BackgroundStaphylococcus aureus is the most commonly isolated organism from the different clinical samples in hospital. The emergence and dissemination of methicillin resistant Staphylococcus aureus (MRSA) and growing resistance to non-beta-lactam antibiotics is making treatment of infections due to this organism increasingly difficult.MethodsThis study was conducted to determine the frequency of Staphylococcus aureus isolated from different clinical samples, rates of MRSA and full antibiotic susceptibility profiles. Clinical samples were cultured and Staphylococcus aureus was identified using standard microbiological methods recommended by the American Society for Microbiology (ASM). Methicillin resistance was confirmed using cefoxitin and oxacillin disks. Inducible clindamycin resistance was identified using D-zone test.ResultsFrom the processed samples, 306 isolates of Staphylococcus aureus were recovered. All the isolates were susceptible to vancomycin and teicoplanin. Methicillin resistance was observed in 43.1% of isolates while inducible clindamycin resistance in 12.4% of the isolates.ConclusionsThe results of our study reveals that rates of resistance to commonly prescribed antibiotics in Staphylococcus aureus clinical isolates is high. In particular, rate of methicillin resistance is alarming, prompting concern on the rational use of antibiotics and vigilant laboratory-based surveillance of resistance rates in Nepal.

Escherichia coli is the major organism causing the urinary tract infection, wound infection and respiratory tract infection. A total of 2376 samples of urine, wound swab and sputum were analyzed for identification of bacterial isolates and their antimicrobial susceptibility pattern.

INTRODUCTION: Peritonsillar abscess is a common complication of acute tonsillitis. Its management consists of aspiration or surgical drainage followed by appropriate antibiotics. Appropriate antibiotic treatment depends on the common organisms associated with infection and their antibioticsensitivity pattern in local scenario. METHODS: Pus samples aspirated from diagnosed cases of peritonsillar abscess and submitted for culture and sensitivity in last two years were included in this study. Identification of different microorganisms was made on the basis of the microscopic findings, observation of their colony morphology and standard biochemical reactions. Susceptibility pattern to commonly used antibiotics were determined by Clinical Laboratory Standards Institute (CLSI) guidelines. RESULTS: Altogether 24 pus samples were included in the study. Positive culture was obtained from 18 samples. Among them one organism was isolated from 13 samples whereas from five samples multiple organisms were isolated. From six samples no organisms could be cultured. Altogether Streptococcus pyogenes was isolated from 12 samples and Staphylococcus aureus from five samples. Other isolated organisms included Haemophlilus influenzae, Pseudomonas aeruginosa, Escherichia coli and Enterococcus species. Penicillin was effective for Streptococcus pyogenes whereas Staphylococcus aureus was resistant to it. Cloxacillin was found to be effective for Staphylococcus aureus. Ciprofloxacin and Ceftazidime were found to be effective for both organisms. CONCLUSIONS: Streptococcus pyogenes and Staphylococcus aureus were more commonly associated with peritonsillar abscess. Streptococcus pyogenes were sensitive to penicillin but all Staphylococcus aureus were resistant to it. This fact should be considered in clinical practice for management of peritonsillar abscess. KEYWORDS: Bacteriology, Peritonsillar abscess, Susceptibility pattern.

Background: Staphylococcus aureus, versatile pathogen causes many serious and life threatening infections. Resistant S aureus has become a serious matter of concern. The antimicrobial susceptibility profile of local isolates is essential for the selection of appropriate therapy for the management of staphylococcal infections. Objective: To find out the current status of antimicrobial resistance among the clinical isolates in our set up. Method: S aureus isolated from the clinical specimens submitted to the microbiology unit of clinical laboratory services, BP Koirala Institute of Health Sciences (BPKIHS) hospital were studied. Isolation and identification of S aureus was done by standard microbiological technique. Results: A total 300 S aureus isolates were obtained from various clinical specimens. S aureus showed susceptible to chlorampenicol (95%), tetracycline (94.3%), cefotaxime (93.3%), erythromycin (89%), ciprofloxacin (88.35%) and gentamicin (78%).Sixty four percent of isolates were found to be resistant to co-trimoxazole and 26% were methicillin resistant (MRSA). Nearly half (52.66%) of S aureus showed resistance to penicillin. All the isolates were susceptible to vancomycin in disc diffusion method. It was isolated frequently from pus 223(74%) followed by blood (14%). Forty eight percent of isolates were from abscess, followed by sepsis (17%). Conclusion:Resistant S aureus is a common pathogen causing a wide spectrum of infections in our set up. Existence of MRSA among local isolates is a serious matter of concern. Although no isolate exhibited resistance to vancomycin, screening test and MIC determination are recommended in monitoring the response to therapy and for early detection of impeding resistance among local strains.

Health Renaissance, January-April 2013; Vol. 11 No.1; 17-22 DOI: http://dx.doi.org/10.3126/hren.v11i1.7595