was applied in this study to obtain whole genome data. We determined that Aci46 belongs to Pasture ST2 and is phylogenetically clustered with international clone (IC) II as the predominant strain in Thailand. Interestingly, Aci46 is identical to Oxford ST1962 that previously has never been isolated in Thailand. Two plasmids were identified (pAci46a and pAci46b), neither of which harbors any antibiotic resistance genes but pAci46a carries a conjugational system (type 4 secretion system or T4SS). Comparative genomics with other polymyxin and carbapenem-resistant A. baumannii strains (AC30 and R14) identified shared features such as CzcCBA, encoding a cobalt/zinc/cadmium efflux RND transporter, as well as a drug transporter with a possible role in colistin and/or carbapenem resistance in A. baumannii. Single nucleotide polymorphism (SNP) analyses against MDR ACICU strain showed three novel mutations i.e., Glu229Asp, Pro200Leu, and Ala138Thr, in the polymyxin resistance component, PmrB. Overall, this study focused on Aci46 whole genome data analysis, its correlation with antibiotic resistance phenotypes, and the presence of potential virulence associated factors.

Download Full-text