The Study of Antimicrobial Resistance among Salmonella enterica Strains Isolated from Children with Gastroenteritisin in Tehran, Iran

Abstract

Background: Salmonella enterica is one of the predominant causes of the food-borne salmonellosis in humans. The aim of this study was to determine antimicrobial resistance patterns of Salmonella enterica isolated from stool samples of children with gastroenteritisin in Tehran, Iran. Methods: Stool samples of patients with diarrhea in a pediatric hospital in were collected from June 2017 to May 2018. Microbiological methods were used for identification of Salmonella. The identity of Salmonella enterica serotype enteritidis (S. enteritidis) was also confirmed by a multiplex-PCR. Antibiotic susceptibility testing was performed according to the standard procedure of the Clinical and Laboratory Standards Institute (CLSI). Results: Of 800 samples, 24 were identified as Salmonella. The most prevalent serotype was S. enteritidis (n=10, 41.7%), followed by S. paratyphi C, (n=6, 25%), S. paratyphi B (n=4, 16.7%), S. arizonae 2 (n=2, 8.3%), and S. paratyphi A (n=2, 8.3%). The highest rates of antibiotic resistance were obtained for nitrofurantoin (100%), followed by nalidixic acid (45.8%), and tetracycline (16.7%). Of 24 S. enteritidis, 9 distinct antibiotypes (Abs) were observed. In this respect, 3 isolates (12.5%) were resistant to at least three or more antibiotics. The most prevalent antibiotype was AB1 (n=8, 33%), which was indicative of resistance to nitrofurantoin. Conclusion: Considering the constant changes in antibiotic resistance patterns among food-borne pathogens over time, continuous monitoring of multidrug-resistant Salmonella isolates would definitely improve infection control strategies.

Keywords

• Antibiotic resistance
• Antibiotypes
• Diarrhea Salmonella enteritidis
• Salmonellosis.