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Abstract Shigellosis (bacillary dysentery) continues to be a major public health burden, particularly in developing countries. During the period from March 2019 to December 2020 , 62 Shigella isolates out of 920 fresh fecal specimens of diarrheic children admitted to Pediatric Department at Tanta University Hospitals (The Diarrhea and Nutrition Unit) , Banha Children Specialist Hospital , EL-Mahalla Fever Hospital and Mansoura Fever Hospital were recovered . The incidence of shigellosis associated diarrhea was 6.7% . Identification of the tested isolates was confirmed using microscopical, cultural, standard biochemical tests as well as serological tests . S.flexneri was the most frequently isolated (61.3%) serogroup, while 32.3% and 6.5% were S.sonnei and S.boydii , respectively . S. dysenteriae spp. was not detected in our study. It was found that Shigella associated diarrhea was more prevalent in children aged between 2 and 2.5 years. Common manifestations included watery diarrhea (85.5 %) , fever (45.2 %) , and abdominal pain (25.8 %) . bloody diarrhea , however, occurred in only 12.9% of cases . PCR technique was used for the detection of genes specific for the genus (ipaH1) , species (wzy , wbgZ , ipaH for S.boydii, S.sonnei and S.flexneri respectively) , major virulence genes namely ipaH , virA , icsA , sigA , sat , sepA , pic , set1A , set1B , sen/ospD3 , stx1 , stx2 and genes encoding resistance to commonly used antibiotics in clinical practice (blaCTX-M & blaTEM , qepA & qnrs , aadA1 ,sul1 genes). abstract The set1A/set1B that encode Shigella enterotoxin 1 (ShET-1) were found in 50% of only S.flexneri isolates and absent in other Shigella species .On the other hand , stx1/stx2 encoding ShET-1 and pic encoding protein involved in colonization were not detected in any of the studied isolates . Regarding antibiotic resistance genes it was found that the tested isolates harboured all except blaCTXM antibiotic resistance gene. All the studied 62 Shigella isolates were tested for susceptibility to each of 17 different antimicrobial agents. High frequency of resistance was observed to Amoxicillin + Clavulanic acid (91.9%) , Cefotaxime (77.4%) , Ceftazidime (69.4%) , and Trimethoprim/Sulfamethoxazole (69.3 %) , while relatively low rate of resistance was found to colistin (17.7%) , tetracyclines (9.7%) and Norfloxacin (9.7 %) . Imipenem demonstrated the highest activity where all tested isolates were sensitive to this drug. Resistance to antimicrobial drugs in Shigella spp. can result from several mechanisms, such as extrusion of drugs by active efflux pumps, decrease in cellular permeability, and overexpression of drug-modifying and -inactivating enzymes or target modification by mutation. Phenotypically was found that 49 out of 62 (79 %) Shigella isolates produced β-Lactamase enzymes . Molecular studies revealed that genes encoding antibiotic resistance like blaTEM for penicillins resistance , qepA & qnrs for quniolones and flouroquinolones , aadA1 gene for aminoglycosides & sul 1 gene for Cotrimoxazole (Trimethoprim / Sulfamethoxazole) were harboured by Shigella species isolates .On the other hand, the penicillin resistance gene , blaCTX-M was not detected among tested isolates |