Vet. Pathol. 23:528-531 (1986) Polyneuropathy and Hormone Profiles in a Chow Puppy with Hypoplasia of the Islets of Langerhans

Spontaneous diabetes mellitus in dogs occurs in 0.125% to 0.5 % of patients presented to veterinary hospitals, usually in obese females aged 4 to 14 years with a peak incidence at 8 to 9 year^.^.^ ' Spontaneous diabetes mellitus in dogs under one year of age is less commonly seen, comprising fewer than 1.5 % of all canine Diabetes in young dogs is usually associated with degeneration or atrophy of both the endocrine and exocrine pancreas. 1,3,19,26,27 Congenital absence or hypoplasia of only the endocrine pancreas has been re-ported in dogs and in p e ~ p l e. ~ ~ J ~ J *- ~ ~ In diabetic keeshond dogs aplasia of beta cells in the islets of Langerhans with persistence of the solitary beta cell population is evident at birth. This report describes the clinical, biochemical, and pathologic findings in a chow puppy with spontaneous ju-venile diabetes mellitus. A 4-month-old, 5 kg, female chow was presented to the Auburn University Small Animal Clinic for polydipsia, poly-uria, and rear limb ataxia. Diabetes mellitus had been di-agnosed 10 days previously based on glycosuria, ketonuria, and fasting hyperglycemia (406 mg/dl), which was relieved by treatment with NPH insulin (1 0 to 12 units once a day, subcutaneous). Clinical and neurologic examination revealed bilateral cataracts, a moderate degree of generalized appen-dicular muscle atrophy, pelvic limb paresis, and depressed pelvic limb postural reactions. Spinal reflexes were intact. There was no evidence of physical injury which could have caused the pelvic limb paresis. Electrophysiologic studies performed on muscles and nerves on the right side of the body revealed reduced insertion potentials of thoracic and pelvic limb appendicular muscles. Nerve conduction velocity was depressed in the ulnar nerve (44 m/sec) and was low normal in the sciatic-tibia1 nerves (6 1.5 m/sec). The complete blood count, serum protein, electrolytes, he-patic enzymes, amylase, and blood urea nitrogen were nor-mal for the age of the dog. The blood glucose was elevated (257 mg/dl) 6 hours after eating and insulin treatment (1