Feline Infectious Peritonitis (FIP): Understanding This Devastating Disease
FIP is a complex disease caused by feline coronavirus. Recent treatment breakthroughs have given new hope to affected cats.
Feline infectious peritonitis (FIP) is a serious and often fatal disease caused by a mutation of feline coronavirus (FCoV). While most cats infected with FCoV remain healthy, in a small percentage the virus mutates into the FIP-causing form. Excitingly, new antiviral treatments have dramatically improved survival rates.
Key Points
- FIP is caused by a mutation of common feline coronavirus
- Most cats with coronavirus never develop FIP
- Young cats and purebreds are at higher risk
- Two forms: 'wet' (fluid accumulation) and 'dry' (granulomas)
- New antiviral treatments (GS-441524) have transformed outcomes
- Early diagnosis and treatment are critical
Understanding FIP
Feline coronavirus is extremely common — most cats in multi-cat environments have been exposed. In most cats, it causes mild or no symptoms. But in a small percentage (estimated 5-10%), the virus mutates inside the cat's body into a form that causes FIP. The mutated virus attacks macrophages (immune cells) and causes widespread inflammation.
Two Forms of FIP
Effusive (wet) form: fluid accumulates in the abdomen (swollen belly) or chest (difficulty breathing). Non-effusive (dry) form: granulomas (inflammatory masses) form in organs like the kidneys, liver, eyes, and brain. Both forms cause fever, weight loss, lethargy, and loss of appetite. The dry form is harder to diagnose because symptoms vary based on which organs are affected.
Diagnosis and Treatment
FIP diagnosis is challenging and often requires multiple tests: blood work (elevated proteins, low albumin, high globulin), fluid analysis, and sometimes PCR or histopathology. The big news: antiviral treatment with GS-441524 has transformed FIP from a death sentence to a treatable disease, with cure rates of 80-90% in many studies.
Prevention
Since FIP develops from a common coronavirus, preventing exposure is difficult in multi-cat environments. Reducing stress, maintaining good hygiene (clean litter boxes frequently), and avoiding overcrowding can help. A nasal vaccine exists but is not widely used due to limited effectiveness. Keeping cats in small groups and minimizing stress is the best approach.
When to See a Vet Immediately
- Progressive swelling of the abdomen
- Difficulty breathing (fluid in chest)
- Persistent fever not responding to antibiotics
- Unexplained weight loss
- Eye inflammation or neurological signs
- Lethargy and loss of appetite in a young cat
How RVC Can Help
RVC's team can diagnose FIP through comprehensive testing and guide you through antiviral treatment options. With new treatments, many cats can be cured. Call +853 6677 6611.
This article is for educational purposes only and does not replace professional veterinary advice. If your pet is showing any symptoms, please contact Royal Veterinary Center immediately at +853 6677 6611.