Leeching as initial treatment in a cat with polycythaemia vera
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Published on: September 18, 2013
C S Nett1, P Arnold, T M Glaus
1Clinic for Small Animal Internal Medicine, University of Zurich, Switzerland.
Insights
Leeches offer a simple, effective initial treatment for feline polycythaemia vera when phlebotomy is not feasible. This non-invasive method successfully reduced packed cell volume (PCV) in a cat with this rare blood disorder.
Area of Science:
- Veterinary Medicine
- Hematology
Background:
- Polycythaemia vera is a rare myeloproliferative neoplasm characterized by excessive red blood cell production.
- Diagnosis in veterinary patients requires excluding secondary causes of erythrocytosis.
Observation:
- A three-year-old domestic shorthaired cat presented with seizures and severe erythrocytosis (PCV 79%).
- Initial treatment with phlebotomy was not possible due to hyperviscosity.
Findings:
- A novel approach using four leeches was employed for initial bloodletting.
- Leech therapy reduced the packed cell volume (PCV) from 79% to 64% within hours, and to 56% after 24 hours.
- Long-term management was achieved with hydroxyurea and intermittent phlebotomy.
Implications:
- Leech therapy presents a viable, non-invasive alternative for initial management of polycythaemia vera in cats when phlebotomy is contraindicated.
- This case highlights an innovative therapeutic option for a rare feline hematological disorder.
Abstract:
Polycythaemia vera was diagnosed in a three-year-old domestic shorthaired cat referred because of seizures and a high packed cell volume (PCV). Laboratory examination revealed severe erythrocytosis (PCV 79 per cent). Diagnosis was reached by excluding causes for relative and secondary absolute polycythaemia. As phlebotomy proved impossible for initial treatment due to hyperviscosity, four leeches were used to suck blood and the PCV was consequently reduced to 64 per cent. A further 24 hours later, when bleeding at the sites of sucking had stopped, the PCV was 56 per cent. Long-term management of the condition was achieved with hydroxyurea (100 mg/cat once daily) and intermittent phlebotomy. Initial treatment using leeches in cases of polycythaemia vera is a simple, non-invasive, well tolerated and effective method where phlebotomy is not possible.
