Pituitary Gland Flashcards
What hormones are secreted from the anterior and posterior pituitary gland?
6 Anterior:
- LH
- FSH
- TSH
- Prolactin
- ATCH
- GH
2 Posterior:
- ADH
- Oxytocin
What is a pituitary adenoma?
A benign tumour of the pituitary gland resulting in:
- excess hormone production of a particular hormon
- Mass effect
- Reduced production of all other hormones in the pituitary
What condition is caused by excess GH
Acromegaly
what condition is caused by excess ACTH / Cortisol
Cushings
What condition is caused by excess prolactin
Prolactinoma
What are the features of functioning and non functioning adenomas
Functions = hormone producing and therefore are identified earlier due to the effects of excess hormones
Non functioning = non hormone producing and therefore identified later due to mass effects
What symptoms are caused due to mass effect?
- Bitemporal hemianopia
- CN III, IV and VI palsy
- headaches
- Change in appetite, temperature regulation, thirst, GCS etc if the hypothalamus is involved
Features of a prolactinoma
- Gynocomastia
- decreased libido
- Oligomenhorrea
- menhorragia
- Amenhorrea
- Small testes
- Impotence in males
- loss of facial hair
- osteoporosis
- Decreased fertility
Investigations in prolactinoma
- Basal prolactin (Non stressful 9am-4pm)
- TFTs
- pregnancy test
- MRI of pituitary
Treatment of prolactinoma
Dopamine agonist + referral
Signs of acromegaly
- Growth of bone and soft tissues
- Widely spaced teeth
- Prognathism - protruding jaw
- Boggy palms
- Big tounge, big heart, bit thyroid
- increased sweating
- high BP, arrhythmias
- Prominent forehead
- Increased skin creases
- Carpel tunnel and thenar eminence waisting
Symptoms of acromegaly
- headache
- decreased libido
- amenhorrea
- galactorrhea
Why do you get loss of libido and amenhorrea in acromegaly
because 1/3 of patients also have increased prolactin
complications of acromegaly (ABCDE)
A - Arrhythmias B - BP high C - Carpel Tunnel and Colorectal cancer D - Diabetes E - Enlarged hands, tongue, feet and goitre F - Fields and bi temporal hemianopia
Why is there a risk of getting Diabetes in Acromegaly?
Acromegaly is due to the increased secretion of GH and IGH (insulin like growth hormone) which acts as an “anti insulin” and causes diabetes
What screening is required in people with acromegaly
Colonoscopy annually after the age of 40 due to the increased risk of colorectal cancer
Investigations of acromegaly
Bloods:
- OGTT
- Glucose
- GH / IGF
- Calcium
- Phosphate
Bedside:
- ECG (arrhythmias)
- Urine dip (Glucose)
Other
- Visual fields
Treatment of acromegaly
- Somatosatin anologues
- surgical removal
Definition of cushings
Excess ATCH and therefore Excess cortisol due to either ATCH dependent (pituitary problem / ectopic tissue) or Non ATCH dependent (adrenal adenoma)
Features of cushings disease
LEMON ON A STICK!
- Increase central obestity
- Moon face
- Acne
- Intrascapular fat pads
- Frontal balding
- Thin limbs
- hyper pigmentation
- osteoporosis
- Diabetes
Investigations of cushings disease
- Low dose dexamethosone test (high dose is secdond line)
- 24hr urinary cortisol
- Plasma ATCH if any of the above are positive
treatment of cushings disease
if drugs are the cause (steroids) = Stop the drugs
otherwise = surgery to remove pituitary adenoma
definition of hypothalamic pituitary disease
decrease in all pituitary hormones
What are the features of hypothalamic pituitary disease
- Fatigue
- Myalgia
- hypotension (Low GH)
- Diabetes insidious with polyuria and polydipsia (low ADH)
- Hypothyroidism (low TSH)
