Cushing’s syndrome, hypercortisolism and hyperadrenocorticism can look like interchangeable words when you first read a veterinary report. The 2025 Agreeing Language in Veterinary Endocrinology (ALIVE) consensus gives them more specific meanings. Understanding those distinctions can help you ask what a term means in your dog’s particular record.
Why the Words Are Changing
The 2025 ALIVE consensus on adrenal terminology brought together 10 experts from the European Society of Veterinary Endocrinology and the Society of Comparative Endocrinology. Through four rounds of a modified Delphi method, they agreed on definitions for 35 adrenal disease concepts. A further endorsement survey involved 78 members of the two societies, with every definition receiving majority support.
The purpose was a common language for clinical practice, research and teaching. For an owner, the useful question is what each word identifies: the clinical syndrome, the hormone activity involved, or the classification of the condition. Those are related descriptions, but they answer different questions.
Cushing's Syndrome and Hypercortisolism
ALIVE uses Cushing’s syndrome as the umbrella term for clinical syndromes caused by a chronic excess of glucocorticoid activity. That activity may come from hormones produced within the body or steroid hormones given from outside it. The definition therefore covers more than one underlying cause.
Hypercortisolism has a narrower meaning: excessive glucocorticoid activity due to cortisol. ALIVE recognises that demonstrable hypercortisolism does not always accompany, or lead to, Cushing’s syndrome. A finding about cortisol activity and a description of a clinical syndrome are not automatically the same statement.
The consensus discourages using “Cushing’s disease” or “hyperadrenocorticism” as the umbrella name. If either appears in a report, ask which meaning is intended rather than assuming that the wording alone identifies the form.
How the Different Forms Are Classified
For naturally occurring Cushing’s syndrome, ALIVE divides the classification into ACTH-dependent and ACTH-independent forms. ACTH stands for adrenocorticotropic hormone. Keeping those category names separate from the more specific names beneath them makes the classification easier to read.
- ACTH-dependent: the classification lists pituitary-dependent hypercortisolism and ectopic ACTH, as well as subdiagnostic Cushing’s syndrome.
- ACTH-independent: it lists adrenal-dependent hypercortisolism and aberrant adrenal receptor expression, as well as subdiagnostic Cushing’s syndrome.
- Iatrogenic Cushing’s syndrome: this is listed separately from naturally occurring disease and concerns glucocorticoid excess from administered steroid hormones.
These names provide a framework for describing the form involved. When discussing a record, it is reasonable to ask whether a broad category has been established or whether a more specific form has been identified. The classification itself is a vocabulary, rather than a set of numbered stages.
When Tests Come Back Normal: “Subdiagnostic” Cushing's
ALIVE defines subdiagnostic Cushing’s syndrome as a situation in which a dog appears to have the syndrome but dynamic tests of pituitary-adrenal function fall within normal reference intervals. The definition requires normal results from both dexamethasone suppression testing and ACTH stimulation testing. It identifies “atypical” and “occult” Cushing’s as previous names for this concept.
The consensus also distinguishes these dynamic tests from the urinary corticoid:creatinine ratio and an endogenous ACTH measurement. Neither of those is a dynamic test. If this terminology appears in your dog’s notes, ask your veterinarian which tests the description refers to and how the results fit the observed signs.
Addison's and Primary Hypoadrenocorticism
ALIVE defines hypoadrenocorticism as reduced adrenal cortex function resulting in deficiency of glucocorticoids, mineralocorticoids, or both. It can be naturally occurring or iatrogenic. This umbrella term covers more than primary hypoadrenocorticism alone.
Addison’s disease is a synonym specifically for primary hypoadrenocorticism. ALIVE encourages the more descriptive name “primary hypoadrenocorticism” to reduce confusion. That condition involves injury to the adrenal cortex and can arise naturally or through medical interventions. The distinction is about the condition being named; it is not an instruction about medication.
Reading Your Dog's Records
As you read, separate the words describing signs from those describing hormone activity and the proposed classification. You might ask: “Does this term describe the syndrome or a test finding?” and “Which form has been identified?” These questions keep the conversation focused on what the record actually says.
For more context, the diagnosis guide introduces the tests owners may encounter, while the clinical-score guide explains a shared way to describe signs. Your veterinarian can interpret the terminology alongside your dog’s examination and results.