Session 8-Pituitary Disorders Flashcards
What are the clinical presentations of pituitary tumours?
Visual loss
Headache
What can a gonadotropin deficiency lead to?
Delayed puberty in children
Loss of secondary sexual characteristics in adults
Loss of periods
What can a TSH deficiency lead to?
Cold
Weight gain
Tiredness
Slow pulse
What can an ACTH deficiency lead to?
Tired
Dizzy
Low BP
Low sodium
What is a prolactinoma?
Prolactin-secreting pituitary tumour
What size of tumour is classed as a:
1) macro-adenoma
2) micro-adenoma?
1) >1 cm
2) <1 cm
True or false: prolactinomas are treated with an operation
FALSE - tablets
What inhibits prolactin and can therefore be used to shrink a prolactinoma?
Dopamine agonist as dopamine inhibits prolactin
True or false: prolactin inhibits LH
TRUE - also inhibits FSH
What are the symptoms of hyperprolactinaemia in women?
Menstrual disturbance
Fertility problems
Galactorrhoea (milky discharge)
What are the symptoms of hyperprolactinaemia in men?
Men present later than women as don’t have periods
Usually larger tumours
Mass symptoms such as visual loss
True or false: if prolactin > 5000, high prolactin might be due to disinhibition (stalk effect) rather than active prolactin secretion
FALSE - ^ is if prolactin < 5000
If >5000, high prolactin due to active prolactin secretion (prolactinoma)
What are the long-term complications of untreated acromegaly?
- premature cardiovascular death
- increased risk of colonic tumours
- probably increased risk of thyroid cancer
- disfiguring irreversible body changes
- hypertension and diabetes
What is the treatment of acromegaly?
- surgical removal of tumour
- reduce GH secretion using dopamine agonist and somatostatin analogues (SSA)
- block GH receptor
What is Cushing’s disease?
ACTH-secreting pituitary tumour
What is the classical change in appearance in someone with Cushing’s disease?
- round pink face with round abdomen
- skinny and weak arms and legs
- thin skin and easy bruising
- red stretch marks (striae) on abdomen
- high BP and diabetes
- osteoporosis
What is the difference between Cushing’s disease and Cushing’s syndrome?
- disease due to pituitary tumour
- syndrome caused by other pathologies
What is diabetes insipidus?
Large quantities of pale urine
Extreme thirst due to fluid loss
What is cranial diabetes insipidus?
Vasopressin deficiency pituitary disease
What is nephrogenic diabetes insipidus?
Vasopressin resistance kidney disease
Which types of pathology cause cranial diabetes insipidus?
Inflammation
Infiltration
Malignancy
Infection
What are the consequences of untreated diabetes insipidus?
- severe dehydration
- hypernatraemia
- reduced consciousness, coma and death
What does apoplexy mean?
Stroke
What is the clinical presentation of pituitary apoplexy?
- sudden onset headache
- double vision
- visual field loss
- cranial nerve palsy
- hypopituitarism
When is a stimulation test used in a dynamic assessment of HPA and GH axes?
Suspected hormone deficiency
When is a suppression test used in a dynamic assessment of HPA and GH axes?
Suspected hormone excess
What is used to test whether there is an excess of ACTH in the adrenal axis?
Suppress ACTH axis with steroids (dexamethasone)
What is used to test whether there is a deficiency of ACTH in the adrenal axis?
- Direct stimulation of adrenals by ACTH
- Response to hypoglycaemic stress (insulin stress test)
What is used to test whether there is a deficiency of GH in the GH axis?
Response to hypoglycaemic stress (insulin stress test)
What is used to test whether there is an excess of GH in the GH axis?
Suppress GH axis with glucose load (glucose tolerance test)
