Understanding Urinary Tract Issues in Cats: FLUTD and Crystals

Straining in the litter box, urinating outside of it, or crying out while trying to go are the telltale signs of a lower urinary tract issue in cats, and these problems are more common than most owners realize. Feline lower urinary tract disease, known as FLUTD, is an umbrella term covering several conditions that affect the bladder and urethra, and one of the most talked about contributors is the formation of urinary crystals, which can cause irritation and, in some cases, a dangerous blockage.

At Pawtown Veterinary Care, every cat deserves attentive, thorough care, especially for conditions that are easy to miss in their early stages. Our team provides routine cat checkups that include urinary health screening, so we can catch problems before they become emergencies. Understanding what FLUTD is, what causes it, and how crystals play a role can help you recognize the early warning signs and act quickly.

What Is FLUTD?

FLUTD is not a single disease but rather a collection of conditions that affect the lower urinary tract. According to the American Veterinary Medical Association, urinary stones are one common cause of FLUTD, though research published in the National Institutes of Health identifies idiopathic cystitis as the most commonly diagnosed cause, meaning no clear underlying reason can be found in many cases. Other contributing factors include bacterial infections, urethral plugs, and anatomical abnormalities. Because symptoms can look similar regardless of the underlying cause, a proper diagnosis is essential for effective treatment.

Recognizing the Symptoms

Symptoms of FLUTD vary in severity, but there are key signs every cat owner should know. Watch for the following:

• Straining to urinate or producing only small amounts of urine despite frequent trips to the litter box.
• Blood in the urine, which may appear pink or reddish, or crying out while attempting to urinate.
• Urinating outside the litter box in unusual locations or excessively licking the genital area.

These signs should never be brushed off, particularly if your cat is straining without producing urine. That may indicate a complete urethral blockage, which is a medical emergency. Male cats are at higher risk for life-threatening blockages due to their narrower urethras, so a straining male cat with little or no urine output needs to be seen the same day.

The Role of Crystals in Urinary Health

Urinary crystals are microscopic mineral formations that develop in concentrated urine. The two most common types found in cats are struvite crystals, which form in alkaline urine, and calcium oxalate crystals, which develop in acidic urine. Small amounts of crystals do not always cause symptoms on their own, but they can accumulate and lead to bladder inflammation, discomfort, and urethral plugs that completely block urine flow.

What Causes Crystals to Form?

Several factors increase a cat’s risk of developing urinary crystals. Diet plays a significant role, since cats that eat primarily dry food tend to consume less water, which leads to more concentrated urine where crystals are more likely to form. A sedentary lifestyle, obesity, stress, and genetics can all contribute as well, and indoor male cats are among the most commonly affected, though crystals can develop in any cat.

Diet and Prevention

Diet is one of the most effective long-term tools for managing urinary crystal risk. The Cornell Feline Health Center notes that cats fed an exclusively dry diet are more likely to develop lower urinary tract disease than cats fed canned food or a combination of canned and dry, since wetter food increases overall water intake and produces more dilute urine. Diluted urine gives crystals less concentrated mineral content to form around in the first place.

A prescription urinary diet formulated to manage urine pH and mineral concentration is often part of a long-term plan for cats who have already had one urinary episode. Encouraging water intake with a pet fountain, multiple water bowls placed around the house, or adding water to meals can potentially support the same goal for cats who are prone to concentrated urine.

Diagnosis and Treatment

Our diagnostic services allow us to evaluate your cat’s urinary health thoroughly, including urinalysis to detect crystals, blood, or signs of infection. Imaging, such as X-rays or ultrasound, may also be recommended to check for urinary stones or blockages. The treatment approach depends on the specific diagnosis and may include dietary changes, increased water intake, medications to relieve inflammation or address infection, or, in more serious cases, a procedure to remove an obstruction.

If your cat is showing any signs of a urethral blockage, do not wait. Our urgent care team is available during business hours to help when time is critical, since a complete blockage can become fatal within 24 to 48 hours if it is not addressed. If your cat has had a prior episode of straining, inappropriate urination, or blood in the urine, our post on why cats urinate outside the litter box covers additional behavioral and medical causes worth ruling out.

Urinary Health at Pawtown Veterinary Care

Dr. Erin Miller and Dr. Lauren Stayer founded Pawtown Veterinary Care to give Bend cats and dogs complete, in-house care so your cat does not have to be referred elsewhere when they need you most. We know how stressful it can be when a beloved pet is in pain, and we strive to make the experience as calm and comforting as possible for both of you.

From routine screenings to urgent interventions, our team is equipped to support your cat’s urinary health at every stage, and those symptoms will not go away on their own. Same-day appointments are available so your cat can be seen quickly when it matters most, so reach out to us today through our contact form and let our team provide the focused, compassionate care your cat deserves.

Frequently Asked Questions About Cat FLUTD and Urinary Crystals