Characterization of Aeromonas hydrophila Isolated from Patients with Diarrhea

Aeromonas hydrophila was isolated from 12 (5.3%) of 225 patients with acute gastroenteritis.The present study was determined the virulence of A. hydrophila obtained from patients with diarrhea, among 12 A. hydrophila isolates obtained from stool, 83.3%, 91.6%, 83.3%, 75%, 75%, 50% produced β-haemolysin, protease ,phospholipase, DNase, slime(viscous glycoconjugate material), and have the adhesion, respectively. The isolates were tested for their susceptibility to 21 antibiotics, high level of resistance was observed to Penicillin, Carbenicillin, Amoxicillin/Clavulanic acid, followed by high level of susceptibility towards Azithromycin 100%, Ofloxacin 100%, Meropenem 100%, Cefepime 91%, Streptomycin 91%, Aztreonam 91%. Minimum inhibitory concentrations (MICs) of A.hydrophila isolates to certain antibiotics, azithromycin, ofloxacin, chloramphenicol and cefepime, was done by agar dilution method, azithromycin and ofloxacin have the lowest MICs 1-32μg/ml, 1-128μg/ml, respectively. Exposure of A. hydrophila to sub-MICs of such antibiotics azithromycin , ofloxacin, chloramphenicol and cefepime, reduced the percentage of haemolysin, protease ,phospholipase ,DNase and slime production.