Prevalence of Selected Bacterial and Parasitic Agents in Feces from Diarrheic and Healthy Control Cats from Northern California

Background: Bacterial and parasitic agents are commonly implicated as causes of diarrhea in cats, but there is a paucity of information evaluating epidemiological and prevalence factors associated with most of these organisms in cats. Objectives: Determine the prevalence of selected enteropathogens in diarrheic and nondiarrheic cats. Animals: A total of 219 diarrheic and 54 nondiarrheic cats. Methods: Prospective study. Fresh fecal specimens were submitted for centrifugation flotation, culture, ELISA (Giardia, Cryptosporidium, Clostridium perfringens enterotoxin [CPE], and C. difficile toxin A [TcdA]) and polymerase chain reaction (PCR) testing (Tritrichomonas foetus and Campylobacter spp.). An epidemiologic questionnaire was completed for each cat. Results: Campylobacter was isolated from significantly fewer diarrheic (21/219 or 9.6%) versus nondiarrheic cats (15/54 or 27.8%, P = .001), and was detected in 74 of 131 cats (56.5%) via PCR. Campylobacter jejuni, C. helveticus, and C. upsaliensis were detected in 6.8, 100, and 44.6% of the 74 cats. Multiple Campylobacter spp. were identified in 47.3% of these cats. All cats were negative on fecal culture for Salmonella and for C. difficile TcdA via ELISA. CPE was detected in 9/219 diarrheic (4.1%) and in 1/54 nondiarrheic cats (1.9%, P = .69). Cats < 2 years were significantly more likely to be infected with intestinal parasites (P <.001). Conclusions and Clinical Importance: Routine fecal cultures and toxin immunoassays for detection of bacteria are of limited diagnostic value in diarrheic cats. Molecular-based testing is superior to fecal cultures for detection and identification of Campylobacter spp., but positive test results do not correlate to the presence of disease.