The Study For Salmonella Resistant And The Enterotoxin Gene In Children With Diarrhea

Objective：To investigate our region Salmonella enteritis Children's clinical features,the drug resistance and the relationship of toxin with it in recent years；at the sametime to compare the virulence differences between drug-resistant Salmonella strainsand sensitive Salmonella strains,provide the basis for judgement and treatment ofclinical conditions.Methods：80strains Salmonella are isolated from the stool of Salmonella enteritischildren who come to children's hospital of Jiangxi province from April2004toDecember2009, to distinguish and determine the serotypes of Salmonella byserological agglutination test method,then detection18kinds of antimicrobial drugsusceptibility by Kerby-Bauer disc diffusion method. At the same time,detection theenterotoxin gene (spvA, spvB, rck) by PCR, combined with clinical features,analysisthe clinical features, the drug resistance and the relationship of toxin with it ofchildren with Salmonella enteritis. Salmonella is develop with2ml PH4.0fresh LBmedium, properly diluted and inoculated LB agar plate, calculate the flat on thecolony-forming units; Salmonella fluid tube into6to8week old female micestomach,2weeks after the mice in each group recorded the number of mortality inmice, the liver and spleen index of the mortality mice and the presence of diarrheaand other performance treated with saline as a control,to understand the differencesin virulence between drug-resistant Salmonella strains and sensitive Salmonellastrains.Results：Fever, diarrhea are the major clinical manifestations of children withSalmonella enteritis, Salmonella typhimurium are the major serotypes of childrenwith Salmonella enteritis(70/80,87.50％).80strains of Salmonella were differentlevels of resistance to other antibiotics, all sensitive to imipenem and Meropenem,.66strains of Salmonella are multiple drug-resistant strains,8strains are suspiciousproducing AmpC enzyme,17strains are suspicious producing ESBLs.Salmonellatyphimurium are significantly higher than other Salmonella in multidrug resistance(x~2 =30.921,p=0.001), all Salmonella genes contain spvA,but all Salmonella contains19spvB gene and16rck gene, the ratio of high fever in children is higher in spvBpositive strains than spvB negative strains(x~2=7.544,p=0.006),the ratio of bloodymucus in children is higher in spvB positive strains than spvB negative strains(x~2=6.163,p=0.013). Salmonella strains in the acidic environment of the growth willdecrease, but the only drug sensitive bacteria in cultured for1hours and2hours afterbacterial counts than the uncultured have been reduced obviously(p=0.046,p=0.005),and resistant strains was significantly less than susceptible strains for the halfthe lethal dose of mice(t=2.885,p=0.034).Conclusion：Fever, diarrhea are the major clinical manifestations of children withSalmonella enteritis, Salmonella typhimurium are major pathogens in children withSalmonella enteritis. Salmonella typhimurium are significantly higher than otherSalmonella in multidrug resistance,the infected person of spvB positive strains aremore clinical manifestations of hight fever and bloody mucus,the toxic power ofresistant strains is Stronger than the sensitive strains,Rational use of antibiotics to bebased on susceptibility results in clinical.