Multi-locus sequence type analysis ofShigellaspp. isolates from Tehran, Iran.
OBJECTIVE
Strains ofShigellaspp. can cause shigellosis, or bacillary dysentery. that is a public health problem worldwide. The aim of this study was to describe the population structure and genetic relatedness of multidrug resistantS. sonneiandS. flexneriisolated during a one year period from children with diarrhea in Tehran, Iran.


METHODS
A total of 70Shigellaspp. were detected during the study period. Twenty MDR isolates ofShigellaspp. were randomly selected and used in this study. Bacterial identification was performed by conventional biochemical and serological and confirmed by molecular method. After antimicrobial susceptibility testing, we used Multilocus sequence typing (MLST) for subtyping isolates.


RESULTS
We found 14Shigella sonneiand 6Shigella flexneriisolates. Results of MLST showed five sequence types (ST) (145, 152, 241, 245, 1502) and BURST analysis revealed the largest number of single locus variant (SLV) and highest frequency (FREQ) for ST152. ST 152 with nine members was predicted as the founder by BURST. Frequency for ST 1502 and ST 245 was four isolates and the least frequency was seen for ST 241 and 145 with one and two members, respectively. ST 145 and ST 245 were described as singletons in BURST. All isolates with ST145 and ST245 were identified asShigella flexneri.


CONCLUSIONS
Annual Multi locus sequence typing of MDRShigellawould help us in better understanding of dominant species and comparing our results with the same studies in other countries especially our neighbor countries in source tracking purposes.
Antimicrobial Resistance Research Center, Rasul-e-Akram Hospital, Iran University of Medical Sciences, Tehran, Iran.
Shadi
S
Shahsavan
Antimicrobial Resistance Research Center, Rasul-e-Akram Hospital, Iran University of Medical Sciences, Tehran, Iran; Department of Anatomy, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Maliheh
M
Nobakht
Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Abdolaziz
A
Rastegar-Lari
Molecular Microbiology Research Center, Shahed University, Tehran, Iran.
Parviz
P
Owlia
Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
Bita
B
Bakhshi
Multidrug resistant; Multilocus sequence typing; Shigella