Flashcards in MEH - Pituitary Disorders Deck (30)
What is the clinical presentation of pituitary tumours?
Mass effect of tumour on local structures leads to visual loss and headache, and there will be an abnormality in pituitary function (hyper- or hyposecretion)
What will happen to a patient if a pituitary tumour grows superiorly?
Visual field loss due to pressure on optic chiasm
What symptoms will occur if a pituitary tumour grows laterally?
Pain and double vision
What is the first hormone to be affected by a tumour of the pituitary?
Which hormones are affected by a medium-sized tumour of the pituitary?
GH, and there is a gonadotropin deficiency so there will be no LH or FSH either. This leads to loss of secondary sexual characteristics in adults and amenorrhoea
What are the symptoms of TSH deficiency?
Low thyroid hormones, cold, weight gain, tiredness, slow pulse
What are the symptoms of ACTH deficiency?
Low cortisol, tired, dizzy, low BP, low sodium - this can be life threatening
What does a TSH and ACTH deficiency indicate about the size of a pituitary tumour?
It is extremely large (late stage)
How is disease on the thyroid, gonadal and prolactin axis tested?
Basal blood test
How is a hormone deficiency tested for?
'Stimulation test' to see if hormone levels will respond
How is a suspected hormone excess tested for?
What visual field characteristic is highly suggestive of a pituitary tumour?
What is a prolactinoma?
Prolactin-secreting pituitary tumour
What is the difference between a micro- and a macroadenoma?
Macroadenoma is over 1cm, micro is under 1cm
How are prolactinomas treated?
The tumour will shrink if the patient takes a dopamine agonist regularly
What are the symptoms of hyperprolactinaemia in women?
Menstrual disturbance, fertility problems, galactorrhoea
Why do men often present later than women with hyperprolactinaemia?
They do not have the symptoms of amenorrhoea to alert them
If the prolactin level is <5000, is it likely to be due to prolactinoma?
It may be due to disinhibition (stalk effect)
What are the long term complications of untreated acromegaly?
- premature cardiovascular death
- increased risk of colonic tumours
- increased risk of thyroid cancer
- disfiguring body changes
- hypertension and diabetes
How can acromegaly be treated?
- remove tumour in trans-sphenoidal hypophysectomy
- reduce GH secretion
- block GH receptor
What is Cushing's disease?
ACTH-secreting pituitary tumour
What is the classical change in appearance seen in Cushing's disease?
- round, pink face with round abdomen
- skinny, weak arms and legs
- thin skin and easy bruising
- red stretch marks on abdomen
- high BP and diabetes
- fat pad on back
What is the difference between Cushing's disease and Cushing's syndrome?
Cushing's disease is due to a pituitary tumour, while Cushing's syndrome can be caused by other pathologies
What are the symptoms of diabetes insipidus?
Large quantities of pale (insipid) urine are passed, extreme thirst due to fluid loss
What causes diabetes insipidus?
Insufficient ADH hormone secretion means that water is not re-absorbed at the kidneys, so there is high urine secretion
What is the difference between cranial and nephrogenic diabetes insipidus?
Cranial DI is due to pituitary disease, while nephrogenic DI is due to kidney disease
What are the consequences of untreated diabetes insipidus?
Severe dehydration, hypernatraemia, reduced consciousness/coma, death
How is cranial DI treated?
Synthetic vasopressin - can use a desmopressin nasal spray, tablets or injection
What is pituitary apoplexy?
A sudden stroke due to bleeding within tumour, or the tumour cutting off blood supply to part of the brain