Feline Hyperadrenocorticism (Cushing's Disease)
Also known as: Cushing's Disease, Hyperadrenocorticism
⚠ Emergency Warning Signs
Significant skin tearing or a wound that won't heal warrants prompt veterinary attention given how fragile affected cats' skin can become.
Overview
Feline hyperadrenocorticism (Cushing's disease) is a rare condition in cats — notably much less common than in dogs — caused by excess cortisol production, usually from a pituitary gland tumor. It's particularly notable for a strong, distinctive association with diabetes mellitus in cats and for causing unusually fragile skin, which is a distinguishing clinical clue.
Symptoms
- Fragile, easily-torn skin
- Poorly-controlled diabetes
- Pot-bellied appearance
- Muscle wasting
Causes
Most commonly a benign pituitary gland tumor causing excess ACTH (and downstream cortisol) production; less commonly, a tumor of the adrenal gland itself. Feline Cushing's disease most commonly results from a pituitary tumor causing overproduction of the hormone that stimulates the adrenal glands, leading to excess cortisol production — genuinely rarer in cats than in dogs, and notably, a substantial proportion of feline Cushing's cases occur in cats who also have diabetes mellitus, with the excess cortisol actively working against normal insulin function.
Risk Factors
Middle-aged to older cats; a strong association exists with concurrent diabetes mellitus, and many affected cats are diagnosed with Cushing's during investigation of poorly-controlled diabetes.
Transmission
Not applicable — not an infectious disease.
Incubation Period
Not applicable; develops gradually over time as excess cortisol accumulates its effects.
Disease Stages & Progression
Gradual development of the classic Cushing's signs alongside often difficult-to-control concurrent diabetes; notably, unlike in dogs, skin fragility is a prominent and distinctive feature in cats, sometimes progressing to skin tearing with minimal trauma.
Early Warning Signs
Increased thirst and urination (often initially attributed to the frequently concurrent diabetes), poor coat condition. Thin, fragile skin that tears easily (sometimes alarmingly, even from routine handling) is a genuinely distinctive feature of feline Cushing's specifically; alongside this, increased thirst/urination, a pot-bellied appearance, and poor coat quality are common, often overlapping significantly with symptoms of the diabetes that frequently co-occurs.
Advanced Symptoms
Pot-bellied appearance, thin/fragile skin that may tear easily (a notably distinctive feature in cats), poor wound healing, muscle wasting, and diabetes that's unusually difficult to control despite appropriate insulin therapy — this last point is often what prompts vets to specifically investigate for Cushing's in a diabetic cat.
Diagnostic Methods
A combination of clinical suspicion (particularly poorly-controlled diabetes plus other Cushing's signs), specific endocrine testing, and imaging; given the disease's rarity in cats, diagnosis can take real time and often benefits from a specialist's involvement. Diagnosis is genuinely more complex in cats than in dogs, often requiring a combination of specific hormone stimulation/suppression tests and imaging (ultrasound or CT of the adrenal glands) — a veterinary internal medicine specialist's involvement is often valuable given how comparatively uncommon and diagnostically nuanced this condition is in cats.
Veterinary Examination Process
Assessment of skin fragility/thinness, body shape, muscle condition, and coat quality, alongside diabetes control history.
Recommended Lab Tests
ACTH stimulation test or low-dose dexamethasone suppression test, blood glucose monitoring given the diabetes association.
Diagnostic Imaging
Abdominal ultrasound to assess adrenal gland size/appearance; advanced imaging (CT/MRI) to look for a pituitary tumor if surgery or targeted radiation is being considered.
Blood Test Indicators
Specific endocrine testing (e.g., ACTH stimulation test, low-dose dexamethasone suppression test) is needed for diagnosis — these are more specialized tests than routine bloodwork and require a vet experienced in feline endocrinology to interpret given how uncommon this disease is in cats.
Biopsy / Histopathology
Not typically used for diagnosis; adrenal or pituitary tissue evaluation would only occur in the context of surgery.
Differential Diagnoses
Other causes of poor coat/skin condition and difficult-to-control diabetes — specific endocrine testing is needed to confirm Cushing's given how rare and easy to overlook it is in cats.
Home Monitoring Guidance
Careful handling given skin fragility, monitoring diabetes control closely, and watching for any new skin tears or slow-healing wounds.
Veterinary Treatment Options
Treatment options include medication to reduce cortisol production, surgical removal of the adrenal gland (if adrenal-based) or pituitary surgery/radiation (if pituitary-based, done at specialized centers) — this is a genuinely complex disease to manage and typically benefits from referral to a veterinary internal medicine specialist given how uncommon it is in general practice experience.
Surgery Requirements
Adrenalectomy (if adrenal-based) or pituitary surgery (if pituitary-based, at a specialized center) are potential options depending on the specific case and tumor location.
Recovery Timeline
Variable and often prolonged, given the disease's complexity — improvement in diabetes control is sometimes one of the more noticeable positive signs of successful treatment.
Possible Complications
Skin tearing and poor wound healing, difficult-to-control diabetes, and the general complexity/risk of the underlying tumor and its treatment.
Long-Term Management
Ongoing monitoring of cortisol levels and diabetes control, careful handling given skin fragility.
Prevention
No known specific prevention.
Vaccination Availability
Not applicable — not an infectious disease.
Prognosis
Guarded to fair, reflecting the disease's complexity and the specialized treatment it typically requires; some cats show meaningful improvement, particularly in diabetes control, with appropriate treatment.
References
American College of Veterinary Internal Medicine (ACVIM).
Medications Used
- Medications to reduce cortisol production (e.g., trilostane), used with careful monitoring
- Concurrent diabetes management, which often becomes easier to control once Cushing's itself is addressed
Estimated Treatment Cost by Country
| Country | Estimated Cost Range | Notes |
|---|---|---|
| IN | 15,000–150,000 INR | |
| US | 1,500–8,000 USD | |
| UK | 1,200–6,000 GBP | |
| AU | 2,000–10,000 AUD | |
| JP | 100,000–700,000 JPY | |
| DE | 1,200–6,000 EUR | |
| BR | 3,000–15,000 BRL |
Frequently Asked Questions
Why is my diabetic cat suddenly getting worse despite treatment?
Poorly-controlled diabetes despite appropriate insulin therapy is one of the more common clues that leads vets to investigate for Cushing's disease in cats specifically — it's worth raising with your vet if this pattern describes your cat's situation.
Is this the same as in dogs?
The underlying hormonal mechanism is similar, but it's genuinely much rarer in cats, and the skin fragility feature is notably more prominent and distinctive in cats than the more typical presentation in dogs.
Why is my cat's skin tearing so easily?
Skin fragility is a distinctive feature of feline Cushing's disease specifically — it's a real, physical consequence of the excess cortisol's effect on skin structure, not something to attribute to rough handling.
Is this treatable?
Yes, though it's a complex disease — treatment options exist (medication, surgery) and are usually best managed with input from a veterinary internal medicine specialist given how uncommon this diagnosis is in general feline practice.