Endocrinology Flashcards
1
Q
What are the causes of hypoparathyroidism?
A
Di George Syndrome
Malignancy
Autoimmune destruction of parafollicular cells
2
Q
How does hypoparathyroidism present?
A
Cramp & tetany of muscles
Pins & needles
3
Q
What is Chvostek’s sign?
A
Twitching of facial muscle when tapping nerve
4
Q
What is trousseaus signs?
A
Inflamm of BP cuff over sys BP for a period of time –> tetany of hand muscles
5
Q
What are the blood cell changes in hypoparathyroidism?
A
Decreased PTH
Decreased calcium
Increased phosphate
6
Q
How is hypoparathyroidism managed?
A
Calcium & vitamin D supplements
7
Q
Describe the pathophysiology of pseudohypoparathyroidism?
A
Caused by genetic receptor abnormality –> PTH resistance –> PTH receptor cannot be stimulate –> increased serum PTH levels –> hypocalcaemia –> even more PTH
8
Q
What are the complications of pseudohypoparathyroidism?
A
Subcut calcification Mental retardation Brachydactyly Obesity Bone abnormalities
9
Q
What is the DEXA score for osteopenia?
A
1-2.5
10
Q
What is the DEXA score for osteoporosis?
A
> 2.5
11
Q
Disease: low calcium, low phosphate, high ALP, high PTH
A
Osteomalacia
12
Q
Disease: high calcium, low phosphate, high ALP, high PTH
A
Primary hyperparathyroid
13
Q
Disease: low calcium, high phosphate, high ALP, high PTH
A
CKD
14
Q
Disease: normal calcium, normal phosphate, normal PTH, high ALP
A
Pagets
15
Q
What effect does PTH have on the bone?
A
Increases resorption resulting in increased serum calcium
16
Q
What do osteoclasts do?
A
Bone resorption
17
Q
What do osteoblasts do?
A
Bone formation
18
Q
Which bone is the porous type?
A
Trabecular
19
Q
Which bone is the dense type?
A
Cortical
20
Q
What effect does PTH have on the kidney?
A
Causes Vit D activation
Tubular reabsorption resulting in increased calcium and less phosphate
21
Q
When is calcitonin secreted?
A
In extreme hypercalcaemia
22
Q
What is primary hyperparathyroidism caused by?
A
Overactivity of the gland
23
Q
What is secondary hyperparathyroidism?
A
Physiological response to low calcium
24
Q
What is tertiary hyperparathyroidism?
A
Autonomous gland after chronic secondary
25
What are the features of hyperparathyroidism?
Stones, bones, moans and abdominal groans
26
How is hyperparathyroidism diagnosed?
Increased calcium
Increased PTH
Increased urinary calcium
27
What are the features of hypercalcaemia?
Muscle weakness, constipation, stones, moans
28
What is the management of hyperparathyroidism?
Adenoma excision
Avoid lots of calcium and vitamin D
High fluid diet
29
What is pheochromocytoma?
Tumour of the sympathetic paraganglia cells
30
What syndrome in pheochromocytoma assoc with?
MEN 2
31
What is the classic triad of pheochromocytoma?
Hypertension, sweating, headaches
32
What are the features of phaechromocytoma?
Hypertension, arrhythmia, sweating, pallor, headaches, anxiety
33
How is phaechromocytoma investigated?
Urinary catecholamines, CT/MRI, MIBG
34
How is phaeochromocytoma managed?
Atenolol, phenoxybenzamine, chemotherapy
35
What is Addison's?
Glucocorticoid insufficiency
36
When should Addison's be considered?
Worsening symptoms on thyroxine, Unexplained hypos in T1DM
37
What is the presentation of addisons?
Fatigue and weakness, anorexia, N&V, bronze skin, salt cravings, hypotension, loss of pubes
38
How is Addison's managed?
Hydrocortisone
39
How is Addison's investigated (including findings)?
Low sodium, low potassium, short synacthen test: no cortisol spike
40
What are the two types of cushings syndrome?
ACTH dependent and independent
41
What causes ACTH dependent cushings?
Adenoma in pituitary
42
What causes ACTH independent cushings?
Adrenal adenoma, nodular hyperplasia
43
How does Cushing's present?
Moon face, striae, easy bruising, muscle wasting, central obesity, dysthymia, bone pain
44
How is Cushing's investigated?
Low dose dex test,
High dose dex suppression,
Measure ACTH, DEXA scan
45
What happens to low dose dexamethasone test in Cushing's?
> 50nmol
46
What is the HDDS for in Cushing's?
To determine if pituitary (50%)
47
What are the ACTH levels in Cushing's (dependent on source)?
< 300 in pituitary
< 1 adrenal
> 300 ectopic
48
How is Cushing's managed?
Metyrapone, ketoconazole, surgery (trans-sphenoidal, bilateral adrenalectomy
49
What is the management of bilateral adrenal hyperplasia?
Eplerenone
50
What is Conn's syndrome?
Adrenal adenoma (tumour in zona glomerulosa --> excess aldosterone)
51
What are the features of Conn's?
Hypertension, hypernatraemia, hypokalaemia
52
How is Conn's investigated?
Aldesterone:renin saline suppression
| Usually incidental finding
53
What does the zona glomerulosa produce?
Aldosterone
54
What does aldosterone do?
```
Sodium retention (hence water swell)
Increases BP
```
55
What does the zona fasciculata produce?
Cortisol
56
What controls the zona fasciculata?
ACTH
57
What controls the zona glomerulosa?
RAAS
58
What does the zona reticularis?
DHEA
59
What controls the zona reticularis?
ACTH
60
What does the medulla of adrenals produce?
Adrenaline + noradrenaline
61
What are the adrenalines derived from and where?
Tyrosine in chromaffin cells
62
What is the medulla of the adrenals controlled by?
Sympathetic stimulation
63
State the layers of the adrenal (from superficial to deep)
Connective tissue, z. glomerulosa, z. fasciculata, z. reticularis, medulla
64
What is the thyroid attached to?
Thyroid cartilage and upper end of trachea
65
What do follicular cells produce?
Thyroglobulin
66
What do parafollicular cells produce?
Calcitonin
67
What is T3 made up of?
2 x MIT
68
What is T4 made up of?
MIT + DIT
69
Which thyroid hormone is more biologically active?
T3
70
Where is T4 converted and what to?
T3 in the liver and kidneys
71
High TSH + low T4?
Primary hypothyroidism
72
Low TSH + low T4?
Secondary hypothyroidism
73
Low TSH + high T4?
Thyrotoxicosis
74
High TSH + normal T4?
Subclinical hypothyroidism
75
What is the most common cause of hypothyroidism?
Hashimoto's thyroiditis
76
What are the features of Hashimoto's thyroiditis?
Hypothyroidism: weight gain, constipation, leathery, cold intolerance etc
Firm non-tender goitre
77
How is Hashimoto's thyroiditis investigated?
High TSH, low T3 & T4, Anti-TPO antibodies
78
How is Hashimoto's thyroiditis managed?
Thyroid replacement - levothyroxine
79
What is De Quervains thyroiditis?
Follows viral infection and presents with hyperthyroid
80
What are the phases of De Quervains thyroiditis?
Hyperthyroid, raised ESR, painful goitre (3-6 weeks), euthyroid (1-3 weeks), hypothyroid (weeks - months), return back to normal
81
How is De Quervains thyroiditis investigated?
Iodine uptake scan - globally decreased
82
How is De Quervains thyroiditis managed?
Self limiting, NSAIDs for pain, severe: steroids
83
What is toxic multi nodular goitre?
Autonomous nodules in thyroid which produce T3 & T4
84
What are the features of toxic multi nodular goitre?
Everything in overdrive (hyperthyroid),
Asymmetrical nodular goitre,
Tremor,
Moist, smooth skin
85
How is toxic multi nodular goitre investigated?
iodine uptake scan - patchy uptake,
Low TSH, high T3 &T4,
USS
86
How is toxic multi nodular goitre managed?
Radioiodine therapy
| Surgery
87
What is the most common cause of thyrotoxicosis?
Graves
88
What are the features of Graves?
Goitre,
Exopthalmus,
Pretibial myxoedema,
Hyperthyroidism; weight loss, heat intolerance, anxiety, diarrhoea, palpitations, tachycardia
89
How is graves investigated?
Low TSH, high T3 & T4,
| Anti-TSH
90
What is the management of Graves?
Carbimazole, PTU,
Surgery,
Radioiodine therapy
91
What is an important complication of carbimazole?
Agranulocytosis
92
What is the HbA1c target?
7% or below - 48mmol
93
What are the side effects of metformin?
Vomiting & diarrhoea, rash, lactic acidosis
94
How much does metformin reduce the HbA1c by?
15-20mmol
95
What effect does metformin have on weight?
neutral
96
What is the basic mode of action of metformin?
Increased insulin sensitivity
97
What is the basic mode of action of sulphonylureas?
Increases pancreatic release - must produce at least some
98
Does sulphonylureas have any effect on T2DM complications?
Microvascular prevention
99
What are the side effects of sulphonylureas?
Hypos, weight gain
100
When should sulphonylureas be avoided?
In severe hepatic and renal failure
101
What effect do TZDs have on T2DM complications?
Macrovascular prevention
102
What are the side effects of TZDs?
Hypos, weight gain, doubles risk of heart failure
103
What is the management of mild hypoglycaemia?
Glucose tabs
104
What is the management of moderate hypoglycaemia?
dextrogel
105
What is the management of severe hypoglycaemia?
IV glucose 10%
106
What random blood glucose measurement may indicate diabetes?
> 11.0
107
What fasting BG is normal?
< 5.6
108
What fasting BG indicates pre diabetes (impaired fasting glucose)?
5.6 - 6.9
109
What fasting BG indicates diabetes?
> 6.9
110
What oral glucose tolerance test result is normal?
< 7.8
111
What oral glucose tolerance test result indicates impaired glucose tolerance?
7.8 - 11
112
What oral glucose tolerance test result indicates diabetes?
> 11.0
113
What is the most common thyroid cancer?
Papillary
114
What is medullary thyroid cancer?
Cancer of parafollicular cells - secretes calcitonin
115
Which thyroid cancer carries the worst prognosis?
Anaplastic
116
What is the histology of papillary thyroid cancer?
papillary projections and pale empty nuclei
117
Does papillary cancer metastasise commonly?
Lymph nodes yes
118
How do follicular adenomas usually present?
Solitary thyroid nodule
119
How is follicular carcinoma and adenoma differentiated?
microscopically capsular invasion is seen in carcinoma
120
Does follicular carcinoma metastasise?
Yes, vascular invasion predominantly
121
Who gets anaplastic thyroid cancer?
Old ladies
122
What is ineffective against thyroid cancer?
Chemotherapy
123
What is part of MEN 1?
Pituitary adenoma, parathyroid hyperplasia, pancreatic cancer
124
What is part of MEN 2a?
Parathyroid hyperplasia, medullary thyroid cancer, phaeochromocytoma
125
What is part of MEN 2b?
Neuromas, Marfanoid features, Medullary thyroid cancer, phaechromocytoma
126
What does the anterior pituitary produce?
Gonadotrophins, GH, PRL, TSH, ACTH
127
What does the posterior pituitary produce?
Oxytocin & ADH
128
What is the initial management of hypercalcaemia?
Saline
129
What is the medical management of pheochromocytoma?
Alpha blocker > beta blocker
130
What is the most common cause of Addison's?
Autoimmune adrenalitis
131
What is the HbA1c in pre diabetes?
42-47
132
What are the features of Klinefelters?
Tall, infertility, small testes, gynaecomastia, no secondary sexual characteristics
133
What drugs can cause a raised PRL?
Metoclopramide, domperidone
134
What is used to monitor response to treatment in hypothyroid?
TSH
135
What test is used to differentiate between T1 and T2 DM?
C-peptide
136
When should another drug be added in diabetes?
HbA1c > 58 (7.5%)
137
What are the features of HHS?
Increased serum osmolality, no ketosis, hyperglycaemia
138
What are causes of HHS?
Illness, dehydration
139
What is the first line management of a prolactinoma?
Bromocriptine, cabergoline
140
Bone thing steroids increase risk of
Osteonecrosis, osteoporosis
141
What is the BP target in T2DM if there is no organ damage?
140/80
142
What is the Bp target in T2DM if there is organ damage?
130/80
143
What is the management of DKA?
Fluid resus, insulin infusion, potassium replacement
144
What is the management of HHS?
Fluid resus, allow time before insulin
145
What happens to steroid doses in Addisons if they get ill?
2 x hydrocortisone, normal fludrocortisone
146
What HbA1c is diagnostic of diabetes?
> 6.5%
147
What does the ABG/electrolytes show in Cushing's?
Hypokalaemia metabolic alkalosis
148
What is an easily modifiable risk factor for thyroid eye disease?
Smoking
149
What do SGLT2s increase your risk of?
Thrush, urine infections
150
What is the optimal treatment in HNF1A-MODY?
Sulphonylureas
151
What are the levels in sick euthyroid?
TSH -/raised, low T3 & T4
152
What is the treatment for post menopausal women with a fracture (endocrinologically)?
Bisphosphonates
