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Flashcards in Endocrine Deck (78)
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1

How to Dx. Di

1. 8 hwater deprivation test
Normal > 600mmols/l
DI - <300 mmil/l

2. Desmopressin 2 mg IM IV
Central - > 800 mmols/l
Nephrogenic - no correction

2

What is the plasma and urine osmolarity in DI

plasma osmolarity is HGIH
urine osmolarity LOW

3

Na levels in DI and clinical findings

HYPERNATREMIA
- lethargy
- confusion
- coma
- fits

4

Ddx DI

DM
polyuria
psychological
DIURETICS
LITHIUM
PROSTATIC HYPERTROPHY

5

Screening for cause DI

Centra: MRI and pituitary function test

Nephroenic
- U/E
- Calcium
- Renal ULTRASOUND

6

Treatment for DI

Centra - mild - increase fluid intake
moderate- desmopressin and DDAVP (at lowest dose to control symp)

Nephrogenic - tx underlying disease
Diuretics - BENDOFLUMETHIAZIDE and NSAIS (prostaglandin inhibits Na )

7

side effect DDAP

can worsen MI in susceptible patients
Hyponatremia

8

untreated DI

hypernatremia
CV collapse
dehydrate
death

9

complications of acromegaly
vle

Heart : HTn , CM , LVH , HF
Pancreas: DM
Lungs: sleep apnea , pulm HTN
Arthritis
Neuro - HEADACHE , cerebral vascular events
MISCILLANEOUS
- carpal tunnel
- colon polyps/ Ca
Hypopituitarism
Pyperprolactinemia
Carpel tunnel

10

DI screening test

Elevated serum IGF-1 levels

11

DI diagnostic test

OGTT
GH is normally inhibited by glucose
2 baseline GH levels after fasting for 8 hours
Ingestion of 75g of oral glucose
GH measurement at 30, 60, 90, 120mins post oral glucose load
Active acromegaly

12

Di cause tests

Pituitary Anatomy
MRI pituitary: show micro or macro adenoma

CT scan: thorax, abdomen, pelvis
Non-endocrine tumours / ectopic GH secretion

13

Screening complications

Anterior pituitary function tests:
Decreased Serum TSH ACTH and Cortisol
Reduced Serum LHRH, LH, FSH, testosterone
Raised Serum prolactin

ECG . BP, CXR - heart failure signs cardiomegaly
Sleep studies (sleep apnea)
CoLONSCOPY
DM - screen

14

dx test chushings

Random cortisol (not helpful usually as peaks & troughs throughout day & varies due to stress, illness,etc)

24 hour urinary free cortisol: HIGH
Midnight cortisol- high

Overnight dexamethasone suppression test
- 1mg dexamethasone at midnight
do cortisol level at 8am - normal should decrease if not low then CS

24 hour dexamethasone suppression test

15

Screening for cushing cause

Where is the lesion?
Plasma ACTH: If undetectable- likely adrenal cause → CT adrenal

Plasma ACTH: if detectable-
Do corticotrophin releasing test
Cortisol rises - pituitary cause -- > BRAIN MRI then inferior petrosal sinus sample
ectopic ACTH does’t else

16

riASeD BP and hypokalemia

Primary hypoaldosteronism

17

treatment Conns

Treat underlying cause
Hypokalaemia: IV potassium replacement via slow infusion
Conn’s syndrome:
Laparoscopic adrenalectomy
Spironolactone for 4 weeks pre-op for BP & K+ control
Hyperplasia
Treat medically with aldosterone antagonists e.g. spironolactone, eplerenone, amiloride
Complications & prognosis
Depends on the cause

18

lab for primary vs secondary hyperaldosteronism

primary - low RAS, high aldosterone

secondary - low renal perfusion so HIGH renin

19

short synacten test

Do plasma cortisol beofre & 30 mins after giving tetracosactide
(Synacthen 250 μg) IM
Addison’s is excluded if 30minute cortisol is >550nmol/L
( steroid drugs may interfer with this assay)


Synacthen = ACTH

20

hyponatremia symptoms

Na <135
Brain - headache, confusion
Falls, coma,deep somnolence and seizure
Cardioresp distress
N V anorexia

21

hyponatremia screening for cause

- U&E
- Serum & urine osmolality
- Urinary sodium
- glucose (High sugar - pseudohyponatraemia (add approx. 4.3mmol/L to plasma Na + for every 10mmol/l rise in glucose above normal)

22

isotonic hyponatremia

hyperproteinemia
Hyperlipidemia

23

Hypertonic hypoglcyemia

hyperglycaemia
mannitol, orbital, glycerol, maltase
radiocontrast agents

isotonic - serum osmolarity - 280-295 mosm/kg

24

hypotonic hypovolemic hyponatremia

UNa<10
- dehydration
- diarrhea
- vomitting

UNa > 20
(reduced salt loses)
- Diuretics
- ACE inhibitors
- Nephropathesis
- Mineralocorticoids deficiency
- cerebral sodium wasting syndrome

25

hypotonic euvolemic hyponatremia

1. SIADH
2. Post op hyponatremia
3. Hypothyroidism
4. Psychogenic polydipsia
5. Beer potornania
6. Drugs - diuretics, thiazide, ace -
7. Edurance exercise
8. adrenocorticotropin deficiency

26

hypotonic hypervolemia hyponatremia

OEDEMATOUS STATES
- CCF
- liver disease
- Nephrotic syndrome
- Advanced kidney disease

27

correction hyponatremia

hypervolemia or euvolemic - fluid restrict, water intake < 1.5

hypovolemic - give them normal saline or RINGERS

with hyponatraemia with moderate &severe symptoms, 3% saline( usually 150mls

28

How to correct low Na

- Na+ at 0.5mmol / h

Not more than 12 -16 h or 0.5 - 1.0mmol per hour

Correct slowly to prevent osmotic demyelination

29

Hypernatremia vulnerable groups

elderly
confused,
children
unconscious

30

screen for cause HYPERNATREMIA

Serum osmolality ( hyperosmolar in hypernatraemia)

Urine osmolality
Low: often have Diabetes insipidus - see DI lecture
High: unreplaced GI, renal, or insensible losses or osmotic diuresis

Check glucose (to look for uncontrolled diabetes as a cause)

Urinary sodium

31

Serum and urine osmolarity in DI and SIADH

DI
- low urine osmolality (can't concentrate urine - therefore low solutes in urine)
- High serum osmolality

SIADH
- high urine osmolality
- low serum osmolality

32

treatment of hypernatremia

h2O orally
- give IV fluids slowly to prevent cerebral oedema

33

Ecg HYPERKALEMIA

all tented T waves, small p waves,
widened QRS- eventually becoming sinusoidal &
leading to ventricular fibrillation

34

Treatment HyperKalemia - URGENT (K>6)

10ml calcium gluconate IV (
Insulin- dextrose e.g. 5-10 units actrapid in 50mls of 50% Dextrose IV
Nebulised salbutamol 2.5-5mg neb stat
Patients in renal failure with hyperkalaemia - dialysis

35

Non urget Treatment HyperKalemia

find the cause
- Polystrene sulfonate resin (e.g. Calcium reosnium 15 g/ po tds) can be used as it binds K+ in the gut , bringing down K+ levels over a few days.

36

Causes of HYPOKALEMIA

Vomiting/ nasogastric suction
Diarrhoea
Intestinal fistula
Ileostomy
Rectal villous adenoma
Renal tubular failure/ other renal losses
Medications e.g. Diuretic therapy, salbutamol
Cushing’s syndrome/ Conn’s syndrome
Alkalosis
Bowel cleansing pre-colonoscopy preparations/ laxatives
Osmotic diuresis

37

Clinical Hypokalemia

Usually asymptomatic
Muscle weakness
Hypotonia
Hyporeflexia
Cramps
Tetany
Palpitations
Light-headedness (arrhythmia)

38

Complication of hypokalemia

Arrhythmia
paralysis
rhabdomyolysis
diaphragmatic weakness

39

ECG hypokalemia

U wAVE
decreased T waves
ST segment depression
PR interval prolongation
QRS prolongation

40

TREATMENT hypokalemia

MILD-MOD
10-20kcl ORAL given 2-4 times a day

SEVERE
IV 20-40 KCL in 1 L of normal saline over 6-8 hours

41

Max rate of infusion for K+

10-20 mmol/h

42

hypomagnesium cause

Severe diarrhoea
Alcohol misuse
Diuretics
Total parenteral nutrition
Renal tubular acidosis
Malabsorption/ malnutrition
Diabetic ketoacidosis

43

if you correct K too fast what can happen

Cardiac arrest

44

treatment hypomagnesium

Mil - oral Mg
Severe - IV Mg sulfate in a solution of normal saline or dextrose

45

Clinical hypomagnesium


Asymptomatic
Paraesthesia
Ataxia
Seizures
Arrhythmias
Tremor
Tetany

46

treatment of hypercalemia

IV saline administration (watch for fluid overload)
Bisphosphonates (inhibit osteoclasts e.g. IV zolendronic acid
SE: Flu like illness, osteonecrosis of jaw, bone pain, hypocalcaemia)
Calcitonin
Steroids: used in hypercalcaemia associated with sarcoidosis

47

treatment of hypercalcemia

Mild - ORAL vit D and calcium
- if no response on oral switch to UV

Severe- 10ml of 10% calcium glucoronate

Correct Mg if low


48

what type of calcium do you use in CKD

Calcitriol (this is the active form and therefore prevents the kidney from activating it

49

hypoglycaemia definition

low blood surgery when level drops < 3.9 mmol/L
It consistent Whipple's train
- symptoms consistent hypoglycaemia
measurement low plasma glucose
relief of symptoms after plasma glucose

50

Treatment

15-20mg fast acting carb
- dextrose, lucosade(100mls), sweetened fruit juice
- glucotabs - 4g each so 4-5 chewable ones

If severe with coma or confusion
- At home - IM glucagon 1mg
- Inhospital - 50% dextrose 50mls IV
200-300 of 10% dextrose IV

51

2 dynamic function test for evaluating HYPOpituitarism

Growth hormone deficiency testing:
1) Insulin induced hypoglycaemia test- risk of seizures/ angina/ hypoglycaemia/adrenal crisis.
2) Arginine & growth hormone releasing hormone test

ACTH deficiency testing:
1) Short synacthen test to assess adrenal axis
2) Cosyntropin/ rapid ACTH stimulation test 

52

pheochromocytoma 10% rule

10% are malignant
10% are extra- adrenal
10% bilateral
10% familial

MEBF

53

biochemical test for phaeochormocytoma

24hour urinary testing VMA, catecholamines or metenephrines ( most sensitive)
- repeat urinary testing x 3 (episodic)

Plasma catecholamines & metenephrines

54

Images for phaeochormocytoma

MRI ( T2 weighted ) with gadolinium contrast

CT with contrast

Nuclear imaging with radioactive tracer can also be used e.g PET, MIBG scan

55

subclinical hypothryodisim

TSH mildly increase , T3 and T4 normal
ONLY TX
Reasons to treat
1. Risk to become clinical
- previous Graves/ autoimmune
- positive thyroid antibody
- goitre
2. Hyperlipidaemia
3. atherosclerosis
4. Pregnancy or trying
5. Reduce quality of life if symptomatic
6. TSH >10

56

acute thyroiditis

HIGH ESR
TENDER THYROID

57

Most common cause of hypothyroidism and how to distinguish

Hashimotos thyroidisim
- HIGH ANTIBODIES TITERS
anti-thyroids peroxidase antibodies (anti TPO)
anti-thyroidgnobulin antibodies

58

treatment hypothyroidism

Start 50-100 mcg per day
increase 25-50mcg in increments by 4-6 weeks until TSH stable

ONCE stable monitor in 6-12 months

59

treatment of hypothyroidism in elderly and ischemic heart disease

Caution in
Start at 25micrograms daily & adjust slowly in 4 weekly increments of 25 micrograms ( risk of precipitating angina or myocardial infarction)

60

Drug that interfere with absorption
with thyroxine absorption

AFFECTS ABSORPTION
Antacids (aluminum containing)
Iron tables
Calcium tablets

INCREASES METABLOSIM
- anti-epileptic
- Rifampin

61

complication of hypothyroidism

Myxoedema coma
Ischaemic heart disease
Weight gain/ obesity
Rare neurologic problems include reversible cerebellar ataxia, dementia, psychosis, and myxedema coma.
Hashimoto's encephalopathy

62

important additional test to get any female elderly with hypothyroidism

- DEXA

63

risk factors and pathogenesis for thyroid eye disease and findings

SMOKING
- exopthalmous
- ptosis
- conjunctival edema
- ophthalmoplegia
- papillodema
- loss of colour vision

RETRO - orbital inflammation and lymphocyte inflammation results in swelling of orbit

64

Jod Basedow presentation

hyperthyroidism following administration of iodine

65

causes of hyperthyroidism

Graves’ disease ( 60-80% of cases)
Toxic multi-nodular goitre
Solitary toxic thyroid nodule
Thyroiditis (Hashimoto’s; deQuervains)
Post-partum thyroiditis
Ectopic thyroid tissue eg. metastatic follicular thyroid cancer, struma ovarii
Medications eg amiodarone, l-thyroxine excess
Jod-Basedow phenomenon

66

pretibial myexedema and exophthalmus in hyperthryoidism

DUE to TSH receptor - fibroblast behind the eye and skin have TSH receptors therefore glycoamminoglycans "DOUGH like apperenace"

67

antibody in hyperthyroidism

TSH receptor antibodies (graves)
antithyroid peroxidase (autoimmune)

68

Treatment of Graves

1. Beta blockers - symptoms
2. Carbimazole or Propylthiouracil (PTU)

3. Radio-iodine

4. Surgery
- obstructive goitre
- contraindication to RAI

69

what precaution do u have to tell patients who start Carbimazole

STOP medication if they get a sore throat or mouth ulcers
- b.c can can agranulocytosis

70

treatment for thyroiditis

Analgesia- NSAIDS
Beta-blockers
Steroids (taper over 2 weeks)
L- thyroxine --> if become hypothyroid
Monitor TFT’s closely- every 2-4 weeks until normalise

71

reason to treat subclinical hyperthyroidism

Atrial fibrillation
Osteoporosis
Increased cardiovascular disease risk
Progression to clinical hyperthyroidism
Multi nodular Goitre

72

complications of hyperthyroidism

Atrial fibrillation
Heart failure
Angina
Osteoporosis
Ophthlamopathy
Oligomenorrhoea/ amenorrhoea
Gynaecomastia

73

success rate of RAI

10-205 FAIL frist time and require a 2nd dose

74

Dx of T1DM

Fasting Plasma Glucose > 7.0 mmol/l ⃰ Fasting is defined as no caloric intake for at least 8 hours
Plasma glucose > 11.1 mmol/l two hours following Oral Glucose Tolerance Test. (OGTT) ⃰
Random plasma glucose >11.1 mmol/l ( in symptomatic patient)
HBA1C > 48 mmol/mol. ( >6.5%) ⃰

75

antibodies in islet cell

AntiGAD
isle cell antibody

76

blood target levels for t1DM

FBG: 5-7 mmol/litre
PG: 4-7 mmol/litre before meals
PG: 5-9 mmol/litre at least 90 minutes after eating

HbA1C: <6.5%

77

patient suffering from depression constipation and a pain in his back

think hypercalemia
- measure serum Calcium levels

78

22 year old complains of dizziness and feeling light headed when she stands up to go to the toilet , she noticed her scar is much darker

THINK ADDISONS disease
- SYNACTHEN TEST
you inject synacthen (ACTH) and you would expect their to be an increase cortisol