Hypoadrenocorticism is primarily a disease of dogs and occurs only rarely in cats. This condition is heritable and most commonly affects dogs of 4 breeds:
• standard poodles,1
• Portuguese water dogs,2
• Nova Scotia duck tolling retrievers,3
• and bearded collies.
Other commonly affected breeds include
• West Highland white terriers,4,5
• Great Pyrenees,6 and
• wheaten terriers.4,5
Addison's disease is the common name for hypoadrenocorticism, a condition characterized by decreased hormone synthesis from the adrenal gland's outer section or cortex.
What are the adrenal glands, and what do they do?
The adrenal glands are tiny paired glands found near the kidneys. Each gland contains an outer cortex and an interior medulla. The glands generate two key hormones that govern a wide range of bodily activities and are required for survival. Cortisol is a stress hormone, and aldosterone regulates the amounts of sodium and potassium in the body. Sodium and potassium levels are essential for keeping the body's fluid equilibrium.
What causes Addison's disease?
The primary cause of Addison's disease in dogs is immune-mediated destruction of adrenal tissue. Trauma, infection, and cancer are less prevalent causes of adrenal gland injury. Addison's disease can also develop after therapy for Cushing's disease (hyperadrenocorticism), a condition in which too much cortisol and aldosterone are generated. If the drug used to treat Cushing's illness accidentally suppresses or destroys the adrenal gland, cortisol and aldosterone insufficiency may occur.
A secondary type of Addison's disease can be caused by a tumor or a malfunction in the pituitary gland, a key hormonal regulator in the brain. Secondary Addison's disease can develop if a dog has been treated with long-term steroids for any reason and then the medicine is abruptly discontinued. This last syndrome, known as iatrogenic hypoadrenocorticism, is typically short-term.
What are the clinical signs of hypoadrenocorticism?
Clinical symptoms of Addison's disease can usually be vague and non-specific, which means that no specific signs indicate a diagnosis. Addisonian individuals may exhibit lethargy, diarrhea, vomiting, increased thirst, increased urination, and unintentional weight loss. Intermittent shaking episodes are sometimes observed. The indications may appear and disappear.
Non-specific medical treatment, such as administering fluids or corticosteroids, tends to help momentarily, but the symptoms return quickly. If a pet exhibits recurring bouts of abrupt lethargy, diarrhea and vomiting, increased thirst and urination, or other non-specific sickness, Addison's disease should be investigated as underlying cause.
What constitutes an Addisonian crisis?
This illness can sometimes present with far more dangerous symptoms, such as abrupt weakness, severe vomiting and diarrhea, and even collapse. This is an Addisonian crisis, which is considered a medical emergency. Immediate hospitalization and supportive therapy are required.
How is Addison's disease diagnosed?
The diagnosis is based on your pet's medical history, including any medications, clinical indicators, and the results of routine blood and urine testing, including electrolyte imbalances. The ACTH-stimulation test is the most definitive way to diagnose Addison's disease. Cortisol levels are monitored before and after injecting a synthetic version of ACTH (see handout "Testing and Monitoring in Addison's Disease" for further information). Additional tests, such as basal cortisol levels, natural plasma ACTH, electrocardiogram (ECG), radiography (X-rays), or abdominal ultrasound, may be conducted to rule out any other causes of your pet's clinical indications. In rare cases, an MRI or CT scan may be required to diagnose a pituitary gland disease.
How is Addison's disease treated?
Once diagnosed, most dogs with Addison’s disease can be successfully treated.
Desoxycorticosterone pivalate; also known as DOCP (brand names: Percorten®-V or Zycortal®), is an injectable medication approved by the FDA for treatment of Addison’s disease in dogs. It is injected every 3–4 weeks, depending on the patient, and replaces the missing mineralocorticoid aldosterone. It is often supplemented by an oral glucocorticoid. With a little training, DOCP injections can be given at home.
DOCP is not for every dog, and some Addison’s patients do best on oral medications that replace both the mineralocorticoid and the glucocorticoid such as fludrocortisone (brand name Florinef®).
Your dog's diet and activity levels can often remain unchanged. The majority of dogs resume normal lives, even after an Addisonian crisis. Your veterinarian will discuss Addison’s treatment options with you and decide which therapy is best for your dog.
Информация по комментариям в разработке