Comparative Detection and Quantification of Arcobacter butzleri in Stools from Diarrheic and Nondiarrheic People in Southwestern Alberta, Canada

摘要

Arcobacter butzleri has been linked to enteric disease in humans, but its pathogenicity and epidemiology remain poorly understood. The lack of suitable detection methods is a major limitation. Using comparative genome analysis, we developed PCR primers for direct detection and quantification of A. butzleri DNA in microbiologically complex matrices. These primers, along with existing molecular and culture-based methods, were used to detect A. butzleri and enteric pathogens in stools of diarrheic and nondiarrheic people (n = 1,596) living in southwestern Alberta, Canada, from May to November 2008. In addition, quantitative PCR was used to compare A. butzleri densities in diarrheic and nondiarrheic stools. Arcobacter butzleri was detected more often by PCR (59.6%) than by isolation methods (0.8%). Comparison by PCR-based detection found no difference in the prevalence of A. butzleri between diarrheic (56.7%) and nondiarrheic (45.5%) individuals. Rates of detection in diarrheic stools peaked in June (71.1%) and October (68.7%), but there was no statistically significant correlation between the presence of A. butzleri and patient age, sex, or place of habitation. Densities of A. butzleri DNA in diarrheic stools (1.6 ± 0.59 log₁₀ copies mg?1) were higher (P = 0.007) than in nondiarrheic stools (1.3 ± 0.63 log₁₀ copies mg?1). Of the 892 diarrheic samples that were positive for A. butzleri, 74.1% were not positive for other bacterial and/or viral pathogens. The current study supports previous work suggesting that A. butzleri pathogenicity is strain specific and/or dependent on other factors, such as the level of host resistance.