Diagnosis and Treatment of Histoplasmosis in a Group of Four Domestic Ferrets (Mustela Putorius Furo) and a Review of Histoplasmosis

• Published in: Journal of exotic pet medicine 2019-04, Vol.29, p.194-201
• Main Authors: Greenacre, Cheryl B., Dowling, Matthew, Nobrega-Lee, Michelle
• Format: Article
• Language: English
• Subjects: ferret; fungal; Histoplasma capsulatum; histoplasmosis
• ISSN: 1557-5063; 1931-6283
• DOI: 10.1053/j.jepm.2018.11.008

A 1.5-year-old castrated male domestic ferret (Mustela putorius furo) was referred for profound depression, dyspnea, and seizures with a 5 months history of chronic, yellowish-green diarrhea that was minimally responsive to typical therapies for helicobacteriosis. An exploratory laparotomy and liver biopsy had been performed 12 days prior to presentation showing only a tan-colored liver. Three other ferrets in the household also had chronic, intermittent soft stools. On presentation a CBC, radiographs and ultrasound showed a thrombocytopenia (10,000), a moderate diffuse bronchial pattern to all lung lobes, and a hepato-splenomegaly with normal echogenicity. Results of special staining of the liver biopsy showed evidence of Histoplasma spp. fungal organisms. The ferret was euthanized after it did not respond to treatment. Necropsy showed Histoplasma sp. organisms in the liver, lung, spleen, multiple lymph nodes, bone marrow, and brain. A serum AGID for antibodies to Histoplasma spp. was negative in this ferret and its 3 cage mates, but all four were positive on the urine antigen test to Histoplasma spp., the test of choice. The other 3 ferrets responded well to itraconazole, the drug of choice, based on resolution of clinical signs and subsequent negative urine antigen tests. Histoplasmosis is a differential for ferrets with chronic diarrhea.