Owing to the scarce evidence about the multidrug-resistant (MDR) beta-lactamase-producing Shigella isolates in Iran, this study aimed to evaluate the occurrence of extended-spectrum beta-lactamases (ESBL) and AmpC β-lactamases in Shigella species collected in the southwest of Iran. This study was conducted on Shigella species isolated from stool samples of pediatric patients aged less than 15 years suffering from diarrhea. These isolates were identified by bacteriology tests, serotyping, and polymerase chain reaction (PCR). The antibiotic resistance was determined by disc diffusion. The production of ESBLs and AmpC was investigated by phenotypic confirmatory tests and PCR. In total, 79 Shigella isolates, including 46.8% (n = 37) of S. flexneri and 53.2% (n = 42) of S. sonnei, were isolated, respectively. The most effective antibiotic was imipenem with 93.7% of susceptibility followed by ampicillin (29.1%), and cotrimoxazole (30.4%).The resistance rates of ceftriaxone, ceftazidime, and cefotaxime were 41.8%, 34.2%, and 41.8%, respectively. Also, a total of 57 (72.2%) isolates showed MDR profiles. The phenotypic tests showed that 43.0% (34/79) of isolates can produce ESBLs, and no one was positive for ApmC. The frequency of bla_TEM and bla_CTX-M were 30.4% and 32.9%, respectively, while the bla_PER, bla_SHV, and AmpC genes were not detected. The ESBL-producing isolates had a significant (p-value ˂ 0.05) resistance rate against ceftriaxone, ceftazidime, cefotaxime, cefepime, erythromycin, and amikacin. The significant prevalence of MDR Shigella isolates harboring ESBL genes highlights the need for effective surveillance measures to prevent the more spread of drug resistance among species.

由于在伊朗产生多药抗性（MDR）β-内酰胺酶的志贺菌分离株的证据稀少，本研究旨在评估在收集到的志贺氏菌属中广谱β-内酰胺酶（ESBL）和AmpCβ-内酰胺酶的发生伊朗西南部。这项研究是针对从15岁以下腹泻的儿科患者的粪便样本中分离的志贺氏菌进行的。这些分离物通过细菌学测试，血清分型和聚合酶链反应（PCR）进行鉴定。通过盘扩散确定抗生素抗性。通过表型确认试验和PCR研究了ESBLs和AmpC的产生。总共有79株志贺氏菌分离株，其中46.8％（n = 37）分离出弗氏链球菌和5.3.2％（n = 42）的S. sonnei。最有效的抗生素是亚胺培南，其敏感性为93.7％，其次是氨苄西林（29.1％）和考特莫唑（30.4％），头孢曲松，头孢他啶和头孢噻肟的耐药率分别为41.8％，34.2％和41.8％。另外，共有57（72.2％）个分离株显示出MDR谱。表型测试表明，有43.0％（34/79）的分离株可以产生ESBLs，没有人对ApmC呈阳性。bla _TEM和bla _CTX-M的频率分别为30.4％和32.9％，而bla _PER，bla _SHV，并没有检测到AmpC基因。产生ESBL的分离株对头孢曲松，头孢他啶，头孢噻肟，头孢吡肟，红霉素和丁胺卡那霉素具有显着（p值˂0.05）耐药率。带有ESBL基因的MDR志贺氏菌分离株的流行十分突出，这表明需要采取有效的监视措施来防止耐药性在物种之间进一步扩散。