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Antibiotic resistance exhibited by Staphylococcus aureus is a growing global concern. This work was undertaken to determine the prevalence rate of inducible clindamycin resistant S. aureus in nasal sample and detect ermB gene in the isolates with inducible clindamycin resistance. Nasal swabs were collected from the school children and cultured on Mannitol Salt Agar (MSA) and Blood Agar (BA) for observation of colony morphology. Gram staining and biochemical test (catalase, oxidase, O-F and coagulase) were performed for further identification of the bacteria. The Kirby-Bauer disc diffusion method using a cefoxitin disc (30 μg) was used to detect methicillin resistant S. aureus (MRSA). All, the MRSA isolates were tested for ermB gene by PCR amplification. Among 64 S. aureus isolates, 17 (26 %) were MRSA. The prevalence of Inducible clindamycin resistant S. aureus (iMLSB) isolates was 23.4 % in the S. aureus isolates. All the isolates of MRSA were resistant to penicillin, while 88.2 % were sensitive to gentamicin. The prevalence of ermB gene was 3.1 % in the total S. aureus isolates and 11.7 % MRSA showed the presence of this gene. Routinely performing a D-test in laboratory will guide the clinicians on the rationale use of clindamycin and improving hygienic practices can reduce the spread of inducible clindamycin resistance.

Aim: Resistance to methicillin and Macrolide–Lincosamide and Streptogramins B and their association with erm genes in Staphylococcus aureus are unknown in Nepal. Materials & methods: Nonduplicate nasal swabs from 160 school children were collected from April to September 2018 and processed using standard microbiological procedures. Results: Out of 160 samples, 64 (40%) were S. aureus in which 17 (26.6%) were methicillin-resistance Staphylococcus aureus (MRSA). D-test identified 15 (23.4%) as inducible clindamycin-resistant, which were more prevalent in MRSA (76.4%) than methicillin-sensitive S. aureus (MSSA; 4.2%). 18.7% of isolates harbored the ermC gene followed by ermA (15.6%) and ermB (3.1%), and were more in MRSA than MSSA. Conclusion: To prevent treatment failure by inducible resistance, D-test must be performed on erythromycin-resistant and/or clindamycin-sensitive isolates.

Objective: To determine the status of isolation blood stream serotypes of enteric fever pathogens and their antibiotic susceptibility patterns and to guide clinicians for appropriate therapy. Methods: Samples were examined by microbiological techniques to identify the causative agent and determine their antimicrobial susceptibility patterns by Kirby-Bauer disk diffusion methods and interpreted as per Clinical and Laboratory Standards Institute guidelines. Results: Among 403 blood samples, 76 (18.85%) showed growth for Salmonella isolates. Distribution of Salmonella typhi and Salmonella paratyphi A isolates were found to be 54% and 46% respectively. Among 76 Salmonella isolates, 28 (36.84%) were from male and remaining 48 (63.15%) were from female belonging to all age-groups. Multidrug-resistance was found to be 17% among the Salmonella isolates. Nalidixic acid resistance was 73.68% in Salmonella with higher proportion in Salmonella paratyphi A (85.7%) in comparison to Salmonella typhi (63.42%). Salmonella isolates demonstrated 100% susceptibility to azithromycin, ceftriazone, ciprofloxacin, ofloxacin and imipenem. Conclusions: The need of continual surveillance of resistance levels to guide clinicians for appropriate therapy based on the antibiotic susceptibility pattern for Salmonella isolates is sustained with discouragement in misuse of antibiotics prior to prescription as multidrugresistance-nalidixic acid resistant strains.

Introduction: Tuberculosis remains a worldwide public health problem despite the highly effective drugs and vaccines are available making tuberculosis a preventable and curable disease. The objective of this study was to compare the different laboratory diagnostic methods of tuberculosis and determine its prevalence. Methodology: Morning sputum samples were collected from suspected cases of pulmonary tuberculosis and preceded for Ziehl Neelsen staining, fluorescent staining (auramin-O) and mycobacterium culture in Lowenstein Jensen medium. Results: Total 78 suspected cases of pulmonary tuberculosis were included in this study among them 53 were male and 25 were female. Out of 78 cases, 46 cases were found to be culture positive. In culture positive cases (83%) were found to be M. tuberculosis and (17%) were found to be slow grower, fine colonies, AFB positive but niacin test negative (mycobacteria other than M. tuberculosis ). In the direct microscopic examination by Ziehl Neelsen stained smear 26 samples were found to be acid fast bacilli and one sample was culture negative but acid fast bacilli positive. In fluorescent stained smear 34 samples were found to be positive for acid fast bacilli and 5 samples were culture negative but acid fast bacilli positive. Culture was accepted as gold standard, the sensitivity of direct microscopic examination was found 56.5% for Ziehl Neelsen staining and 73.9% for fluorescent staining respectively. Conclusion : In culture positive cases M. tuberculosis and mycobacteria other than M. tuberculosis was found to be 83% and 17% respectively, it was found higher in male than female. Fluorescent microscopy is superior to Ziehl Neelsen microscopy but gives more false positive result than Z-N staining. Combining of Ziehl Neelsen and fluorescent staining is better than fluorescent staining alone. DOI: http://dx.doi.org/10.3126/saarctb.v11i2.12427 SAARC J TUBER LUNG DIS HIV/AIDS, 2014;XI(2), page: 1-6