Feasibility study evaluating a veterinary point-of-care urine culture system for diagnosing septic peritonitis.

OBJECTIVE

To evaluate the use of a veterinary point-of-care urine culture system (POCUCS) for the diagnosis of septic peritonitis.

DESIGN

Prospective feasibility study performed between August 2017 and April 2018.

SETTING

Private referral hospital.

ANIMALS: Twenty samples of naturally occurring canine peritoneal effusion collected via aseptic abdominocentesis.

PROCEDURES: Point-of-care urine culture systems were inoculated and incubated according to manufacturer's instructions. The presence of bacterial growth, estimation of colony-forming units/mL of bacteria, and organism identification were recorded. Bacterial growth and organism identification on POCUCS were compared to an aerobic culture performed at a commercial microbiology laboratory. Serial dilution and subsequent culture on a POCUCS of a confirmed Escherichia coli infected peritoneal effusion and negative control sample were performed to determine the lowest concentration of bacteria detectable.

RESULTS

There were 10 septic and 10 aseptic samples of peritoneal effusion confirmed by aerobic laboratory culture. Of the 10 culture-positive samples, 8 were culture-positive on the POCUCS. The sensitivity and specificity of the POCUCS for the detection of bacteria in peritoneal effusion were 80.0% and 100%, respectively. The POCUCS lowest limit of detectable bacteria in peritoneal effusion was 1000 CFUs/mL.

CONCLUSIONS

The POCUCS evaluated in this study was less sensitive and less rapid for diagnosing septic peritonitis than blood glucose to peritoneal effusion glucose ratio and plasma lactate to peritoneal effusion glucose ratio. This POCUCS is not recommended as a tool for diagnosing septic peritonitis.