Endocrine_CCT (2) Flashcards
What features would decrease in growth hormone cause?
- central obesity
- atherosclerosis
- dry, wrinkly skin
- low strength and low balance and wellbeing
- decrease in excersie ability
- decreased cardiac output
- osteoporosis
- decreased glucose
What feature would gonadotropism (due to low pituitary secretion) cause?
Decreased gonadotrophins, FSH__,LH__:
- oligomenorrhoea or amenorrhoea
- decreased fertility
- decreased libido
- osteoporosis
- breast atrophy
- dyspareunia
- erectile dysfunction
- decreased muscle bulk
- hypogonadism
What would decrease in the following cause:
- prolactin
- TSH
- ACTH
- Prolactin -absent lactation
- TSH -hypothyroidism
- ACTH -adrenal insufficiency.
What is panhypopituitarism
- Panhypopituitarism is a deficiency of all anterior pituitary hormones
- caused by radiation/surgery or a pituitary tumour
Investigations in hypopituitarism disorders
- LH and FSH -either decreased or normal
- Testosterone or oestradiol are low
- TSH is low or normal
- T4 is low
- Prolactin might be high due to the loss of hypothalmic dopamine that normally inhibits its release
- Insulin-like growth factor-1 is decreased
- Cortisol is low
- U&E -will show low sodium and that is to the dilution.
- Hb is low, normochromic, normocytic
What may happen to prolactin in hypopituitarism?
Prolactin might be high due to the loss of hypothalmic dopamine that normally inhibits its release
Other tests in hypopituitarism
- Short Synacthen Test -and this is to assess the adrenal axis
- Insulin tolerance test
It involves IV insulin to induce hypoglycaemia causing stress to increase the cortisol and GH section. It is done in the morning and water only taken at 10pm.
- Arginine and growth hormone releasing hormone test
- Glucagon stimulation test is alternative when ITT is contraindicated
Management of hypopituitarism
- hormone replacement and treatment of underlying cause
- Hydrocortisone -for 2ndary adrenal failure
- Thyroxine if hypothyroid
- Testosterone enanthate 250mg IM every 3 weeks, daily topical gels or buccal mucoadhesive tablets
- Oestrogen, transdermal oestradiol patches or contraceptive pill, as this will eceed replacement needs
- to prevent osteoporosis (if hypogonadism)
- Gonadotropin therapy is needed to induce fertility in both men and woman.
Symptoms of acromegaly
- Acroparaesthesia (paraesthesia in the extremities)
- Amenorrhoea
- Decreased libido
- Increase sweating
- Snoring
- Arthralgia
- Backache
- ‘my rings won’t fit nor my old shoes’
- Curly hair
- Malocclusion (incorrect relation between two teeth)
Signs of acromegaly
- increase growth of hands, jaw and feet
- Coarsening face
- Wide nose
- Big supraorbital ridges
- Macroglossia
- Widey spaced teeth
- Puffy lips, eyelids and skin is oily.
- Scalp folds
- Skin darkening
- Acanthosis Nigerians
- Laryngeal dyspnoea
- Obstructive sleep apnoea
- Goitre
- Carpel tunnel signs
- Hemianopia
Complications of acromegaly
- Impaired glucose tolerance
- Vascular: increase blood pressure, LV hypertrophy
- Cardiomyopathy
- Arrhythmias
There is an increased risk of ischaemic heart disease and stroke →this is due to BP and insulin resistance and GH-induced increase in fibrogen and decrease in protein S.
- Neoplasia, there is an increased risk of colon cancer
Ix in acromegaly
- ↑glucose
- ↑Calcium and phosphate
- An oral glucose tolerance test is needed
- MRI look for hypopituitarism, visual fields and acuity and ECG, Echo and old photos if possible.
Is GH test reliable in testing for acromegaly?
GH: don’t rely on a random GH as the secretion is pulsatile and during peaks acromegalic and normal levels overlap.
GH also increases in stress, sleep, puberty and pregnancy.
What’s the definitive test for acromegaly?
Definitive test is the oral glucose tolerance (OGTT) with serial GH measurements
Oral glucose tolerance test
- in normal patients GH is suppressed to < 2 mu/L with hyperglycaemia
- in acromegaly there is no suppression of GH
- may also demonstrate impaired glucose tolerance which is associated with acromegaly
Management of acromegaly
Aim: to correct or prevent the tumour compression by excising the lesion and to reduce the GH and IGF-1 levels
Three-part strategy of treatment:
- Transsphenoidal surgery is the first line
- If surgery fails to correct the hypersections then try Somatostatin analogues or radiotherapy
- The GH antagonist pegvisomant
Classification of hypothyroidism (3)
Hypothyroidism may be classified as follows:
- primary hypothyroidism: there is a problem with the thyroid gland itself, for example an autoimmune disorder affecting thyroid tissue
- secondary hypothyroidism: usually due to a disorder with the pituitary gland (e.g.pituitary apoplexy) or a lesion compressing the pituitary gland
- congenital hypothyroidism: due to a problem with thyroid dysgenesis or thyroid dyshormonogenesis
Common cause of hyperthyroidism
- thyrotoxicosis