<p>High Rates of Antimicrobial Resistance and Virulence Gene Distribution Among<em> Shigella</em> spp. Isolated from Pediatric Patients in Tehran, Iran</p>

Abstract

Background: Shigella continues to be important causes of acute pediatric diarrhea worldwide. Shigella produces numerous virulence factors involved in colonization and invasion into epithelial cells which eventually result in the disease. The present study was conducted to evaluate the prevalence of virulence genes and to investigate antibiotic resistance profiles among Shigella isolates obtained from pediatric patients in Iran. Methods: A total of 141 Shigella isolates were collected between March 2017 and September 2018 from stool of children under 14 who were suspected to have shigellosis. Shigella isolates were identified using standard microbiological and serological tests and antimicrobial susceptibility testing was carried out via Kirby-Bauer disk diffusion method. In addition, the presence of seven virulence determinants including ipaH, ipaB, ipaC, ipaD, ipgD, sen, and virA were evaluated using PCR. Results: S. sonnei (78.7%) was the most prevalent shigella spp. among children with shigellosis followed by S. flexneri (19.9%) and S. boydii (1.4%). Antimicrobial susceptibility testing revealed that most of the isolates were considered as multidrug-resistant (MDR) strains. Our findings also showed a high resistance rate against trimethoprimsulfamethoxazole in Shigella isolates. The prevalence of ipaH, ipaC, sen, ipaD, virA, ipaB, and ipgD were 100%, 95.7%, 95.7%, 94.3%, 93.6%, 92.9%, and 80.8%, respectively. Conclusion: The current study revealed that S. sonnei was the predominant species isolated from children with shigellosis in Iran. Our results also indicated a high distribution of type III secretion system effector protein-encoding genes and high multidrug-resistance among shigella spp. in Iran. Therefore, it is suggested that antimicrobial susceptibility testing be performed prior to antibiotic prescription.

Antibiotic resistance pattern in Shigella species isolated from children with acute diarrhea in Tabriz city, Iran

“…Of these, 70% belonged to the S.sonnei, 28.9% belonged to the S. flexneri and 1.1% belonged to the S. boydii (21). In 2020, Karimi-Yazdi et al (22), reported a prevalence of S. sonnei of 78.7%, S. flexneri of 19.9%, and S. boydii of 1.4%. Abbasi et al (16), examined multidrugresistant Shigella infection in children with diarrhea, out of 19 positive Shigella specimens, 21% belonged to flexneri species and 78.9% belonged to sonnei species.…”

Frequency and Antimicrobial Resistance of Shigella Species in Iran During 2000-2020

“…The frequency and antibioticresistant patterns of Shigella species are changing rapidly over time. So, antibiotic treatments are typically suggested to decrease the symptoms of Shigella infections (6)(7)(8)(9). Selecting an appropriate antibiotic for the treatment of Shigella infections is necessary because multidrug resistance (MDR) species can appear from many mechanisms, such as a decrease in cellular permeability, extrusion of drugs by active efflux pumps, and overexpression of drugmodifying in Shigella genomes (10)(11)(12)(13).…”

<p>Virulence-Related Gene Distribution Among <em>Shigella</em> Isolates in Anhui, China: The Association with Antimicrobial Resistance</p>

“…In our study, all the isolates harbored ipaH , which was consistent with previous reports. 27 Most of the Shigella isolates in this study harbored ipaA, ipaB, ipaC , and ipaD , genes that regulate the secretion and translocation of several effector proteins and play a key role in intracellular actin polymerization and depolymerization. 28 The ial gene was reported to be responsible for Shigella epithelial cell penetration and cell-to-cell dissemination.…”