Common disease in dogs and cats - Cushing's syndrome
What is Cushing's syndrome?
Cushing's syndrome A syndrome caused by excessive secretion of cortisol from the adrenal cortex.Also known as hypercortisolism. Cushing's syndrome is generally divided into: ACTH-dependent hypercortisolism and non-ACTH-dependent hypercortisolism.
ACTH-dependent hypercortisolism is mainly caused by two causes: 1. hypothalamic and ectopically secreted CRH causes excessive secretion of ACTH in the pituitary; 2. pituitary secretion of ACTH hyperfunction, pituitary tumors cause excessive ACTH secretion . This type of Cushing's syndrome is called Cushing's disease.
The main causes of non-ACTH-dependent hypercortisolism: 1. Adrenal cortical tumors or hyperplasia leading to the spontaneous secretion of excess cortisol; 2. Iatrogenic use of excessive cortisol drugs.
Clinical symptoms of Cushing's syndrome
Clinically, the incidence of canine Cushing's syndrome is relatively low. In dogs, the general manifestations of the skin are the skin (neck, ribs, back, waist). There is no pruritic symmetry, the appetite is increased, the amount of urine is increased, and there may be symptoms such as abdominal obesity
Laboratory inspection:
Clinically, AST, ALT, ALP, and TC were elevated in the biochemical examination results of the general diseased dogs. Among them, the first three types were significantly increased, but the treatment value decreased and the condition improved.
Film degree exam:
Common abdominal fat distribution increased, steroid liver disease, liver enlargement, bladder caused by polyuria, tracheal, bronchial calcification. B-ultrasound can help check the adrenal gland, and the adrenal gland is enlarged or normal.
Identification of Cushing's syndrome
Clinically, it is usually identified by the ACTH (adrenocorticotropic hormone) stimulation test and the dexamethasone inhibition test.
The ACTH stimulation test is a relatively simple and reliable method for the diagnosis of adrenal hyperfunction. The accuracy rate is about 80%. If the plasma cortisone concentration after ACTH injection is not higher than before the injection, especially below the normal basal range, It indicates the presence of iatrogenic adrenal hyperfunction or spontaneous adrenal insufficiency.
The low-dose dexamethasone suppression test was used to identify normal dogs and adrenal insufficiency dogs, with an accuracy of approximately 85%. However, low-dose dexamethasone inhibition test results may be affected by anticonvulsant drugs, stress, exogenous glucocorticoids, and non-adrenal diseases. Clinically, dexamethasone sodium phosphate can be used. After a small dose, the plasma cortisone concentration can be measured 8 hours after the patient is used to determine whether the patient is diagnosed with adrenal hyperfunction.
