Relationship of bacterial infection in urine and calculi to canine urolithiasis.

In 26 dogs treated surgically for urolithiasis, bacteriological examination of the urine and the interior of calculi showed that infection was present in both materials in 14 cases. Infection with phosphate calculi, present in 13 of these 14 dogs, was associated with a variety of bacteria including Staphylococcus aureus, Staph epidermidis, Streptococcus faecalis, Escherichia coli and Proteus spp. In a follow-up examination of 16 dogs, organisms different from the original isolates were recovered from some cases. The significance of the persistence of viable bacteria within canine bladder calculi is discussed.