Characterisation of Lafora-like bodies and other polyglucosan bodies in two aged dogs with neurological disease

Canine Lafora disease is a genetic disorder of carbohydrate metabolism characterised by neurological signs and accumulation of a type of polyglucosan body (PGB), the Lafora body (LB), in the brain and other organs. Normal canine ageing is associated with accumulation of PGBs in the brain, especially those corresponding to corpora amylacea (CA). In this study, two aged dogs that presented with progressive tremors, ataxia and paraplegia had abundant PGBs throughout the brain, mainly in the hypothalamus and molecular layer of the cerebellum. Hypothalamic and cerebellar PGBs from both cases had lower alcohol-resistant metachromasia than CA when stained with toluidine blue. Immunohistochemical studies of these PGBs against neurone-specific enolase (NSE), glial fibrillary acid protein (GFAP), 200 KDa neurofilaments, S-100, Tau, ubiquitin and heat shock proteins 25 and 70, showed some differences to CA.