Pituitary And Adrenal Disease Flashcards
What are causes of hyperprolactinaemia?
Normal pregnancy Pituitary adenomas i.e. Prolactinomas Hypothalamic and pituitary stalk lesions Empty sella syndrome Hypothyroidism CKD Seizures Drugs e.g. Metoclopramide
What is the difference in definition between macro and micro prolactinomas?
Macro >1cm
Micro <1cm
What are the three discriminatory clinical features of hyperprolactinaemia in pregnancy?
Frontal headache
Visual field defects (bitemporal hemianopia due to compression of optic nerve)
Diabetes insipidus
What is the effect of pregnancy on prolactinomas?
They may enlarge, most likely to in the third trimester
What is the treatment for prolactinomas?
Dopamine agonists
Bromocriptine / cabergoline
These are usually discontinued once pregnancy is confirmed
But are safe to be reintroduced if there is concern regarding tumour expansion
What are the clinical and biochemical features of diabetes insipidus?
Excessive thirst and polyuria
Increased plasma osmolality
Decreased urine osmolality (failure to concentrate the urine)
What is the cause of diabetes insipidus?
Relative deficiency of vasopressin (ADH)
What are the four types of diabetes insipidus?
- Central - deficienct production of ADH from posterior pituitary
- Nephrogenic - ADH resistance, associated with CKD
- Transient - increased vasopressinase production by the placenta OR decreased vasopressinase breakdown by the liver (associated with PET / HELLP and AFLP)
- Psychogenic - compulsive water drinking
What is the treatment of Diabetes insipidus?
DDAVP
Good water intake
What are the clinical features of acromegaly / GH excess?
Altered facial appearance Macro glossia Large hands and feet Headaches and sweating HTN, CAD, Cardiomyopathy, IGT / DM Hyperprolactinaemia
Does GH cross the placenta?
No
What is the effect of acromegaly on pregnancy?
Increased risk of GDM and macrosomia
What is the treatment of acromegaly in pregnancy?
Dopamine agonists
Bromocriptine and cabergoline
Not as effective as they are in hyperprolactinaemia, but are still effective in approx 50% cases
What are causes of hypopituitarism?
Pituitary surgery Radiotherapy Pituitary or hypothalamic tumours Postpartum pituitary infarction (Sheehan’s syndrome) Pituitary haemorrhage Lymphocytic hypophisitis
What is the pathophysiology of Sheehan’s syndrome?
Usually presents following PPH with hypotension
Anterior pituitary is particularly vulnerable to hypotension in pregnancy
Infarction
What are the clinical features of Sheehan’s syndrome?
Most commonly presents with hypoprolactinemia, but can present with acute pituitary failure.
Failure of lactation Persistent amenorrhoea, infertility Loss of auxiliary and pubic hair Hypothyroidism Adrenocortical insufficiency
What is the management of acute pituitary insufficiency?
IV fluids
Dextrose
Corticosteroids - IV hydrocortisone
Levothyroxine
What are the clinical features of Cushing’s syndrome?
Excessive weight gain Extensive purple striae DM HTN Easy bruising Headache Hirsutism Acne Proximal myopathy (discriminating feature in pregnancy)
What is the cause of Cushing’s syndrome?
Most common cause is exogenous steroids.
Outside pregnancy: 80% due to pituitary adenomas
In pregnancy: <50% due to pituitary adenomas. Most caused by adrenal adenomas or adrenal carcinoma
What are the clinical features of Conn’s Syndrome?
Conn’s = hyperaldosteronism
HTN and hypokalaemia
What are the causes of Conn’s?
- Adrenal aldosterone-secreting adenoma
- Adrenal carcinoma
- Bilateral adrenal hyperplasia
What are Phaeochromocytomas?
Tumours of the adrenal medulla
Secreting excess catecholamines
What is the effect of pregnancy on phaeochromocytomas?
Potentially fatal hypertensive crises may be precipitated by
- labour, delivery, GA or opiates
What is the effect of phaeochromocytomas on pregnancy?
Increased maternal and fetal mortality rate
Maternal death
- arrhythmia
- cerebrovascular accidents
- pulmonary oedema
What is the treatment of Phaeochromocytoma?
Alpha-blockade to control HTN
Followed by beta-blockade
Surgical removal is the only cure
What are the clinical features of Addison’s disease?
Adrenocortical failure: causing glucocorticoid and mineralocorticoid deficiency
Weight loss Nausea, vomiting Postural hypotension Weakness, lethargy Hyperpigmentation
What is the pathogenesis of Addison’s disease?
Autoimmune destruction of the adrenal glands by adrenal antibodies
TB is another main cause
Primary adrenocortical failure resulting in deficiency of
- glucocorticoids
- mineralocorticoids
- androgens
What is the management of Addison’s disease in pregnancy?
Maintenance hydrocortisone and fludrocortisone
Maintenance steroids
Labour: parenteral hydrocortisone as women are unable to mount an increased output of endogenous steroids that normally accompanies labour and delivery
During delivery, 100 mg hydrocortisone should be injected at the onset of active labour (contractions every 5 min for the last hour, or cervical dilation > 4 cm), followed by either continuous infusion of hydrocortisone 200 mg.24 h−1, or hydrocortisone 50 mg intramuscularly every 6 h, with rapid tapering (over 1–3 days) to the regular replacement dose after an uncomplicated delivery.
What is the most serious risk in congenital adrenal hyperplasia?
Salt losing crisis
What is an important (but rare) side effect of cabergoline?
Valvulopathy
In Addison’s disease i.e. adrenal insufficiency, what are indication to increase the dose of corticosteroids or parenteral hydrocortisone?
Surgery Labour Infection Other significant stress Unwell - double the dose
