A urinary tract blockage, also known as urethral obstruction, is a dangerous condition where a solid crystalized mass of minerals forms and blocks the urethra (the tube that transports urine from the bladder to outside the body). This prevents the cat from being able to urinate normally. Urinary tract blockages most commonly occur in male cats due to their narrow urethra, although females can also be affected.
Blockages require immediate emergency veterinary care. Left untreated, toxins will build up in the bloodstream and the kidneys will fail. This can lead to death within 24-48 hours. Therefore, it is critical to recognize blockage symptoms early and seek prompt veterinary attention.
Common symptoms of a urinary tract blockage include:[1]
- Straining or crying out while trying to urinate
- Frequent trips to litter box with only small amounts of urine passed or nothing at all
- Blood in the urine
- Hunched posture while sitting
- Licking or rubbing the genital area
- Loss of appetite
- Vomiting
- Lethargy
If a urinary blockage is suspected, immediate veterinary assessment is required. The longer the blockage persists, the higher the risk of long-term kidney damage or death.
Causes
There are several potential causes of urinary blockages in cats, including:
Crystals or stones: One common cause is the formation of crystals or stones (like kidney stones in humans) that get lodged in the urethra and block the flow of urine. This often occurs when a cat’s urine is too concentrated or acidic (Hill’s Pet Nutrition, 2020).
Urethral plugs: Inflammatory urethral plugs made up of mineral crystals and organic matter like protein can also lead to blockages, especially in male cats (Kingsdale Veterinary Hospital, 2023).
Tumors: Less commonly, tumors in the urinary tract may obstruct urine flow and cause a blockage.
Anatomical abnormalities: Some cats may have congenital narrowing or strictures in their urethra that predispose them to blockages.
Symptoms
A cat with a urinary tract blockage will show obvious signs of distress and discomfort. The most common symptoms of a blockage include:
- Straining to urinate – The cat will assume the urinating position but nothing or only a small amount of urine comes out after much effort. The cat may cry out while straining.
- Small, frequent urination – The cat tries to urinate more often but only passes small amounts of urine each time. This is from obstruction preventing normal urine flow.
- Blood in urine – Blockages cause trauma and irritation so blood may be visible in the litter box or urine. This requires urgent veterinary care.
- Crying out in pain – A blocked cat is in severe discomfort and may vocalize pain when trying to urinate or even when moving around.
Other signs can include increased thirst, lethargy, and decreased appetite as the condition progresses. Owners should monitor for any difficulty urinating and seek veterinary assessment immediately at the first signs of blockage.
Emergency
A complete urethral obstruction is a life-threatening medical emergency. If left untreated, it can quickly lead to uremia, hyperkalemia, and death. According to research, mortality rates can be over 90% if a blockage is not addressed immediately.
If you suspect your cat may have a blockage, seek veterinary care as soon as possible, even if symptoms seem mild. Do not wait to see if the condition resolves on its own. The earlier obstructions are identified and treated, the better the prognosis.
Some signs that warrant an emergency vet visit include straining to urinate, frequent and prolonged trips to the litter box, vocalizing while in the litter box, blood in the urine, and excessive licking of the genital area. Male cats are at greater risk due to their narrow urethras.
During the initial exam, the vet will check for a distended or painful bladder and perform tests to evaluate kidney values and look for electrolyte imbalances. Diagnostic imaging and urinalysis help confirm the obstruction. Once identified, the blockage will need to be relieved as quickly as possible, often by inserting a urinary catheter.
Diagnosis
Veterinarians will perform a physical exam and palpate the cat’s bladder to check for enlargement, pain, or abnormalities. According to PetMD, palpation of the bladder is a key part of diagnosing a blockage, but should only be done by a vet. Enlarged or painful bladders often indicate obstruction.
Urinalysis will also be performed to check for signs of infection, crystals, stones, or other abnormalities. This involves evaluating a urine sample under a microscope. Changes in the urine’s chemical composition may point to a blockage.
Advanced imaging such as ultrasound or X-rays can provide visual confirmation of obstructions in the urinary tract. Ultrasounds use sound waves to create images of the bladder and urethra while X-rays can reveal stones or crystals.
Bloodwork may also be ordered to assess kidney function and look for any imbalances that could contribute to blockage according to ACVS.
Treatment
The primary treatment for a urinary blockage is to relieve the obstruction through catheterization. According to PetMD, a urinary catheter will be inserted through the urethra directly into the bladder to flush out urine and crystals or stones. Sedation or anesthesia is usually required for catheter placement.
The vet will administer IV fluids to restore hydration and help flush out the urinary system. Electrolyte imbalances caused by the blockage will also be corrected through the IV fluids. Pain medication such as opioids will be given to manage discomfort.
If the blockage was caused by bladder stones or crystals, surgery may be recommended to remove them and prevent recurrence. According to the ACVS, techniques like urethrostomy, stent placement or perineal urethrostomy may be performed to widen the urethra and promote long-term urinary health.
Aftercare
After a cat has recovered from a urinary blockage, proper aftercare is crucial to prevent recurrence and support your cat’s health. Here are some of the main aspects of aftercare:
Prescription Diet: Vets usually recommend feeding your cat a prescription urinary or kidney diet after a blockage. These foods are specifically formulated to produce urine that is less concentrated and more dilute, helping to prevent crystals from forming.
Increased Water Consumption: Encouraging your cat to drink more water is vital to flushing their system and diluting the urine. Provide multiple fresh water bowls around the house. Consider getting a cat water fountain since cats prefer running water. Feed wet cat food, which has high water content.
Stress Reduction: Stress can contribute to urinary issues in cats. After a blockage, keep your cat comfortable in a quiet, calm environment away from other pets. Use calming pheromones like Feliway. Increase playtime and affection. Avoid major changes to their routine.
Prevention
There are several ways to help prevent urinary blockages in cats:
Feed a high moisture diet – Cats that eat mostly wet/canned food are less likely to develop crystals and blocks. The moisture helps them stay hydrated and flush their systems regularly. According to Hill’s Pet Nutrition, “Water consumption is an important part of flushing debris from your cat’s system and preventing blockage; try offering them water from a fountain to encourage hydration.”
Give urinary health supplements – Certain supplements like glucosamine and cranberry can help support urinary tract health and make urine less hospitable to crystal formation. FurDunkin recommends mixing supplements into wet food to increase palatability.
Provide clean, easily accessible litter boxes – Cats may avoid using a dirty litter box, leading to urine retention. Make sure boxes are scooped daily and give them multiple options, suggests PetMD. This encourages regular elimination and helps prevent blocks.
Prognosis
With prompt veterinary treatment, most cats have a guarded to good prognosis for recovery from a urinary tract blockage. However, the condition can be fatal if left untreated, with death possible in as little as 24-48 hours. According to one study, the survival rate with treatment was over 90% (Gerber, 20081).
Even after successful treatment, recurrences are unfortunately common. In one study, 36% of male cats reobstructed within 3-728 days after treatment, with a median time to reobstruction of 17 days (Gerber, 20081). Close monitoring and follow-up care are essential to catch any recurrent signs early.
When to Seek Help
You should seek veterinary help immediately if your cat shows any of the following symptoms:
- Straining to urinate – Cats with a blockage will struggle to pass even a small amount of urine. They may frequently visit the litter box but pass little to no urine. Straining is a sign of obstruction.
- Small, frequent urination – Blocked cats often try to pass urine frequently but only expel a small amount each time. This is due to the obstruction preventing normal urinary flow.
- Crying out in pain – Blockages cause immense pain and pressure in the bladder. Your cat may cry or meow in distress when trying to urinate.
- Bloody urine – In some cases the straining can cause bleeding in the urinary tract. You may notice blood in the urine or just small streaks of blood.
According to the American College of Veterinary Surgeons, urinary tract obstructions can become fatal within 3-6 days if left untreated. Do not delay in seeking emergency veterinary care if your cat shows signs of blockage. The longer the obstruction persists, the higher the risk of kidney damage or failure. Early treatment is key to preventing potentially irreversible complications.