Signs of Kidney Infection in Cats: What to Watch For
Kidney infections in cats, medically referred to as pyelonephritis, can be challenging to detect early because their initial symptoms are often subtle. The kidneys play a crucial role in filtering blood, maintaining hydration, regulating blood pressure, and producing hormones. When a kidney infection compromises these vital functions, the effects can be widespread and serious.
Understanding Kidney Disease and Infection in Cats
Kidney disease in cats generally presents as chronic kidney disease (CKD) or acute kidney injury (AKI), and infections may occur in conjunction with either. Pyelonephritis, a type of renal disease, typically results from bacterial infections ascending from the bladder to the kidneys. Recognizing the signs early can lead to prompt treatment and help avoid irreversible kidney damage.
Common Symptoms of Kidney Infection in Cats
- Increased thirst and urination (polydipsia and polyuria) – The kidneys lose the ability to concentrate urine, leading to excessive fluid loss and compensatory drinking.
- Loss of appetite – Infected or damaged kidneys produce uremic toxins that suppress appetite.
- Vomiting and diarrhea – As toxins accumulate in the blood, digestive upset becomes common.
- Lethargy and weakness – Energy levels drop as the body copes with internal imbalance.
- Bad breath (halitosis) – Often metallic or ammonia-like, resulting from uremia.
- Weight loss and muscle wasting – Chronic poor nutrition and systemic illness contribute to wasting.
- Dehydration – Despite increased fluid intake, cats may still become dehydrated due to fluid loss through urination.
- Behavioral changes – Cats might hide more, seem irritable, or show confusion as toxins affect their brain.
- Accidents outside the litter box – Often due to increased frequency or urgency of urination.
Progression of Symptoms
As the disease progresses, signs may become more severe. Symptoms of advanced kidney disease or infection might include:
- Mouth sores or oral ulcers
- Dry, unkempt coat
- Severe dehydration
- Pale gums (suggesting anemia)
- High blood pressure – Can lead to sudden blindness or seizures
- Confusion or disorientation
- Inability to walk in end-stage disease
Causes and Risk Factors
Kidney infections can result from:
- Bacterial infections ascending from the lower urinary tract
- Kidney stones or blockages that trap bacteria
- High blood pressure
- Genetic predisposition – Certain breeds like Persians or Abyssinians are more prone
- Chronic systemic diseases – Including thyroid disorders or cancer
- Exposure to toxins – Such as antifreeze or lilies
Diagnosis
Diagnosing kidney infection involves a series of tests:
- Blood work – Elevated BUN, creatinine, or SDMA levels indicate poor kidney function
- Urinalysis – Checks for concentration, presence of protein or white blood cells
- Urine culture – Identifies bacterial infections
- Imaging studies – Ultrasound can reveal kidney abnormalities
- Blood pressure measurement – High pressure is often associated
Treatment Options
Treatment aims to control the infection, reduce systemic symptoms, and support kidney function:
- Antibiotics – Target bacterial infection, guided by culture results
- Fluid therapy – IV or subcutaneous fluids help hydration and toxin removal
- Dietary management – Kidney-friendly food reduces metabolic strain
- Blood pressure medications – If hypertension is present
- Anti-nausea and appetite stimulant meds
Home Care Tips for Cats with Kidney Infection
- Provide plenty of fresh water and encourage drinking
- Feed wet, prescription renal diets if advised by your vet
- Observe for behavioral or appetite changes
- Maintain regular vet visits for monitoring
Prognosis
Early detection and treatment can resolve acute infections and slow the progression of chronic kidney issues. If left untreated, kidney infections can lead to irreversible damage or even kidney failure. With proper care, some cats can live for months or years after diagnosis with a reasonable quality of life.
Prevention
- Avoid toxins – Keep antifreeze, lilies, and unsuitable medications out of reach
- Early treatment of urinary tract infections to prevent ascension to kidneys
- Routine wellness exams with blood/urine screens, especially for older cats
By understanding the signs of a kidney infection and acting quickly, you can protect your feline companion’s health and well-being effectively.
