Cat Feline Infectious Peritonitis Pathophysiology

Understanding FIP pathophysiology helps owners recognize early signs and access life-saving treatment before the disease becomes too advanced to manage effectively.

Key Facts

FIP develops when feline coronavirus mutates to a virulent biotype within an individual cat
The mutation causes macrophage infection and vasculitis driving wet or dry disease forms
Wet FIP causes protein-rich effusions in the abdomen or chest within weeks of onset
Dry FIP causes granulomas in organs including brain, eyes, liver, and kidneys
Early diagnosis using PCR on effusion fluid plus clinical presentation enables treatment before advanced disease

Welfare Considerations

Cats developing FIP deteriorate rapidly without treatment - the wet form progresses to incapacitating fluid accumulation within weeks. The dry form may cause neurological signs including seizures, ataxia, and blindness as brain granulomas enlarge. Antiviral treatment with GS-441524 requires early initiation - cats diagnosed at early disease stages have significantly better response rates and achieve sustained remission more reliably. Owner recognition of early signs (weight loss, fever, poor coat) enables the timely diagnosis that saves lives.

What You Can Do

Learn the early warning signs of FIP including recurrent fever, weight loss, and abdominal distension
Ask your vet about PCR testing on any unexplained effusions
Contact FIP treatment assistance organizations immediately if diagnosis is confirmed
Join FIP Warriors or similar communities for peer support and treatment guidance