Antibiotic resistance in uropathogenic enterobacteria

Multidrug-resistant Enterobacteriaceae are a major public health threat worldwide. These germs are the most redoubtable because they are producers of beta-lactamases and possess other mechanisms of resistance to many antibiotics. The objective of this work is to identify isolated strains of Enterobacteriaceae and to study their antibiotic resistance profiles, thus contributing to the surveillance of antibioresistance. This is a retrospective study over a period of three years (2018-2020) including urine samples taken in the region of Rabat-Salé-Zaire and examined at the laboratory of Epidemic Diseases in National Institute of Hygiene of Rabat. Enterobacteriaceae were the most frequent germs with a predominance of Escherichia coli (68%) followed by Klebsiella pneumoniae (23%). Extended-spectrum beta-lactamase-producing Enterobacteriaceae accounted for 10.5%. The highest resistance was observed with amoxicillin, followed by ticarcillin, cefalotin, trimethoprim/sulfamethoxazole, amoxicillin+clavulanic acid, nalidixic acid and finally ciprofloxacin and norfloxacin. The aminoglycosides and the 2nd and 3rd cephalosporins were the most active molecules. The sensitivity of imipenem and ertapenem was 100%. This study shows the worrying appearance of resistance to the usual antibiotics in uropathogenic enterobacteria. Rational prescription of antibiotics and monitoring of the evolution of bacterial resistance are necessary in each region.

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Occurrence and Characteristics of the Extended-spectrum Beta-lactamase-producing Enterobacterale in a Hospital Setting

The Open Microbiology Journal ◽

10.2174/1874285802014010190 ◽

2020 ◽

Vol 14 (1) ◽

pp. 190-195

Author(s):

Salah H. Elsafi

Keyword(s):

Dominant Gene ◽

Hospital Costs ◽

Hospital Setting ◽

Beta Lactamase ◽

M Gene ◽

Antibiotic Resistant ◽

Extended Spectrum Beta Lactamase ◽

Public Health Threat ◽

Amoxicillin Clavulanic Acid ◽

Susceptibility Tests

Objectives: Infectious diseases caused by ESBL-producing Enterobacterale are an emerging problem worldwide, which increase hospital costs, empirical treatment failure, together with rates of morbidity and mortality. The aims of this study were to determine the antibiotic-resistant patterns and the frequency of blaTEM, blaCTX-M and blaSHV genes among Enterobacterale. Methods: A total of 239 non-repeated clinical isolates of the Enterobacterale family, including 202 (84.5%) Escherichia coli and Klebsiella pneumoniae 25 (12.3%) were collected. Identification and susceptibility tests were carried out on 60 (25.9%) ESBL phenotypes using biomérieux VITEK® 2 compact system. Isolates showing ESBL positivity by the phenotypic method were all screened for blaTEM, blaCTX-M and blaSHV genes by PCR. Results: The prevalence of ESBL-producing Enterobacterale isolates was found to be 25.9%. These ESBL-producing isolates displayed an increasing rate of resistance for aminopenicillins (ampicillin) (96.3%), followed by piperacillin-tazobactam (54.2%), amoxicillin/clavulanic acid (45.8), the cephalosporin groups, ceftriaxone (52.4%), ceftazidime (46.7%), and fluoroquinolone (ciprofloxacin) (42.7%). Both the organisms showed a higher susceptibility to the carbapenems (Imipenem) and aminoglycosides (Amikacin). Out of the 62 ESBL positive isolates, 11 (17.7%) carried the TEM gene, 22 (35.5%) carried the CTX-M gene alone, 8 (12.9%) carried both TEM and CTX-M genes, 1(1.6%) carried both SHV and CTX-M genes, and 20 (32.3%) carried the TEM, SHV, and CTX-M genes. SHV gene alone was not reported in any of the isolates. Conclusion: The study indicated a moderate occurrence of ESBL-producing Enterobacterale with CTX-M being the most dominant gene. The co-existence of all three genes on many occasions suggested the carriage of multiple plasmids with three resistance genes that might pose a serious epidemiological, clinical and public health threat.

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The Frequency of Antibiotic Resistance and ESBLs Among Clinically Acinetobacter baumannii Strains Isolated from Patients in a Major Hospital in Tehran, Iran

The Open Microbiology Journal ◽

10.2174/1874285801812010254 ◽

2018 ◽

Vol 12 (1) ◽

pp. 254-260 ◽

Cited By ~ 3

Author(s):

Reza Ranjbar ◽

Sajjad S. Tolon ◽

Shahin Zayeri ◽

Mehrdad Sami

Keyword(s):

Antibiotic Resistance ◽

Acinetobacter Baumannii ◽

Bacterial Resistance ◽

Treatment Options ◽

Clinical Samples ◽

Limiting Factor ◽

Beta Lactamases ◽

Microbiological Methods ◽

Extended Spectrum Beta Lactamases ◽

Amoxicillin Clavulanic Acid

Background:Bacterial resistance to antibiotics limits treatment options, increases morbidity and mortality, and raises the risk of antibiotic-associated adverse events. Antibacterial resistance emerges rapidly following an increase in the consumption of antibiotics against infectious diseases. The spread of ESBL producing strains has a limiting factor based on antibiotic function for the treatment of infections particularly caused byAcinetobacter baumannii(A. baumannii).Objective:This study was conducted to evaluate the prevalence of antimicrobial resistance and distribution ofblaTEM,blaCTX, andblaSHVgenes amongA. baumanniistrains isolated from clinical samples at a major hospital in Teheran, Iran.Methods:A. baumanniistrains were isolated and identified using standard microbiological methods. The disc diffusion and combined discs methods were used for testing antimicrobial susceptibility and to identify the strains producing Extended-Spectrum Beta-Lactamases (ESBL), respectively. DNA extraction was done by boiling method. Finally, the frequency of resistant genes includingblaTEM,blaCTX, andblaSHVin ESBL producing isolates was studied by PCR.Results:Gender distribution in this study was 53 (53%) samples for men and 47 (47%) for women. Totally, one hundredA. baumanniistrains were isolated. More than 93% of the isolates were multi drug resistant. The highest to lowest antibiotic resistance was observed against amoxicillin/clavulanic acid (98%), ceftriaxone (96%), cefotaxime (94%), and ceftazidime (93%), respectively. The frequency of positive phenotypic test of ESBL was 19% and 16% for CAZ-C and CTX-C, respectively. The frequency ofblaTEM,blaCTX, andblaSHVgenes was 52.1, 43.4, and 21.7, respectively.Conclusion:A. baumanniiisolates exhibited an extremely worrying level of antibiotic resistance, and a high percentage of the isolates showed MDR in this study. This is a serious warning because ESBLs are a major threat to the effectiveness of antibiotics that are currently available for medical uses. The frequency of genes encoded ESBL isolates ofA. baumanniimay be due to overuse and misuse of antibiotics.

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A review on bacterial resistance to carbapenems: epidemiology, detection and treatment options

Future Science OA ◽

10.2144/fsoa-2019-0098 ◽

2020 ◽

Vol 6 (3) ◽

pp. FSO438 ◽

Cited By ~ 7

Author(s):

Ann A Elshamy ◽

Khaled M Aboshanab

Keyword(s):

Public Health ◽

Bacterial Resistance ◽

Antimicrobial Agents ◽

Treatment Options ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Mechanisms Of Resistance ◽

Carbapenem Resistant ◽

Public Health Threat ◽

Carbapenem Resistant Enterobacteriaceae

Carbapenems are a class of antimicrobial agents reserved for infections caused by multidrug-resistant microorganisms. The emergence of carbapenem resistance has become a serious public health threat. This type of antimicrobial resistance is spreading at an alarming rate, resulting in major outbreaks and treatment failure of community-acquired and nosocomial infections caused by the clinically relevant carbapenem-producing Enterobacteriaceae or carbapenem-resistant Enterobacteriaceae. This review is focused on carbapenem resistance, including mechanisms of resistance, history and epidemiology, phenotypic and genotypic detection in the clinically relevant bacterial pathogens and the possible treatment options available.

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Seagulls of the Berlengas Natural Reserve of Portugal as Carriers of Fecal Escherichia coli Harboring CTX-M and TEM Extended-Spectrum Beta-Lactamases

Applied and Environmental Microbiology ◽

10.1128/aem.00949-08 ◽

2008 ◽

Vol 74 (23) ◽

pp. 7439-7441 ◽

Cited By ~ 69

Author(s):

Patricia Poeta ◽

Hajer Radhouani ◽

Gilberto Igrejas ◽

Alexandre Gonçalves ◽

Carlos Carvalho ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Antibiotic Resistance Gene ◽

Beta Lactamase ◽

Beta Lactamases ◽

Extended Spectrum Beta Lactamase ◽

Extended Spectrum ◽

Natural Reserve ◽

Class 1 ◽

Extended Spectrum Beta Lactamases

ABSTRACT Escherichia coli isolates containing the following extended-spectrum beta-lactamases have been detected in 11 of 57 fecal samples (19.3%) in Berlengas Island seagulls: TEM-52 (eight isolates), CTX-M-1 (one isolate), CTX-M-14a (one isolate), and CTX-M-32 (one isolate). Most of the extended-spectrum beta-lactamase-positive isolates harbored class 1 or class 2 integrons, which included different antibiotic resistance gene cassettes.

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Beta-Lactamase-Producing Escherichia coli Isolates Recovered from Pig Handlers in Retail Shops and Abattoirs in Selected Localities in Southern Nigeria: Implications for Public Health

Antibiotics ◽

10.3390/antibiotics10010009 ◽

2020 ◽

Vol 10 (1) ◽

pp. 9

Author(s):

Olivia Sochi Egbule ◽

Benson C. Iweriebor ◽

Edward Ikenna Odum

Keyword(s):

Escherichia Coli ◽

Clavulanic Acid ◽

Multidrug Resistant ◽

Beta Lactamase ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Resistance Evolution ◽

Resistance Patterns ◽

Amoxicillin Clavulanic Acid ◽

And Gender

Antibiotic resistance evolution among pathogenic microorganisms has become a huge burden globally as it has increased the burden of diseases amongst humans and animals. The prevalence of extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-Ec) and metallo beta-lactamase-producing Escherichia coli (MBL-Ec) isolated from pig abattoir and handlers in retail shops was studied. In addition, the relationship between the isolates’ prevalence and the background characteristics of the butchers/retailers was also investigated. Samples from 32 hand swabs of pork sellers at retail shops and 8 butchers at abattoirs, as well as 272 swabs taken from knives, tables, floors, water troughs, and carcasses from both retail shops and abattoirs, were collected. Escherichia coli (E. coli) was isolated from hand swabs, fomites, and carcasses and were identified by standard microbiological procedures. The isolates susceptibility to nitrofurantoin (300 µg), ciprofloxacin (5 µg), ceftazidime (30 µg), cefuroxime (30 µg), gentamicin (10 µg), cefixime (5 µg), ofloxacin (5 µg), amoxicillin/clavulanic acid (30 µg), imipenem (10 µg), and meropenem (10 µg) and their ability to produce ESBL and MBL was determined by phenotypic methods. Demographic information of the handlers was retrieved by means of a structured questionnaire and, in some cases, via face to face interviews. Out of 104 E. coli isolates from both sources, 52 (50.0%) and 8 (7.7%) were ESBL and MBL producers, respectively. ESBL was more prevalent on the hands of the retailers (40.6%) and butchers (75.0%). The isolates were 100% resistant to ceftazidime, cefotaxime, and amoxicillin–clavulanic acid and 4.8% resistant to nitrofurantoin. Diverse resistance patterns were observed among ESBL-Ec and MBL-Ec. It was found that 90% of ESBL-Ec and 100% of MBL-Ec were multidrug-resistant. A possible epidemiological link between the two sources was observed. The prevalence of E. coli ESBL- and MBL-producing isolates was associated with the duty performed by handlers (p = 0.012) and gender (p = 0.012). Our results provide evidence that the handlers’ hands and abattoir environment had a great role to play in the high prevalence and resistance profiles of the microorganisms.

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Detection, identification and characterization of extended-spectrum beta-lactamases producing Enterobacteriaceae in wastewater and salads marketed in Ouagadougou, Burkina Faso

International Journal of Biological and Chemical Sciences ◽

10.4314/ijbcs.v14i8.8 ◽

2020 ◽

Vol 14 (8) ◽

pp. 2746-2757

Author(s):

Souleymane Soré ◽

Yacouba Sawadogo ◽

Juste Isidore Bonkoungou ◽

Sephora P. Kaboré ◽

Saidou Béogo ◽

...

Keyword(s):

Multidrug Resistant ◽

Diffusion Method ◽

Beta Lactamases ◽

Extended Spectrum Beta Lactamase ◽

Extended Spectrum ◽

Extended Spectrum Beta Lactamases ◽

Amoxicillin Clavulanic Acid ◽

Synergy Test ◽

Identification And Characterization

Extended spectrum beta-lactamase producing Enterobacteriaceae (ESBL-PE) represent a threat for failure of empirical antibiotic therapy and are associated with high mortality, morbidity and expenses. The aims of this study was to determine the prevalence of ESBL-PE and multidrug resistant enterobacteria (MDR), enterobacteria profil, investigate the associated resistance in wastewater and salads. After wastewater and salad sampling, enterobacteria was isoled on (EMB + 4μg / L cefotaxim). The stains of Enterobacteriaceae were identified by using biochemical methods and confirmed as ESBL by double-disc synergy test (amoxicillin/clavulanic acid with cefotaxime 30 μg, ceftazidime 30 μg and ceftriaxone 30 μg). Finally, the associated resistance was investigated by testing the susceptibility of the strains by the disc diffusion method. Global prevalence of ESBL-PE was 53.92% (95% CI: 48,2-59,5) (153/293), 61.11% from wastewater and 42.47% from salads. Major ESBL-E was Escherichia coli (73.44%), followed by Klebsiella pneumoniae (21.88%). Resistance to the aminoglycoside , fluroquinolonones and sulfonamides classes were dominant, observed in 53,83%, 93,86% and 98,95% of the isolates, respectively. The frequence of MDR was hight to channel1 (32,40%) and channel2 (26,26%). This study reports very worrying results. There is an urgent need to develop measures to monitor the spread of these multidrug-resistant strains.Keywords: Wastewater, ESBL-PE, Salads, Ouagadougou.

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Phenotypic Detection of Extended Spectrum Beta-lactamase Resistance of Escherichia coli from Patients Attending Selected Healthcare Facilities in Nasarawa State, Nigeria

South Asian Journal of Research in Microbiology ◽

10.9734/sajrm/2019/v4i330108 ◽

2019 ◽

pp. 1-10

Author(s):

R. H. Abimiku ◽

Y. B, Ngwai ◽

I. H. Nkene ◽

B. E. Bassey ◽

P. A. Tsaku ◽

...

Keyword(s):

Antibiotic Resistance ◽

Clavulanic Acid ◽

Age Groups ◽

Beta Lactamase ◽

Healthcare Facilities ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Extended Spectrum ◽

Microbiological Methods ◽

Amoxicillin Clavulanic Acid

Aims: This study investigated the phenotypic detection of extended spectrum beta-lactamase resistance of diarrheagenic E. coli isolated from diarrheic patients attending some major health facilities in Nasarawa State, Nigeria. Place and Duration of Study: Department of Microbiology, Nasarawa State University, P.M.B 1022, Keffi, Nasarawa State, Nigeria; between December, 2017 to March, 2019. Methodology: A total of 207 confirmed E. coli isolates from loose stool samples of patients with suspected cases of diarrhea (69 from Federal Medical Centre Keffi [MCK] 69 from General Hospital Akwanga [GHA] and 69 from Dalhatu Araf Specialist Hospital Lafia [DASHL]) were included in this study. Results: E. coli was isolated and identified using standard microbiological methods. The antibiotic susceptibility testing for the isolates was carried out and interpreted in accordance with Clinical and Laboratory Standards Institute protocol. Phenotypic detection of ESBL production in isolates resistant to ciprofloxacin, cefotaxime and ceftazidime) was carried out using double disc synergy test. The occurrence of E. coli was 100% in all the hospitals. Age groups 0-5 and 6-10 years have the highest occurrence than age group 35 – >45 years. Isolates from DASHL were more resistant to amoxicillin/clavulanic acid (86.9%), Streptomycin (75.0%) and sulphamethoxazole/trimethoprim (68.1%), isolates from FMCK were more resistant to amoxicillin/clavulanic acid (84.1%), sulphamethoxazole/trimethoprim (69.6%), isolates from GHA were more resistant to amoxicillin/clavulanic acid (85.5%) and sulphamethoxazole/trimethoprim (73.0%). Multiple antibiotic resistance (MAR) was observed with the order of occurrence: FMCK (98.6%) > DASHL (92.8%) > GHA (89.9%). The most common MAR index of 0.2 in DASHL was 0.4 (20.3%); FMCK was 0.4 (15.9%) and GHA was 0.3 (17.4%). The order of occurrence of classes of antibiotic resistance in E. coli isolates in DASHL was MDR (84.0%) ˃ XDR(7.2%) > PDR and NMDR (4.3%); in FMCK was MDR (91.3%) ˃ XDR(4.3%) ˃ NMDR (2.9%) and PDR(1.4%); and in GHA was MDR (88.8%) ˃ NMDR(5.8%) > XDR and PDR(2.9%). Detection rate of ESBL was 53.6% (30/207), distributed in relation to the location as DASHL (60.0%), FMCK (50.0%) and GHA (52.6%). Conclusion: Most of the isolates from the study locations were antibiotic resistance. Further studies on molecular detection of ESBL, diversity and characterization of the E. coli into pathotypes are ongoing.

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Multidrug-Resistance Genes in Pseudomonas aeruginosa from Wound Infections in a Tertiary Health Institution in Osogbo, Nigeria.

Infectious Disorders - Drug Targets ◽

10.2174/1871526520666200117112241 ◽

2020 ◽

Vol 20 ◽

Cited By ~ 1

Author(s):

Akinloye Ajibola Oluseye ◽

Adefioye O. Jose ◽

Adekunle O. Catherine ◽

Anomneze Benjamin Udodiri ◽

Makanjuola OB ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Antibiotic Resistance ◽

Resistance Genes ◽

Multidrug Resistant ◽

Diffusion Method ◽

Wound Infections ◽

Extended Spectrum Beta Lactamase ◽

Carbapenem Resistant ◽

Amoxicillin Clavulanic Acid ◽

Mar Index

Background: Multidrug Resistant Pseudomonas aeruginosa (MDRPA) is an ubiquitous opportunistic organism which poses a threat to the management of infections globally. Objectives: The objectives of the current research were to assess the antibiotic resistance profiles as well as Multiple Antibiotic Resistance (MAR) Index of clinical isolates of P. aeruginosa associated with wound infections. Presence of Extended Spectrum Beta Lactamase genes (bla CTX-M, bla SHV and bla TEM) and Carbapenemase genes (bla KPC and blaNDM) were also determined among the isolates. Methods: Swab samples were collected from 255 patients with wound infections. Bacterial identification was done by standard diagnostic tests. The identity of isolates were confirmed by detection of the exoA gene using the PCR technique. Antibiotic susceptibility testing and resistance profile was determined using disc diffusion method. Resistance genes were amplified by the PCR method. Results: A total of 235 (92.2%) bacterial isolates were recovered from the wounds of the 255 patients of these, 124 (52.8%) were Gram-negative bacilli while the remaining 111 (47.2%) were Gram-positive cocci. A total of 69 Pseudomonas aeruginosa strains were recovered from the wound specimens. Imipenem was the most effective antibiotic against these isolates (92.8% isolates were susceptible) while all isolates were resistant to Meropenem, Cefepime, Ticarcillin, Amoxicillin-clavulanic acid, Cefotaxime, Ampicillin and Cefpodoxime. All 69 Pseudomonas aeruginosa isolates were multidrug resistant (MDR). Of the isolates selected for PCR, all were positive for the TEM, CTX-M and SHV genes while, one third was blaKPC and blaNDM producers. Conclusion: This study demonstrated the a high prevalence of carbapenem-resistant strains of P. aeruginosa. Suggesting that there is an urgent need in Nigeria for the enactment and enforcement of policies and necessary laws restricting the availability and indiscriminate use of antibiotics.

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Phenotypic Characterization of Multidrug-resistant Escherichia Coli with Special Reference to Extended-spectrum-beta-lactamases and Metallo-beta-lactamases in a Tertiary Care Center

Journal of Nepal Medical Association ◽

10.31729/jnma.2768 ◽

2015 ◽

Vol 53 (198) ◽

pp. 83-88 ◽

Cited By ~ 1

Author(s):

Basudha Shrestha ◽

Shovita Shrestha ◽

Shyam Kumar Mishra ◽

Hari Prasad Kattel ◽

Tatsuya Tada ◽

...

Keyword(s):

Escherichia Coli ◽

Multidrug Resistance ◽

Resistance Mechanism ◽

Multidrug Resistant ◽

Confirmatory Test ◽

Beta Lactamase ◽

Beta Lactamases ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Extended Spectrum

Introduction: The increasing reports on extended-spectrum-beta-lactamase and metallo-betalactamase producing Escherichia coli have addressed a potential threat to global health since it is found to be highly resistance to most of the currently available antibiotics including carbapenems. The present study was aimed to determine the antibiogram of extended-spectrum-beta-lactamase and metallo-beta-lactamase producing MDR E. coli isolates from various clinical samples. Methods: This was a cross-sectional study conducted over a period of seven months (December 2013 to July 2014) at bacteriology laboratory of Tribhuvan University Teaching Hospital. A total of 250 clinical specimens (urine, pus, sputum, blood, body fluid, bile, tissue and central venous pressure line tip) were processed from inpatients, with multidrug-resistant Escherichia coli infections. Standard microbiological techniques were used for isolation and identification of the isolates. The presence of extended-spectrum-beta-lactamase was detected by phenotypic confirmatory test recommended by Clinical and Laboratory Standards Institute and imipenem (IMP) /EDTA combined disc method was performed to detect metallo-beta-lactamase mediated resistance mechanism. Results: We found high level of beta lactamase mediated resistance mechanism as part of multidrug resistance. Among 250 MDR isolates, 60% isolates were extended-spectrum-beta-lactamase producers and 17.2% isolates were metallo-beta-lactamase producers. Co-existence of extended-spectrum-betalactamase and metallo-beta-lactamase identified in 6.8% isolates. Conclusions: Beta-lactamase mediated resistance mechanisms are accounting very high in the multidrug resistant isolates of E. coli. Therefore, early detection of beta lactamase mediated resistant strains and their current antibiotic susceptibility pattern is necessary to avoid treatment failure and prevent the spread of MDR. Keywords: e. coli; extended-spectrum-β-lactamase; metallo-β-lactamase; multidrug-resistance.

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Phenotypic and genotypic characterization of carbapenem resistance mechanisms in Klebsiella pneumoniae from blood culture specimens: A study from North India

Journal of Laboratory Physicians ◽

10.4103/jlp.jlp_155_16 ◽

2018 ◽

Vol 10 (02) ◽

pp. 125-129 ◽

Cited By ~ 1

Author(s):

Varsha Gupta ◽

Ritu Garg ◽

Karthikeyan Kumaraswamy ◽

Priya Datta ◽

Gursimran Kaur Mohi ◽

...

Keyword(s):

Blood Culture ◽

Klebsiella Pneumoniae ◽

Carbapenem Resistance ◽

North India ◽

Beta Lactamase ◽

Mechanisms Of Resistance ◽

Beta Lactamases ◽

Extended Spectrum Beta Lactamase ◽

Extended Spectrum ◽

Geographical Regions

ABSTRACT BACKGROUND: Emergence of carbapenem resistance among Enterobacteriaceae in different geographical regions is of great concern as these bacteria are easily transmissible among patients. Carbapenem-resistance in Enterobacteriaceae is due to production of carbapenemases of various classes and hyper production of the ESBLs (Extended spectrum beta lactamases) and Amp C beta lactamases with reduced cell wall permeability mechanisms. Phenotypic detection and differentiation is important for proper infection control and appropriate patient management. This study was done to know the prescence of various beta lactamases and carbapenemases with other mechanisms of resistance in Klebsiella pneumoniae isolates. MATERIALS AND METHODS: 50 non-duplicate carbapenem resistant isolates of Klebsiella pneumoniae from blood culture specimens were included and various mechanisms of resistance were studied based on phenotypic and genotypic methods. RESULTS: Out of 50 isolates, 39 (78%) of K.pneumoniae isolates were Extended Spectrum Beta Lactamase (ESBL) producers based on CLSI guidelines. All 50 showed positive Modified Hodge Test (MHT ) and 32 showed Metallo Beta Lactamase (MBL) by Combined Disc Test (CDT). Four isolates showed AmpC production with porin loss . None of the isolates showed Class A KPC production by CDT . In our study all the 10 isolates evaluated by genotypic technique produced CTX-M group 1 enzyme by multiplex PCR. Seven out of 10 strains which showed positive MBL results were positive for NDM . CONCLUSIONS: Carbapenems are often considered last resort antibiotics in the treatment of infections due to multidrug-resistant organisms. It is therefore mandatory to maintain the clinical efficacy of carbapenems by early detection of various enzymes . For routine clinical laboratories both phenotypic and genotypic tests need to be followed to detect various mechanisms of carbapenem resistance and this is of epidemiological relevance also.

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