Feline urethal plugs: 2010
In the past three decades, the composition of uroliths in cats and dogs has been variable. In this article, the third of three installments, we evaluate current trends of feline urethral plugs to determine their implications for our patients.
Struvite continues to predominate
Why have there been significant shifts in the prevalence of calcium oxalate and struvite in uroliths during the past 30 years, while the prevalence of struvite and calcium oxalate in feline urethral plugs has not significantly changed? The answer is not obvious to us. Whatever the reasons, in recent years there has been a dramatic decline in the frequency of urethral plugs submitted for quantitative mineral analysis. And there's been a parallel decline in the frequency of perineal urethrostomies associated with urethral obstruction.
Struvitolytic and prevention foods
Not all struvite urethral plugs are prevented by dietary manipulation. The apparent ineffectiveness of dietary manipulation in some cats may be due to poor owner and/or patient compliance. We must remain vigilant. One important way to monitor future trends in the mineral composition of urethral plugs is to send them to a reputable laboratory that uses contemporary techniques for evaluating the mineral composition of uroliths and urethral plugs.
Editor's note: With the support of an educational gift from Hill's Pet Nutrition, as well as contributions from veterinarians and pet owners worldwide, the Minnesota Urolith Center is providing quantitative urolith analysis at no charge. Online submission, e-mail notification and electronic retrieval of results are available. With a database of more than 675,000 samples, the veterinary community is offered the latest information on urolith trends, treatment and prevention suggestions. For details, visit http://urolithcenter.org/.
Carl A. Osborne, DVM, PhD, Dipl. ACVIM, is professor of medicine at the College of Veterinary Internal Medicine at the University of Minnesota. Jody P. Lulich, DVM, PhD, Dipl. ACVIM, is the co-director of The Minnesota Urolith Center and professor of Veterinary Internal Medicine at the University of Minnesota.