Adrenal/steroids Flashcards
When does physiological cortisol peak?
6-9am
Which factors have a positive feedback on cortisol production?
stress, Adr/NA, ghrelin
Which drugs have a negative feedback on cortisol production?
opioids
Which autoantibodies exist in >90% of addison’s patients?
21-hydroxylase
Which complications of addison’s disease should you be wary of?
Other autoimmune conditions, e.g. vitligo, coeliac disease, adrenal crisis
What are triggers for adrenal crisis?
acute stress, infection, haemorrhage
How to clinically distinguish primary adrenal insufficiency from secondary and tertiary? (signs)
no hyperpigmentation and no dehydration in 2+3
What would be the initial management plan for someone with suspected hypoadrenalism?
IV fluids, IV hydrocortisone, DVT prophylaxis, antiemetic
What are the causes of hypoadrenalism?
- Infections (TB, meningococcal)
- Drugs
- Metastatic destruction of adrenal glands
- Congenital adrenal hyperplasia
What is the protocol for short synacthen test?
- Ensure no glucocorticoid therapy given that morning
- Early morning ACTH and cortisol levels taken
- Dose of synthetic ACTH 250 micrograms
- Blood taken 30 min post ACTH
Which condition that arises in pregnancy can result in adrenal insufficiency?
Sheehan syndrome. life-threatening amount of blood in childbirth or who have severe low blood pressure during or after childbirth, which can deprive the body of oxygen. This lack of oxygen that causes damage to the pituitary gland
Which drug prescription can induce adrenal insufficiency?
steroids
In secondary and tertiary adrenal insufficiency, are mineralcorticoids still produced?
yes
Which is the most common cause of adrenal insufficiency in children?
congenital adrenal hyperplasia
What happens to the levels of Na and K in adrenal insuffiency?
Decreased Na and incr K
Why does bronzing occur in primary adrenal insufficiency?
ACTH stimulates melanocytes
Name two symptoms of adrenal insuffiency
muscle cramps, N/V
What is the treatment for adrenal insufficiency?
hydrocortisone and fludrocortisone
Is fluodrocortisone necessary in secondary and tertiary adrenal insufficiency?
unnecessary
If a patient with addison’s disease is sick, how should this affect their routine medications?
double dosage of corticoseroids but maintain the fludrocortisone dose
Two catabolic effects of cushing’s syndrome
Proximal myopathy
Striae
Bruising
Osteoporosis
Two glucocorticoid effects of cushing’s
DM
obesity
Two mineralcorticoid effects of cushing’s?
HTN
hypokalaemia
Describe three features of the appearance of someone with cushing’s
Moon face Acne and hirsutism Interscapular and supraclavicular fat pads Centripetal obesity Striae Thin limbs Bruising Thin skin
How is cushing’s syndrome categorised/divided?
ACTH independent
ACTH dependent
Two differentials for ACTH independent cushing’s?
Iatrogenic steroids: commonest cause
Adrenal adenoma / Ca: carcinoma often → virilisation
Adrenal nodular hyperplasia
Two differentials for ACTH dependent cushing’s?
cushing’s disease
ectopic-ACTH
An example of ectopic-ACTH cause?
SCLC
Carcinoid tumour
Two investigations for cushing’s syndrome?
24hr urinary free cortisol
Late night serum or salivary cortisol
Dexamethasone suppression test
ACTH
Which condition would show cortisol suppression in dexamethasone suppression test?
cushing’s disease only
Explain the dexamethasone suppression test
low dose test- confirms cushing’s syndrome
high dose test
-low cortisol= cushing’s disease
- high cortisol- high ACTH= ectopic ACTH, low ACTH= adrenal cushings, iatrogenic
What is cushing’s disease?
pituitary adenoma producing excess ACTH
What is conn’s syndrome?
adrenocorticol adenoma
Two causes of primary hyperaldosteronism?
bilateral adrenal hyperplasia
adrenocortical adenoma= conn’ syndrome
Which biochemical abnormality is present in hyperaldosteronism?
hypokalaemia
Two causes of secondary hyperaldosteronism?
diuretics nephrotic syndrome hepatic failure CCF RAS abnormalities
Brief pathophysiology of hyperaldosteronism?
increases renin concentration due to reduced renal perfusion
How can you distinguish between primary and secondary hyperaldosteronism?
aldosterone: renin ratio
Raised in primary
Normal in secondary
Two symptoms of hyperaldosteornism?
HTN
weakness, hypotonia, cramps- hypokalaemia
What are the effects of aldosterone?
increases expression in Na/K ATPase and eNaC following steroid receptor activation which results in the transcription of these channels in the distal convoluted tubule (and collecting duct)
Patient has very high aldosterone but low renin. What might be the diagnosis?
primary aldosteronism
What is the most common cause of secondary hypertension?
primary aldosteronism
Which test is employed to test aldosterone levels/function?
saline suppression test, if aldosterone levels are still high then very suspiscous of primary aldosteronism as aldosterone levels should be reduced
Three causes of primary adrenal insufficiency?
Autoimmune destruction: 80% in the UK
TB: commonest worldwide
Metastasis: lung, breast, kidneys
Congenital: CAH
Three symptoms of primary adrenal insufficiency?
Wt. loss + anorexia
n/v, abdo pain, diarrhoea/constipation
Lethargy, depression
Hyperpigmentation: buccal mucosa, palmar creases
Postural hypotension → dizziness, faints
Hypoglycaemia
Vitiligo
Addisonian crisis
Two abnormal findings in blood tests of primary adrenal insufficiency
hypoglycaemia
hyponatraemia, hyperkalaemia
hypocalcaemia
Which autoantibody is present in primary adrenal?
21-hydroxylase
Which is the main diagnostic test for addison’s?
short synACTHen test
Treatment for addison’s?
hydrocortisone
fludrocortisone
Name two pieces of advice to offer adrenal insufficiency patient
don’t stop steroids suddenly
increase dosage of steroids during injury, illness
wear a medic-alert bracelet/have emergency info on phone
Two causes of secondary adrenal insufficiency?
chronic steroid use
Sheehan’s
Pituitary microadenoma
What is Sheehan’s syndrome?
Excessive blood loss during or after delivery of a baby may affect the function of the pituitary gland, leading to a form of maternal hypopituitarism
How to distinguish between primary and secondary adrenal insufficiency?
Normal mineralcorticoid in secondary
No pigmentation in secondary
Two clinical features of addisonian crisis?
shock- tachy, oliguria, confused, postural drop
hypoglycaemia
State one hereditary association of phaechromocytomas?
MEN2a and 2b
Three seminal features of phaechromocytoma presentation?
episodic headache, sweating, tachycardia
Two investigations for phaechromytoma?
Abdo CT and plasma + urine metadrenaline
Prior to adrenlectomy for phaeochomocytoma, what must be given pre-op?
alpha blocker first, then beta blocker pre-op
Emergency presentation of phaechromocytoma?
hypertensive crisis
Three causes of hypopituitarism?
Tumour, inflammation, infection, ischaemia, trauma of hypothalamus, pituitary stalk, or pituitary gland
Two common causes of panhypopituitarism?
surgery
tumour
irradiation
Name three hormone deficiencies that arise in hypopituitarism?
GH
LH/FSH
TSH
ACTH
Three causes of hyperprolactinaemia?
lactation pregnancy prolactinoma pituitary adenoma antiemetics: metoclopramide antipscyhotics: haloperidol (physiological, pituitary, pharmacological)
Three symptoms of hyperprolactinaemia?
Amenorrhoea
Infertility
Galactorrhoea
↓ libido
Patient is exhibiting symptoms of hyperprolactinaemia. The result of their basal prolactin test is 5907. What is the diagnosis?
prolactinoma >5000
Three investigations for hyperprolactinaemia?
Pregnancy test
TFTs
Serum prolactin
MRI
What is the treatment for hyperprolactinaemia?
DA agonist- cabergoline or bromocriptine
What is the number one cause of acromegaly?
pituitary adenoma
Three symptoms of acromegaly?
Acroparaesthesia Amenorrhoea, ↓libido Headache Snoring Sweating Arthralgia, back ache Carpal tunnel (50%)
Four signs of acromegaly?
Hands- thenar wasting, increased skin fold thickness
Face- goitre, widely spaced teeth, wide nose, big ears, prominent supraorbital ridges
Two complications of acromegaly?
Impaired glucose tolerance DM HTN Cardiomyopathy Increased risk of IHD and stroke
Why does hyperglycaemia arise in acromegaly?
GH fails to suppress glucose in acromegaly
Two blood results of acromegaly?
Incr IGF1, incr glucose, ca, and PO4
Two features of clinical presentation of PCOS
symptoms of anovulation- amenorrhoea, oligomenorrhoea, irregular cycles
hyperandrogenism- hirsutism, acne, alopecia.
Which hormones are raised in PCOS?
testosterone and LH
Which endocrine disorder does PCOS increase the risk of?
type 2 diabetes
What are the three components of POS pathophysiology?
gonadotrophins, androgens, insulin resistance
Which androgens are raised in PCOS?
testosterone, androstenedione, DHEAs
What is the major source of androstenedione in women?
ovary
What about DHEA-S?
adrenal gland
Which hormone will be able to tell you whether the abnormal androgen production is in the ovary or adrenal?
DHEA-S as 95% of this is produced by the adrenal, while testosterone androstenedione are produced in the adrenal gland AND ovary in equal-ish amounts
Testosterone is only biologically active when free. If there is increased production in PCOS, is there increased binding globulins?
reduced binding globulin, therefore more free androgens, leading to symptoms of PCOS
What is the main binding globulin for androgens?
SHBG
Which diabetes treatment can be used to treat PCOS?
metformin, improves insulin sensitivity and therefore leads to a decrease in LH levels, increases in SHBG, and decreased free androgens
What is the most effective treatment for PCOS symptoms?
calorie restriction
Which form of testosterone is biologically active?
free testosterone
Which enzyme converts testosterone to oestrogen?
aromatase
How does hypogonadism present in male child/young adult?
slow growth in teens, no growth spurt, small testes and phallus, lack of secondary development
How does hypogonadism present in adults?
depression/low mood, poor libido, erectile problems, poor muscle, sparse body hair, gynoid weight gain
What is gynoid weight gain?
weight around the chest, hips, and thighs
Once a history suggests hypogonadism, which tests should be done?
- Testosterone- free, early, SHBG 2. FSH and LH. 3. Semen analysis
Why would you want to measure LH and FSH in hypogonadism?
to rule out pituitary involvement
In general, what are the two sources of causes for hypogonadism?
- Hypothalamic-pituitary 2. Testicular problem
If you suspect hypogonadotrophic hypogonadism as there is low testosterone and low FSH+LH, which further tests should you do and why?
prolactin, cortisol, TSH…to ensure the whole pituitary is working
Three causes of hypogonadotrophic hypogonadism?
- pituitary tumour 2. Genetic syndromes 3. Surgery 4. Head injury 5. Cerebellar ataxia 6. Kallmann’s syndrome
15 y/o male with poor sense of smell, poor hearing, and impaired growth, what is the likely diagnosis?
Kallmann’s syndrome
What would the levels of testosterone, LH/FSH, and prolactin be in primary gonadal disease?
low test, normal/high FSH/LH, normal prolactin
Three differentials for primary gonadal disease?
1 Kleinefelter’s
2 trauma/chemo/radiotherapy can lead to seminiferous tubule and leydig cell failure
3 cryptorchodism
What is the most common genetic cause of male hypogonadism?
Klinefelter’s syndrome
How does Klinefelter’s present clinically?
wide clinical variation in phenotype due to hormonal respone to LH surges. In general, delayed puberty, suboptimal genital development, reduced secondary male sexual characteristics, behavioural difficulties
Two treatments for hypogonadism in males?
androgen replacement therapy, fertility treatment