Pituitary Disease Flashcards
What level of prolactin raises suspicion of a prolactin-secreting tumour being present?
> 5000
How are prolactinomas treated medically?
Cabergoline (a dopamine agonist)
What are known side-effects of dopamine agonists?
Nausea
Vomiting
Depression
What causes acromegaly?
Excess growth hormone secretion
Why would onset of excess GH in childhood cause gigantism, but not when starting in adults?
As in children epiphyseal fusion has not yet occurred.
What pathology occurs in acromegaly?
Thickening of the soft tissue - most will die due to heart failure.
What is the most common cause of acromegaly?
Pituitary adenoma
How is acromegaly treated?
Surgical removal of the adenoma.
If not suitable, give loreotide (a synthetic somatostatin). This will cause tumour shrinkage. Dopamine agonists can also be effective.
What should acromegaly patients be screened for?
Bowel cancers (as increased risk of polyps)
Signs of CVD
Sleep apnoea (if present give CPAP)
What is the issue in Cushing’s syndrome?
Excess cortisol production
Results in protein loss, myopathy, osteoporosis, and thinning of the skin.
What mental health act impacts can Cushing’s syndrome have?
Psychosis
Depression
What are the key features of Cushing’s syndrome?
Thin skin
Proximal myopathy
Osteoporosis
How is Cushing’s syndrome tested for?
High-dose dexamethasone suppression test
What is the difference between Cushing’s disease and Cushing’s syndrome?
Cushing’s disease involves the pituitary only, whereas Cushing’s syndrome is pathology elsewhere in the body.
Critically, both produce the same symptoms.
What is the most common cause of Cushing’s?
Pituitary disease
What are common causes of Cushing’s syndrome?
Adrenal tumour
Ectopic ACTH from thymus/lungs/pancreas
What are symptoms of hypopituitarism?
Amenorrhoea
Infertility
Impotence
Loss of facial hair
Gynaecomastia
Obesity
What are potential causes of hypopituitarism?
Surgery
Granulomatous disease (e.g. sarcoidosis)
Autoimmune (e.g. Sheehan’s syndrome)
How is hypopituitarism managed?
Thyroxine
Hydrocortisone
ADH
GH
HRT/Testosterone (gender-dependent)
What is a potential complication of testosterone therapy?
Polycythaemia (which increases risk of stroke/MI)
What pathology should be screened for in those about to initiate testosterone therapy?
Prostate cancer - as therapy can cause enlargement of the gland.
What test is used to investigate diabetes insipidus?
Water deprivation test
How is cranial DI differentiated from nephrogenic DI?
In cranial DI, desmopressin (synthetic ADH) injection will cause an increase in osmolarity to normal levels.
However, in nephrogenic DI there will not be a response to desmopressin.
