A recent study suggests cystoscopy may cause infection from Salmonella bacteriuria.

Since salmonellosis is foodborne and typically presents GI symptoms, these findings suggest public health investigations are needed to determine the link between cystoscopy and Salmonella bacteriuria. That's according to the author, Eugene Y. H. Yeung of the University of Ottowa.

The March study ran in Infectious Disease Reports, an international peer-reviewed journal. It’s the largest study to date that investigates the association of Salmonella bacteriuria with cystoscopy. The retroactive analysis aimed to determine the odds of developing infection from the bacteria after urological intervention.

“Due to the association of Salmonella bacteriuria with cystoscopy in the current study, clinicians and laboratorians should promptly contact local public health offices when they encounter such cases,” according to the paper.

Salmonellosis is generally reportable, even though manifestation of Salmonella bacteriuria alone may not meet the definition of salmonellosis, according to the study. Public health officians should use molecular studies and genome sequencing to deteremine whether future reported Salmonella isolates are from the same source.

The analysis included all incidences of Salmonella bacteriuria in 16 affiliated hospitals in Eastern Ontario, Canada, between 2017 and 2019. During that three-year span, 74 patients presented with Salmonella bacteremia — only three of whom had prior urological procedures, none of which were cystoscopy. However, cystoscopy incidence could be underestimated because it was assumed there was no history of the procedure if it was not documented.

Based on the number of patients determined to have Salmonella bacteremia exposure during the three-year period of review, Yeung concluded the odds ratio for exposure to be 63.1 percent.

Patients presenting with Salmonella bacteriuria were significantly older than those identified with Salmonella bacteremia, the review showed. Though Salmonella species are generally identified more frequently in females than males, Salmonella bacteriuria occurred more often in men in this analysis.

The cause for infection was not determined in the course of the review, but Yeung hypothesized that ineffective reprocessing of cystoscopes could be the culprit behind the infection rates.

“Because of the multi-centered nature of the study, we could not determine whether the disinfection process of cystoscopy in each hospital was consistent with the standard of practice,” Yeung writes.

Previous studies have linked infection outbreaks associated with cystoscopy resulting from damaged reusable cystoscopes or breaches in reprocessing. The study notes reported infectious outbreaks involving Pseudomonas aeruginosa and Enterobacter cloacae following cystoscopy.

Like Pseudomonas, Salmonella forms a biofilm that allows for resistance to reprocessing techniques. And like other Enterobacteriaceae, Salmonella has the ability to attach itself in hosts and fomites.

There are also multiple reports of transmission of Salmonella from gastrointestinal endoscopes.