Understanding the Rivalta Test: A Key Diagnostic Tool for Detecting Wet FIP in Cats
- CUREFIP.COM
- Oct 16
- 4 min read
Feline Infectious Peritonitis (FIP) is one of the most devastating viral diseases affecting cats. For years, it was considered untreatable — but now, thanks to modern antiviral therapy such as GS-441524, many cats across Europe are surviving and recovering fully under the CureFIP protocol.
Among the various types of FIP, wet (effusive) FIP is the most common. It’s typically identified through clinical symptoms like abdominal swelling and breathing difficulties, caused by fluid buildup inside the body.
Veterinarians across Europe often use a simple but highly reliable diagnostic method known as the Rivalta Test to help confirm suspected cases of wet FIP.
What Is the Rivalta Test?
The Rivalta Test is a diagnostic tool first developed in 1900 by an Italian scientist, Rivalta. It helps determine whether the fluid (effusion) found inside a cat’s abdomen or chest is likely to be caused by FIP or by another medical condition such as infection, liver disease, or cancer.
In European veterinary clinics, this test is often performed as an initial screening tool before moving on to advanced diagnostics like PCR testing, FCoV antibody testing, or ultrasound imaging.
How the Rivalta Test Works
The Rivalta Test is simple and cost-effective:
A test tube is filled with distilled water and a few drops of acetic acid (vinegar).
A drop of the cat’s effusion fluid is added.
The result depends on how the drop behaves:
Positive: The drop remains intact or sinks slowly — suggesting FIP.
Negative: The drop dissolves quickly and the liquid remains clear — suggesting another cause.
A positive Rivalta Test supports a likely diagnosis of FIP, but confirmation through additional tests is still required.
Accuracy of the Rivalta Test
The Rivalta Test remains one of the most reliable quick-screening tools for wet FIP, with:
Positive predictive value: ~86%
Negative predictive value: up to 96%
In simple terms:
A negative result makes FIP unlikely.
A positive result increases the likelihood and should be followed by:
Blood tests (biochemistry, protein levels, globulin ratio)
Feline coronavirus (FCoV) antibody or PCR testing
Imaging (ultrasound or X-ray)
European vets often use these combined results to make a confident FIP diagnosis before starting treatment.
How the Rivalta Test Relates to Wet FIP Symptoms in Cats
One of the most visible signs of wet FIP is a bloated or enlarged abdomen, caused by fluid buildup in the peritoneal cavity. This can also occur in the chest, causing laboured breathing or panting.
While other diseases — such as bacterial infections, liver disease, heart issues, or parasitic infestations — can also cause abdominal swelling, FIP should be suspected if your cat also shows:
Persistent fever
Lethargy or weakness
Weight loss
Reduced appetite
The Rivalta Test helps veterinarians quickly assess whether the fluid’s composition matches that typically seen in FIP, allowing early treatment to begin.
Treatment for Wet FIP in Europe
Until recently, a diagnosis of FIP meant there was little hope. But today, antiviral treatment using GS-441524, developed under the CureFIP protocol, has changed that reality.
Across Europe, cat owners and vets are now using GS-441524 under compassionate-use or special import permissions, depending on national regulations. While the medication is not yet licensed in all EU countries, many veterinarians have seen remarkable recoveries.
How GS-441524 Works:
Blocks replication of the FIP virus (a mutated form of feline coronavirus).
Reduces inflammation and fluid accumulation.
Helps the body gradually reabsorb excess effusion.
Restores appetite, energy, and normal behaviour.
For cats with pleural effusion (fluid in the chest), vets may perform a thoracocentesis to remove the fluid completely and ease breathing.For abdominal effusion (ascites), only partial drainage — usually 20–30% — is recommended per session to prevent sudden drops in blood pressure or shock.
The CureFIP treatment protocol provides clear dosing, duration, and monitoring guidance for European vets and cat owners.
When to Visit the Vet
If you notice any of these signs in your cat, don’t delay:
Bloated or enlarged belly
Rapid or laboured breathing
Fever that doesn’t go down
Loss of appetite or thirst
Unexplained weakness
Early diagnosis and antiviral treatment offer the best chance of success.
Contact your local veterinarian or reach out to CureFIP Support for guidance on diagnosis and treatment access.
👉 Learn more: https://www.curefip.com
Frequently Asked Questions (FAQ)
1. What is Wet FIP in cats?
Wet FIP is a form of Feline Infectious Peritonitis that causes fluid buildup in the cat’s abdomen or chest, leading to swelling and breathing difficulty.
2. How is Wet FIP diagnosed?
Through a combination of the Rivalta Test, blood tests, imaging, and FCoV antibody or PCR testing.
3. Is FIP curable?
Yes. With GS-441524 antiviral therapy following the CureFIP protocol, many cats recover fully and live normal lives.
4. Can I get GS-441524 legally in Europe?
Availability varies by country. In some regions, it can be obtained through compassionate use, prescription import, or CureFIP-authorized channels.
5. Is FIP contagious to humans or other pets?
No. FIP itself isn’t contagious to humans, but the underlying feline coronavirus (FCoV) can spread between cats.
6. How effective is the Rivalta Test?
It’s around 86% accurate for positive results and 96% for negatives. It’s an excellent first-line screening tool.
7. What’s the success rate of CureFIP treatment in Europe?
Over 90% of cats treated following the CureFIP GS-441524 protocol recover fully when diagnosed and treated early.
Final Note for European Cat Owners
If your cat shows sudden abdominal swelling, fever, or difficulty breathing, don’t wait — ask your vet about performing a Rivalta Test. It’s simple, affordable, and could make all the difference.
FIP is no longer a death sentence. Thanks to CureFIP and GS-441524 therapy, thousands of cats across Europe have already recovered and returned to happy, healthy lives.
👉 Learn more about treatment, access, and recovery stories at www.curefip.com