A urethral blockage is a potentially serious condition that can occur in both male and female cats. It prevents the normal flow of urine through the urethra, the tube that carries urine from the bladder to the outside of the body. If left untreated, a urethral blockage can lead to a buildup of toxins in the bloodstream and eventual kidney failure. That’s why it’s important for cat owners to know the signs of a potential urethral blockage and what to do if they suspect their cat may have one. In this article, we’ll cover the causes, symptoms, diagnosis, and treatment for urethral obstructions in cats. We’ll also provide tips on how to prevent this condition in the first place.
Causes
There are several potential causes of urethral blockages in cats:
– Bladder stones (uroliths): One of the most common causes is the formation of stones or crystalline structures (known as uroliths) in the bladder. These stones can become lodged in the narrow urethra as they attempt to pass out of the body, causing an obstruction. Certain types of stones, such as struvite and calcium oxalate, are more likely to cause blockages than others.
– Urethral plugs: In male cats, another common cause is the formation of urethral plugs. These plugs consist of debris, epithelial cells, protein, and minerals that collect in the urethra. This material eventually hardens into a plug that blocks urine flow.
– Narrowing of the urethra: Any anatomical abnormality that leads to narrowing of the urethral opening can increase the risk of obstructions. This includes scar tissue from prior trauma, inflammation, tumors, or even an unusually narrow urethral opening present from birth.
– Bladder or prostate infections: Bacterial infections of the bladder or prostate gland can also lead to urethral blockages in some cases. The inflammation and swelling spreads to the urethra, narrowing the opening.
– Anatomical differences: Male cats are at greater risk than females due to their longer, narrower urethra. Obstructions most commonly occur in the narrow area where the urethra passes through the penis.
Symptoms
The most common signs that a cat may have a urethral obstruction include:
– Straining or crying out while trying to urinate
– Frequent attempts to urinate with only small amounts of urine passed
– Blood in the urine
– Excessive licking of the genital area
– Difficulty defecating
– Loss of bladder control or dribbling urine
– Dehydration
– Lethargy
– Lack of appetite
– Vomiting
In severe cases, a blocked cat may collapse, have pale gums, a weak pulse, shallow breathing, or even enter a coma. This indicates a buildup of toxins in the bloodstream and requires emergency veterinary treatment.
Diagnosis
To diagnose a urethral obstruction, the veterinarian will perform a physical exam and obtain a medical history from the owner. They will palpate the cat’s abdomen to feel for an enlarged, firm bladder that cannot be expressed. The vet will also check for external signs of trauma, masses, or swelling along the urinary tract.
Initial diagnostic tests usually include:
– Urinalysis: Checking a urine sample for signs of infection, crystals, and other abnormalities
– Bloodwork: Assessing kidney values, electrolyte imbalances, and more
– Radiographs (x-rays): Images can reveal bladder stones and help evaluate the urethra
– Ultrasound: Allows visual assessment of the bladder and urethra
– Catheterization: Passing a narrow tube into the urethra to check for blockages
Urinalysis
A urinalysis is one of the first diagnostic tests performed when a urethral obstruction is suspected. This involves evaluating a fresh urine sample for the following:
– Presence of bacteria, white blood cells, or red blood cells, indicating inflammation or infection
– Crystalline structures that may be causing bladder stones
– Concentration of urine to assess kidney function
– pH level, which influences stone formation
If the cat is completely blocked, the veterinarian may use ultrasound guidance to perform a technique called cystocentesis. This involves passing a needle directly through the skin into the bladder to obtain a urine sample for analysis.
Bloodwork
A basic blood panel allows the vet to check for several markers of overall health and kidney function, including:
– Elevated kidney values such as BUN and creatinine, indicating reduced kidney function
– Increased liver enzymes that may point to liver damage from toxins
– Electrolyte imbalances
– Low red blood cell count (anemia) from blood loss into the urine
– High white blood cell count indicating infection or inflammation
– Low blood pH from metabolic toxins
In a cat with an obstruction, bloodwork helps assess the severity and allows the vet to monitor kidney function after relief of the blockage.
Radiographs (X-rays)
Abdominal x-rays are often performed to evaluate the lower urinary tract in a cat suspected of having a urethral obstruction. Radiographs can reveal:
– Bladder or urethral stones appearing as radiopaque densities
– Bladder distension and wall thickening
– Anatomical abnormalities like urethral strictures
– Prostate enlargement in male cats
– Free gas in the bladder wall indicating possible bladder rupture
However, not all types of stones are visible on radiographs. Contrast studies where dye is injected into the urethra may provide additional information about the location and nature of the obstruction in equivocal cases.
Ultrasound
An abdominal ultrasound allows real-time visualization of the bladder, urethra, and prostate gland. The vet can assess:
– Bladder size, wall thickness, and any masses
– Size, shape and location of bladder stones
– Urethral narrowing or obstructions
– Prostate enlargement or abscesses
Ultrasound is useful for detecting radiolucent bladder stones not visible on x-rays. It can also guide needle placement during cystocentesis urine collection.
Catheterization
One way to both diagnose and treat an obstruction is to pass a narrow catheter through the urethra into the bladder. Catheterization can confirm if a true obstruction exists and allow temporary urine drainage. It also facilitates collection of an uncontaminated urine sample directly from the bladder. However, this procedure is somewhat invasive and requires sedation.
Treatment
The first priority in treating a blocked cat is to stabilize them and relieve the obstruction. This is done by:
– Catheterization to open the urethra and promote urine flow
– Flushing the bladder with sterile saline to wash away debris
– IV fluids to correct dehydration and electrolyte abnormalities
– Medications like pain relievers and muscle relaxants
– Sedation or anesthesia if required for catheter placement
In many cases, once the obstruction is relieved the cat begins urinating normally again within 24-48 hours. Any underlying causes still need to be addressed to prevent recurrence:
Dissolving bladder stones
– Prescription urinary diets – formulated to create an environment unfavorable to stone formation
– Medications to help dissolve certain stone types
– Surgery to remove large stones if diet therapy fails
Managing urethral plugs and strictures
– Urinary acidifiers to prevent plug formation
– Surgery to remove plugs or scar tissue causing strictures
– Penile tie-back operation for stubborn recurring plugs
Treating infections
– Antibiotics guided by urine culture and sensitivity results
– Addressing underlying causes like bladder or prostate disease
Preventing recurrence
– Prescription urinary diets for life
– Increased water consumption to dilute urine
– Regular urinalysis to monitor for stones or plugs
– Possibly medications depending on cause
– Avoiding any known risk factors
Prompt veterinary care is essential for the best outcome in cats with urethral obstructions. In severe cases, the toxins building up can quickly lead to kidney failure, metabolic derangements, and even death if left untreated. However, with aggressive therapy most cats with obstructions fully recover if addressed early enough. Recurrence is common, so continued monitoring and prevention steps are key.
Prevention
While urethral obstructions sometimes arise unpredictably, there are steps cat owners can take to reduce the risk:
– Feed only veterinary-approved prescription urinary diets
– Provide abundant fresh water daily
– Limit dry food and feed wet food whenever possible
– Avoid urinary salt supplements
– Feed smaller, more frequent meals
– Monitor urine volume and color
– Bring cats in for regular urine checks
– Address medical conditions like diabetes or hyperthyroidism
– Maintain a healthy body weight to reduce stones
– Keep litter boxes extremely clean to promote usage
– Reduce stressors in the household
– Have male cats neutered to decrease prostate issues
Conclusion
Urethral obstructions represent a true veterinary emergency requiring immediate treatment. Cat owners need to monitor for symptoms like straining to urinate, blood in the urine, crying out, and excessive licking of the genital region. Any suspicion of a blockage warrants an urgent vet visit for diagnosis and relief of the obstruction. Left untreated, toxins can accumulate leading to kidney failure and possibly death. But with aggressive veterinary therapy and steps to prevent recurrence, most cats with obstructions fully recover and go on to live normal lives again. Being aware of the risk factors, prompt medical attention, and proper ongoing management are all key to protecting cats from this dangerous condition.