Myopathy associated with congenital fibre type disproportion in a young dog.
A 4-month-old, female collie-cross dog was presented for evaluation of slowly progressive weakness, exercise intolerance and muscle atrophy. Neurological examination and electrodiagnostic testing were consistent with a generalized myopathy or, less likely, an axonal polyneuropathy. Muscle biopsy samples revealed marked variability in myofibre size with scattered or clustered atrophic or hypotrophic type 1 fibres. Type 1 fibres were 65% smaller than type 2A fibres and the percentage of type 1 fibres exceeded reference values for both limb muscles examined. On the basis of the clinical evaluation, pathological changes and the absence of another defined congenital or acquired myopathy, a diagnosis of a myopathy associated with congenital fibre type disproportion was made. Three months later the animal was humanely euthanized because of worsening clinical signs.
Southern Counties Veterinary Specialists, Ringwood, Hampshire BH24 3JW, UK. sergiorodenas5@yahoo.com
S
S
Rodenas
L T
LT
Guo
G D
GD
Shelton
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D005260:Female; D018485:Muscle Fibers, Skeletal / Q000201:enzymology / Q000473:pathology*; D018482:Muscle, Skeletal / Q000473:pathology / Q000502:physiology; D009135:Muscular Diseases / Q000151:congenital / Q000175:diagnosis*; D012016:Reference Values; D012038:Regeneration
D000251:Adenosine Triphosphatases