Neuromuscular abnormalities associated with hypothyroidism and lymphocytic thyroiditis in three dogs.
Various degrees of persistent or paroxysmal paresis involving only the hindlimbs or all four limbs were observed in 3 dogs with hypothyroidism and lymphocytic thyroiditis. Clinical features included lethargy, obesity, alopecia, insidious and progressive paresis, hypotonia, and slow segmental reflexes in 2 dogs. Obesity, alopecia, paroxysmal paresis, and behavior change were observed in the third dog. Laboratory tests indicated that thyroid function was less than normal in all 3 dogs. Abnormal electromyographic potentials and slow motor nerve conduction velocities were found in each dog. Muscle biopsy specimen abnormalities included selective type-II myofiber atrophy in all dogs, whereas one dog had angular atrophy of type-I and type-II myofibers indicative of denervation. A substance that stained with para-aminosalicylic acid was observed within vacuoles of type-I myofibers in one dog. Lymphocytic thyroiditis characterized by lymphocytic infiltration of excised thyroid glands was observed in all dogs.
D000818:Animals; D001323:Autoantibodies / Q000032:analysis; D004283:Dog Diseases / Q000473:pathology / Q000503:physiopathology*; D004285:Dogs; D004576:Electromyography / Q000662:veterinary; D005260:Female; D007037:Hypothyroidism / Q000150:complications / Q000473:pathology / Q000503:physiopathology / Q000662:veterinary*; D008297:Male; D009431:Neural Conduction; D009468:Neuromuscular Diseases / Q000209:etiology / Q000662:veterinary*; D013961:Thyroid Gland / Q000276:immunology / Q000473:pathology; D013967:Thyroiditis, Autoimmune / Q000150:complications / Q000473:pathology / Q000503:physiopathology / Q000662:veterinary*
D001323:Autoantibodies; C006606:anti-thyroglobulin