Clinical diabetes mellitus in association with diestrus-induced acromegaly in 2 bitches

Two intact bitches aged 9 and 11 years were referred due to chronic polyuria, polydipsia, vomiting, anorexia and progressive lethargy. On clinical examination, signs of tissue overgrowth (large paws, widened interdental space, pharyngeal stridor) were noticed. Diabetes mellitus (DM) was diagnosed in one dog (case 1) and diabetic ketoacidosis (DKA) in the other (case 2). There were increased IGF-1 values suggestive of hypersomatotropism. Progesterone values and pathological findings of the ovaries and uterus indicated diestrus. Diagnosis of diestrus-induced hypersomatotropism was made and ovariohysterectomy was performed in both dogs. Dog 1 also had multiple mammary neoplasms treated with bilateral mastectomy. Treatment resulted in diabetic remission in case 1 and improved glycaemic control in case 2. Overall, diestrus-induced hypersomatotropism is rare but should be considered in any intact diabetic bitch with acromegalic features. Ovariohysterectomy is recommended and associated with a fair to good prognosis.