Pathological features of polyneuropathy in three dogs

Area of Science:

• Veterinary Neurology
• Comparative Pathology

Background:

• Canine polyneuropathy (CPN) is a debilitating neurological disorder affecting peripheral nerves.
• Etiologies for CPN are diverse, including infectious, immune-mediated, hereditary, endocrine, neoplastic, and toxic causes.
• Clinical signs alone often fail to pinpoint the specific cause of CPN.

Observation:

• Three cases of canine polyneuropathy were examined: a Border Collie (Dog 1), a Chihuahua (Dog 2), and a Beagle (Dog 3).
• Clinical signs included hindlimb ataxia and sensory loss (Dog 1), forelimb paralysis and pain (Dog 2), and paddling gait with hypothyroidism (Dog 3).
• Histopathology revealed distinct lesions: axonal swelling and demyelination (Dog 1), giant axons (Dog 2), and atrophic axons with edema (Dog 3).

Findings:

• Dog 1 exhibited axonal swelling and pale myelin, suggestive of a hereditary polyneuropathy.
• Dog 2 presented with giant axons, mimicking giant axonal neuropathy, also suspected to be hereditary.
• Dog 3 showed atrophic axons and interstitial edema, consistent with hypothyroidism-associated polyneuropathy.

Implications:

• The study demonstrates unique pathological features in canine polyneuropathy cases, correlating with clinical presentations.
• Distinct histopathological findings suggest different underlying pathogeneses for peripheral nerve dysfunction in dogs.
• Understanding these pathological variations is crucial for accurate diagnosis and targeted treatment of canine polyneuropathy.