Age-based ultrasonographic criteria for diagnosis of autosomal dominant polycystic kidney disease in Persian cats.

OBJECTIVES: The aim of this study was to establish ultrasound criteria for the diagnosis of autosomal dominant polycystic kidney disease (ADPKD) in Persian cats. METHODS: Eighty-two Persian cats were assessed using renal ultrasound and genotyped for the C→A transversion in exon 29 of PKD1. The animals were also submitted to hematological characterization, serum biochemistry analyses and urinalysis. RESULTS: Age, sex and neutering status did not differ between ADPKD (n = 12) and non-ADPKD (n = 70) cats. After integrated molecular genetics/ultrasonographic analysis, the presence of at least one renal cyst was sufficient to establish a diagnosis of ADPKD in animals up to 15 months of age. Two or more cysts were required for diagnosis in cats aged 16-32 months, and at least three cysts warranted diagnosis of ADPKD in animals aged 33-49 months. Finally, four or more cysts led to diagnosis in cats aged 50-66 months. Although cats with ADPKD exhibited higher serum calcium levels than non-affected cats, hematological, urinalysis and other biochemical parameters did not differ between the two groups. CONCLUSIONS AND RELEVANCE: Integrated analyses of imaging and molecular genetics data enabled, for the first time, the establishment of age-based ultrasonographic criteria for the diagnosis of ADPKD in Persian cats. The development of imaging criteria is particularly relevant and useful in the clinical setting given the current limitations to access and the cost of molecular genetics-based diagnostic tests.

A closer look at the health of cats showing urinary house-soiling (periuria): a case-control study.

OBJECTIVES: The aim of this study was to perform a case-control medical evaluation of cats from multi-cat households presenting with inappropriate latrining and spraying behavior. METHODS: Owners of 18 'spraying' and 23 'latrining' cats with normal control subjects available from the same households were recruited for a case-control study. Otherwise overtly healthy dyads (each dyad consisting of a case cat and a control cat) were brought together to the veterinary hospital of the University of São Paulo for a medical work-up (ie, physical examination, complete blood count, biochemical profile, urinalysis and urine culture, abdominal ultrasound of the urinary system and in females, where possible, cystoscopy). RESULTS: Medical problems were identified with similar frequency in the 'sprayers' (38.9%), 'latriners' (39.1%) and controls of the latrining group (26.1%), but not the controls of the spraying group (5.5%). The difference between 'cases' and 'controls' from spraying households was significant. Common potential health-related changes include renal insufficiency, cystitis and bladder lithiasis. Renal calculi, higher creatinine levels (within normal reference interval) and 'glomerulations' (detected during cystoscopy) were also found in the remaining sprayers and latriners that were considered clinically healthy. Post-cystoscopy, a new form of periuria occurred in two cats (one sprayer and one latriner). CONCLUSIONS AND RELEVANCE: These results indicate that spraying or latrining behavior in the home, as well as living with a cat that is not using the litter box as a latrine, are all associated with a higher level of urinary tract abnormalities; living with a cat that is spraying, however, does not have this association. The findings also suggest that both forms of periuria might be associated with interstitial cystitis. We therefore conclude that all cats with periuria need to be carefully evaluated medically and that treatment of latrine-related problems should consider all cats in the house, whereas spraying may be more focused on the individual displaying the problem.