Endocrinology Flashcards
(15 cards)
Cushing’s Disease:
- Causes of Cushing’s syndrome
- Symptoms (6)
- Signs (4)
- Investigations
- Management
- DD
Cushing’s Disease:
- Causes of Cushing’s syndrome: exogenous, adrenal cushings (adrenal adenoma - cortisol released), cushings disease (pit tumour - acth released), sclc secreting acth
- Symptoms (6): round face, fat pad on back, central abdominal obesity, purple striae
- Signs (4): proximal myopathy, osteoporosis, hyperglycemia, bruising, htn (high cortisol can exhibit aldosterone activity)
- Investigations: fbc/u+es/hba1c/alc, 24 hour urine cortisol, first line dexamethasone suppression test (give at night and in morning cortisol should be reduced. If not then high dose dexa and if adrenal cushings secreting cortisol should be some - fb reducing cortisol but not if cushings disease), OGTT imapired, hypokalaemic metabolic alkalosis
- Management: if adrenal cushings adrenectomy, if cushings disease transphenoidal removal
- DD: alcoholic/depression also causes false + in dexa test
Acromegaly:
- Definition
- Complications
- Symptoms (11)
- Investigations
- Management
Acromegaly:
- Definition: functional pituitary tumour secreting GHRH
- Complications: cvs disease (hypertrophic heart), bowel cancer, thyroid cancer, htn, diabetes
- Symptoms (11): headache/bitemporal hemianopea, inc size hands/feet, forehead bossing, chin protrusion, wide spaced teeth, carpal tunnel, tongue enlargement, sleep apnoea, excessive sweating (sweat gland hypertrophy), galactorrhoea
- Investigations: serum IGF1 (not GH bc varies throughout the day), if raised then confirm by OGTT (normally glucose suppresses GH but will be impaired here), mri brain, prolactin may be raised
- Management: transphenoidal surgery, if not somatostatin analogues e.g. octreotide which inhibits GH release, or GH rec antagonists pegvisomant (but doesn’t reduce tumour volume so surgery still needed), or dopamine agonists bromocriptine, or ext beam radiotherapy
Hypopituitism:
- Symptoms (4)
- Causes (4)
- Investigations
- Management
- pituitary apoplexy
Hypopituitism:
- Symptoms (4): sexual dysfunction, fatigue, increase weight, postural hypotension, hyponat, if NFPA headache/bitemp hemianopea
- Causes (4): NFPA, injury, radiotherapy, inflammatory
- Investigations: tfts/prolactin/gh/lh/fsh, mri brain with contrast, visual field testing, insulin stress test (GH/cortisol should suppress but they don’t - can’t do this if epilepsy/isch hd/adrenal insuff)
- Management: if NFPA transphenoidal removal, hydrocort, gh, thyroxine, test/oest
- pituitary apoplexy: sudden enlargement of NFPA due to haemorrhage or infection. Can be precipitated by htn/preg/trauma/anticoag. Leads to sudden onset headache, vomit, neck stiff, bitemp sup quad, nerve palsies. Needs MRI and urgent steroid replacement + surgery
Hyperprolactinaemia:
- function
- Causes (5)
- microprolactinom vs macroprolactinoma
- symptoms
- ix
- mx
- other causes of galactorrhoea
Hyperprolactinaemia:
- function of prolactin: stims breast development, stims milk production, blocks lh. Inhibited by dopamine
- Causes (5): prolactinoma (a pituitary adenoma), antiemetics/antipsychotics, preg, pcos
- microprolactinoma vs macro: <1cm prolactin <1000 vs >1cm and >5000
- symptoms: menstrual irreg/infert/osteoporosis/galactorrhoea, in men loss libido + galactorrhoea, headache, bitemp superior quadrantopia, other hypopit symptoms
- ix: mri
- Management macroprolactinoma: dopamine agonists cabergoline/bromocriptine which inhibits prolactin release from ant pit gland (SE: nausea, postural hypotension, psychosis), transphenoidal surgery
- galact: preg, oest, acromegaly, pcos, metoclop
- Investigations for the pituitary gland
- Examples of functional pituitary tumours
- Investigations for the pituitary gland: prolactin, tfts, lh/fsh 1st 5 days of menstrual cycle, 9am test, 9am cortisol, gh/igf1, synacthen test, insulin tolerance test
- Examples of functional pituitary tumours: tshoma, prolactinoma, cushings disease, acromegaly
Hyperthyroidism:
- Other name and definition
- Thyroid hormone function
- Causes (5)
- Symptoms (8)
- Signs (7)
- Investigations
- Management
- Complications
- Subclinical hyperthyroidism
- hashimotos thyroiditis
- Other name and definition: thyrotoxicosis, t4 thyroxine, t3 triiodothyronine
- thyroid hormone function: inc sns (hr etc), catabolic pathways (lipolysis, glucose uptake, gluconeogen)
- Causes (5): graves (igG tshrec ab), thyroiditis, post partum thyroiditis, lithium/amiodarone
- Symptoms (8): diarrhea, restless, anxiety, weight loss, heat intolerance, menstrual disturbance
- Signs (7): palpitations/tachycardia, warm extremities, fine tremor, hyperreflexia, exophthalmus (gravees), lid lag (inc sns tone), lid retraction (graves), pretibial myxoedema (graves), thyroid acropachy (graves - digital clubbing, hand/feet soft tissue swelling, periosteal new bone formation)
- Investigations: tfts, thyroid peroxidase, tshr ab, uss thyroid, thyroid scintigraphy (in graves homogenous increased uptake radioactive iodine)
- Management: carbimazole 12-18 months (blocks thyroid peroxidase - agranulocytosis, rash, hepatitis, pancreatitis, crosses placenta) but takes 4-6 weeks, propranolol initially until controlled, radioiodine therapy (not if preg, <16), total thyroidectomy
- Complications: thyroid storm (precipitated by thyroid surgery/trauma/infection - fever, tachyc, confusion, n+v, htn - need iv fluids, iv propranolol, hydrocortisone, propylthiouracil)
- Subclinical hyperthyroidism: t3/t4 normal but tsh low - caused by goitre, or excessive thyroxine. Can cause AF + osteoporosis.
Hypothyroidism
- Causes (7)
- Symptoms (7)
- Signs (2)
- Investigations
- Management
- Subclinical hypothyroidism
Hypothyroidism
- Causes (7): hashimotos thyroiditis (autoimmune destruction, transient hyperthyroidism in acute phase), radiation, thyroidectomy, subacute thyroiditis (dq quev), diet loss iodine, secondary (downs, coeliac, turners)
- Symptoms (7): constipation, moody, dry hair/skin, weight gain, hair loss, fatigue, cold, menorrhagia
- Signs (2): bradycardia, carpal tunnel
- Investigations: tfts, anti thyroid peroxidase ab (hashi), anti thyroglobulin, thyroid uss
- Management: levothyroxine (over replacement inc risk osteoporosis)
- Complications: hashimotos inc risk of MALT lymphoma, myxoedemic coma (thyroxine + hydrocortisone, iv fluids, steroids stop conversion of t4-> t3)
- Subclinical hypothyroidism: tsh inc, t3/4 normal. If tsh>10 on 2 sep occasions 3 months apart then give levothyroxine. If <65 yrs and levels between 5.5-10 and symptoms then 6 month trial. If assymp or older just wait and retest in 6 months
- Congenital: prolonged jaundice, delayed milestones, macroglossia, short, hypotonia
- sick thyroid syndrome: low t3/4, normal tsh - just need recovery from systemic illness
- de quervains: follows viral infection. first few weeks hyperthy signs then hypo for a few months. Self limiting, nsaids if pain
Primary adrenal insufficiency:
- Other name
- Describe areas of adrenal cortex and what they produce
- Definition
- Symptoms (6)
- Signs (4)
- Investigations
- Management
- Complications
- Describe 2ndary adrenal insufficiency
Primary adrenal insufficiency:
- Other name: addisons disease
- Describe areas of adrenal cortex and what they produce: glomerulosa (mineralcorticoids: aldosterone), fasciculata (glucocorticoids: cortisol), reticularis (androgens), adrenal medulla: na/ad
- what does cortisol do: inc protein breakdown, lipolysis, gluconeogenesis, antiinflammatory, inhibits bone formation
- Definition: autoimmune destruction of adrenal glands means no oest/test, no cortisol and no aldosterone
- Symptoms (6): reduced libido, weakness/fatigue, n+v, abdo pain, decreased weight
- Signs (4): dec pubic hair, postural hypotension, increased skin pigmentation, hypoglycemia
- Investigations: u+es/hba1c/vbg (metab acidosis), low cortisol morning, acth stimulation test (short synacthen test - (cortisol doesn’t increase so means there is an issue with adrenal gland) definitive
- Management: hydrocortisone (majority in morning, rest in evening), fludrocortisone - if ill double hydrocortisone but keep flud dose same, steroid emergency card
- Complications: addisonians crisis (due to sepsis/surgery/steroid withdrawal - needs iv hyd 6 hourly until pt stable + fluids) - nausea, confusion, fever, headache, weakness
- Describe 2ndary adrenal insufficiency: when its not a problem with adrenal glands but hypopituitism
Phaeochromocytoma:
- Definition
- Symptoms (3)
- Signs (7)
- Complications
- Investigations
- Management
Phaeochromocytoma:
- Definition: adrenal medulla tumour in chromaffin cells secreting catecholamines NA/AD (if not medulla then paraglioma). Part of men (+ thyroid ca, insulinoma)
- Symptoms (3): headache, sob, panic attacks, palpitations
- Signs (7): sweating, pallor, htn
- Complications: htn crisis, arrhythmia, pul oedema, hyperglycemia, encephalopathy
- Investigations: 24 hour urine metanephrines, ct abdo
- Management: adrenalectomy, alpha blockade phenoxybenzamine then b blocker
Whilst awaiting treatment: labetalol
Hyperaldosteronism:
- function aldosterone
- Primary causes
- Secondary causes
- Investigations
- Symptoms
- Management
Hyperaldosteronism:
- function aldosterone: if low circ bp/hyponat/hyperkal means renin released which converts angiotensinogen to ang 1->2 via angiotensin converting enzyme whih stims aldosterone release which acts on DCT nak pump to increase na retention
- Primary causes: conns (adrenal adenoma), bilat idiop adrenal hyperplasia (most common), familial, adrenal carcinoma - renin is reduced due to neg fb of inc bp
- Secondary causes: renal art stenosis, hf, nephrotic syndrome - renin is increased
- Investigations: bp, u+es, renin: ald ratio plasma first line, HRCT abdo + adrenal vein, vbg (metabolic alkalosis)
- Symptoms: headache/burry vision/nosebleeds, stroke, hypoka (muscle weakness), hypernat symptoms
- Management: spironolactone if bilat adrenal hyperplasia, adenoma removal, renal art angioplasty
Congenital adrenal hyperplasia:
- definition
- cause
- symptoms
- ix
- mx
Congenital adrenal hyperplasia:
- definition: auto recessive where impairment adrenal steroid synthesis leading to inc ACTH leading to increase in androgens
- cause: 21a hydroxylase deficiency, 11b hydroxylase deficiency
- symptoms: female ambig genitalia, precocious puberty, infertility, accelerated growth but shorter adult stature, salt wasting crisis (dehydration, hypotension, electrolyte imbalances),
- ix: acth stim test -
- mx: glucocorticoid replacement
Corticosteroid:
- SE
Pred = glucocorticoid
SE:
- hyperglycemia
- increased appetite
- cushings syndrome
- osteoporosis
- avn femoral head
- insomnia
- psychosis
- suppresses growth in children
Gradual withdrawal if >40mg pred, >3 weeks
Fludro = mineralcorticoid
SE:
- htn
- fluid retention
Disorders of sex development
- androgen insensitivity
- 5a reductase deficiency
- klinefelters
- kallmann
Disorders of sex development
- androgen insensitivity: 46xy - x linked recessive. means resistance to testosterone so female phenotype - vagina and testes present, no uterus. Test/LH/Oest elevated
- 5a reductase deficiency: 46XY - auto recessive. means males can’t convert test -> dihydrotest - ambiguous genitalia, hypospadius
- klinefelters: 47xxy - tall, long limbs, lack secondary characteristics, small testes, infertile, gynaecomastia hence inc risk breast ca, elevated lh/fsh but dec test
- kallmann: hypogonadotrophic hypogonadism x linked recessive - lack smell, delayed puberty, test/lh/fsh low - need test supplements
Gynaecomastia causes:
- androgen deficiency causes e.g. klinefelters
- liver disease
- testic ca
- hyperthyroidism
- drugs: spironolactonee, digoxin, finasteride
Insulinoma:
- definition
- symptoms
- ix
- mx
Insulinoma:
- definition: neuroendocrine tumour from pancreatic islet cells langerhans, if multiple tumours 50% MEN1
- symptoms: hypoglycaemia in early morning/just before meal, rapid weight gain, high insulin, high c peptide
- ix: supervised prolonged fasting up to 72 hours, ct pancreas, when giving insulin c peptide levels dont fall
- mx: surgery, diazoxide and somatostatin if no surgery
