ISSN 1990-7974 (Print)
ISSN 1990-7982 (Online)
Distribution of serotypes and antimicrobial resistance of Streptococcus pneumoniae in a children's hospital in Nepal
Sherchand JB1, Joshi AR2, Gauchan P3, Amatya J4
1Jeevan Bdr Sherchand, MSc Trop. Med. PhD (U.K.); Professor, Dept of Microbiology and Chief of Health Research Laboratory, 2Ashish Raj Joshi (MSc Medical Microbiology); Kathmandu College of Science and Technology, Kalimati, 3Punita Gauchan (MSc Medical Microbiology)Research Officer, Tribhuvan University Institute of Medicine, Health Research Laboratory, Department of Clinical Microbiology, Maharajgunj, Kathmandu, Nepal, 4Jyoti Amatya (MSc Medical Microbiology), Assistant Professor in Microbiology, Kathmandu College of Science and Technology, Kalimati, Nepal.
Introduction: Streptococcus pneumoniae in low number is a part of normal nasopharyngeal and oropharyngeal flora of many healthy persons and also children, which generally remains harmless unless provoked by viral infections such as common cold, influenza etc. In this situation, pneumococcus is secondary pathogen but may be primary pathogen in immunocompromised people. Bacterial colonization of nasopharynx starts immediately after birth without development of disease. Objectices: The study was conducted to determine the prevalence of nasopharyngeal colonization with S pneumoniae, to determine their antibiotic susceptibility pattern and to determine distribution of different serotypes. Methods: Hospital based prospective study was conducted from February 2007 to September 2007. All the specimens were inoculated into 7% sheep blood agar and incubated in 5-10% CO2 atmosphere at 37*C for 24 hours. S pneumoniae was identified by colony morphology, Gram's stain, optochin susceptibility test and bile solubility test. Antibiotic susceptibility test was performed by modified Kirby-Bauer disc diffusion method. The in vitro susceptibility of the Oxacillin resistant isolates to Penicillin was determined by the E-test. Serotypes were determined by bactetrial co-agglutination using the Pneumotest Kit (Statens Serum Institut, Denmark) with 12 pooled antisera. Results: In the study, 34.6% of the children were found to be nasopharyngeal carriers of S pnemoniae among which 50.8% were male and 49.2% were female. Cephotaxime (100%), Chloramphenicol (100%) and Erythromycin (98.5%) were most effective antibiotic against S penumoniae and the least effective was Cotrimoxazole (60%). 15.4% were found to be resistant to Oxacillin. On performning E-test of Oxacillin resistant strains against Penicillin, all were found to be susceptible to Penicillin. The isolated strains were found to belong to 16 different serotypes whereas 8% were Non-typeable. Conclusion: Carriage rate is similar both in male and female. Penicillin resistance has not arisen in S pneumoniae isolated from nasopharynx which is causing problem world wide.
Key words: Children, Nasopharyngeal swab, S pneumoniae, Serotype, E-test
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Full text (PDF):Journal of Nepal Paediatric Society
