Immune-Mediated Polyarthritis in Dogs: Welfare Guide

Key Welfare Considerations

• IMPA involves immune complex deposition or direct immune attack on multiple joints simultaneously.
• Clinical signs include stilted gait, joint swelling, fever, lethargy, and marked welfare pain on joint manipulation.
• Type I (idiopathic) IMPA is most common — no underlying cause is identified and immunosuppression is curative.
• Secondary IMPA can be triggered by infections, neoplasia, and drug reactions — welfare treatment targets underlying cause.
• Joint tap for cytology is the definitive diagnostic test — inflammatory cells without bacteria confirm IMPA welfare diagnosis.
• Prednisolone at immunosuppressive doses is the primary welfare treatment for idiopathic IMPA.
• Response to prednisolone is typically rapid and dramatic — welfare improvement within 1-2 weeks is expected.
• Azathioprine or leflunomide are added for steroid-sparing welfare management in refractory cases.
• Welfare monitoring includes joint assessment, complete blood count, and biochemistry during immunosuppression.
• Prednisolone side effects including polyuria, polydipsia, and weight gain affect welfare quality of life.
• Gradual dose tapering over 3-6 months maintains welfare remission while minimising side effects.
• Relapse occurs in a proportion of dogs — welfare monitoring enables early retreatment before severe deterioration.
• Rest during acute flares reduces joint damage welfare burden and supports recovery.
• Physiotherapy during recovery maintains muscle mass and joint range of motion for welfare.
• Long-term welfare outlook for Type I IMPA is excellent — many dogs achieve sustained remission.