Endocrinology Flashcards
(137 cards)
1
Q
ADH is released by the?
A
Posterior pituitary
2
Q
Pituitary adenoma causes what visual defect?
A
Upper bi-temporal quadrantanopia
3
Q
What is PITS qaundrantonopia?
A
Parietal inferior
Temporal superior
4
Q
Microadenoma?
A
<10
12 monthly MRI then 3 yearly
5
Q
Macroadenoma?
A
10+
6 monthly MRI and yearly bloods
6
Q
Investigations for pituitary adenoma?
A
MRI pituitary
Pituitary profile
Visual field testing
7
Q
Treatment of prolactinoma?
A
Cabergoline
Bromocriptine
Surgery transphenoidal if medical management fails
8
Q
What is cabergoline?
A
Dopamine receptor agonist to reduce tumour size
9
Q
When do you use bromocriptine?
A
In pregnancy/ wanting to conceive in pituitary adenoma
10
Q
What is Cushings disease?
A
Pituitary adenoma secreting ACTH -> cortisol
11
Q
What are the screening tests for Cushings disease?
A
X2
24h urinary cortisol
Midnight salivary cortisol tests
Midnight overnight/ low dose dexamethasone suppression test
12
Q
How do you diagnose Cushings disease?
A
Low dose dexamethasone suppression test- cortisol high
High dose dexamethasone test- suppresses
13
Q
Treatment of Cushings disease?
A
Trans-sphenoidal resection
Replace corticosteroids
14
Q
How do you treat Cushings disease if surgery is contraindicated?
A
Metyrapone
15
Q
What is pseudo-cushings syndrome?
A
Features secondary to alcohol excess
16
Q
What is acromegaly?
A
Pituitary adenoma secreting GH
17
Q
Screening of acromegaly?
A
IGF-1
18
Q
Diagnosis of acromegaly?
A
OGTT
19
Q
Investigations of acromegaly?
A
Prolactin, IGF-1, OGTT, HbA1c, CT/MRI pituitary
20
Q
Treatment of acromegaly?
A
Transphenoidal surgery +/- radiotherapy
21
Q
How do you treat acromegaly if surgery fails?
A
Octreotide
Pegvisomant (GH antagonists)
Bromocriptine
22
Q
Follow up to detect acromegaly recurrence?
A
IGF-1, GH, prolactin
23
Q
Increased risk of what in acromegaly?
A
bowel malignancy (colonoscopy)
HF (ECHO)
24
Q
What is SIADH?
A
Excess ADH causing euvolaemic hyponatraemia
25
What does ADH do?
up-regulates aquaporin-2 channels to CD's allowing concentration of urine, increasing BP
26
Causes of SIADH?
Pituitary adenoma
SCLC
Pulmonary disease
SSRIs, tricyclics, carbamazepine
meningitis
27
Investigations of SIADH?
Euvolaemic hyponatraemia with high urinary sodium >20
28
Management of SIADH?
Fluid restriction 750ml
if in effective Domeclocylcine or vaptans
29
What is arginine vasopressin disorder?
Diabetes insipidus, deficiency of ADH production
30
Forms of diabetes insipidus?
Craniogenic (deficiency)
Nephrogenic (resistance)
31
How is diabetes insipidus seen?
thirst and excessive urination
32
Causes of craniogenic DI?
Inherited (AD neurohypohyseal)
Hypopituitarism- trauma, stroke, meningitis
33
What are causes of nephrogenic DI?
Wolframs syndrome
Lithium
Domoclocycline
Electrolyte disturbances
34
Investigation signs of diabetes insipidus?
Urine osmolality LOW <300
Serum osmolality HIGH >300
HyperNa
35
Diagnostic test for DI?
Fluid deprivation test
+
Desmopressin
36
What is fluid deprivation test?
Increases serum osmolality but wont increase urine osmolality (will not concentrate)
37
Why then give desmopressin after fluid deprivation test in DI?
Craniogenic will concentrate urine (increase urine osmolality)
Nephrogenic urine osmolality still low
38
Treatment of craniogenic DI?
Desmopressin
39
Treatment of nephrogenic DI?
Treat underlying cause: electrolytes, drugs
40
What is Cushings syndrome?
High cortisol from:
- Cushings disease
- Ectopic ATCH lung/thymic carcinomas
- Adrenal adenoma/
Adrenal carcinomas
41
Diagnosis of cushing syndrome?
Low dose dexamethasone suppression test- doesnt suppress
High dose dexamethasone test- doesnt suppress
ACTH low in adrenal adenoma, high in ectopic/pituitary
42
Further investigation of cushing syndrome?
MRI pituitary
CT TAP
Inferior petrosal sinus sampling
43
Screening for cushing syndrome?
24h urinary free cortisol
44
Management of cushing syndrome?
Metyrapone
Ketoconazole
+ steroids
45
Adrenal gland is divided into the?
Glomerulusa
Fasciculate
Reticularis
Medulla
46
Glomeruluosa produces?
Aldosterone
47
Fasciculata produces?
Cortisol
48
Reticularis produces?
Androgens
49
Medulla produces?
Adrenaline and noradrenaline
50
What is waterhouse-friedrichsen syndrome?
Haemorrhage and destruction of adrenals
51
Why can primary adrenal insufficiency occur?
Addison's disease (autoimmune)
Surgical removal
Trauma
TB
Waterhouse-friedrichson
52
What are causes of secondary adrenal insufficiency?
Base of skull fracture
neoplasms
Sheehan syndrome
53
What causes tertiary adrenal insuffiency?
Long term steroids suppressing CRH from hypothalamus
54
Signs of adrenal insufficiency?
Hypotension
HypoNa
Hypoglycaemia
Hyperkalaemia
Increased skin pigmentation
NAGMA
55
Investigations for addisons?
Morning cortisol (or random)
ACTH
Renin/ aldosterone
Adrenal cortex antibodies
21-hydroxylase antibodies
56
ATCH in primary and secondary adrenal insufficiency?
ACTH high in primary
ACTH low/normal in secondary
57
Diagnosis of adrenal insufficiency?
Short synacthen test
58
What is the short synacthen test?
Check blood cortisol then give synthetic ACTH, recheck cortisol after 30 mins, then 60 mins, in healthy should double
59
What is Conns syndrome?
Adrenal adenoma causing primary hypoaldosteronism (too much aldoesterone)
60
What is primary hyperaldosteronism?
Adrenal producing too much aldosterone due to:
- Adrenal hyperplasia
- Conn's syndrome (adrenal adenoma)
- Functioning carcinoma
61
What is secondary hyperaldoesteronism?
Too much renin due to:
- Renal artery stenosis
- Renin secreting tumours
- hypovolaemia
62
How is hyperaldosteronism seen?
Treatment resistant hypertension
Hypokalaemia
63
What is hyperaldoesteronism linked to?
Osteoporosis
64
What does aldosterone do?
Increases Na reabsorption at DCT
Increases K+ secretion at DCT
Increases H+ secretion at collecting ducts
65
Screening for hyperaldosteronism?
Aldosterone: Renin ratio when off anti HTN
then
Liqourice excess
66
Diagnosis of hyperaldoesteronism?
Selective adrenal vein sampling
PET/ CT adrenals
67
Management of hyperaldoesteronism?
Surgical removal if unilateral
Bilateral- spironolactone/ eplerenone/ amiloride
68
What does amiloride do?
K sparing diuretic
69
What is the RAAS system?
Renin angiotensin aldosterone system
70
What secretes renin?
Juxtaglomerular cells in the afferent arterioles of the kidney due to low BP
71
What does renin do?
Coverts angiotensinogen (from the liver) to angiotensin 1
72
What does angiotensin 1 go on to?
Converted by ACE (from lungs) to angiotensin 2
73
What does angiotensin 2 do?
Stimulates aldosterone to be secreted by the adrenals (zona glomerulosa)
74
What is subclinical hyperthyroidism?
Normal T3/T4
Depressed TSH
75
Monitoring/ treatment for subclinical hyperthyroidism?
TFTs 6 monthly
No treatment
76
Causes of exogenous hyperthyroidism?
Strum ovarii- teratroma in ovaries
HCG excess in molar pregnancy
77
What is Graves disease?
Anti TSH receptor antibodies
78
What are TSH receptors on the thyroid gland?
GPCR signalling cAMP
79
What is graves linked to?
HLA D3
HLA DR 4
80
Goitre in graves disease?
Diffuse non tender goitre
Diffuse uptake on scans
81
Signs of graves disease?
Clubbing
Pretibial myxoedema
Exophthalmos
Corneal ulcers
Optic atrophy with colour vision loss
Lid retraction
Hyperreflexia
82
Risk of graves in pregnancy?
IgG crosses placenta causing neonatal graves disease
83
Drug causes of hyperthyroidism?
Post amiodarone
Contrast
84
Management of hyperthyroidism?
1- Titration
Carbimazole or propylthiouracil for 1-2 years then down titrate
85
What does carbimazole and propythiorucil do?
Block thyroid peroxidase, preventing iodination and coupling in the hormone synthesis pathway
86
Who cant take carbimazole?
Pregnant women as associated with aplasia cutis
87
Important SE of carbimazole?
Agranulocytosis
88
What can you give to pregnant women with hyperthyroidism?
Propylthiouracil in first trimester
Methimazole in 2-3rd trimester
89
Second line in treatment for hyperthyroidism?
2- Block and replace
High dose carbimazole/ propylthiouracil
+
Levothyroxine (T4)
90
Third line treatment of hyperthyroidism?
Medical ablation with radio-iodine (131)
91
Who cant have radio-iodine?
Pregnant women
Breast feeding
92
How long not to conceive after radio-iodine?
Women 6 months
Men 4 months
93
How long to avoid young children and elderly with radio-iodine?
2 weeks
94
Issue with radio iodine?
Can worsen graves opthalmopathy in first 3 months
95
Who gets radio iodine?
Toxic adenoma
MNG
96
If medical management unsuccessful or goitre causing compression do?
Surgical ablation and thyroidectomy
97
Complications of thyroidectomy?
Parathyroid removal accidentally
HypoCa
Haemorrhage
Recurrent laryngeal nerve damage
98
Thyrotoxic crisis precipitants?
Surgery
radioiodine
Gastric losses
Intercurrent illness
99
Symptoms of thyrotoxic storm?
Hyperpyrexia
Sweating
D+V
Severe hypertension
AF
Psychosis
100
Management of thyrotoxic storm?
Propylthiouracil
Prednisolone (reduces T4-T3 conversion)
Propranolol
Active cooling
101
What is amiodarone induced thyrotoxicosis?
Hyperthyroidism/hypothyroidism secondary to amiodarone as it contains iodine as it has a long half life
102
What is type 1 AIT?
In pre-existing hyperthyroidism iodine increases hormone production via Jod-basedow phenomenon
103
Uptake scan in T1 AIT?
Increased uptake
104
IL-6 in AIT T1?
Normal
105
What is Type 2 AIT?
Patients without pre-exisiting disease, amiodarone causes toxic effect
106
Uptake scan and IL-6 in T2 AIT?
Reduced uptake
IL-6 raised
107
Treatment of T2 AIT?
Steroids
108
Treatment of T1 AIT?
Carbimazole
109
When can AIT cause hypothyroidism?
Most common via Wolff-Chiakoff effect
110
What is subclinical hypothyroidism?
Normal T3/T4
Raised TSH
111
What is sick euthyroid syndrome?
When unwell low T3/4 and normal TSH
Repeat 3 months after recovery
Levo if symptomatic, TSH >10, high risk CV disease or autoimmunity
112
Causes of hypothyroidism?
Iodine deficiency
Hashimoto thyroiditis
De Quervains thyroiditis
Damage
113
Drugs that may cause hypothyroidism?
Amiodarone
Iodine
Lithium
114
What is Hashimoto's thyroiditis?
Autoimmune hypothyroidism with a painless firm goitre
115
What are the antibodies in hashimotos?
Anti TPO
Anti thyroglobulin
Anti TSH receptor (blocking)
116
What is De Quervain's thyroiditis?
Subacute granulomatous thyroiditis
Painful goitre due to infection
117
Infections common in De Quervains thyoiditis?
Viral URTI
Cocksakie
Mummps
Measles
Adenovirus
118
Treatment of De Quervains thyroiditis?
NSAID and supportive, self limiting
119
What is subacute lymphocytic thyroiditis?
Silent and painless hypothyroidism 6 months post partum
120
Why start levothyroxine slowly?
Long half life and increased risk of MI
121
What to check before starting levothyroxine?
Cortisol as can predicate addisonian crisis
122
When to recheck TFTs?
4-6 weeks
123
Psammoma bodies, Orphan-Annie ground glass nuclei
Papillary adenocarcinoma of thyroid
124
Tumour marker for papillary adenocarcinoma of the thyroid?
Thyroglobulin
125
Management of papillary adenocarcinoma of thyroid?
>1cm = thyroidectomy
<1cm = hemithyroidectomy + LN dissection
+/- radio-iodine
Thyroxine to suppress TSH to <0.1
126
Hurthle cell change, younger patient?
Follicular adenocarcinoma
127
Follicular adenocarcinoma tumour marker/
Thyroglobulin
128
Worst prognosis for thyroid cancer?
Anaplastic carcinoma (older patients)
129
Anaplastic thyroid cancer tumour marker?
None
130
Giant osteoclastic liek cells with sarcomatous spindles?
Anaplastic carcinoma
131
Management of anaplastic thyroid cancer?
Usually inoperable and causes local compression palliative tracheostomy/ radiotherapy
132
Medullary carcinoma is?
Endocrine tumour of C-cells parafollicular cells
133
Tumour marker for medullary carcinoma?
Calcitonin
CEA
134
Management of medullary carcinoma?
Total thyroidectomy + LN dissection
Rule out phaeo as MEN2
135
Tumour marker follow up for medullary carcinoma?
calcitonin
136
Management of follicular adenoma?
Benign but cant tell apart for hemithyroidectomy
137
