Peer-reviewed veterinary case report
Perirenal bleeding linked to feline infectious peritonitis in cats
By Gauthier, Madeleine I et al.·Published in Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc·2025·Faculty of Veterinary Medicine, Canada·View original on PubMed →
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Original publication title: Perirenal hemorrhage associated with feline infectious peritonitis: a novel presentation of a classic disease.
- Species:
- cat
Plain-English summary
A 3-year-old cat with feline infectious peritonitis (FIP) was found to have bleeding around the kidneys, which is a rare complication of this disease. The cat showed signs of kidney issues and had fluid buildup in the abdomen. Upon examination, the vet discovered hemorrhages in the kidney area and surrounding tissues, which were linked to the FIP infection. While the exact cause of the bleeding isn't fully understood, it may be related to inflammation of the blood vessels caused by the virus. Treatment for FIP can be complex, but recognizing this unusual symptom can help vets provide better care.
People also search for: cat FIP symptoms · cat kidney bleeding treatment · feline infectious peritonitis signs
Abstract
Feline infectious peritonitis (FIP), caused by a mutated biotype of feline coronavirus (FCoV;,), is a significant disease of felids. We investigated perirenal hemorrhage, an unreported lesion in FIP, through a retrospective analysis of 51 immunohistochemistry-confirmed FIP cases submitted to the Diagnostic Services Unit (DSU; University of Calgary, Calgary, Alberta, Canada) between 2010 June 30 and 2024 June 30. Five cats had perirenal hemorrhage in the right retroperitoneal space; 4 had concurrent subcapsular renal hemorrhage; and 1 had sublumbar muscle hemorrhage and hemoabdomen. One case had additional hemorrhages in the brain and cervical spinal cord. Concurrent gross lesions typical of FIP included pyogranulomatous inflammation in various organs and protein-rich cavitary effusions. Histologic lesions typical of FIP (vasculitis and pyogranulomatous inflammation) were present in the kidneys and retroperitoneal fat of 4 cases, and in 3 cases, FCoV antigen was demonstrated in the regions of hemorrhage. The exact mechanism of this hemorrhage is unknown, but we speculate that vasculitis caused by FIP is the cause. Despite the relatively low prevalence of perirenal hemorrhage in this cohort, this lesion represents a unique, previously unreported manifestation of FIP that clinicians and pathologists should be aware of and consider in the differential diagnosis for fluid accumulation or space-occupying lesions in the retroperitoneum of cats.
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Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/40439038/