FELINE INFECTIOUS PERITONITIS- LIKE CORONAVIRUS IN FERRETS Background Coronoviruses that infect ferrets are a severe acute respiratory syndrome (SARS) and an eqizootic catarrhal enteritis (ECE). SARS coronavirus has been experimentally transmitted to ferrets, but natural infections have not been reported in this species. Epizootic catarrhal enteritis causes diarrhea in young and adult ferrets. The infective agent is ferret enteric coronavirus (FECV). No lesions other than those affect- ing the gastrointestinal tract have been described. FECV is most closely related to feline coronavirus. Recently, a disease has been recognized in ferrets with gross, his- tologic, and immunohistochemical features that are similar to feline infectious perito- nitis (FIP). Objectives To report clinicopathologic features of a systemic coronavirus-associated disease resembling FIP in the domestic ferret. Procedure Twenty-three ferrets from Europe and the United States diagnosed with systemic pyogranulomatous inflammation resem- bling FIP were evaluated for clinicopath- ologic features. Results The average age of the ferrets at the time of diagnosis was 11 months, and the aver- age duration of clinical illness was 67 days. The disease was progressive in all cases. Common clinical findings were anorexia, weight loss, diarrhea, and large, palpable intra-abdominal masses. Hind limb pare- sis, central nervous system signs, vomiting, and dyspnea were less frequent. Typical hematologic findings were mild anemia, thrombocytopenia, and hyper- gammaglobulinemia. Whitish nodules were observed in the mesenteric adipose tissue and lymph nodes, visceral perito- neum, liver, kidneys, spleen, and lungs, among other tissues. One ferret had a serous abdominal effusion. Microscopic findings included pyogranulomatous inflammation involving especially the visceral peritoneum, mesenteric adipose tissue, liver, lungs, kidneys, lymph nodes, spleen, pancreas, adrenal glands, or blood vessels, or a combination of tissues. All cases were immunohistochemically posi- tive for coronavirus antigen using an FIP monoclonal antibody. Electron microscopic examination of inflammatory lesions iden- tified particles with coronavirus morpho- logy in the cytoplasm of macrophages. Partial sequencing of the coronavirus spike gene obtained from frozen tissue indicates that the virus is related to ferret enteric coronavirus. Author Conclusion A recent mutation or shift in the ferret coronavirus that causes ECE can cause FIP-like disease in ferrets. Inclusions Eleven figures, 1 table, 31 references. Editor Annotation Ferret enteric coronavirus is the proposed etiology for ECE, which generally results in mild to severe diarrhea.Younger ferrets typically recover with supportive therapy, while older, immunosuppressed animals often succumb. A number of researchers are now recognizing a systemic disease syndrome linked to a virus related to ferret enteric coronavirus. This disease resembles FIP, and is characterized by anorexia, weight loss, diarrhea, and large palpable intra-abdominal masses. Other less fre- quent findings reported are hind limb paresis and central nervous system disease. Gross findings include white nodules pre- sent in multiple tissues including liver, kidney, spleen, and lungs. Of 23 ferrets with FIP-like lesions submitted for exami- nation from Europe and the United States, all were positive for coronavirus antigen, and particles consistent with coronavirus were identified via electron microscopy of various tissues. The coronavirus initiating the lesions appears to be ferret enteric coronavirus. (AML) Garner MM, Ramsell K, Morera N, et al. Clini- copathologic features of a systemic coronavirus associated disease resembling feline infectious peritonitis in the domestic ferret (Mustela putorius).Vet Pathol 2008;45:236-246. American Journal ofVeterinary Research AustralianVeterinary Journal AustralianVeterinary Practitioner Avian Diseases BritishVeterinary Journal Canadian Journal ofVeterinary Research CanadianVeterinary Journal Journal of Avian Medicine and Surgery Journal of the American Animal Hospital Association Journal of the American Veterinary Medical Association Journal of Small Animal Practice Journal of Small Exotic Animal Medicine Journal ofVeterinary Dentistry Journal ofVeterinary Internal Medicine Journal ofVeterinary Pharmacology andTherapeutics Journal of Zoo andWildlife Medicine New ZealandVeterinary Journal Research inVeterinary Science Veterinary and Comparative Orthopaedics andTraumatology Veterinary Dermatology Veterinary Immunology and Immunopathology Veterinary Pathology Veterinary Radiology & Ultrasound Veterinary Record Veterinary Research Communications Veterinary Surgery .and more than 20 others PA G E 8A D V A N C E S Journals Monitored