Endocrinology Flashcards
(70 cards)
1
Q
Which hormones are released by anterior pit
A
FLAT GP FSH LH ACTH TSH GH Prolactin
2
Q
Which hormones are released by post pit
A
Oxytocin
ADH
3
Q
Describe the thyroid axis
A
Hypothalamus releases TRH
Ant pit releases TSH
Thyroid releases T4-> T3
4
Q
Symptoms of hypothyroidism
A
- Weight gain
- Fatigue/weakness
- Cold
- Depression
- Hair loss
5
Q
Causes of hypothyroidism
A
- Autoimmune (hashimotos, atrophic)
- Treatment of hyper (iodine, surgery)
- Natural course of thyroiditis and graves
- Drug (amiodorone, lithium, phenytoin)
- Central - hypopituitarism
WORLDWIDE = iodine deficiency
6
Q
Diagnosis of hypothyroidism
A
- TSH high
- T4 and T3 low
MAY SEE
TPO antibodies raised
7
Q
Treatment of hypothyroidism
A
100-150mcg Levothyroxine or 25 for elderly/IHD
Rare SE
interacts with warfarin
8
Q
Symptoms of hyperthyroidism
A
Weight loss/inc appetite Heat intolerance/sweating Fatigue/cant seep tremor Palpitations/nervousness Irregular periods Eye problems
9
Q
Causes of hyperthyroidism
A
- Graves disease
- TNG
- Thyroiditis (autoimmune or viral)
- Drug induced (amiodarone)
- Iodine induced Jod basedow
10
Q
Diagnosis of hyperthyroidism
A
- Low TSH
- High T4/3
MAY SEE
anti TSH antibodies (TRab)
11
Q
Treatment of hyperthyroidism
A
GRAVES - long course carbimazole 20mg 1 daily - radioiodine TNG - radioiodine - surgery -long term carbimazole
BRIDGE = beta blocker for 1st month propanolol = mild nadolol = severe
12
Q
Graves disease natural history, presentation and assd conditions
A
strong genetic asscn
Spontaneous remission 1-2 yrs common. then long term remission, R+R, hypo (TRab)
Can present with dermopathy, smooth diffuse goitre, eye signs assd with smoking
ASSD with addisons, pernicious anaemia and vitiligo
13
Q
RF for hyperthyroidism to elicit in history
A
- FH of autoimmunity
- Female
- Smoking
if post partum thyroiditis suspected ask about t1 diabetes
14
Q
Describe hypothalamic- adrenal axis (EDIT)
A
hypothalamus releases ARH
Ant pit releases ACTH
Adrenal glands release cortisol and androgens
15
Q
Functions of cortisol
A
- Stress response- alert
- Inc blood glucose
- Inc metabolism
- Suppress immune response
- Suppress bone formation
16
Q
Causes of primary adrenal insufficiency
A
- Autoimmune = Addison’s disease
- Infective = TB, HIV
- Congenital = CAH
- Neoplastic = adrenal, mets from RCC, lung
- Non malignant infiltration = sarcoidosis, amyloidosis, haemochromatosis
17
Q
Symptoms of primary adrenal insufficiency
A
Low aldosterone: - fatigue, weakness - orthostatic hypo Abdo signs: - weight loss - N/V - abdo pain
XS ACTH = hyperpigmentation
TANNED TIRED TEARFUL TUMMY
18
Q
Causes of Cushing syndrome
A
- Cushing disease = acth secreting pituitary adenoma
- Exogenous steroids= long term tx
- Ectopic source = paraneoplastic syndrome eg SCLC ACTH secreting
- Cancer- Adreno-cortical carcinoma
19
Q
Growth hormone axis
A
Hypothalamus releases GHRH
ant pit releases GH
Liver releases insulin like growth factor 1 IGF1
IGF1 acts everywhere - bone density, muscle mass, cell turnover and organ growth
20
Q
What is function of somatostatin
A
Growth hormone inhibiting hormone
21
Q
What is ghrelin
A
Hormone released by digestive organs onto Ant pit to stimulate GH release
22
Q
Describe PTH axis
A
- Low calcium, low magneisum and high P04 cause PTH release from 4 glands on thyroid
- Inc in number and activity of osteoclasts -> Ca release
- Kidneys reabsorb calcium
- Kidneys activate vit D -> inc calcium absorption from food in gut
23
Q
Describe PTH axis
A
- Low calcium, low magneisum and high P04 cause PTH release from 4 glands on thyroid
- Inc in number and activity of osteoclasts -> Ca release
- Kidneys reabsorb calcium
- Kidneys activate vit D -> inc calcium absorption from food in SI
24
Q
Describe RAAS
A
- low circ volume detected
- renin released from kidney
- acts on angiotensin 1 (liver)-> 2
- angiotensin 2-> angitoensinogen by ACE
- angiotensinogen causes vasoconstriction and aldosterone release (adrenal)
- aldosterone = water and Na reaborsption DT and H,K secretion?
25
Carbimazole indication, SE and alternative
Used to control Graves, TNG
Works by blocking TPO from organifying the iodine
RISK = agranulocytosis = low neutrophils = check fbc in pxs on this drug when ill
SE- rash, GI
Teratogenicity
Alternative in preg esp 1st trimester: propylthiouracil
SE: hepatotoxicity and fulminant hepatitis
26
How does thyroid cancer present, diagnosis, treatment
Asymptomatic, palpable nodule in 30-40 year old women
risk - previous head /neck radiation
Diagnose: USS and FNAC
Tx: thyroidectomy, radioiodine ablation, TSH suppressing dose of levothyroxine
rare but good prognosis for most types
27
Role of steroids in thyroid problems
If treating px with thyroid eye disease with radioactive iodine need to give prophylactic steroids
Can give prednisolone in severe thyroiditis symptom management
28
What is T1 diabetes
Autoimmune or idiopathic destruction of beta cells that result in complete loss of insulin
So there is no uptake of glucose from blood, no glyconeogenesis, no inhibition of glycogenolysis
29
Diagnosis of diabetes
HbA1c > 48
Fasting bgc > 7
Random bgc or OGTT > 11
If T1 symptomatic = 1 test is enough
if T2 need 2 tests
30
Diagnosis of pre-diabetes
HBA1c > 38
Fasting > 5.5
Random > 7.8
31
Treatment of T1 diabetes
Insulin injection or subcut infusion
Never stop, inc when ill (hyperglycaemic)
Take a mixture of long and short acting
Monitor 3 monthly with Hba1c or fructosamine if blood disorder
32
What is DKA
1. Hyperglycaemic or known diabetic
2. Ketonaemia >3 bloods or urine >2
3. Metabolic acidosis VBG > 7.3 pH or Hc03 <15
Cause
- forgot to take insulin/infection
33
Presentation of DKA
```
ACUTE < 24 HOURS
T1 DIABETIC
Usual t1 symptoms +
N+V
Abdo pain
Reduced conciousness,low bp, excessive tiredness, headache
Hyperventilation
Hot dry skin
Hypothermic
```
34
Presentation of DKA
```
ACUTE < 24 HOURS
T1 DIABETIC
Usual t1 symptoms +
N+V
Abdo pain
Reduced conciousness,low bp, excessive tiredness, headache
Hyperventilation
Hot dry skin
Hypothermic
```
35
Treatment of DKA
1. 500ml of 0.9% NaCL
2. FRII 0.1unit/kg/hour of insulin
3. Potassium if <5.5 because insulin lowers K risk of hypokalaemia
4. VTE prophylaxis
5. Glucose if bgc <14
36
What is T2 diabetes
Beta cell of pancreas dysfunction = reduced sensitivity to and production of insulin
37
Presentation of T2 diabetic
Asymptomatic
| Chronic fatigue, may have blurred vision
38
RF for T2 diabetes
Non modifiable:
- age
- ethnicity
- FH
- PCOS
- exisitng CVD
Modifiable:
- activity, weight status (BMI 25-30 over, 30+ obese)
- hypertension
- hyperlipidaemia
39
Management of T2 diabetes other than OHA
```
Conservative:
activity = reduce cv risk, directly use glucose, inc glycogen stores, directly inc sensitivity to insulin
change diet
stop smoking = cvd
alcohol = risk hypo
```
DRUGS
- BP
- Lipid
- Antiplatelet asprin, clopidogrel CV risk
40
What is HHS
1. Hyperosmolar ( >320 mosmol/kg)
2. Marked Hyperglycaemic (>30)
3. Hypovolemic
4. non ketotic
Causes - old diabetic who is ill or poorly controlled
Present - confused, dehydrated over a few days
41
Treat HHS
SLOW fluid replacement, naturally lowers glucose
if not -> insulin
Watch for hypernatraemia with saline replacement
Watch for hypokalaemia
VTE and ulcer protection
42
OHA for T2 diabetes
1. Metformin
2. SU eg gliclazide
3. Pioglitazone
4. Incretin based - gliptins, exenatide
5. Acarbose
6. SGLT2 inhibitors
43
How does metformin work, benefits and SE
Increases insulin sensitivity by
- inc glucose uptake into muscle
- reduce gluconeogensis
- decrease gut absorption of glucose
Benefit: cannot cause hypo or weight gain
BUT risk of lactic acidosis so check LFT and U+E before.
SE- GI, impaired B12 absorption
44
How do SU's work, examples, side effects.
| Name a similar drug
Change electrochemical gradient accross B cells via K = MORE INSULIN secreted
EG gliclazide, tolbutamide (s), glibenclamide (l)
SE- hypo, weight gain
CI- pregnancy/breastfeeding
SIMILAR- REPAGLINIDE
but shorter half life, less risk of hypo
45
What is pioglitazone an example of, how does it work and what are its SE
Thiazolidinediones
Increases lipid metabolism -> secondary glucose uptake
SE- weight gain, peripheral oedema, inc risk bladder cancer, reduce bone density
46
How do gliptins work, examples, SE
```
Gliptins = inhibit DPP4 = inhibit incretin(GLP1) breakdown
= inc glucose mediated insulin release
SE- pancreatitis
CANT cause hypo
Eg
Linagliptin, Alogliptin, Saxagliptin
```
47
What kind of drug is exanatide, how does it work for diabetes and SE
Exanatide is a GLP1 analogue (mimetic) = glucose mediated insulin release increases
also : impaired glucagon secretion, slow gastric emptying
Benefit = only one good for obese px except acarbose
SE- subcut injection, N+V, pancreatitis
48
How do SGLT2 inhibitors work for diabetes, examples, SE
Reduce renal resorption of glucose
Gliflozins
SE- DKA, peripheral vasc disease
Eg dapagliflozin, clanagliflozin
49
Risk factors/associations of primary adrenal insufficiency
1. Hypothyroidism
2. Female
3. Hypercoaguable state
50
Symptoms of Cushing’s syndrome
1. Central adiposity, buffalo hump
2. Purple striae
3. Think skin, bruising
4. Facial plethora
5. Diabetes symptoms
6. Prem osteoporosis
51
How to investigate cushing syndrome
PMH: steroid use, cancers
DEXAMETHASONE suppression test
Low dose = fails to suppress axis, cortisol still high
High dose = lowers cortisol in cushings disease. Ectopic or endogenous = stay high.
MRI pituitary for disease
52
How is cushings syndrome treated
DISEASE: trans-sphenoidal hypophysectomy, radiotherapy
SYNDROME: metyrapone, ketoconazole, etomidate ICU, mitotane (ACC)
53
How is primary adrenal insufficiency diagnosed
Low sodium, high potassium
SHORT SYNACTHEN TEST
primary = low or no cortisol response
54
How is secondary adrenal insufficiency diagnosed
high suspicion -> treat
Early morning cortisol
May do a synacthen if stable later
55
How is adrenal insufficiency treated
1. Replace aldosterone if primary = fludrocortisone
| 2. Replace cortisol = hydrocortisone
56
What is an adrenal crisis and how is it prevented
```
Emergency situation where a patient has insufficient cortisol response to stress
They will be
- hypotensive, tachycardic
- hypoglycaemic
- hyponatraemic -> confused
hyperkalaemic
```
PREVENT = sick day rules, pxs on cortisol should take more when ill
57
Causes of secondary adrenal insufficiency
1. Exogenous steroid use
2. Ectopic ACTH secretion
3. Hypopituitarism
58
What are the causes of primary hyperaldosteronism/Conn's syndrome?
1. Aldosterone secreting adenoma of adrenals
| 2. Idiopathic (familial)
59
How does Conn's present
1. Hypertensive (always consider)
- headaches
- retinopathy
- weakness/tired
2. Hypokalaemic (can be normal, but they can end up swapping H,K for Na)
risk of met acidosis
could also present with hypertensive complications eg stroke
60
Diagnosis of conn's
1. Plasma aldosterone: renin ratio= increased
| 2. Fludrocortisone suppression test = would expect aldosterone to drop but it doesn't
61
How is conn's treated
1. Excise adenoma
| 2. Spironolactone (gynae SE), triamterene for K preservation + amiloride diuretic for fluid overload
62
What is phaeochromocytoma
Excess catecholamines (ad,nad, dop) due to adrenal medullary tumour
63
Symptoms of phaeochromocytoma
random
- sweating
- palpitation
- headache
-tremor
-pallor
- weakness
hypertension
64
How is phaeochromocytoma diagnosed + tx
No consensus for diagnostic test
| Tx- alpha and beta blockers, excise tumour
65
Causes of secondary hyperaldosteronism
- Benign JMA growth = inc renin
| - RAS = false activation
66
Causes of primary hyperparathyroidism and blood results
1. benign PT adenoma
2. Hyperplasia
3. Cancerous tumour
PTH high
Calcium high
Phosphate low
vit d high
67
Causes of secondary hyperparathyroidism and blood results
1. renal disease
2. vit d deficiency
3. malabsorption eg pancreatitis
PTH high
calcium low
Phosphate high
low vit d (renal fail)
68
Causes of tertiary hyperparathyroidism and blood results
```
Continued secondary, px given tx but axis doesnt respond
PTH high
calcium high
phosphate high
vit d low
```
69
Symptoms of hypercalcaemia
Stones
Bones
Abdo moans
Pyschic groans(confusion)
70
Symptoms of hypocalcaemia
```
CATs go numb
convulsions
arrhythmias
tetany
numb hands, feet, around mouth
= chvosteks sign
= trosseau sign
```
