Pyogranulomatous panophthalmitis with systemic coronavirus disease in a domestic ferret (Mustela putorius furo).

A 15-month-old spayed female ferret (Mustela putorius furo) presented for lethargy and weight loss of 2 weeks duration. Upon physical examination, a 2-mm-diameter focal area of opacity was noted in the left cornea. In addition, the ferret was quiet, in poor body condition, and dehydrated. A complete blood count and plasma biochemistry revealed a severe nonregenerative anemia, azotemia, hyperproteinemia, hypoalbuminemia, and mild hyperphosphatemia and hyperchloremia. Urinalysis revealed hyposthenuria. Whole body radiographs showed multifocal thoracic nodular disease, splenomegaly, and renomegaly. Abdominal ultrasonography confirmed bilaterally enlarged kidneys, hypoechoic liver and spleen, and a caudal abdominal hypoechoic mobile nodule. The ferret was humanely euthanized, and a postmortem examination with subsequent histopathology showed multifocal necrotizing pyogranulomas in the lung, spleen, kidneys, mesenteric lymph nodes, and serosa of the duodenum. Pyogranulomatous panophthalmitis was diagnosed in the left eye. The multisystemic granulomatous lesions were suggestive of ferret systemic coronavirus (FRSCV). The presence of coronavirus in the left eye was confirmed by positive immunohistochemistry. Reverse transcriptase polymerase chain reaction (RT-PCR) on formalin fixed paraffin embedded tissue from the lung, spleen, and kidney was negative for FRSCV and positive for ferret enteric coronavirus (FRECV). Systemic coronavirus disease in ferrets closely resembles feline infectious peritonitis (FIP) in domestic cats, which can manifest with anterior uveitis, chorioretinitis, optic neuritis, and retinal detachment. To the authors' knowledge, this is the first report of ocular lesions in a ferret with systemic coronavirus disease, suggesting that ferrets presented with similar ocular lesions should also be evaluated for evidence of coronavirus infection.