A challenging case: A collie with acute neurologic signs - Veterinary Medicine
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A challenging case: A collie with acute neurologic signs
This collie's condition has been historically identified in small-breed dogs. So after these clinicians narrowed down the potential causes of their patient's signs, the definitive diagnosis was surprising.



The overall incidence of hepatic microvascular dysplasia will likely increase with acceptance of diagnostic criteria, and the disease should be included in the differential diagnoses of animals presenting with signs of hepatic encephalopathy or gastrointestinal disease. Generally, the long-term prognosis for dogs with hepatic microvascular dysplasia appears to be better with medical management when compared with that for dogs with a portosystemic shunt.10 Dogs in which the disease is diagnosed at 1 year of age or less tend to remain in excellent or good condition with medical treatment.10 As has been described in the literature and in this case report, the prognosis for dogs with hepatic microvascular dysplasia diagnosed later in life (2 or 3 years of age) is guarded to poor because of medically intractable, recurrent clinical signs.10 Although neurologic signs often respond well to dietary management (i.e. low protein, highly digestible diets fed long-term), as demonstrated in this case, they, like the gastrointestinal manifestations previously reported in the literature, may have a variable response to treatment, with some patients having refractory clinical signs resulting in marked morbidity.10

Peter J. Lotsikas, DVM*
John H. Rossmeisl Jr., DVM, MS, DACVIM (internal medicine and neurology)
Department of Small Animal Clinical Sciences
Virginia-Maryland Regional College of Veterinary Medicine
Virginia Tech
Blacksburg, VA 24061

*Current address: Veterinary Teaching Hospital, College of Veterinary Medicine, Iowa State University, Ames, IA 50011-1250


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