If your cat is suddenly drinking more water, urinating frequently, or acting lethargic, they might be dealing with more than just a simple issue. Pyelonephritis (kidney infection) is a serious but treatable condition for many cats. Here is an overview of why it happens, how we diagnose it, and the best treatment and recovery options.
What Is Feline Pyelonephritis?
Pyelonephritis is a bacterial infection of the kidneys. While it can be difficult to diagnose, most cats respond well when the condition is identified and treated early. Left untreated, kidney infections can cause permanent kidney damage and, in severe cases, become life-threatening.
Cats at increased risk include those with:
- Kidney disease or diabetes
- Bladder stones or recurrent urinary tract infections
- Urinary tract abnormalities or obesity
Common Signs to Watch For
Symptoms can be subtle. If your cat is suffering from pyelonephritis, you might notice:
- Increased thirst and urination
- Lethargy and decreased appetite
- Weight loss
- Vomiting or fever
- Dehydration and general signs of illness
Emergency Warning: Patients with pyelonephritis can become very ill rapidly. If your cat is profoundly lethargic, vomiting continuously, completely refusing food, or showing severe signs of illness, seek immediate veterinary care. They may require immediate hospitalization and IV fluids.
How We Diagnose Pyelonephritis
To ensure an accurate diagnosis and target the specific bacteria, a combination of diagnostics is recommended:
- Urinalysis & Urine Culture: A sterile urine culture and sensitivity test is highly critical for identifying the exact causative bacteria and determining which antibiotics will be effective. (Kidney infections often do not respond to the basic antibiotics used for simple bladder infections).
- Comprehensive Blood Work (CBC & Chemistry): To evaluate kidney function and check for signs of systemic infection.
- Abdominal Ultrasound: To physically visualize the kidneys, assess for structural damage, and rule out concurrent disease.
- Blood Pressure Measurement: To check for hypertension related to kidney compromise.
Treatment Options
Treatment heavily relies on prolonged, targeted antibiotic therapy and supportive care.
1. Targeted Antibiotic Therapy
- Treatment consists of a fluoroquinolone antibiotic for 2 to 8 weeks. Thankfully, fluoroquinolones (Marbofloxacin or Pradofloxacin) are generally well tolerated and rarely cause side effects.
2. Supportive Medications & Fluid Therapy
- Anti-nausea medications (Cerenia®) and transdermal appetite stimulants (Mirataz® ) are often used for the first couple of days if your cat is experiencing nausea or poor appetite.
- Fluid Support: If kidney values show a mild increase, fluids administered under the skin (subcutaneous) for the first couple of days will suffice. If kidney values are moderately elevated and the cat is clinically sick, IV fluids and hospitalization will be needed.
Prognosis and Follow-Up Care
The prognosis is generally good when the condition is diagnosed and treated early. However, delayed diagnosis or recurrent infections can result in permanent kidney damage and the progression of chronic kidney disease. Based on concurrent disease processes and underlying kidney damage, we will formulate a long-term recheck plan.
This blog is for informational purposes only and is not intended to provide diagnostic or treatment guidance. If you have any concerns about your pet’s health, please contact Cascade Heights Veterinary Center directly by phone at 206-403-1108, email, or by scheduling an appointment. Medications, supplements, and prescription diets can be conveniently ordered through our online pharmacy.