Isolation & antimicrobial susceptibility of Shigella from patients with acute gastroenteritis in Western Nepal.

Department of Microbiology, Manipal College of Medical Sciences, Pokhara, Nepal.
The Indian Journal of Medical Research (Impact Factor: 1.4). 03/2006; 123(2):145-50.
Source: PubMed


Shigellae play an important role as a causative organism of acute gastroenteritis, which is a global health problem with significant morbidity and mortality in especially in developing countries. This study was carried out to determine the isolation and pattern of antimicrobial resistance of Shigella in patients with acute gastroenteritis in western Nepal.
The study included all patients with acute gastroenteritis who visited a tertiary care hospital at Pokhara, Nepal during a 2-year period (2002-2004). The isolates was confirmed as Shigella by biochemical reaction and slide agglutination test using specific antisera. Antibiotic sensitivity test was determined by agar diffusion method and minimum inhibitory concentration (MIC) of the drugs was detected.
Of the 770 stool samples, 83 (10.8%) yielded Shigella. Shigella flexneri caused 56 (67.4%) of the total cases of shigellosis followed by S. dysenteriae 12 (14.5%), S. sonnei 10 (12%) and S. boydii 5 (6%). Of the 83 isolates, 67 (80.7%) showed resistance to various drugs and 62 (74.7%) were resistant to two or more drugs. Resistance to cotrimoxazole was 80.7 per cent followed by tetracycline 74.7 per cent, ampicillin 53.0 per cent, nalidixic acid 31.3 per cent and ciprofloxacin 2.4 per cent. The MIC(50) and MIC(90) values of those drugs were also very high. All isolates were sensitive to cefotaxime and ceftriaxone.
The findings of our study suggested that Shigellae was an important etiological agent for acute gastroenteritis, with a high rate of drug resistance and requires constant monitoring in this region.

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    • "This disease remains a major public health challenge, particularly in developing countries where it is a leading cause of death (1-3). A variety of microorganisms including bacteria, viruses and parasites can be associated with severe AID in children (4-7). Many studies have reported that among the bacterial pathogens, diearrheagenic Escherichia coli (E. "
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    04/2014; 16(4):e12329. DOI:10.5812/ircmj.12329
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    • "In India, Over 70% of Shigella isolates were resistant to two or more drugs including ampicillin and co-trimoxazole during 2002 to 2007 [15] . Reports from Indonesia, Bangladesh, Malaysia, and Nepal showed increasing frequency of Shigella with multiple resistance to ampicillin, trimethoprimsulphamethoxazole , tetracycline, and nalidixic acid [16] [17] [18] [19] . "
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    Asian Pacific Journal of Tropical Disease 02/2014; 4(1):30–34. DOI:10.1016/S2222-1808(14)60309-1
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    • "Any of four subtypes of Shigella (S. dysenteriae, S. flexneri, S. boydii, and S. sonnei) can cause shigellosis . Children are at a higher risk of being affected by the disease, which might be a reflection of secondary infection from the adults as well as poor personal hy- giene [19] . Because of increasing antimicrobial resistance to Shigella, empiric treatment options are dwindling. "
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    03/2013; 27(2):103-15. DOI:10.7555/JBR.27.20120125
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