Multilocus sequence typing, clinical characteristic, and drug resistance of Salmonella typhimurium in 93 children / 中华实用儿科临床杂志

ABSTRACT

Objective:To investigate the multilocus sequence typing (MLST), clinical manifestations, and drug resistance of Salmonella typhimurium in children, thus providing references for the diagnosis, treatment, and prevention of pediatric Salmonella typhimurium infection.Methods:The clinical data of patients with Salmonella typhimurium serotypes confirmed by stool or blood culture between November 2017 and October 2020 were retrospectively collected from Fujian Maternity and Child Health Hospital.MSLT and drug susceptibility test were performed on Salmonella typhimurium isolated from the samples. Kruskal- Wallis test, Chi- square test, and Fisher′ s exact probability method were employed for data analyses. Results:Salmonella typhimurium was cultured from clinical samples of 96 children, of which, 93 samples were effective, including 92 stool samples and 1 blood sample from 53 boys(56.99%) and 40 girls(43.01%). The median age of disease onset occurred at 12.0 (8.5-22.0) months, with peak months of onset ranging from July to October.According to MLST classification, 93 children were divided into ST34 classification( n=58), ST19 classification( n=22) and other classification( n=13). Respiratory symptoms were significant different among MLST classification, and ST34 type Salmonella typhimurium enteritis was more commonly accompanied by respiratory symptoms ( χ2=17.657, P<0.001; Cramer V=0.421, P<0.001). There were significant differences in the drug sensitivity to Ampicillin ( χ2=8.774, P=0.033), Piperacillin tazobactam ( χ2=6.713, P=0.022), Ciprofloxacin ( χ2=20.780, P<0.001), Sulfamethoxazole ( χ2=15.364, P=0.001), Ampicillin sulbactam ( χ2=17.626, P=0.001) and Levofloxacin ( χ2=25.648, P<0.001) among 3 groups.No significant difference was found in the sensitivity to Ceftriaxone ( χ2=1.027, P=0.621), Ceftazidime ( χ2=7.637, P=0.059), Cefepime ( χ2=6.099, P=0.116) and Cefoperazone/Sulbactam ( χ2=2.405, P=0.649). All MLST types were sensitive to Imipenem and Meropenem. Conclusions:Salmonella typhimurium infection mainly affects infants, with the peak months of onset ranging from July to October.MLST34 is the main serotype, accompanied respiratory symptoms.Antibiotics should be selected according to drug sensitivity, and third-generation cephalosporins can be selected empirically without drug susceptibility test results.