The Pituitary Gland Flashcards
What are some hormones released from the anterior pituitary?
TSH - thyroid
ACTH - adrenal
FSH and LH - ovary
FSH and LH - testes
GH - bone and soft tissues
What can cause compression of the optic chiasm?
Suprasellar extension of pituitary gland
What does pituitary compression on optic chiasm cause?
Bitemporal hemianopia
What is the management for hypersecretion of pituitary tumours?
Dopamine agonists - prolactinoma
Somatostatin analogues - acromegaly
GH receptor antagonist - acromegaly
What is management for hyposecretion of normal pituitary?
Cortisol, T4, sex steroids and GH
Desmopressin
What is the management for pituitary tumour?
Surgery - mainly trans sphenoidal
Radiotherapy
What are some hypersecretion diseases?
GH - acromegaly
ACTH - Cushing’s disease
Prolactin - hyperprolactinaemia
What are some hyposecretion diseases?
Anterior - FSH/LH, GH, ACTH and TSH
and posterior - vasopressin
What are some clinical features of acromegaly?
Spade like hands
Wide feet
Coarse facial features
Thick lips and tongue
Carpal tunnel syndrome
Sweating
What are some complications of acromegaly?
Headache, chiasmal compression, DM, hypertension, cardiomyopathy, sleep apnoea, accelerated OA and colonic polyps
How is acromegaly diagnosed?
If IGF-1 is elevated and then conformation with OGTT test
MRI of pituitary
Check vision
Describe Cushing’s disease
Excess corticosteroids
Cortisol is a catabolic hormone so causes tissue breakdown (weak skin, muscles and bones), sodium retention (hypertension) and insulin antagonism (DM)
What are some high value symptoms of Cushing’s disease?
Skin atrophy
Spontaneous purpura
Proximal myopathy
Osteoporosis
Growth arrest in children
What are some intermediate value symptoms of Cushing’s disease?
Pink striae
Facial mooning and hirsutism
Oedema
What can cause ACTH dependant Cushing’s disease?
Pituitary tumour
Ectopic ACTH secretion - ex. lung carcinoid
What can cause ACTH independent Cushing’s disease?
Adrenal tumour
Corticosteroid therapy - asthma and IBD
What are some clinical manifestations of hyperprolactinemia in women?
Galactorrhoea - milk production
Menstrual irregularity
Infertility
What are some clinical manifestations of hyperprolactinaemia in men?
Galactorrhoea
Impotence
Visual field abnormalities
Headache
Extraocular muscle weakness
Anterior pituitary malfunction
What are the causes of hyperprolactinaemia?
Pregnancy, lactation and stress
DA depleting and DA antagonist drugs
Primary hypothyroidism and pituitary lesions
What drugs may cause hyperprolactinaemia?
DA antagonists
DA depleting drugs
Oestrogens
Some antidepressants
What are the clinical features of hypothyroidism in adults?
Tiredness, weight gain, depression, reduced libido, impotence, menstrual problems, skin pallor and reduced body hair
What are some clinical features of hypothyroidism in children?
Reduced linear growth and delayed puberty
What test is used for diabetes insipidus?
Water deprivation test
DDAVP added and concentrates in diabetes insipidus
Give fluid deprivation period before
What is some differential diagnoses for diabetes insipidus?
Idiopathic, post-trauma, metastatic carcinoma, craniopharyngioma, other brain tumours and rare (sarcoidosis)
What are the beneficial effects of somatostatin analogues in acromegaly?
Improve soft tissue overgrowth, sweating, headaches and sleep apnoea
Normalises GH and iGF-1 levels
Induces tumour shrinkage
Reduces morbidity + mortality
What are the somatostatin slow release injections?
Monthly injections of octreotide LAR and Lanreotide autogel
What are some adverse effects of somatostatin analogues?
Nausea, cramps, diarrhoea, flatulence
Cholesterol gallstones
Slow release preparations require monthly IM/SC injections
High cost
Describe pituitary radiotherapy
Use is declining
Acts slowly
Can cause hypothyroidism
Describe microprolactinoma
<10mm
Usually women with galactorrhoea, amenorrhoea, infertility and serum PRL <5000mU/I
Most shrink
What is the treatment of microprolactinoma
Dopamine agonists
Cabergoline normoprolactinaemia, ovulatory cycles and fertility usually restored
Describe macroprolactinoma
> 10mm
Typical response to DA agonists - rapid fall in serum PRL, tumour shrinks, visual improvement and recovery of pituitary function
What are some adverse effects of dopamine agonists?
Nausea and dizziness
Impulse control disorders - addictive behaviours
Fibrotic disorders - lung and cardio
