Characterization of helicobacter pylori and Escherichia coli from stool of human and pet animals

Abstract EN

The recent isolation of Helicobacter pylori from cats and human has potentially important public health implications as well as other bacteria associated with H.pylori in stool samples such as E.coli.

A total of 202 stool samples from human, cats and dogs were examined for detection of H.pylori and E.coli.

For isolation of H.pylori, 150 stool samples were cultivated on Dent,s medium (modified skirrow,s medium) containing selective Dent,s antibiotic supplement.

while the remaining 52 samples were cultivated on MacConkey, Eosine methylen blue media in attempt to isolate other associated bacteria.

Colonies grossly similar to H.pylori were tested for catalase, oxidase and urease test.

All human samples were tested serologically by using rapid stool antigen test (SAT).

PCR assay was performed on bacterial isolates and directly from stool samples by extraction of DNA from stool by boiling method.

Positive cultures were subjected to serology testing and PCR.

45samples from humans gave positive results with rapid H.pylori stool antigen test (HPSA).

Results revealed that H.pylori was detected in tested samples from human and cat at a rate of 52.8%, 33.3%, respectively and could not be detected in dog.

Also detected serologically at percentage of 84.9% in human stool samples.

H.pylori could not be detected by PCR, while the other 52 samples were found positive for Escherichia coli, isolation at a percentage of 48%.

Nine serogroups of E.coli (O1, O20, O55, O86, O114, O125, and O146) were detected in 9 samples (3 samples from each species).

All serotypes were positive for Iss and Fim genes.

From all stool samples subjected for isolation of E.coli we obtained 15 isolates which were introduced to PCR.

14 isolates were positive for E.coli genus (phoA gene).

9 isolates were used for detection of virulence genes (Iss, Fim, and Tsh genes).

8 isolates were positive for (Iss and Fim) gene.

None was positive for (Tsh) gene.

We conclude that H.pylori is very difficult to culture due to the fastidious nature of the organism and its transport and culture requirements.

Also H.pylori is the main species of Helicobacter present in human.

While dogs and cats harbour many gastric Helicobacter like organisms (GHLOs) and E.coli isolated from human, dogs and cats share the same characters and virulence genes.