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Aims: Infections due to metallo-β-lactamase (MBL) producing Gram negative rods are a cause of high mortality and morbidity. Early detection by an economical and accurate method may improve patient outcome. This study was aimed to evaluate the diagnostic accuracy of combined disc method for MBL detection by comparing it with MBL-Etest.Methodology and Results: This cross-sectional, validation study was carried out in the Department of Microbiology, Army Medical College, National University of Sciences and Technology, Rawalpindi, over a period of six months. A total of 52 non-duplicate Gram-negative rods isolated from the routine clinical specimens and found resistant to meropenem/imipenem on Kirby Bauer Disc Diffusion method were subjected to two tests for metallo-β-lactamase detection. One was combined Disc test using imipenem with Ethylene Diamine Tetraacetic Acid (EDTA), where a strain showing an increase in zone of inhibition of combined disc of ≥ 7 mm as compared to imipenem alone, was considered as MBL producer and the other one was MBL-Etest for which results were interpreted as per manufacturer’s guidelines. Combined disc method for MBL detection was found to have a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 97.5%, 100%, 100%, 92% and 98%.Conclusion, Significance and Impact of study: Combined disc method is an economical and reliable method for metallo-β-lactamase detection which can be used routinely in any laboratory.

Microorganisms adhere to non-living material or living tissue, and form biofilms made up of extracellular polymers/slime. Biofilm-associated microorganisms behave differently from free-floating bacteria with respect to growth rates and ability to resist antimicrobial treatments and therefore pose a public health problem. The objective of this study is to detect the prevalence of biofilm producers among Gram positive and Gram negative bacteria isolated from clinical specimens, and to study their antimicrobial susceptibility pattern. The study was carried out from October 2009 to March 2010, at the Department of Microbiology, Army Medical College/ National University of Sciences and Technology (NUST), Rawalpindi, Pakistan. Clinical specimens were received from various wards of a tertiary care hospital. These were dealt by standard microbiological procedures. Gram positive and Gram negative bacteria isolated were subjected to biofilm detection by congo red agar method (CRA). Antimicrobial susceptibility testing of those isolates, which showed positive results (slime production), was done according to the Kirby-Bauer disc diffusion technique. A total of 150 isolates were tested for the production of biofilm/slime. Among them, 81 isolates showed positive results. From these 81, 51 were Gram positive and 30 were Gram negative. All the 81(54%) slime producers showed reduced susceptibility to majority of antibiotics. Bacterial biofilms are an important virulence factor associated with chronic nosocomial infection. Detection of biofilm forming organisms can help in appropriate antibiotic choice.

ABSTRACT Introduction: With the abundant use of the internet, patients undergoing or interested in orthodontic treatment try to use it to obtain information on pain during treatment. However, YouTube™ is unregulated and may potentially contain inaccurate information. Objectives: Thus, this study aimed to evaluate the scientific quality of the videos on YouTube™ related to orthodontic pain management. Methods: A total of 62 videos related to orthodontic pain management were included in the study. All videos were evaluated by two experienced orthodontists. The video uploader, content, length, upload date, time since upload, number of views, comments, likes, dislikes, Interaction index, and Viewing rate of the videos were recorded and evaluated. The videos were scored using the Quality Criteria for Consumer Health Information (DISCERN), Global Quality Scale (GQS), and Audio-Visual Quality (AVQ), and divided into two groups: Doctors and Non-doctors. Results: The mean DISCERN score was 2.56 ± 0.91, the GQS score was 2.56 ± 1.06, and AVQ was 2.48 ± 0.68. A statistically significant difference was found in DISCERN score of videos uploaded by Doctors compared to Non-doctors, but no statistically significant difference was found in GQS and AVQ scores between both groups (p> 0.05). Conclusions: The videos uploaded by Doctors were better in terms of quality and reliability, as compared to Non-doctors; and the AVQ of the videos uploaded by both groups was adequate. Despite that, both groups did not serve as a good source of information. YouTube™ cannot be considered a reliable source of information in terms of quality and reliability on videos related to orthodontic pain management.

Background: The impact of COVID-19 pandemic over nonessential health services has been massive. We initiated influenza-like illness (ILI) screening for resumption of outpatient services at a tertiary care center and this study attempted to gauge its efficacy in effectively pruning out COVID-19. Methods: We included all the patients who had visited for an outpatient department (OPD) appointment during the study period. Patient's details and ILI symptoms were noted. Patients were then followed up telephonically after 2 weeks. The telephonic follow-up was to ensure RT-PCR status and complaints of any newly developed ILI post-OPD visit (within the last 14 days). Results: Out of the 957 patients who were enrolled, 929 patients were successfully followed up telephonically after 14 days. Only 13 who were screened out as “possible ILI,” were either RT-PCR negative or did not follow-up with a confirmatory test. The telephonic follow-up to ensure RT-PCR status and complaints of any newly developed ILI post-OPD visit (within the last 14 days) was noted in the rest of the patients. Only one participant out of 957 screened, tested positive for COVID-19. Conclusion: The period in which the study was held, the national positivity rate was low (around 3%). Therefore, in a resource-limited country such as India, it is astute to restart the OPD services in the preexisting setup using basic precautions and a verbal questionnaire during the slope of the pandemic.

Background and Objectives: This study was designed to determine the in vitro efficacy of mecillinam against extended spectrum beta lactamse producing Enterobacterales., Materials and Methods: After proper permission from Ethical Review Committee of the Institute, all samples yielding growth of ESBL producing Enterobacterales were part of the study and were processed according to routine microbiological procedures. Routine antibiotic sensitivity testing was done on Muller Hinton Agar by Modified Kirby Bauer Method. All Gram negative isolates were subjected to concomitant detection of ESBL production by double disc synergy method. All ESBL producers were then subjected to the mecillinam Minimum Inhibitory Concentration (MIC) determination by E test. The results were interpreted as per CLSI Guidelines., Results: A total of 120 ESBL producing Enterobacterales isolates were included in the study. The mean age of patients with ESBL infection was 45 ± 18.7 years. There were 44% male and 55% female patients. Majority of the ESBL producing Enterobacterales were isolated from urine samples (56%), followed by pus. Among the isolated organisms, Escherichia coli (45%) was the most frequently isolated organism followed by Klebsiella spp. (22%). Overall 83% of the isolates turned out to be sensitive to mecillinam. MIC50 of mecillinam against ESBL producing Gram negative rods (GNR) turned out to be 1 ug/ml and MIC90 turned out to be 2 ug/ml., Conclusion: Mecillinam shows good in vitro efficacy against ESBL producing Enterobacterales in our study. Further studies with more sample size and from diverse areas across the country should be done to evaluate its efficacy., (Copyright © 2022 The Authors. Published by Tehran University of Medical Sciences.)

The novel use of ionic liquid as a solvent for biodegradable and natural organic biomaterials has increasingly sparked interest in the biomedical field. As compared to more volatile traditional solvents that rapidly degrade the protein molecular weight, the capability of polysaccharides and proteins to dissolve seamlessly in ionic liquid and form fine and tunable biomaterials after regeneration is the key interest of this study. Here, a blended system consisting of Bombyx Mori silk fibroin protein and a cellulose derivative, cellulose acetate (CA), in the ionic liquid 1-ethyl-3-methylimidazolium acetate (EMIMAc) was regenerated and underwent characterization to understand the structure and physical properties of the films. The change in the morphology of the biocomposites (by scanning electron microscope, SEM) and their secondary structure analysis (by Fourier-transform infrared spectroscopy, FTIR) showed that the samples underwent a wavering conformational change on a microscopic level, resulting in strong interactions and changes in their crystalline structures such as the CA crystalline and silk beta-pleated sheets once the different ratios were applied. Differential scanning calorimetry (DSC) results demonstrated that strong molecular interactions were generated between CA and silk chains, providing the blended films lower glass transitions than those of the pure silk or cellulose acetate. All films that were blended had higher thermal stability than the pure cellulose acetate sample but presented gradual changes amongst the changing of ratios, as demonstrated by thermogravimetric analysis (TGA). This study provides the basis for the comprehension of the protein-polysaccharide composites for various biomedical applications.

Objective: To determine frequency of Endogenous Methicillin Resistant Staphylococcus aureus (MRSA) in pre-operative patients and its frequency in Surgical Site Infections (SSIs) post operatively., Methods: It was a descriptive cross sectional conducted at Department of Microbiology, Fauji Foundation Hospital Rawalpindi (FFH), Pakistan. Samples were collected from 1st November-31st May 2018. Total 75 samples were collected during the period. Consecutive non-probability sampling technique was utilized. Specimens were collected from nose, axilla and groin of preoperative patients. Methicillin Resistant Staphylococcus aureus was identified if only isolated from these sites. Patients were followed till his/her discharge from the hospital and if they developed infection post operatively, pus specimen from infected site was also collected and identified., Results: Out of 75 specimen preoperatively, 11(14.7%) were identified as endogenous MRSA. From these, 33(44%) developed Surgical site infections (SSIs), among them 19(57%) were MRSA (09 endogenous, 10 exogenous), 7(21.2%) were Escherichia coli, 3(9.1%) were Klebsiella pneumoniae, 3(9.1%) were Enterococcus faecalis and 1(3%) was Methicillin Sensitive Staphylococcus aureus., Conclusions: The results of this study determined that Endogenous Methicillin Resistant Staphylococcus aureus (MRSA) could be isolated from patients going for surgery if microbiological screening was done at the time of admission. This could prevent patients from Surgical Site Infection Post operatively by these endogenous MRSA. This search and wipe out strategy is able to curtail the events of outbreak, reduce hospital stay and decrease budget of the hospital by providing guidance in choice of empirical therapy for infection.

Salinity is one of the major threats faced by the modern agriculture today. It causes multidimensional effects on plants. These effects depend upon the plant growth stage, intensity, and duration of the stress. All these lead to stunted growth and reduced yield, ultimately inducing economic loss to the farming community in particular and to the country in general. The soil conditions of agricultural land are deteriorating at an alarming rate. Plants assess the stress conditions, transmit the specific stress signals, and then initiate the response against that stress. A more complete understanding of plant response mechanisms and their practical incorporation in crop improvement is an essential step towards achieving the goal of sustainable agricultural development. Literature survey shows that investigations of plant stresses response mechanism are the focus area of research for plant scientists. Although these efforts lead to reveal different plant response mechanisms against salt stress, yet many questions still need to be answered to get a clear picture of plant strategy to cope with salt stress. Moreover, these studies have indicated the presence of a complicated network of different integrated pathways. In order to work in a progressive way, a review of current knowledge is critical. Therefore, this review aims to provide an overview of our understanding of plant response to salt stress and to indicate some important yet unexplored dynamics to improve our knowledge that could ultimately lead towards crop improvement.

Stenotrophomonas maltophiliais an emerging cause of nosocomial infections. We report an outbreak of XDR-Stenotrophomonas maltophilia infection from burn unit of a tertiary care hospital in July 2016. The strain isolated was resistant to all antimicrobials tested but colistin. Outbreak investigation was carried out which subsided after timely intervention. Patients were treated adequately by Colistin.

Background: Extended Spectrum β-lactamases (ESBLs) are emerging as common nosocomial pathogens and important cause of mortality and morbidity, if not treated properly. The need of the hour is to find effective treatment options for dealing with ESBL producing organisms. This study was aimed to evaluate in vitro susceptibility pattern of extended spectrum β-lactamase producers against tetracyclines., Methods: This descriptive cross-sectional study was carried out in the department of Microbiology, Army Medical College, Rawalpindi, National University of Sciences and Technology over a period of 6 months. Seventy eight non-duplicate isolates were included in the study. ESBL detection was done using Jarlier et al method. In vitro susceptibility of tetracyclines like tetracycline, doxycycline, minocycline and tigecycline was then tested using Modified Kirby Bauer disc diffusion method. The zones of inhibition were measured after completion of incubation period and interpreted as per CLSI and FDA guidelines., Results: Approximately 56.4% of the isolates were Escherichia coli, 28.2% were Klebsiella pneumoniae, 10.26% were Enterobacter species, and 2.6% were each Klebsiella oxytoca and Acinetobacter species. ESBLs were found to be most sensitive to tigecycline, intermediate in susceptibility to minocycline while least sensitive to doxycycline and tetracycline., Conclusion: Among tetracyclines, tigecycline has best in vitro susceptibility against ESBL producing Gram negative rods.

A study was planned to explore and evaluate the role of senior peers in the learning process of their juniors during a Research Methodology workshop, and to assess educational advantages for seniors in leading roles. Twenty medical students participated with 15 juniors (1st to 3rd year) and 5 seniors (final/fourth year) divided into 5 groups with one senior student each at Foundation University Medical College, Islamabad, Pakistan. The seniors supervised and engaged the groups to develop research questions, formulate objectives, review literature, outline study designs, develop study tools/questionnaire and finally shape their projects in synopsis. Overall advantages to both juniors and seniors through this peer-assisted learning model were assessed by feedback proformas with open and closed-ended questions. Senior peers' facilitation was effective in the learning process of junior peers. Senior peers also gained academic benefit by exercising their leadership qualities through teaching and maintaining group dynamics.

Objective: To compare the in vitro efficacy of meropenem, colistin and tigecycline against extended spectrum Betalactamase producing Gram negative bacilli by minimal inhibitory concentration., Study Design: Cross-sectional descriptive study., Place and Duration of Study: Department of Microbiology, Army Medical College, National University of Sciences and Technology, Rawalpindi, from June to December 2010., Methodology: Routine clinical specimens were subjected to standard microbiological procedures and the isolates were identified to species level. Extended spectrum β-lactamase producing Gram negative bacilli were detected by Jarlier disc synergy method and confirmed by ceftazidime and ceftazidime-clavulanate Etest. Minimum Inhibitory Concentration (MIC(90)) of meropenem, colistin and tigecycline was determined by Etest (AB BIOMERIUX) and the results were interpreted according to the manufacturer's instructions and Clinical and Laboratory Standards Institute guidelines and Food and Drug Authority recommendations. Results were analyzed by using Statistical Package for the Social Sciences version 20., Results: A total of 52 non-duplicate extended spectrum Beta-lactamase-producing Gram negative bacilli were included in the study. The MIC(90) of tigecycline (0.75 µg/ml) was lowest as compared to the meropenem (2 µg/ml) and colistin (3 µg/ml)., Conclusion: Tigecycline is superior in efficacy against the extended spectrum Beta-lactamase producing Gram negative bacilli as compared to colistin and meropenem.

Background: Methicillin resistant coagulase-negative Staphylococci are resistant organisms causing infections associated with high morbidity and mortality. Methicillin resistant Staphylococcus epidermidis (MRSE), is especially important with respect to admitted patients with indwelling catheters and other installed invasive devices where these organisms are known to be found. As a result, such lifesaving measures may prove fatal from subsequent infection and sepsis by these pathogens. Therefore, to limit such conditions in patients, the spread of MRSE and related organisms in the hospitals have to be effectively controlled., Objectives: This study was carried out to determine the frequency of methicillin resistant organisms among all isolated coagulase negative Staphylococci (CoNS) and to find effective antibiotics against these microorganisms., Patients and Methods: All samples sent to the lab were routinely processed according to standard microbiological procedures and the cultures yielding growth of CoNS were selected for the study. All samples containing CoNS collected over a 2 year-period, were included irrespective of patients' age and gender. The antibiogram of the organisms was recorded according to CLSI guidelines and the ratio of methicillin resistant organisms determined., Results: From a total of 299 isolated coagulase negative Staphylococci (CoNS), 40.1% were methicillin resistant. A high proportion of these organisms (more than 50%) were resistant to cephalosporins, aminoglycosides and quinolones while only a small number were found to show resistance to linezolid, minocycline, chloramphenicol and rifampicin. There were no resistant organisms against vancomycin., Conclusions: A considerable amount of methicillin resistant organisms found among CoNS in our region. The above stated antibiotics would prove effective in limiting these infections. Clinicians should keep these facts in mind while treating their patients.

Objective: To compare the sensitivity and specificity of different phenotypic methods for detection of Amp C betalactamase producing bacteria., Study Design: Analytical study., Place and Duration of Study: Department of Microbiology, Army Medical College / National University of Sciences and Technology (NUST), Islamabad, Pakistan, from June 2010 to December 2010., Methodology: A total of 150 clinical isolates were screened for presence of Amp C beta-lactamase by using the cefoxitin disc. The confirmatory methods evaluated were inhibitor based assay (boronic acid), Amp C disc test and Amp C Etest. Three dimensional enzyme extract assay was used as the reference method for determining the sensitivity and specificity., Results: Among the total isolates tested, 62.8% bacteria showed the presence of Amp C beta-lactamase by standard three dimensional enzyme extract assay. Among the three methods compared, boronic acid disk test found out to be highly sensitive (88%) and specific (92%) for the detection of Amp C beta-lactamase producing bacteria., Conclusion: Detection of Amp C production is crucial in order to establish the antibiotic therapy and to attain the favourable clinical outcomes. Implementation of simple tests like boronic acid disk tests in the laboratories will help to alleviate the spread of Amp C beta-lactamase harboring organisms.

Multi-drug resistant bacteria are an important cause of mortality and morbidity. In the management of various infections, timely detection and appropriate treatment, in accordance with the culture and sensitivity reports can help improve the treatment outcome. Colistin is a bactericidal antibiotic which is emerging as a reliable solution for treating infections with multi-drug resistant Gram negative bacilli. The aim of this study was to find out the in-vitro efficacy of colistin against multidrug resistant Pseudomonas aeruginosa isolates by minimum inhibitory concentration. This cross sectional, descriptive study was conducted in the Department of Microbiology, Army Medical College, National University of Sciences and Technology, Islamabad from February 2010 to January 2011. Antimicrobial sensitivity testing was done on Pseudomonas aeruginosa isolated from routine clinical specimens received and the strains which appeared resistant to at least one antimicrobial agent in three or more anti-pseudomonal antimicrobial categories were subjected to the Colistin Etest. The MIC endpoint of colistin was read, as per manufacturers instructions (AB Biodisk, Solna, Sweden). The isolates showing MIC of 2μg/ml or less were considered sensitive, those with 4-6μg/ml as intermediate and >μg/ml as resistant. MIC(50) and MIC(90) of colistin against MDR Pseudomonas aeruginosa was determined. A total of 52 MDR Pseudomonas aeruginosa strains were isolated during the period of the study. The highest percentage was isolated from urine (36%) followed by respiratory tract infections (18%) and pus specimens (20%). The highest percentage of these isolates was found to be susceptible to colistin followed by piperacillin-tazobactam and cefoperazone-sulbactam. A total of 36(69%) isolates were sensitive, 10(20%) were intermediate and 6(11%) were resistant to colistin by Kirby Bauer disc diffusion method. MIC(50) was found to be 1.0μg/ml while MIC(90) was 3.0μg/ml. Colistin is a reliable solution in cases of infections with MDR, XDR or PDR Pseudomonas aeruginosa.

Objective: To find out the frequency and susceptibility pattern of multi-drug resistant (MDR) Pseudomonas aeruginosa in clinical specimens., Study Design: Cross-sectional observational study., Place and Duration of Study: Department of Microbiology, Army Medical College, National University of Sciences and Technology (NUST), Rawalpindi, from January to September 2010., Methodology: Routine clinical specimens were subjected to standard microbiological procedures and the isolates were identified to the species level. The antibiotics susceptibility was determined by Kirby Bauer Disc diffusion method and the results were interpreted according to the Clinical and Laboratory Standards Institute (CLSI) guidelines., Results: The frequency of MDR Pseudomonas aeruginosa among all the Pseudomonas aeruginosa strains isolated was found to be 22.7%. These isolates were most sensitive to Colistin followed by Piperacillin-Tazobactam and Cefoperazone-Sulbactum., Conclusion: Increasing fequency of infections due to MDR Pseudomonas aeruginosa is an emerging threat in our set up which an be prevented by prescribing antibiotics judiciously and by adopting proper disinfection measures.

Background: Microorganisms growing in a biofilm are associated with chronic and recurrent human infections and are highly resistant to antimicrobial agents. There are various methods to detect biofilm production like Tissue Culture Plate (TCP), Tube method (TM), Congo Red Agar method (CRA), bioluminescent assay, piezoelectric sensors, and fluorescent microscopic examination., Objective: This study was conducted to compare three methods for the detection of biofilms., Method: The study was carried out at the Department of Microbiology, Army Medical College, National University of Sciences and Technology, Pakistan, from January 2010 to June 2010. A total of 110 clinical isolates were subjected to biofilm detection methods. Isolates were identified by standard microbiological procedures. Biofilm detection was tested by TCP, TM and CRA. Antibiotic susceptibility test of biofilm producing bacteria was performed by using the Kirby-Bauer disc diffusion technique according to CLSI guidelines., Results: The TCP method was considered to be superior to TM and CRA. From the total of 110 clinical isolates, TCP method detected 22.7% as high, 41% moderate and 36.3% as weak or non-biofilm producers. We have observed higher antibiotic resistance in biofilm producing bacteria than non-biofilm producers., Conclusion: We can conclude from our study that the TCP method is a more quantitative and reliable method for the detection of biofilm forming microorganisms as compared to TM and CRA methods, and it can be recommended as a general screening method for detection of biofilm producing bacteria in laboratories.

Background and Objectives: Typhoid is a major health problem faced by the developing countries like Pakistan. More than 20 million cases are reported annually worldwide. Currently fluoroquinolones are the drugs of choice to treat typhoid fever. In vivo resistance to fluoroquinolones leading to therapeutic failure is developing rapidly and is becoming a major concern for the clinicians. The objective of this study was to determine the sensitivity pattern of Nalidixic acid over the last four years, Material and Methods: A descriptive cross sectional study was carried out at the Microbiology Department of the Army Medical College, National University of Sciences and Technology, Rawalpindi from January 2006 to December 2009. All the isolates were dealt with standard microbiological procedures. The antimicrobial sensitivity of Nalidixic acid and Ciprofloxacin was determined using Kirby-Bauer disc diffusion method as per the guidelines of Clinical and Laboratory Standard Institute (CLSI)., Results: Out of 240 isolates, 111 were Salmonella typhi and 129 were Salmonella paratyphi A. The resistance of the typhoidal Salmonella to Nalidixic acid has reached significant levels and it seems only a matter of time when hundred percent resistance will be encountered. All isolates were sensitive to Ciprofloxacin on disc diffusion method., Conclusion: Resistance to Nalidixic acid predicting therapeutic failure with fluoroquinolones is on a steady rise.

Objectives: To compare the in vitro activities of vancomycin and linezolid against methicillin resistant Staphyloccus aureus in our set up to help in formulating a better empirical treatment and reduce the emergence of vancomycin resistant Staphylococcus aureus., Methods: The study was conducted over a period of 6 months (1st July 2009-31st Dec 2009). Fifty Methicillin resistant Staphylococcus aureus isolated from the clinical isolates of Military Hospital Rawalpindi were subjected to the determination of Minimum inhibitory concentrations of linezolid and vancomycin using E-strips., Results: All the isolated organisms were uniformly susceptible to both the antibiotics. Vancomycin showed higher minimum inhibitory concentrations (MICs) as compared to linezolid MICs., Conclusion: This study suggests that linezolid and vancomycin have similar in vitro efficacy for methicillin resistant Staphyloccus aureus infections.

Introduction: The rapid spread of acquired metallo-beta-lactamases (MBLs) among major Gram-negative pathogens is an emerging threat and a matter of particular concern worldwide., Methodology: This descriptive study was conducted between January and August 2009 in the department of Microbiology, Army Medical College, National University of Sciences and Technology, Rawalpindi, to determine the frequency and susceptibility patterns of MBL-producers among carbapenem-resistant Gram-negative rods (GNRs) from clinical isolates of a tertiary care hospital. All clinical samples were processed according to standard microbiological methods. Isolated GNRs were subjected to susceptibility testing against various antibiotics by disc diffusion method according to the Clinical and Laboratory Standards Institute (CLSI) guidelines.  Carbapenem-resistant isolates were subjected to the detection of MBL production by the E-test MBL strip method., Results: Out of 50 carbapenem resistant isolates, 39 (78%) of were confirmed to be MBL producers by the E-strip method.  Acinetobacter baumannii were the most frequent MBL producers, followed by Pseudomonas aeruginosa. A total of 19 (37%) of the MBL producers were susceptible to cefoperazone-sulbactam., Conclusion: The findings strongly suggest that there is a need to track the detection of MBL producers and that judicious use of carbapenems is necessary to prevent the further spread of these organisms.

Emergence of multidrug-resistant strains of Shigella is a growing concern across the globe. Third-generation cephalosporins are used for treating infections caused by multidrug-resistant Shigellae. However, resistance to these cephalosporin antibiotics due to extended-spectrum ß-lactamases, has emerged as a new problem. So far extended-spectrum ß-lactamases producing Shigella has not been reported from Pakistan. We report such a case in Shigella flexneri from an 8-year old girl with acute dysentery.

Background and Objectives: Methicillin resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen causing significant morbidity and mortality. The aim of this study was to evaluate in vitro activities of different antibiotics against methicillin resistant Staphylococcus aureus., Materials and Method: The study was conducted over a period of one year (January 2009 - December 2009) in the Department of Microbiology, Army Medical College, the National University of Sciences and Technology, Pakistan. One hundred and thirty-nine Methicillin resistant Staphylococcus aureus isolated from the clinical specimens at Rawalpindi Military Hospital were subjected to in vitro susceptibility against various antimicrobials using Kirby Bauer disc diffusion technique., Results: All the isolated MRSA organisms were uniformly susceptible to vancomycin, linezolid and tigecycline. Other drugs which were found to be effective were chloramphenicol, and rifampacin. Most of the MRSA were isolated from pus samples., Conclusion: Vancomycin, tigecycline and linezolid were effective against methicillin resistant strains of S.aureus. This study suggests that chloramphenicol and rifampacin also have good in vitro efficacy for methicillin resistant S. aureus infections. Oral dosing option for linezolid, chloramphenicol and rifampacin can allow earlier discharge of hospitalized patients and thus reduce health care expenses as well as help reduce the chances of vancomycin resistant strains emergence.