Objective: To monitor the constituents and resistant tendency of bacterial pathogens isolated from diarrheal patients in our hospital form 1994 to 2005 to offer the basis for guiding epidemiologic study, vaccination research and clinical treatment.
Methods: Enteric pathogenic bacteria were cultured and identified to species, group and serotype with biochemical and serologic methods and the susceptibility of bacteria to antimicrobial agents were tested.
Results: Enteric pathogenic bacteria were isolated predominantly in male patients and mainly in children and youngsters. It reached a peak from July to September every year. Shigella spp. (75.11%) was the most frequently isolated pathogens and followed by Vibrio spp. (12.7%), Salmonella spp. (6.28%), Aeromonas spp. (4.43%) and Escherichia coli (1.25%). During the period from 1994 to 2005, diarrheal pathogens had a trend of decrease especially Shigella spp. and Salmonella spp. Of the 6329 isolates of Shigella spp., 75.62% was S. flexneri and S. sonnei, S. dysenteriae and S. boydii constituted 23.98%, 0.22% and 0.01% respectively. The sensitivity of different species, group or serotype to different antimicrobial agents was not the same. S. flexneri and Aeromonas spp. were highly resistant to most of antibiotics. However, S. sonnei and Vibrio spp. had good susceptibility to antibiotics tested except trimethoprim/sulfamethoxazole and ampicillin.
Conclusion: There are many species and serotypes of enteric pathogenic bacteria causing infective diarrhea and the distribution changes gradually in Beijing. The resistance rate of enteric pathogenic bacteria to antibiotics is not the same in different species and serotypes, so strict surveillance is always needed.