Hypertrophic neuropathy

From Dog

Hypertrophic neuropathy (canine inherited hypertrophic neuropathy) is a rare genetic disease of the Tibetan Mastiff characterized by neonatal neurological disease due to demyelination of peripheral Schwann nerve cells[1].

A similar condition has been described in the German Shepherd with peripheral neuropathy and progressive muscular weakness[2].

Affected pups usually present with progressive weakness and hyporeflexia at weaning[3], and subsequently develop limb contractures[4].

Most do not show clinical evidence of cranial nerve dysfunction[5].

Histopathological examination of affected nerves in dogs has shown widespread demyelination and primitive onion bulb formation with relatively little degeneration of axons.

Myelin changes are most striking in the cytoplasmic regions of the sheaths and consisted of separations at the major dense lines, anomalous incisure patterns, and marked filamentous accumulations in the inner spirals and adaxonal cytoplasm[6].

A differential diagnosis includes other causes of peripheral neuropathy and polyneuropathy such as degenerative myelopathy in Pembroke Welsh Corgis and Boxers, peripheral nerve hyperexcitability syndrome in Jack Russell terriers.

There is no known treatment for this condition and affected pups usually require euthanasia.

References

  1. Cooper BJ et al (1984) Defective Schwann cell function in canine inherited hypertrophic neuropathy. Acta Neuropathol 63(1):51-56
  2. Furuoka H et al (1992) Peripheral neuropathy in German shepherd dogs. J Comp Pathol 107(2):169-177
  3. Cummings JF et al (1981) Canine inherited hypertrophic neuropathy. Acta Neuropathol 53(2):137-143
  4. Cooper BJ et al (1984) Canine inherited hypertrophic neuropathy: clinical and electrodiagnostic studies. Am J Vet Res 45(6):1172-1177
  5. Cummings JF & de Lahunta A (1974) Hypertrophic neuropathy in a dog. Acta Neuropathol 29(4):325-336
  6. Sponenberg DP & deLahunta A (1981) Hereditary hypertrophic neuropathy in Tibetan Mastiff dogs. J Hered 72(4):287