scholarly journals Analysis of Antibiotics Susceptibility of Old and Fresh ATCC Strain of Staphylococcus aureus by Standard Agar Diffusion Technique

1970 ◽  
Vol 24 (2) ◽  
pp. 137-142
Author(s):  
Marufa Zerin Akhter ◽  
Ibrahim Khalil ◽  
Priyanath Roy ◽  
Mir Mohammad Ibna Masud

A comparative study of an old and fresh ATCC strain of Staphylococcus aureus was carried out to determine the mechanism of antibiotic resistance of the old one, which had been preserved in lyophilized condition. Five different antibiotics having five different modes of action were used. They included amoxicillin, azithromycin, neomycin, ciprofloxacin and polymixin B. Agar diffusion technique was followed to determine the antibiotic sensitivity. It was observed that the old strain showed the highest resistance against amoxicillin, whereas no remarkable changes in the sensitivity pattern were observed against polymixin B and neomycin. In case of azithromycin and ciprofloxacin, the old strain showed resistance up to some extent. From these results it was clearly evident that in the controlled preserved conditions, cell wall-mediated resistance was predominating, while the cell membrane- and 30S ribosome-mediated resistance were the least likely ones. The nucleic acid synthesis inhibitors and the 50S ribosomal protein synthesis inhibitor lied in between these two extremes showing variations up to some extent in the sensitivity pattern between the old and fresh ATCC strain of S. aureus. Keywords: Staphylococcus aureus, Antibiotic resistance mechanismDOI: http://dx.doi.org/10.3329/bjm.v24i2.1259 Bangladesh J Microbiol, Volume 24, Number 2, December 2007, pp 137-142

Author(s):  
T. Ramasamy ◽  
S. Keerthana ◽  
M.R. Srinivasan ◽  
D. Chandrasekar ◽  
K. Porteen ◽  
...  

Background: Antimicrobial resistance is one of the latest challenges facing the scientific community. Raising the drug resistance is caused mainly by indiscriminate usage of antibiotics in human and animal subjects and the spread of antibiotic resistance between the two has an emerging global threat. Hence, current study aimed to study the antimicrobial resistance pattern and molecular detection of antibiotic resistance genes in Staphylococcus aureus and Escherichia coli isolated from mastitis affected cows. Methods: Milk samples from mastitis affected cows were subjected to antibiotic sensitivity test and screened for presence of Staphylococcus aureus and Escherichia coli using differential growth media. Molecular characterization of Staphylococcus aureus and Escherichia coli was done with the help of PCR by amplification of ‘nuc’ and ‘uspA’ gene respectively. MICs of Penicillin and Tetracycline were determined using microdilution method. Result: Antibiotic sensitivity pattern for Penicillin G, Ampicillin, Amoxycillin, Cefotaxime, Ceftriaxone, Azithromycin, Ciprofloxacin, Gentamicin, Oxytetracycline, Tetracycline and Vancomycin were 74.19%, 100%, 93.50%, 61.29%, 29%, 35.48%, 9.70%, 9.70%, 70.96% and 70.96% respectively. More than 87.90% of the S. aureus and 50% of the E. coli isolated were resistant to â-lactam antibiotics while 75% of the E.coli and 65.70% of the S. aureus isolated were resistant to Tetracycline antibiotics. The MICs of Penicillin for S.aureus and E.coli are 26.88 µg/ml and 13.54 µg/ml respectively and the MICs of Tetracycline for S. aureus and E. coli are 243.75 µg/ml and 960.93 µg/ml respectively which is 8-9 folds higher than the standard MICs. From the present study, it can be inferred that bovine mastitis cases are highly resistant to antimicrobial drugs. Results further indicate that Staphylococcus aureus and Escherichia coli are both resistant to Penicillin and Tetracycline with very high MIC.


Microbiology ◽  
2014 ◽  
Vol 160 (10) ◽  
pp. 2157-2169 ◽  
Author(s):  
Sudarson Sundarrajan ◽  
Junjappa Raghupatil ◽  
Aradhana Vipra ◽  
Nagalakshmi Narasimhaswamy ◽  
Sanjeev Saravanan ◽  
...  

P128 is an anti-staphylococcal protein consisting of the Staphylococcus aureus phage-K-derived tail-associated muralytic enzyme (TAME) catalytic domain (Lys16) fused with the cell-wall-binding SH3b domain of lysostaphin. In order to understand the mechanism of action and emergence of resistance to P128, we isolated mutants of Staphylococcus spp., including meticillin-resistant Staphylococcus aureus (MRSA), resistant to P128. In addition to P128, the mutants also showed resistance to Lys16, the catalytic domain of P128. The mutants showed loss of fitness as shown by reduced rate of growth in vitro. One of the mutants tested was found to show reduced virulence in animal models of S. aureus septicaemia suggesting loss of fitness in vivo as well. Analysis of the antibiotic sensitivity pattern showed that the mutants derived from MRSA strains had become sensitive to meticillin and other β-lactams. Interestingly, the mutant cells were resistant to the lytic action of phage K, although the phage was able to adsorb to these cells. Sequencing of the femA gene of three P128-resistant mutants showed either a truncation or deletion in femA, suggesting that improper cross-bridge formation in S. aureus could be causing resistance to P128. Using glutathione S-transferase (GST) fusion peptides as substrates it was found that both P128 and Lys16 were capable of cleaving a pentaglycine sequence, suggesting that P128 might be killing S. aureus by cleaving the pentaglycine cross-bridge of peptidoglycan. Moreover, peptides corresponding to the reported cross-bridge of Staphylococcus haemolyticus (GGSGG, AGSGG), which were not cleaved by lysostaphin, were cleaved efficiently by P128. This was also reflected in high sensitivity of S. haemolyticus to P128. This showed that in spite of sharing a common mechanism of action with lysostaphin, P128 has unique properties, which allow it to act on certain lysostaphin-resistant Staphylococcus strains.


2021 ◽  
Vol 8 (02) ◽  
pp. 80-84
Author(s):  
Smitha B ◽  
Swapna U.P ◽  
Salilkumar K

BACKGROUND Active mucosal chronic otitis media (COM) is a disease of the middle ear cleft associated with inflammation and production of pus. The incidence is high in developing countries. It affects all age groups and both genders. If not properly treated, it can lead to complications. The bacterial isolates and their sensitivity pattern vary from place to place and also over time. Early identification of the microorganisms and their antibiotic sensitivity patterns helps in proper selection of antibiotics and quick recovery in COM patients. METHODS Fifty patients with active mucosal COM were selected for the study. The study was conducted over a period of one year. Ear swab from the deep external auditory canal was collected under strict aseptic precautions from these patients before starting antibiotic treatment. Microorganisms were identified by gram staining, growth on different agar plates, and various biochemical tests. Antibiotic sensitivity was done by the Kirby-Bauer method. RESULTS Majority of the patients were in the age group of 21 - 40 years (42 %) with female preponderance (62 %). All patients had a central perforation in the tympanic membrane (100 %). Bacterial growth was seen in 44 samples (88 %). Two samples (4 %) showed fungal growth. Four samples (8 %) showed no growth even after 48 hours of incubation. Single bacterium was isolated in 41 cases (82 %) whereas 3 samples (6 %) showed more than one bacterial growth. The predominant bacteria were Pseudomonas aeruginosa (50 %) followed by Staphylococcus aureus. The other isolates were coagulase negative staphylococci, enterococci, enterobacter, acinetobacter, and E coli. Pseudomonas showed maximum sensitivity to amikacin, imipenem and piperacillin / tazobactam (100 %). The most effective antibiotics for staphylococcus was vancomycin and linezolid. CONCLUSIONS The most common bacteria isolated in active mucosal COM were pseudomonas followed by Staphylococcus aureus. The most effective antibiotics for pseudomonas was amikacin, imipenem and piperacillin / tazobactam. Staphylococcus showed maximum sensitivity to vancomycin and linezolid. KEYWORDS Chronic Otitis Media (COM), Active Mucosal, Ear Swab, Bacteriology, Sensitivity


Author(s):  
Rashmi Ramashesh ◽  
Samira Abdul Wajid ◽  
Smitha Chandra

<p class="abstract"><strong>Background:</strong> Chronic suppurative otitis media (CSOM) is an ever growing concern of preventable hearing loss and is a major health concern especially in tropical countries. Lack of cleanliness, overcrowding, poverty, malnutrition and medical ignorance are few of the contributing factors. The microbiological flora is constantly changing due to indiscriminate use of antibiotics with rapid change in the antibiotic sensitivity patterns. Hence, this study was undertaken to determine the epidemiological profile, bacteriological profile and the antibiotic sensitivity pattern which would help in establishing a protocol in management of CSOM patients in the hospital.</p><p class="abstract"><strong>Methods:</strong> A total of 100 patients of CSOM attending the ENT Outpatient Department of The Oxford medical College, Hospital and Research Centre were included in the study. The samples were immediately sent to the Microbiology laboratory for further processing according to standard procedure.  </p><p class="abstract"><strong>Results:</strong> Out of 100 cases, 74 were active mucosal type and 26 were active squamous, with Pseudomonas species (33.6%) being the predominant organism. <em>Staphylococcus aureus</em> was the next common organism with MSSA (16.3%) and MRSA (12.5%), CONS were 6.7%. Among the 28 gram-negative bacilli, <em>Klebsiella pneumoniae</em> (7.7%), was followed by <em>Escherichia coli</em> (5.7%), and <em>Proteus mirabilis</em> (4.8%).</p><p class="abstract"><strong>Conclusions:</strong> Pseudomonas species and <em>Staphylococcus aureus</em> are the commonest organisms of CSOM. Ciprofloxacin can be used as a topical agent for treating gram-negative bacilli. Among systemic antibiotics- Linezolid, Amikacin and Imepenam remains the drug of choice.</p><p><br /><br /></p>


2020 ◽  
Vol 11 (1) ◽  
pp. 974-980
Author(s):  
Anand Vijayakumar PR ◽  
Lalramengmawii ◽  
Lalduhawmi TC ◽  
Manisha S ◽  
Shekhar S Deshpande

Antibiotics resistance is an emerging problem in the management for infectious diseases. Patients are many a time prescribed with antibiotics without knowing that particular antibiotic sensitivity pattern with respect to the infectious microorganism. This study aims to detect the type of microbes causing certain infections in the hospital and also to detect the sensitivity pattern of the antibiotics to these microbes. We conducted a prospective study for six months on the neonates who were admitted in NICU. The blood samples were collected from these neonates before the administration of antibiotics. The swab samples were also collected from various places of this hospital to detect the types of microorganisms present in the hospital and to study the sensitivity of the antibiotics toward these microbes. The antibiotics used in this study were Gentamicin, Ampicillin, Cefotaxime, Amikacin, Piperacillin, Meropenam, and Vancomycin. Staphylococcus aureus and Streptococcus pneumoniae were found to be the most common pathogens implicated in neonate's infection. All the organisms showed absolute sensitivity mostly to Ampicillin, Gentamicin, and Piperacillin and resistant to Cefotaxime, Amikacin, and Vancomycin. Staphylococcus aureus, Streptococcus pneumoniae, Hemophilus infleunzae, Kleibseilla pneumoniae, Escherichia coli were the most common microorganism found in the swab samples collected from the hospital. Most of these microorganisms shows sensitivity towards Ampicillin, Gentamicin, and Meropenam but were resistance to Cefotaxime, Amikacin, and Vancomycin. A routine bacterial surveillance of prevalent organisms and the study of the sensitivity patterns of the pathogens responsible for neonatal infection should be made an essential component for neonatal care. This information from many parts of the country will be important in policymaking on antimicrobial use not only locally but also internationally.


2020 ◽  
Vol 16 (2) ◽  
pp. 73
Author(s):  
Nurhafizah Rafiani ◽  
Renny Aditya ◽  
Noor Muthmainah

Abstract: A cesarean delivery increases the risk of wound infection it should be prevented by using antibiotics. This study was to determine the pattern of bacterial sensitivity in surgical wounds of cesarean section patients for selected antibiotics, i.e ceftriaxone, cefixime, sulbactam ampicillin, ciprofloxacin, clindamycin and gentamicin.This observational study was conducted at the Ulin Public Hospital in Banjarmasin from July to September 2019. Using a cross sectional approach Samples of bacteria were identidied from 36 that were pusposively sampled, i.e., Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli. Antibiotic sensitivity test showed that Staphylococcus aureus was sensitive against gentamicin (100%),whereas Staphylococcus epidermidis and Escherichia coli. Were intermediately sensitive towards gentamicin (62.5%) and ceftriaxone (80%) Keywords: Antibiotic susceptibility, caesarean section, surgical wound


2017 ◽  
Vol 7 (2) ◽  
pp. 101-105
Author(s):  
Jamal Uddin Ahmed ◽  
Mohammad Delwar Hossain ◽  
Muhammad Abdur Rahim ◽  
Farhana Afroz ◽  
AKM Musa

Background: Diabetes mellitus (DM) is an immunosuppressive condition and uncontrolled diabetes is associated with increased susceptibility to various infections like pneumonia. Community acquired pneumonia (CAP) in diabetic patients is often caused by more virulent or atypical organisms and associated with increased resistance to conventional antibiotics. The aims of this study were to identify the bacterial etiology of CAP in patients with DM and to see their antibiotic sensitivity pattern.Methods: This was a cross-sectional, observational study conducted in the Department of Internal Medicine & Pulmonology of BIRDEM General Hospital, Dhaka, Bangladesh, from January 2013 to December 2015. A total of 120 hospitalized diabetic patients diagnosed with CAP and with a positive sputum culture growth of any bacteria were included in the study.Results: Majority (67%) of the patients were male. Mean age of the patients was - 55.69 ±10.5 years. Mean duration of diabetes was - 7.35 ±1.3 years. Mean HbA1c was - 8.6 ±1.89%. Sputum for culture showed that out of 120 (100%) patients, Klebsiella pneumoniae was detected in 53 (44.2%) patients, Staphylococcus aureus in 18 (15.0%), Pseudomonas species in 16 (13.3%) patients, Acinetobacter in 10 (8.3%), Escherichia coli in 9 (7.5%) patients and 14 (11.7%) patients had growth of other organisms. Sensitivity pattern of different bacterial growth in sputum to commonly used antibiotics like ceftriaxone, ciprofloxacin, amikacin and imipenem were as follows – Klebsiella (19%, 47%, 74%, 96% respectively), Staph aureus (11%, 33%, 78%, 67% respectively), Pseudomonas (19%, 75%, 81%, 88% respectively), Acinetobacter (0%, 0%, 20%, 50% respectively), E. coli (22%, 22%, 100%, 100% respectively). All (100%) of the Pseudomonas and Acinetobacter were sensitive to colistin. Most of the growth of all the bacteria (Klebsiella 94%, Staphylococcus 78%, Pseudomonas 81%, Acinetobacter 100%, E. coli 100%) occurred in patients with poor glycemic control (HbA1c ? 7.0%).Conclusion: This study results suggest that CAP in diabetic patients are more frequently due to Klebsiella pneumoniae, Staphylococcus aureus and Pseudomonas species and mostly they are less sensitive to commonly used antibiotics like ceftriaxone and ciprofloxacin. So, whenever possible, treatment of CAP should be guided by sputum culture and sensitivity test and for empirical treatment of CAP in diabetic patients, alternative antibiotics like imipenem and amikacin should be considered.Birdem Med J 2017; 7(2): 101-105


2018 ◽  
Vol 09 (01) ◽  
Author(s):  
Okonkwo EC ◽  
Orji JO ◽  
Aondoackaa AD ◽  
Ugbo EN ◽  
Moses IB ◽  
...  

2017 ◽  
Vol 8 (1) ◽  
pp. 174-177
Author(s):  
Rowshan Jahan Akhter ◽  
Md Mahbubul Hoque ◽  
BH Nazma Yasmeen ◽  
MAK Azad Chowdhury

Introduction : Neonatal sepsis remains an important cause of neonatal morbidity and mortality in NICU setup and a major challenge for the neonatologists. The prevalent organisms and their antibiotic resistance patterns evolve with time and with the usage of antimicrobials.Aims and Objectives : To analyze the bacteriological profile and antibiotic resistance patterns of proven neonatal sepsis cases in Dhaka Shishu Hospital.Materials and Methods : The study was Prospective observational study. All the clinically suspected cases of Neonatal Sepsis admitted to the Neonatal word from January 2015 to December 2015 were included in the study. Clinically suspected cases of neonatal sepsis further evaluated with blood cultures and antibiotic susceptibility testing using the Kirby Bauer disc diffusion method. Data was collected for the following variables: Demographic profile, haematological profile, blood culture result and antibiotic sensitivity patterns.Results : Total 96 cases clinically suspected neonatal sepsis were included in the study. Among them 29 cases (30.21%) was culture positive septicemia. Klebsiella pneumoniae was the most common isolate accounting for 31.03% cases followed by Escherichia coli 27.59%. In Klebsiella infection most common sensitivity were Imipenum and Ciprofloxacin which were 77.78 and 33.33% respectively. In E.coli common sensitive drugs were Imipenum and Amikacin. In serratia common sensitive drugs were Imipenum, Netlmicin and Ciprofloxacin.Conclusion : K. pneumoniae was the most common pathogen. Most common sensitivity was Imipenum, Amikacin, Ciprofloxacin, Gentamicin, Netlmicin, and Ceftazidime,.Northern International Medical College Journal Vol.8(1) July 2016: 174-177


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