scholarly journals Evaluation of cefoxitin disc diffusion test as a rapid phenotypic method for detection of methicillin resistance

2021 ◽  
Vol 8 (3) ◽  
pp. 215-218
Author(s):  
Anandkumar H ◽  
Jyothi U S ◽  
Rajeshwari R S

: Accuracy and promptness in the detection of methicillin resistance are of key importance in ensuring correct antibiotic treatment in infected patients and control of MR staphylococci in the hospital environment. The aim of this study was to detect MRSA phenotypically by oxacillin screen agar and Oxacillin MIC method and to evaluate cefoxitin disc diffusion test as a screening tool for MRSA detection. In the present study, a total of 50 isolates of from various clinical samples collected were used for the detection of Methicillin resistant (MRSA). Methicillin resistance was determined by oxacillin disc diffusion, cefoxitin disc diffusion the oxacillin screen agar test and MIC. Out of 50 isolates 21 (42%) isolates were detected as MRSA based on MIC method, which is considered as gold standard method for the detection of MRSA. All the isolates of MRSA were 100% susceptible to vancomycin and linezolid. rnIn the present study, cefoxitin diffusion method has given 100% sensitivity and specificity in concordance with MIC method. However, the oxacillin screen agar method showed 95.24% sensitivity and 96.55% specificity. As per our study and previous reports elsewhere on phenotypic detection of MRSA, cefoxitin is more potent inducer of the regulatory system and an accurate surrogate marker for the detection of MRSA in the routine susceptibility testing.

2013 ◽  
Vol 7 (1) ◽  
pp. 07-10 ◽  
Author(s):  
Durdana Chowdhury ◽  
Sanya Tahmina Jhora ◽  
Shika Paul ◽  
Tarek Mahbub Khan ◽  
Mili Rani Saha ◽  
...  

The study was designed to evaluate the efficacy of cefoxitin disc diffusion test to detect methicillin resistance in Staphylococcus aureus and compare it with oxacillin disc diffusion test and detection of mecA gene by PCR.  A total 116 S. aureus were isolated from clinical samples, collected from SSMC&MH, BIRDEM and NMC hospital, and was isolated by culture and identified by standard laboratory procedure. Antibiotic susceptibility testing was performed by oxacillin (1µg) and cefoxitin (30 µg) discs. PCR for amplification of mecA gene was performed as a gold standard method. Out of 116 isolates, 28 were PCR positive, 33 and 31 were oxacillin and cefoxitin resistant respectively. The sensitivity and specificity for the detection of MRSA was 100% and 94.31%inoxacillin disc diffusion test, and 96.42% and 95.45%in cefoxitin disc diffusion test respectively. Specificity is higher (95.45%) in cefoxitin disc diffusion test than oxacillin disc diffusion test in the detection of MRSA. Use of disc diffusion tests for both oxacillin and cefoxitin can help in more accurate prediction of methicillin resistance than single test, especially in centers which are not equipped to carry out more sophisticated tests for the detection of MRSA.DOI: http://dx.doi.org/10.3329/bjmm.v7i1.19314 Bangladesh J Med Microbiol 2013; 07(01): 7-10


2014 ◽  
Vol 7 (1) ◽  
pp. 1-4
Author(s):  
Durdana Chowdhury ◽  
Sanya Tahmina Jhora ◽  
Tarek Mahbub Khan ◽  
Sadia Afroz

The aim of this study was to evaluate the efficacy of MRSA Chrome agar to detect methicillin resistant Staphylococcus aureus (MRSA) and compare it with 1?g oxacillin disc diffusion tests and detection of mecA gene by PCR. A total 116 Staphylococcus aureus (S. aureus), isolated from various clinical samples, were obtained from three tertiary care hospitals of Dhaka city. S. aureus was identified by colony characters, Gram stain and standard biochemical procedures. MRSA was detected by susceptibility to 1?g oxacillin disc, growth of denim blue color colonies of S. aureus on the Brilliance MRSA Chrome agar at 24 and 48 hours of incubation. PCR was performed for amplification of mecA gene as a gold standard method. Out of 116 isolated S. aureus, 33 (28.44%) were MRSA by oxacillin disc diffusion test where mecA gene was detected in 28 strains. On MRSA Chrome agar, 29 (25.0%) S. aureus produced denim blue colonies at 24 hours, of which 28 isolates possessed mecA gene. At 48 hours incubation, an additional 4 isolates yielded denim blue colonies from which mecA gene could not be identified. All the strains of S. aureus that produced denim blue colonies at 24 and 48 hours were resistant to oxacillin. The sensitivity, specificity and accuracy of oxacillin disc diffusion test were 100%, 94.31% and 95.68% and Chrome agar at 24 hours were 100%, 98.86% and 99.13% respectively. Thus MRSA Chrome agar could be good choice in clinical microbiology laboratory for rapid and accurate identification of MRSA. DOI: http://dx.doi.org/10.3329/imcj.v7i1.17697 Ibrahim Med. Coll. J. 2013; 7(1): 1-4


Author(s):  
Kirti Hemwani ◽  
P. S. Nirwan ◽  
Preeti Shrivastava ◽  
Abhiraj Ramchandani

Background: Nonfermentative gram negative bacilli (NFGNB) frequently considered as commensals or contaminants but the pathogenic potential of nonfermenters has been proved beyond doubt. They are resistant to commonly used antimicrobials. Aim: This study was undertaken to identify the nonfermenters isolated from various clinical samples and to know their Antibiotic sensitivity pattern. Materials and Methods: The present study was carried out on 150 strains of Nonfermenters isolated from 1200 various non repetitive clinical samples received in Department of Microbiology, NIMS Jaipur. Nonfermenters were identified using a standard protocol and their antibiotic susceptibility testing was performed with the help of the modified Bauer disc diffusion method. Results: Out of 150 nonfermenters isolated, Pseudomonas aeruginosa was the most common isolate 134 (89.33%) followed by Acinetobacter baumannii 16 (10.67%). Among all clinical samples Pus and Wound Discharge yield maximum isolates of NFGNB i.e. 54 (36%) % followed by sputum (39.0%). Most sensitive drug against NFGNB was Polymyxin-B (100%) followed by Imipenem (86 %) and Amikacin (71.33 %). Conclusion: Nonfermenters have a great potential to survive in a hospital environment so implementation of antibiotic stewardship programs and strict infection control practices will be required to prevent or slow down their emergence and spread. Keywords:  Nonfermenters,  Polymyxin-B, Pseudomonas, Acinetobacter.


Author(s):  
Harsha Sreedharan ◽  
KB Asha Pai

Introduction: Methicillin-Resistant Staphylococcus aureus(MRSA) infection is a major global healthcare problem, the prevalence of which varies from 25-50% in India. It is known to cause Skin and Soft tissue Infections (SSI), endovascular infections, endocarditis, pneumonia, septic arthritis, osteomyelitis, and sepsis. Vancomycin is the drug of choice for treating severe MRSA infections. Ceftaroline, a fifth-generation cephalosporin has been approved by the United States Food and Drug Administration (US FDA) for treating acute bacterial SSI caused by susceptible micro-organisms including MRSA, Community acquired respiratory tract infection, MRSA bacteremia and endocarditis. Aim: To assess the susceptibility of clinical isolates of S. aureusto ceftaroline, in a Tertiary Care Hospital. Materials and Methods: This prospective study was conducted in the Department of Microbiology of a Tertiary Care Hospital over a period of two months from June 2019 to July 2019. S.aureus isolates from various clinical samples were screened for methicillin resistance by disc diffusion method using cefoxitin disc and ceftaroline susceptibility of these isolates was assessed by E-strip method. The isolates were classified as ceftaroline susceptible, Susceptibility Dose Dependent (SDD) and ceftaroline resistant respectively as per CLSI guidelines. A descriptive analysis of the data was done and the results were presented as frequencies and percentages. Results: All the S.aureus isolates were found to be susceptible to ceftaroline. Methicillin Sensitive Staphylococcus aureus(MSSA) isolates had lower Minimum Inhibitory Concentration (MIC) when compared to MRSA. The highest MIC among MRSA was 0.5 μg/mL. Conclusion: Ceftaroline can be considered as an effective alternative for treatment of infections caused by MRSA.


2012 ◽  
Vol 10 (2) ◽  
pp. 1-3 ◽  
Author(s):  
Raina Chaudhary ◽  
Khagendra Sijapati ◽  
Sunil Kumar Singh

Introduction: Enteric fever is the commonest public health problem in developing countries like Nepal. Multi Drug Resistant Salmonella isolates are in vitro susceptible to Quinolone but exhibited a higher Minimum Inhibitory Concentration in vivo. Such phenomenon can be demonstrated by simple disc diffusion test of Nalidixic Acid which shows resistance. This study is conducted to determine prevalence of Nalidixic Acid Resistant Salmonella with their anti biotic sensitivity pattern at Shree Birendra Hospital, Chauni, kathmandu. Method: Of total 3945 blood samples from the patients suspected to have enteric fever were collected during the period of January 2011 to August 2011. Then it was mixed with Brain Heart Infusion , further processed according to standard methodology and their anti microbial susceptibility was performed by Kirby-Bauer disc diffusion method. Results: From 3945 samples, 280 (7.09%) showed positi ve growth, 114 (40.7%) Salmonella enterica serotype Typhi and 166 (59.2%) Salmonella enterica serotype Paratyphi A. a total of 221 (78.92%) were Nalidixic Acid Resistant Salmonella, all these strains were sensitive to Ciprofloxcin and Ofloxacin in disc diffusion test. Conclusion: Study showed a higher frequency of Nalidixic Acid Resistant Salmonella among the patients. screening of Nalidixic Acid disc diffusion test must be done as routine work for determination of low level resistance of Quinolone so as to decide the drug for the treatment of enteric fever. DOI: http://dx.doi.org/10.3126/mjsbh.v10i2.6453 Medical Journal of Shree Birendra Hospital July-Dec 2011 10(2) 1-3


2020 ◽  
Vol 13 ◽  
pp. 117863372095207
Author(s):  
Kiran Duwadi ◽  
Sujan Khadka ◽  
Sanjib Adhikari ◽  
Sanjeep Sapkota ◽  
Pabitra Shrestha

Introduction: Patients with malignancies frequently develop infections as a result of surgical procedures and fungating wounds leading to pus formation. This cross-sectional study was conducted to explore the bacteriological spectra of infections of various cancer sites and their antibiotic sensitivity patterns among the patients visiting minor operation theatre (OT) of B.P. Koirala Memorial Cancer Hospital (BPKMCH), Chitwan, Nepal. Methods: Over a period of 3 months from September to November 2018, a total of 183 wound exudates and pus samples were collected and analyzed by standard microbiological procedures. Isolates were identified based on the colony characters, Gram staining and an array of biochemical tests. Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion technique according to criteria set by CLSI, 2016. Methicillin resistance in Staphylococcus aureus was tested with the help of cefoxitin using disc diffusion method. Results: Out of the 183 samples, 149 (81.4%) were culture positive. Among 13 different isolates identified, S. aureus (43.0%) was predominant followed by E. coli (14.0%). Higher incidence of bacteria was seen among the males (52.3%), in the age group 51 to 60 years (26.8%) and among the patients undergoing surgical intervention to deal with cancer (34.2%). The prevalence of wound infection was significantly affected by gender, age, and treatment regimen ( P < .01). Out of the total 68 S. aureus isolates, 38 (44.1%) were deemed as Methicillin-resistant Staphylococcus aureus (MRSA). Among the 158 isolates, 85 (53.8%) were multi-drug resistant (MDR). Cefepime was the most effective antibiotic for Gram positive isolates whereas both imipenem and meropenem were found to be equally more effective for Gram negative isolates. Conclusion: This study suggests that patients with malignancies harbor pathogenic bacteria; therefore, prudent use of antibiotics is essential to prevent the emergence of MDR pathogens.


2020 ◽  
Vol 2020 ◽  
pp. 1-5
Author(s):  
S. Gautam ◽  
N. R. Bhattarai ◽  
K. Rai ◽  
A. Poudyal ◽  
B. Khanal

Background. Carbapenem resistance among Gram-negative isolates caused by the production of the metallo-β-lactamase (MBL) enzyme is being increasingly reported worldwide. One of the newly emerged metallo-β-lactamases is New Delhi metallo-β-lactamase. Data regarding its occurrence in hospital setting and percentage prevalence among different Gram-negative bacterial isolates are lacking in our part. This study has been undertaken for determining the presence of the bla NDM-1 gene among the clinical isolates of imipenem-resistant Gram-negative bacteria in a tertiary care center in Dharan, Nepal. Methods. A total of 75 imipenem-resistant Gram-negative isolates were studied. These were screened for metallo-β-lactamase (MBL) production by phenotypic assays such as double-disc synergy test (DDST) and combined disc diffusion test (CDDT). PCR was performed for the molecular detection of gene NDM-1. Ten-disc method was performed to detect the presence of ESBL, AmpC, carbapenamase, and K1 β-lactamase production. Results. Using the molecular method, bla NDM-1 was detected in 36% of the isolates. Phenotypically, double-disc synergy test (DDST) and combined disc diffusion test (CDST) detected MBL production in 38.7% and 37.3% of the isolates, respectively. Ten-disc method detected ESBL in 26.6% of the isolates, but none of the isolates was found to be AmpC, carbapenamase, and K1 β-lactamase producers. Conclusion. A high percentage of the NDM-1 producer was noted among imipenem-resistant GNB. Apart from performing only antimicrobial sensitivity test, phenotypic and molecular screening should be employed to find out the actual number of metallo-β-lactamase producers and the existence of the resistance gene.


Author(s):  
Ebrahim Sande ◽  
Danstone Lilechi Baraza ◽  
Selline Ooko ◽  
Peter Kuloba Nyongesa

Aims: To determine the chemical composition and antibacterial activity of Kenyan Ganoderma lucidum. Study Design: Structural determination of the isolated compound was done using spectral evidences and in comparison with literature. The antibacterial properties of the compound was done using disc diffusion method. Place and Duration of Study: Department of Pure and Applied Chemistry, Masinde Muliro University of Science and Technology, between January and November, 2019. Methodology: Sequential extraction of dried samples of Kenyan G. lucidum were done using solvents hexane, ethyl acetate and methanol. Chromatographic separation of hexane extract of Ganoderma lucidum was done using spectroscopic data. The compound was assayed against Escherichia coli, Klebsiella pneumoniae, Methicillin–Resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Streptococcus pyogenes. Standard antibiotic namely; ampicillin was used as the control. Disc diffusion method was used and zones of inhibition, after respective incubation periods, were used to quantify antibacterial activity. Results: From hexane extract of Ganoderma lucidum, Ergosta-5, 7, 22-triene-3β, 14α – diol (22Z) was isolated. Ethylacetate and methanol extracts produced a mixture of complex compounds. Ergosta-5,7,22-triene-3β,14α-diol (22Z) exhibited significant activity against Methicillin-Resistance Staphylococcus aureus (MRSA) (p=0.022) and Streptococcus pyogenes (p = 0.05). The most sensitive microbe was Streptococcus pyogenes. Conclusion: One major compound, Ergosta-5, 7, 22-triene-3β, 14α – diol (22Z) was isolated, characterized and antibacterial activity determined.


Author(s):  
K. Sathyavathy ◽  
B. Kiran Madhusudhan

The aim of the study was to investigate the antimicrobial susceptibility pattern of Klebsiella species from different clinical samples at Sree Balaji Medical College and Hospital, India. Overall 189 samples out of 980 non repetitive clinical samples obtained from wound/pus, urine, sputum swab and blood by disc diffusion method and identified as Klebsiella and analysed. Out of total 189 Klebsiella isolates, 76 out of 155 K. pneumoniae (49%) were resistant and none out of 34 Klebsiella oxytoca (0%) showed resistance to cefotaxime and ceftazidime by disc diffusion method. Antimicrobial susceptibility testing of Klebsiella exhibited 100% resistance to Ampicillin. The present study highlights the need for the continued monitoring of antimicrobial susceptibility patterns of important bacterial pathogens, so that rational antibiotic policies can be formulated.


Sign in / Sign up

Export Citation Format

Share Document