Canine Cushing's Disease Overview
As pet owners, we do our best to keep our dogs healthy and happy. But as they age, some dogs may develop chronic health conditions that require extra care and attention. Canine Cushing’s Disease, also known as hyperadrenocorticism, is one of these conditions, caused by an overproduction of the hormone cortisol. This hormonal imbalance can affect a dog’s well-being in many ways, so understanding its symptoms, causes, and treatment options is essential to provide your dog with the best quality of life.
In this guide, we’ll dive into what Canine Cushing’s Disease is, its symptoms, treatment options, and tips for managing it.
What is Canine Cushing's Disease?
Cushing’s Disease in dogs is a hormonal disorder that results from the overproduction of cortisol, often referred to as the “stress hormone.” Cortisol helps regulate many essential functions, including blood sugar levels, immune response, and metabolism. However, when cortisol levels are consistently high, it can cause numerous health issues and affect a dog’s overall quality of life.
Types of Cushing's Disease in Dogs
There are three primary types of Cushing’s Disease in dogs:
- Pituitary-Dependent Cushing's Disease (PDH): This is the most common form, accounting for about 80-85% of cases. It occurs when a small tumour on the pituitary gland triggers excessive cortisol production.
- Adrenal-Dependent Cushing's Disease (ADH): This type, responsible for about 15-20% of cases, results from a tumour on one or both adrenal glands, leading to overproduction of cortisol.
- Iatrogenic Cushing's Disease: This type is caused by long-term use of corticosteroid medications, often prescribed for conditions like allergies or arthritis. Stopping the medication under a vet’s guidance can sometimes resolve this form of Cushing’s.
Symptoms of Canine Cushing's Disease
The symptoms of Cushing’s Disease can vary from mild to severe and are often gradual, which makes it challenging for pet owners to recognise immediately. However, being aware of the signs can help you seek early veterinary care and provide relief for your dog.
Common Symptoms of Cushing’s Disease
- Increased Thirst and Urination: Dogs with Cushing’s often drink and urinate more than usual, a common first sign noticed by pet owners.
- Increased Appetite: Excessive hunger is another hallmark symptom, as elevated cortisol levels stimulate appetite.
- Pot-Bellied Appearance: Cushing’s can cause muscle weakness and fat redistribution, leading to a characteristic pot-bellied look.
- Hair Loss and Skin Issues: Hair may thin or fall out, and skin may become thin, fragile, or develop dark patches.
- Lethargy and Muscle Weakness: Dogs may seem more tired and have decreased strength, particularly in their back legs.
- Panting: Increased panting can occur even when the dog is not hot or stressed.
- Recurring Infections: High cortisol levels suppress the immune system, leading to frequent infections, especially urinary tract infections.
When to Seek Veterinary Care
If you notice any combination of these symptoms in your dog, especially if they’re middle-aged or older, it’s essential to schedule a vet visit. Early diagnosis can help in managing symptoms and slowing the disease’s progression.
Causes of Cushing’s Disease in Dogs
Understanding the underlying causes of Cushing’s Disease can help in diagnosis and treatment. While the exact causes may vary, certain factors are known to contribute to the development of this condition.
Main Causes of Cushing’s Disease
- Tumours: The majority of Cushing’s cases are due to benign or malignant tumours on either the pituitary gland (pituitary-dependent) or the adrenal glands (adrenal-dependent).
- Long-Term Steroid Use: Prolonged use of corticosteroid medications can lead to iatrogenic Cushing’s. These medications are often prescribed for allergies, arthritis, or autoimmune conditions.
- Age: Cushing’s is more common in middle-aged to older dogs, typically affecting dogs over seven years old.
- Breed Predisposition: Certain breeds, such as Poodles, Dachshunds, Terriers, and Boxers, are more susceptible to Cushing’s, likely due to genetic factors.
Diagnosing Cushing’s Disease
Diagnosing Cushing’s Disease requires specific tests to confirm cortisol overproduction and identify the type of Cushing’s. Veterinarians may use a combination of exams, blood tests, and imaging to confirm the diagnosis.
Diagnostic Steps
- Physical Examination: The vet will assess symptoms such as hair thinning, abdominal distension, and muscle weakness.
- Blood and Urine Tests: Basic bloodwork and urine tests can reveal high liver enzymes and protein levels in the urine, which are indicative of Cushing’s.
- ACTH Stimulation Test: This test measures cortisol levels in the blood before and after an injection of ACTH (a hormone that stimulates the adrenal glands).
- Low-Dose Dexamethasone Suppression Test (LDDS): LDDS is a common test where a low dose of dexamethasone is given, and cortisol levels are measured over time. Dogs with Cushing’s will show little to no suppression in cortisol levels.
- Imaging Tests: Ultrasound or MRI may be used to identify tumours on the adrenal or pituitary glands, helping to differentiate between types of Cushing’s.
Treatment Options for Cushing’s Disease
While there is no cure for Cushing’s Disease, several treatment options can help manage symptoms and improve quality of life. The choice of treatment depends on the type and severity of the disease, as well as the dog’s overall health.
Common Treatments for Cushing’s Disease
Medication
- Trilostane (Vetoryl): Trilostane is a commonly prescribed medication that reduces cortisol production by inhibiting enzymes in the adrenal glands.
- Mitotane (Lysodren): Another option for controlling cortisol production, Mitotane is typically used in dogs with adrenal-dependent Cushing’s.
Pros: Effective at reducing symptoms; can improve quality of life.
Cons: Requires regular blood tests to monitor cortisol levels; potential side effects, such as vomiting or lethargy.
Surgery
Adrenal Tumour Removal
In cases of adrenal-dependent Cushing’s, surgical removal of the affected adrenal gland may be an option if the tumour is operable.
- Pros: Surgery can be curative if successful.
- Cons: Surgery carries risks, particularly in older dogs, and may not be an option for all dogs.
Radiation Therapy
For Pituitary Tumours
Radiation is sometimes recommended for pituitary-dependent Cushing’s, particularly if a tumour is causing neurological symptoms.
- Pros: May help control tumour growth and reduce symptoms.
- Cons: Expensive and requires multiple sessions; may not be accessible to all pet owners.
Management of Iatrogenic Cushing’s
Gradual Reduction of Steroid Medications
For dogs with iatrogenic Cushing’s, slowly reducing or discontinuing steroid medications under veterinary supervision may alleviate symptoms.
- Pros: Often resolves symptoms if the underlying cause is addressed.
- Cons: Requires careful monitoring to avoid withdrawal symptoms or relapse of the initial condition.
Home Care Tips for Cushing’s
Caring for a dog with Cushing’s Disease involves more than just medication. Small lifestyle adjustments can help improve your dog’s comfort and quality of life.
- Provide Fresh Water: Dogs with Cushing’s often drink more, so ensure they have access to clean water at all times.
- Control Diet: A low-fat, high-quality diet with moderate protein can help maintain weight and energy levels. Avoid treats high in fat or sugar.
- Regular Exercise: Light to moderate exercise can help maintain muscle tone and control weight, but avoid strenuous activity.
- Monitor Symptoms: Watch for any changes in behaviour or symptoms, and report them to your vet as adjustments in medication may be needed.
Long-Term Management and Prognosis
With proper management, many dogs with Cushing’s Disease can live comfortably for years. Regular veterinary check-ups and monitoring are essential to manage the disease effectively and adjust treatments as necessary.
Potential Complications
- Diabetes: The high cortisol levels in Cushing’s can lead to insulin resistance, increasing the risk of diabetes.
- High Blood Pressure: Cushing’s may cause hypertension, which requires additional management.
- Urinary Tract Infections: Dogs with Cushing’s are prone to infections due to immune suppression.
- Muscle Loss: Long-term Cushing’s can lead to muscle weakness and loss, affecting mobility.
Regular check-ups and proactive care can help manage these complications and maintain your dog’s quality of life.
FAQs About Canine Cushing’s Disease
1. Is Cushing’s Disease Curable?
Cushing’s Disease cannot be cured in most cases, but it can be managed effectively with medication or surgery, depending on the type and severity of the condition.
2. Can Cushing’s Disease Be Fatal?
If left untreated, Cushing’s can lead to complications like high blood pressure, diabetes, and infections, which can be life-threatening. However, with proper management, dogs can live comfortably for several years.
3. How Expensive is Treatment for Cushing’s?
Treatment costs vary, with medications requiring regular monitoring and vet visits. Surgical and radiation options may be more costly, but financial planning with your vet can help explore feasible options.
Supporting Your Dog Through Cushing’s Disease
From early recognition of symptoms to understanding treatment options, being proactive can make a huge difference for your pet.
Caring for a dog with Cushing’s involves patience, dedication, and ongoing veterinary support. By working closely with your veterinarian, you can help your dog manage symptoms, improve comfort, and continue to live a happy, fulfilling life. Your commitment to your dog’s health is invaluable, and together, you can make each day a little brighter and healthier for them.
Through understanding, empathy, and informed decisions, you’re providing your dog with the best possible care for this condition.
If your pets are in an emergency or if you have general inquiries, please do not hesitate to contact Veterinary Emergency Centre.
General Hotline: 2334-2334
24-Hour Emergency Hotline: 6828-6620
