Genotyping virulence and resistance profiles in salmonella isolated from diarrheic children in Nairobi city, Kenya.

Abstract

Aim: To characterize salmonella virulent and antibiotic resistance genes in children with diarrhea in Nairobi city, Kenya. Background: Salmonella species carry virulent genes whose expression correlate with severity of salmonellosis. Effective treatment of salmonellosis by antibiotics is threatened by expression of antibiotic resistant genes. Methods: In a cross-sectional study, a total of 374 children below five years of age presenting with diarrhea at Mbagathi County Hospital were recruited. Stool microbiology test was used to detect Salmonella species. Polymerase chain reaction was employed to detect virulent and antibiotic resistant genes. Results: Salmonella species was isolated in 9 (2.4%) children. A total of 9 (100.0%), 7 (77.8%), 9 (100.0%) and 6 (66.6%) of the isolates harbored invA, Hila, sopB, and Stn virulent genes, respectively. None (0.0%) of the isolates was resistant to gentamycin but 7 (77.8%), 7 (77.8%), 9 (100.0%), 8 (88.9%), 7 (77.8%), 6 (66.7%) and 5 (55.6%) of Salmonella species were resistant to ampicillin, ceftriaxone, streptomycin, ciprofloxacin, chloramphenicol, erythromycin, and tetracycline, respectively. Ampicillin (citm), ceftriaxone (bla CMY), streptomycin (aadA1), gentamycin (aac(3)-IV), ciprofloxacin (qnr), chloramphenicol (catA1), erythromycin (ereA), and tetracycline (tetA) resistant gene was detected in 6 (85.7%), 6 (85.7%), 9 (100.0%), 8 (100.0%), 6 (85.7%), 6 (100.0%), and 5 (100.0%) of Salmonella isolates which were phenotypic resistant to ampicillin, ceftriaxone, streptomycin, ciprofloxacin, chloramphenicol, erythromycin and tetracycline, respectively. Conclusion: Salmonella species expressing virulent and antibiotic resistant genes is an important cause of gastroenteritis in children in Kenya.