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Urinary tract infection (UTI) is one of the bacterial infections frequently documented in humans. Proteus mirabilis is associated with UTI mainly in individuals with urinary tract abnormality or related with vesicular catheterism and it can be difficult to treat because of the formation of stones in the bladder and kidneys. These stones are formed due to the presence of urease synthesized by the bacteria. Another important factor is that P. mirabilis produces hemolysin HpmA, used by the bacteria to damage the kidney tissues. Proteus spp. samples can also express HlyA hemolysin, similar to that found in Escherichia coli. A total of 211 uropathogenic P. mirabilis isolates were analyzed to detect the presence of the hpmA and hpmB genes by the techniques of polymerase chain reaction (PCR) and dot blot and hlyA by PCR. The hpmA and hpmB genes were expressed by the RT-PCR technique and two P. mirabilis isolates were sequenced for the hpmA and hpmB genes. The presence of the hpmA and hpmB genes was confirmed by PCR in 205 (97.15 %) of the 211 isolates. The dot blot confirmed the presence of the hpmA and hpmB genes in the isolates that did not amplify in the PCR. None of the isolates studied presented the hlyA gene. The hpmA and hpmB genes that were sequenced presented 98 % identity with the same genes of the HI4320 P. mirabilis sample. This study showed that the PCR technique has good sensitivity for detecting the hpmA and hpmB genes of P. mirabilis.

Aim: To determine the occurrence and characteristics of Shiga toxinproducing Escherichia coli (STEC) in drinking water supplies treated and untreated. Methods and Results: Drinking water samples (n = 1850) were collected from 41 municipalities in the north of Paran a State between February 2005 and January 2006. Escherichia coli isolates (n = 300) were recovered from water and investigated for the presence of virulence markers related to STEC by PCR. STEC isolates recovered were then characterized for both phenotypic and genotypic traits. A total of 12 isolates (11 from untreated water and one from treated water) were positive for stx, including five positive for both stx1 and stx2, two positive for stx1 and five positive for stx2. None of the STEC isolates contained eae, but other virulence genes were observed such as ehxA (100%), saa (100%), lpfA O113 (75%), iha (42%), subAB (25%) and cdtV (8%). Multidrug resistance was identified in 25% of the STEC isolates. The 12 STEC isolates belonged to seven distinct serotypes and pulsed-field gel electrophoresis typing revealed the presence of two clusters and two clones in this region. Conclusion: Drinking water, especially from untreated water supplies, can be source of STEC strains potentially pathogenic for humans. Significance and Impact of the Study: The investigation of the drinking water supplies for pathogenic E. coli, as STEC, may be useful to prevent waterborne outbreaks.

Exotic psittacine birds have been implicated as reservoir of diarrheagenic Escherichia coli (E. coli), including enteropathogenic E. coli (EPEC) and Shiga-toxin producing E. coli (STEC). Here, we present a genotypic and phenotypic characterization of typical EPEC/STEC hybrid strains isolated from exotic psittacine birds. The strains were positive for eae, bfpA, and stx2f genes, belong to serotype O137:H6 and ST2678. Two strains were subject to whole genome sequencing, confirming the presence of the virulence factors of both E. coli pathotypes. Phenotypical in vitro tests confirmed their ability to adhere to HeLa cells and cause cytotoxicity to Vero cells. The rabbit ileal loop assays showed the attaching and effacing lesion, in addition to inflammatory process and overproduction of intestinal mucus. This is the first report of hybrid typical EPEC/STEC (O137:H6/ST2678) strains isolated from companion psittacine birds and the results suggest zoonotic risks.