Addison’s disease in dogs is rare, affecting in most cases young and middle-aged dogs. Addison’s disease, known in scientific terms as hypoadrenocorticism, is manifested by a deficiency of the adrenal gland to produce corticosteroid hormones (cortisol and aldosterone). Aldosterone deficiency can lead to significant fluid loss, dehydration or weight loss. Clinical signs exist, but doctors generally do not diagnose them correctly, blaming trivial problems.
What is Addison’s disease in dogs?
Addison’s disease, also known as hypoadrenocorticism, is a condition that can have catastrophic repercussions for dogs, yet with adequate treatment, dogs with Addison’s disease can expect to live normally. When the adrenal glands fail to generate the hormones that they are in charge of in the body, Addison’s disease develops.
Steroids, notably aldosterone and cortisol, are the most significant hormones generated by the adrenal glands. These steroids regulate the internal organs and bodily systems of your dog. Your dog’s body will degenerate without them, leading to significant difficulties and even death.
Addison’s disease symptoms in dogs
Progressive Addison’s disease is hard to diagnose due to the wide range of symptoms associated with the disease. It’s known as the great imitator. In general, dogs with Addison’s disease may have recurring attacks of gastroenteritis, a weak appetite, sluggish weight loss, and an inability to adapt effectively to stress. It’s crucial to remember that Addison’s disease symptoms can come and go.
The body reacts strongly to a decrease in aldosterone production. It affects the kidneys by causing variations in sodium, chloride, and potassium levels in the blood. As a result, issues with the heart and circulatory system develop.
The other main steroid hormone impacted by Addison’s disease is cortisol, which is found in practically every essential tissue in the dog’s body. It controls glucose synthesis, metabolism, impacts fat and protein breakdown, regulates blood pressure, lowers inflammation, increases the development of red blood cells, and reduces stress.
The symptoms of Addison’s disease in dogs are varied, including:
– hair loss
– skin sensitivity
– loss of appetite
– weight loss
– abdominal pain
– Polydipsia (excessive thirst)
– Polyuria (abundant urine)
Although these symptoms are common to many pathologies, the veterinarian must make several investigations to avoid confusing Addison’s disease with other diseases. Administration of the correct treatment from the early stages of the disease will lead to a rapid recovery. At first the signs of the disease may be vague and non-specific, so the dog owner will not be able to detect a problem with the pet. The symptoms can gradually worsen, so we must always pay attention to any change in behaviour.
Other exceptional clinical signs are:
– megaesophagus – dogs suffering from this disease may have hypo-contractility that can lead to megaesophagus. Regurgitation is the common symptom.
– hypoglycaemia – hypoglycaemia is a common symptom of this disease. This is manifested by a state of weakness of the pet, ataxia, disorientation, as well as sudden falls or seizures.
– selective aldosterone deficiency – this deficiency is rarely seen in dogs presented to the veterinarian. An autopsy is needed to determine if it is a manifestation of Addison’s disease.
In most cases, the symptoms are caused by a deficiency of glucocorticoids and mineralocorticoid hormones.
Diagnosis of Addison’s disease in dogs
For a correct diagnosis of Addison’s disease in dogs, pet owners should consult a veterinarian to establish a correct diagnosis. We must keep in mind that the symptoms presented above can be misleading. Therefore, the animal’s health should not be ignored, as the symptoms may worsen immediately and the treatment will not be as effective.
The veterinarian before physical examinations and diagnostic tests (blood tests and urine tests), ultrasound and abdominal x-rays, will consult the medical history of the pet. It will look at whether the animal has suffered from gastrointestinal diseases or disorders in the past.
During an Addisonian crisis, Addison’s disease is frequently diagnosed. The condition reaches an acute stage in an Addisonian crisis, and dogs exhibit life-threatening symptoms such as shock and collapse.
After the dog has recovered from the crisis, vets do a battery of tests to figure out what caused the collapse and rule out alternative possibilities. They will most likely do blood tests to obtain a full blood count and biochemistry, as well as a urinalysis.
What tests are performed to confirm the diagnosis of Addison’s disease?
In order to detect Addison’s disease in dogs, a series of tests are needed to make a correct diagnosis. The veterinarian will first determine the basal level of cortisol to rule out hypoadrenocorticism. But this test is not enough to confirm the diagnosis, so a series of tests will have to be performed:
– ACTH stimulation test – is the first test to be performed in animals suspected of Addison’s disease, before establishing a long-term treatment. It is impossible to confirm Addison’s disease without stopping treatment for several weeks if treatment is started. This test is performed with synthetic ACTH. Sample samples are taken before and after one hour of ACTH to measure serum cortisol. Your veterinarian may also use dexamethasone to perform the ACTH stimulation test. It is not recommended to perform this test in all patients who present with vomiting or diarrhea. A biochemical and hematological profile, including electrolytes are indispensable. If several specific clinical signs occur: vomiting, diarrhea, weight loss, episodic collapse, etc., the ACTH test can be performed in parallel with routine laboratory tests. The diagnosis is confirmed if the concentration of post-ACTH cortisol is less than 2 μg / dL
– dosing of endogenous ACTH – for a correct differentiation between primary and secondary disease it is necessary to measure the concentration of endogenous ACTH. In primary hypoadrenocorticism the concentration of endogenous ACTH is high, and in the secondary form of the disease the concentration is low or very low.
– aldosterone dosing – this test is performed in the ACTH stimulation test (basal test and post-ACTH test). It is recommended in cases of dogs that show normal electrolyte values and a hypoadrenal response to the ACTH stimulation test.
Zycortal – treatment for Addison’s disease
Biotur offers you Zycortal, available on the Biotur Shop platform. Zycortal is an effective medicine against Addison’s disease in dogs.
Zycortal replaces only mineralocorticoid hormones. In dogs with a combined deficiency of glucocorticoids and mineralocorticoids, the administration of a glucocorticoid such as prednisolone is also recommended, according to standard texts.
Zycortal is intended for long-term administration at intervals and doses that depend on the individual response. The dose of Zycortal and concomitant glucocorticoid replacement therapy will be adjusted for each dog, depending on the clinical response and plasma Na⁺ and K⁺ levels normalization.