In Vitro Study on the Pathogenicity of Proteus Species Isolated from Urinary Tract Infections

Proteus spp is a common etiologic agent of urinary tract infections, especially in the elderly catheterized population. Urinary tract infection with Proteus spp. could lead to serious complications such as renal stones. A number of virulence factors had been identified in this organism including flagella, urease enzyme, fimbriae and outer memberane proteins (OMPs).A total of 143 specimens were collected from patients diagnosed clinically as UTIs, renal calculi and renal abscess and also from patients in intensive care unit with long catheterized. Proteus isolates were identified in only 13 out of 143 specimens (9.09%). from these 13 Proteus isolates, 12 (92.3%) were identified as Proteus mirabilis leaving only one (7.69%) as Proteus penneri. For comparison purposes, additional 7 clinical and environmental Proteus isolates from other sources were included in the study.Isolates identification was based mainly on urease, growth on TSI with H2S production and phenylalanine deaminase tests. The characteristic swarming phenomenon was detected in these isolates.All Proteus isolates showed complete resistance to amoxicillin, cephradine, streptomycin, rifampicin, chloramephenicol and tetracycline. Proteus isolates showed susceptibility rates of 40% to ceftazidime and ciprofloxacin and susceptibility rates of 50%, 55%, and 70% to ceftriaxone, augmentin and cefotaxime, respectively. All Proteus isolates (100%) were susceptibile to gentamicin.Proteus isolates were subjected to plasmid extraction by alkaline-extraction method and agarose gel electrophoresis.