Search

Introduction: spp. is a growing global health concern due to increasing multiple drug resistance, commonly resulting in therapeutic failure. Integrons are gene expression systems run by integrase genes. The aims of this study were detection of class I, II and III integrons and assessment of antimicrobial resistance in spp. isolated from acute pediatric diarrhea patients.Materials and methods: From January to December 2015, were isolated from 310 non-duplicative diarrheal stool samples in Children’s Medical Center, Tehran, Iran. The isolates were analyzed for their antibiotic susceptibility using CLSI guidelines Multiplex PCR was used for amplification of I, II and III integron-associated integrase () genes.Results: Of 310 stool samples, 16 (5.2%) were positive for in 7 of them and in 9 of them were identified. Results of the antimicrobial susceptibility test showed that 6.2%, 50%, 31.2%, 6.2%, 81.2%, 56.2% and 31.2% of the isolates were resistant to gentamicin, chloramphenicol, nalidixic acid, ciprofloxacin, tetracycline, ampicillin and trimethoprim-sulfamethoxazole, respectively. Multiplex PCR results revealed that 6.2% (1/16), 31.2% (5/16), 50% (8/16) of isolates carried I, iII and both I/lI genes. No class were detected.Discussion: In this study, multidrug resistance was seen in isolates similar to that in isolates from other geographical areas. This is possible due to inappropriate use of antimicrobials. Furthermore, prevalence of multidrug resistance was significantly linked to the presence of integrin genes. Conclusion: A class 2 integron plays a role in presence of multidrug resistance in spp. It is vital to prevent the spread of antibiotic resistance through continuous monitoring.

Aim: infection is an important global health problem in developing countries where hygiene is poor and hence shigellosis is a main cause of diarrhoea-associated mortality and morbidity, particularly in children under the age of five. The bacterial entry into colon and rectal epithelial cells has been named ‘bacterium-directed phagocytosis’. This term highlights that the bacteria actively stimulate their own uptake into non-professional phagocytes. The aim of this study was to demonstrate the invasion of HEp-2 cells by spp. isolated from acute pediatric diarrhea in Tehran, Iran.Methods: Three-hundred and ten non-duplicative diarrheal stool samples were collected from the children admitted to Children’s Medical Center in Tehran, Iran. Samples were cultured and suspected colonies were identified by routine microbiological and biochemical tests. The invasion of the two isolated spp. to HEp-2 cells was studied.Results: Of 310 stool samples, 16 (5.2%) spp. were isolated, including seven (43.7%) and nine (56.3%) . Four (44.4%) and seven (42.8%) showed invasive phenotype to HEp-2.Conclusion: and are reported as the most prevalent spp. in nature which infect humans. Invasion of various cell lines gives the chance of survival to spp. This ability causes more virulent infections in the host. Despite costly and time consuming cell culture techniques, the current method described in this paper is reliable for detecting invasive behavior of spp. Results have also shown that not all the spp. are able to invade intestinal epithelial cells.

Shigella flexneri has been the most frequent cause of shigellosis in children in Iran. To evaluate the changes in frequency of serogroups, 302 Shigella species were isolated in 2003 from hospitalized children, aged less than 12 years, with acute diarrhoea in Tehran, Iran. The number of collected S. sonnei, S. flexneri, S. boydii, and S. dysenteriae isolates was 178 (58.9%), 110 (37.4%), 10 (3.3%), and 4 (1.3%) respectively. Most (94%) S. sonnei isolates were resistant to co-trimoxazole. They were, however, relatively or completely sensitive to 15 commonly-used antibiotics. The extracted plasmids showed 12 different profiles with two closely-related patterns constituting 70% of the total isolates. Ribotyping, using PvuII, HindIII or SalI restriction enzymes, generated a single pattern for all S. sonnei isolates. Data suggest that S. sonnei has become the predominant serogroup in children in the hospitals of Tehran. [ABSTRACT FROM AUTHOR]