Disseminated, histologically confirmed Cryptococcus spp infection in a domestic ferret

A 4-year-old castrated male domestic ferret from central Massachusetts was evaluated for weight loss over a 1.5-month period and for 2 days of retching, diarrhea, and signs of lethargy. It had been housed indoors, with 2 other ferrets, 2 cats, and humans that lacked signs or symptoms of disease.

Physical examination revealed a thin body condition, tachypnea, an increase in respiratory effort, and retching. Splenomegaly was detected during abdominal palpation. Clinicopathologic analysis revealed lymphopenia, lactic acidosis, hypoglycemia, hypocalcemia, hypoalbuminemia, and hyperglobulinemia. A pulmonary bronchointerstitial pattern was evident on radiographs, and abdominal ultrasonography revealed a suspected pancreatic mass and mesenteric lymphadenopathy.

After 2 weeks of medical treatment and once clinical signs resolved, an exploratory laparotomy was performed and a lymph node biopsy specimen was collected. Histologic evaluation of the specimen revealed Cryptococcus-like organisms. Antifungal treatment was initiated with itraconazole (PO) and amphotericin B (IV). The ferret died after 2 days of treatment. A full necropsy was performed, revealing multicentric cryptococcosis affecting the lungs, brain, spleen, and multiple lymph nodes. Paraffin-embedded, formalin-fixed lung tissue was submitted for DNA extraction, and the organism was identified as Cryptococcus neoformans var grubii.

To the authors' knowledge, this is the first report of disseminated cryptococcosis in a North American ferret. This case is unique in that the ferret lived indoors, in a geographic region in which reports of cryptococcosis are rare. The genotyping technique used to identify the Cryptococcus strain can aid in better understanding the epidemiology of cryptococcosis.