Marie E. Kerl, DVM, DACVIM, DACVECC

Hyperadrenocorticism (HAC) (commonly called Cushings disease) is a commonly diagnosed endocrinopathy in dogs which is caused by persistently high cortisol levels in circulation.

The hormones that dictate calcium regulation include parathyroid hormone (PTH), active vitamin D (1,25 dihydroxycholecalciferol), and calcitonin. Parathyroid hormone functions include mobilization of Ca++ from the bone, and promotion of vitamin D conversion from 25 (OH) cholecalciferol to 1,25-dihydroxycholecalciferol (active vitamin D).

Hypoadrenocorticism (Addisons disease) remains challenging to recognize due to the variety of clinical signs that mimic other diseases.

Diabetes mellitus is the condition of hyperglycemia (high blood glucose) and glucosuria (glucose in the urine) caused by absence of the hormone insulin, or failure of the cells of the body to be able to respond to insulin.

The kidneys are the only organ system within the body containing two sets of capillary beds with different functions. The glomerulus consists of 4-8 lobules containing glomerular capillaries with mesangium providing structural support to hold the capillaries together.

The definition of kidney disease includes any structural or functional change of the kidneys. The kidneys are uniquely susceptible to injury due to the large quantity of blood filtered for each cardiac cycle (20-25% of cardiac output), regional differences in blood supply within the kidney, and a high rate of metabolic activity of renal tubular cells.

Hyperadrenocorticism (HAC) is a commonly diagnosed endocrinopathy in dogs which is caused by persistently high cortisol levels in circulation. Diagnosis and treatment may not be straightforward, and successful management depends upon appropriate evaluation of clinical signs, selection and interpretation of diagnostic tests, and administration and monitoring of therapy.