Feline Infectious Peritonitis: A Challenging Diagnostic and Therapeutic Labyrinth

Feline coronaviruses (FCoVs) are ubiquitous pathogens, exhibiting high prevalence across feline populations worldwide. Although the virulent mutated biotype feline infectious peritonitis virus (FIPV) is observed in only a small percentage of cats, it causes a systemic and often fatal disease. Diagnosis of feline infectious peritonitis (FIP) is challenging due to its non-specific clinical signs and the difficulty in differentiating between the two biotypes, feline enteric coronavirus (FECV) and FPIV. Currently, veterinarians rely on a combination of diagnostic methods, integrating laboratory tests, anamnesis and clinical signs to improve the diagnostic accuracy of FIP. Once considered untreatable, FIP now benefits from recent pharmacological advances that suggest promising therapeutic options, including antiviral drugs and immunomodulatory therapies. Despite these developments, the lack of an effective vaccine and definitive curative treatment highlights the need for continued research. This review provides a comprehensive analysis of the current literature on diagnostic and treatment approaches for FIP. The aim is to improve understanding of the available options and strategies for FIP to mitigate its severe consequences.