Clinical Aspects of Pituitary Disease Flashcards
What disease come from hypersecretion of the pit.gland? Causes?
Acromegaly - GH
Cushing’s - ACTH
Hyperprolactinaemia - Prolactin
Tumours
Hormones affected by hyposecretion? Cause?
AG - FSH/LH, GH, ACTH and TSH
PG - vasopressin
Mostly due to tumours too
What is FSH and LH?
Follicle stimulating hormone
Luteinizing hormone
What is another common presentation of a pit. tumour?
Bitemporal hemianopsia due to optic chiasmal compression
Clinical features of acromegaly?
Soft tissue like overgrowth =
Spade like hands Wide feet Thick lips and tounge Space between teeth Sweating Carpal tunnel syndrome
Complications form acromegaly?
Diabetes Hypertension Cardiomyopathy Sleep apnoea Headaches Chaismal compression = bitemporal hemianopsia
Diagnosis of acromegaly?
Test to see if GH can be supressed via a OGTT
Is IGF-1 elevated?
Glucose will also be elevated
Is the rest of pit. gland function normal?
Is vision normal?
tumour on MRI?
What is cushings?
Excess cortisol
What does cortisol do?
A catabolic hormone
Tissue breakdown causing weakening of skin, muscle and bone
Na retention - causing hypertension and heart failure
Insulin antagonism - causing DM
Symptoms that give high suspicion of cushings?
Moon face with central adiposity but skinny arms and legs, also pink striae Oedema Skin atrophy Spontaneous purpura Proximal myopathy Osteoporosis Growth arrest in kids
Other causes of cushing’s besides a pit. tumour?
ACTH dependant = Ectopic ACTH secretion like a lung carcinoid
ACTH independent = Adrenal tumour - adenoma/carcinoma
Corticosteropid therapy
Cushings disease vs syndrome?
Cushing’s disease is a medical cause of Cushing’s syndrome. Cushing’s disease occurs when a tumor on the pituitary gland causes the gland to produce too much ACTH
What are the clinical manifestations of hyperprolactinaemia in women?
Galactorrhoea in 30-80%
Menstual irregularity
Infertility
What are the clinical manifestations of hyperprolactinaemia in men?
Galactorrhoea - 5% Impotence Visual field abnormalities Heachache Extraocular muscle weakness Anterior pituitary malfunction
What is purpura ?
a condition of red or purple discolored spots on the skin that do not blanch on applying pressure
What is galactorrhoea?
Production of milk when you shouldn’t be making milk
Causes of hyperprolactinaemia?
Physiological - pregnancy, stress, lactation
Pharmacological - Dopamine depleting and dopamine antagonistic drugs
Pathological - 1y hypothyroidism, pit. lesions like prolactinoma or pit. stalk pressure
Drugs that may cause hyperprolactinaemia?
Dopamine antagonists - neuroleptics, anti-emetics Dopamine depleting drugs Oestrogens Some antidepressants Homeopathic or herbal remedies
Clinical features of hypo-pituitarism in adults?
Tiredness Weight gain Depression Reduced libido and impotence Menstrual problems Skin pallor Reduced body hair
Clinical features of hypopituitarism in kids?
Reduced linear growth
Delayed puberty
What is cranial diabetes insipidus?
The hypothalamus/pit gland does not produce enough anti-diuretic hormone/vasopressin
Symptoms of DI?
Polyuria/nocturia
Extreme thirst
DI differentials/causes?
Idiopthic Post-trauma Carcinoma mets Cranio-pharyngioma Other brain tumours Rarer causes like Sarcoidosis
Management of prolactinoma?
Dopamine agonists for
Management for acromegaly?
Somatostatin analogues
GH receptor antagonist
Management for hyposecretion of normal pit. gland?
Cortisol T4 Sex steroids GH Desmopressin
Management for pituitary tumours?
Trans-sphenoidal surgery most common
Radiotherapy
What are the beneficial effects of somatostatin analogues in acromegaly?
Improves soft tissue overgrowth, sweating, headache and sleep apnoea symptoms
Normalise GH and IGF-1 in over 50% of patients
Induce tumour to shrink in the majority
Reduces morbidity and mortality
Name somatostatin analogues?
Octreotide LAR
Lanreotide autogel
Adverse side effects of somatostatin analogues?
Nausea
Cramps
Diarrhoea
Flatulence
Cholesterol gallstones - often asymptomatic
Disadvantages of SS analogues?
Expensive
Slow release preparations need monlthy IM or s/c injections
Is pituitary radiotherapy used often?
No, use is declining as it acts slowly and causes hypopituitarism
When is pituitary surgery carried out?
Mainly for non-functioning pit. tumours and cushing’s
What hormones control the release of prolactin?
Thyrotrophin releasing hormone increases release of prolactin
Dopamine (prolactin inhibiting factor) inhibits the release of prolactin and cancels the effects of thyrotrophin releasing hormone
Dopamine is constantly released in anyone that is not pregnant to stop the effects
Neg. feedback loops that stop high levels of prolactin?
Dopamine released to inhibit it
Gonadotrophin releasing hormone levels are reduced
What is a prolactinoma and what makes it micro/macro?
A functional tumour that divides uncontrollably and makes prolactin
Can compress optic chiasm
Over 10mm is macro and under is micro
Features of micro-prolactinoma
Usually women with galactorrhoea
Amenorrhoea
Infertility
Serum prolactin less than 5000 mU/I
What is amenorrhoea?
Absence of a menstrual period
Treatment of microprolactinoma?
Cabergoline (dopamine receptor agonist)
Ovulatory cycles, fertility and normoprolactinaemia is restored in 70-90%
Dopamine agonist effects on macroprolactinoma?
Rapid fall in serum PRL (hours)
Tumour shrinkage (days/weeks)
Visual improvement (often within days)
Often recovery of pituitary function
80-90% tumours show these responses & most will shrink by at least one half
