October 9, 2018
Ramos D, Reche-Junior A, Mills DS, Fragoso PL, Daniel AG, et al. A closer look at the health of cats showing urinary house-soiling (periuria): a case-control study. J Feline Med Surg. 2018 Sep 28;:1098612X18801034.
Inappropriate urination (peeing outside of a litter box; periuria) is one of the most common reasons for a cat to present to a veterinarian, as well as a common cause for surrender to a shelter. Spraying has generally been recognized as a unique behaviour from inappropriate urination (referred to in this study as inappropriate latrining). Spraying usually occurs on a vertical surface with the cat in a standing posture, while urination is on a horizontal surface with the cat squatting. Inappropriate urination may be associated with inappropriate defecation, but spraying is usually isolated to urine.
Management of these issues is usually focused on identifying and treating underlying medical conditions, reducing triggers, and behavioural therapy. The role of medical-related lower urinary issues in spraying and periuria is not well understood, as many cats with true lower urinary disease (ie crystals, stones, infection, FIC) present with unique signs such as pain, hematuria, and stranguria. The purpose of this study was to investigate the role of lower urinary disease in cats with spraying and inappropriate urination.
Cats were recruited by a university teaching hospital with a history of urinating outside the litter box. Cats were required to come from a household with at least one periuria cat and one matched “normal” urination cat. A veterinary behaviourist evaluated urination behaviour, location, volume, timing, and other factors and classified them as spraying or inappropriate latrining. Households were not eligible if one cat sprayed and another latrining inappropriately. Pairs of cats received a full urinalysis and culture, complete blood count and serum biochemistry, and a urinary tract ultrasound. Without explanation on preliminary exams, cystoscopy was carried out in female cats with periruria if owners consented.
Twenty-one spraying case-control pairs were recruited, of which 18 finished the study. Three cats were female and 15 male, with a median age of 6.43y for cases and 6.27y for controls, and a median of 6.1 cats per household. Half of households allowed outdoor access.
Twenty-nine inappropriate latrining pairs were recruited of which 23 finished the study. Eighteen of these were female and 5 male. Average age was 4.46 years for cases and 5.21 for controls, with a median of 4.6 cats in the household. None of the cats had outdoor access.
Twenty-three case-control dyads met the criteria for cystoscopy, of which 8 agreed to the procedure. Two of the cats had increased urinary signs following cystoscopy, and in several cats the procedure could not be completed.
In the spraying group, 7 case cats had a detectable medical abnormality compared to 1 control cat (p=0.041). These included renal disease, FIC, diabetes insipidus, diabetes mellitus, and an ectopic testis. The control cat had cystolithiasis. No other clinical findings considered relevant to the lower urinary tract were found.
In the latrining group, 9 case cats had an underlying medical issue, compared to 6 control cats (p=0.365). Medical problems included chronic renal disease, leukocytosis, bladder plugs, bladder stones, and liver disease. Control cats had leukemia, bladder diverticuli, renal disease, bladder stones, hepatic disease, and ascites.
Medical conditions were found in a significant portion of both case and control cats in each of the two groups, but the difference was only significant for the sprayers. One potential confounding factor was the presence of disease in some control cats that may have no effect on elimination behaviour (ie leukemia).
The focus on multi-cat households may have introduced some bias to the study, as it may have predisposed to selecting cats with territorial stress. It also relied on owner reports of urinary behaviour, which may be difficult to assess in multi cat household (ie a single cat may be blamed when multiple cats are urinating out of the box). Cystoscopy was applied irregularly to a subset of cats, and so it is difficult to apply the cystoscopic findings to the entire group.
The authors conclude that in any cat with inappropriate urination, a full medical workup should be performed to ensure concurrent or underlying health issues are not present.
Horwitz DF. House soiling by cats. In: Horwitz DF, Mills DS and Heath S (eds). BSAVA manual of canine and feline behavioural medicine. 2nd ed. Gloucester: British Small Animal Association, 2002, pp 97–108.