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Published on: November 4, 2015
Case Report: Mineralized Pulmonary Artery Thrombi in Two Dogs Treated for Meningoencephalitis of Unknown Origin
Suzanne Rosen1, Leontine Benedicenti1, Scott Petesch1
1School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States.
Abstract:
Meningoencephalitis of unknown origin (MUO) is a relatively common and very serious canine neurologic condition, which is typically associated with a poor long term prognosis despite treatment. This case series chronicles two dogs diagnosed with MUO who were treated with long term corticosteroids and cytosine arabinoside and lived well-beyond the typical survival time for this condition. Both eventually succumbed to respiratory signs associated with mineralized thrombi in their pulmonary arteries. Adverse effects from the two drugs used for treatment are reviewed in order to propose a possible mechanism to explain how long term use of these medications could result in such a phenomenon.
Insights
Meningoencephalitis of unknown origin (MUO) in dogs can be fatal, but long-term treatment with corticosteroids and cytosine arabinoside improved survival. However, dogs later developed fatal respiratory issues potentially linked to medication side effects.
Area of Science:
- Veterinary Neurology
- Immunosuppressive Therapy
- Canine Pathology
Background:
- Meningoencephalitis of unknown origin (MUO) is a severe neurological disorder in dogs with a typically poor prognosis.
- Standard treatments often yield limited long-term success.
Observation:
- This case series describes two dogs with MUO treated with long-term corticosteroids and cytosine arabinoside.
- Both dogs survived significantly longer than expected for this condition.
Findings:
- The dogs ultimately died from respiratory failure due to pulmonary arterial mineralization.
- This suggests a potential link between long-term immunosuppressive drug use and thromboembolic events.
Implications:
- The findings prompt a review of adverse effects associated with long-term corticosteroid and cytosine arabinoside therapy in dogs.
- Understanding these mechanisms may lead to improved management strategies for canine MUO and prevent fatal complications.
