Feline ureteral obstruction is a complex medical condition that poses serious threats to a cat's kidney function and overall health. In veterinary medicine, it is not to be confused with urethral obstruction, a more commonly encountered issue in small animal practice. To deepen our understanding of feline ureteral obstruction, this blog post delves into an article published in the Journal of Feline Medicine and Surgery. Authored by Alexandra J Kennedy and Joanna D White, both experienced professionals in referral practice in Australia, the article uncovers critical insights about the condition and potential preventive measures.

The authors set out to address a significant gap in the knowledge surrounding feline ureteral obstruction. In particular, they aimed to identify potentially modifiable risk factors for ureteral obstruction that could inform preventive strategies. Unlike urethral obstruction, which is typically managed non-surgically, unilateral feline ureteral obstruction often necessitates surgical intervention. The acute kidney injury associated with ureteral obstruction can be life-threatening, making prevention a vital aspect of feline healthcare.

Methodology: Case-Control Study

To accomplish their objectives, Kennedy and White conducted a case-control study. Cases in the study were defined as cats with either ureteral obstruction or elevated creatinine concentrations, both conditions known to be associated with UO.

Cases included cats with:

• Ureteral obstruction (ureteroliths 13/18: unknown 5/18-confirmed with pyelography) 

• A creatinine concentration greater than 140 μmol/l with both UO (ureteroliths: 6/10; blood clots: 3/10; pyonephrosis 1/10 and pyelectasia greater than 5mm on abdominal ultrasonography.  

• Controls, on the other hand, were cats without any evidence of ureteral obstruction on the basis of a thorough evaluation, encompassing history, physical examination, and abdominal ultrasound.

The study collected and analyzed data on several variables, including the age, sex, breed, housing conditions (indoors or mixed), and diet of the cats involved. The authors were particularly interested in examining diet as a potential risk factor for feline ureteral obstruction.

Diet was classified into three categories:

1. Predominantly dry food

2. Mixed diet

3. Predominantly moist (canned) food

Key Findings

The study's analysis included 168 cats, comprising 28 cases and 140 controls. Several interesting findings emerged from the study:

1. Age, sex, breed, housing conditions, and total calcium levels did not exhibit significant associations with ureteral obstruction.

2. Diet, however, was identified as a significant factor. Cats that were predominantly fed dry food were found to be 15.9 times more likely to develop ureteral obstruction compared to those on a predominantly moist food diet. There was no notable difference in the risk of UO between cats on a mixed diet and those on a predominantly moist food diet.

The study's findings underscore the potential impact of diet on the risk of feline ureteral obstruction. Specifically, the research indicates that cats primarily fed dry food may face a considerably higher risk of developing this serious medical condition. In contrast, cats on predominantly moist food diets exhibited a lower risk.

These findings highlight the importance of diet formulation as a simple and cost-effective method for reducing the risk of ureteral obstruction in cats. It is important for veterinarians and cat owners to consider these insights in feline healthcare and nutrition.

As the field of veterinary medicine continues to advance, insights from studies like this will play a pivotal role in enhancing feline care, improving preventive strategies, and ultimately ensuring the well-being of our feline companions. This article compliments the excellent webinars on the subject, by Benoit Cuq, called Feline Ureteral Obstructions Part 1 and Part 2, go check them out!