Pathogen & Infectious Disease 2017; 3: e1570. doi: 10.14800/pid.1570; © 2017 by Pauline Getanda, et al. http://www.smartscitech.com/index.php/pid Page 1 of 8 Genetic characterization and evaluation of antimicrobial resistance patterns of human salmonella typhi isolates in kenyatta national hospital in nairobi, kenya Pauline Getanda 1 , Francis Kariuki 1* , Nduhiu Gitahi 2* , Nyamongo Onkoba 3* , Gerald Juma 1* , Peter Kinyanjui 1* , Atunga Nyachieo 1,4* , Joseph Kamau 1,4* 1 Department of Biochemistry, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya 2 Department of Public Health, Pharmacology and Toxicology, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya 3 Tropical and infectious Diseases, Institute of Primate Research, P.O. Box 24481-00502, Nairobi, Kenya 4 Molecular Biology Unit, Institute of Primate Research, P.O. Box 24481-00502, Nairobi, Kenya * These authors contributed equally to this work Correspondence: Pauline Getanda E-mail: paulinegetanda@gmail.com Received: June 07, 2017 Published online: July 26, 2017 The rapid increase and subsequent management of Typhoid fever in Kenya has been complicated by the emergence and rise of antimicrobial resistance to the Salmonella Typhi pathogen. This situation is yet to be addressed due to the paucity of information regarding the circulating strains and their antimicrobial resistance profiles. This study was hence designed to genetically characterize and evaluate the antimicrobial resistance patterns of human Salmonella Typhi isolates circulating among patients in Kenyatta National Hospital the largest referral health facility in Kenya. Fifty (n=50) Salmonella Typhi archived sample isolates were obtained from stool samples of patients suffering from typhoid fever who attended the facility from 2010 to 2015. The isolates were evaluated for phylogenetic relationships targeting 16s rRNA gene sequences and antimicrobial susceptibilities against a panel of 12 drugs by disk diffusion method. Phylogenetically, the isolates clustered close to Salmonella Typhi strain CT18 and its plasmid pHCM1 and plasmid IncHI1 of Salmonella Typhi strain R27 both associated with drug resistance. Antimicrobial susceptibility tests showed that 73% of the isolates were resistant to the Aminopenicillin, Sulfonamide, Phenicol and Aminoglycoside classes of drugs. A resistance of between 7% to 19% was observed for the Beta-lactamase, Fluoroquinolone and Cephalosporin classes of drugs. Only one of the isolates was fully susceptible to all the antimicrobial drugs used. A total of 23% of the isolates were intermediately resistant to all the 12 drugs used. The high resistance patterns of Salmonella Typhi evidenced necessitates the re-evaluation of the currently used antibiotic regimen and also underscores the importance of continued drug resistance monitoring for this pathogen. Keywords: Salmonella Typhi; Antimicrobial resistance; Phylogenetic; Susceptibility To cite this article: Pauline Getanda, et al. Genetic characterization and evaluation of antimicrobial resistance patterns of human salmonella typhi isolates in kenyatta national hospital in nairobi, kenya. Pathog Infect Dis 2017; 3: e1570. doi: 10.14800/pid.1570. Copyright: © 2017 The Authors. Licensed under a Creative Commons Attribution 4.0 International License which allows users including authors of articles to copy and redistribute the material in any medium or format, in addition to remix, transform, and build upon the material for any purpose, even commercially, as long as the author and original source are properly cited or credited. RESEARCH ARTICLE