Endocrinology Flashcards
(211 cards)
1
Q
Where does the thyroid attach to?
A
Thyroid cartilage
Cricoid cartilage
Trachea
2
Q
What does the hypothalamus secrete with regard to the thyroid?
A
Thryotropin releasing hormone (TRH)
3
Q
What does the pituitary secrete with regard to thyroid?
A
TSH
4
Q
What hormones does the thyroid produce?
A
T3 and T4
5
Q
Which thyroid hormone is more abundant?
A
T4 (90%)
6
Q
Which thyroid hormone is more potent?
A
T3 (4x)
7
Q
What is thyroid hormone needed for?
A
BMR, thermogenesis, metabolism, growth, normal CNS function
8
Q
When are thyroid hormones at their highest?
A
At night
9
Q
What is hypothyroidism?
A
Clinical effects of having a lack of thyroid hormone
10
Q
What are symptoms of hypothyroidism?
A
Tiredness, lower mood, cold intolerance, weight gain, constipation, hoarseness, dry skin, decreased memory, myalgia, cramps
11
Q
What are some signs of hypothyroidism?
A
Bradycardia, ataxia, cold hands, yawning, oedema, round puffy face
12
Q
What is the difference between primary and secondary hypothyroidism?
A
Primary is a problem with the thyroid gland
Secondary is due to a problem in pituitary or hypothalamus
13
Q
What are causes of primary hypothyroidism?
A
Hashimotos thyroiditis, iodine deficiency, past thyroidectomy, drug induced (amiodarone, lithium)
14
Q
What are causes of secondary hypothyroidism?
A
Congenital, craniopharyngioma, panhypopituitarism,
15
Q
What do TFTs show in primary hypothyroidism?
A
High TSH, Low T4
16
Q
What is the management of hypothyroidism?
A
Thyroxine replacement - start at 50mcg and adjust every 4 weeks until optimised
17
Q
When should you check TFTs after a dose change?
A
8-12 weeks
18
Q
How many thyroxine need adjusted in pregnancy?
A
Dose increase by 25-50mcg
19
Q
What are side effects of thyroxine?
A
Hyperthyroidism, worsening of angina, AF
20
Q
What is hyperthyroidism?
A
Clinical effects of excess thyroid hormone
21
Q
What are symptoms of hyperthyroidism?
A
Diarrhoea, weight loss, appetite increase, sweating, heat intolerance, palpitations, tremor, irritability, labile emotions
22
Q
What are the signs of hyperthyroidism?
A
Fast/irregular pulse, warm moist skin, fine tremor, palmar erythema, lid lag, goitre, nodules, bruit
23
Q
What are the specific signs of Graves disease?
A
Exophthalmos, pretibial myxoedema, thyroid acropachy
24
Q
What are the main causes of hyperthyroidism?
A
Graves disease, toxic multinodular goitre, toxic adenoma, ectopic thyroid tissue, subacute thyroiditis, post partum thyroiditis, drugs (amiodarone/lithium)
25
What do TFTs show in hyperthyroidism?
Low TSH and high free T4
26
What is the management of hyperthyroidism?
Carbimazole
27
What is the major risk of carbimazole?
Agranulocytosis
28
What drug is given for hyperthyroidism during pregnancy?
Propythiouracil
29
What do TFTs show in sick euthyroid syndrome?
Low TSH and low T4
30
What do TFTs show in subclinical hypothyroidism?
High TSH normal T4
31
What do TFTs show in poor thyroid medication compliance?
High TSH normal T4
32
What surgical options are there for hyperthyroidism?
Thyroidectomy or radioiodine ablation
33
What is thyroid cancer strongly associated with?
Radiation
34
How does thyroid cancer present?
Palpable nodules. Often no signs of hypo/hyperthyroidism as does not secrete hormones
35
What is the commonest type of thyroid cancer?
Papillary
36
What is the 2nd commonest type of thyroid cancer?
Follicular
37
What is medullary thyroid cancer associated with?
MEN2
38
What does medullary thyroid cancer secrete?
Calcitonin
39
What thyroid cancer carries the worst prognosis?
Anaplastic
40
How is thyroid cancer treated?
Mainly surgical
41
What hormone regulates calcium homeostasis?
PTH
42
How does PTH work?
Stimulates osteoclast activity to get calcium released from the bones and increase calcium levels in the blood
43
What hormone does the opposite of PTH?
Calcitonin
44
What are symptoms of hypercalcaemia?
Hypertension, ulcers, fractures, abdominal pain, myopathy, polyuria, thirst/dehydration, confusion, renal stones
45
What are causes of hypercalcaemia?
```
Primary hyperparathyroidism
Malignancy
Drugs (vitamin D, thiazides)
Granulomatous disease - sarcoid, TB
Pagets disease
Being bedridden
```
46
Who does primary hyperparathyroidism commonly affect?
Elderly females
47
What is primary hyperparathyroidism associated with?
MEN1
48
What do bloods show in primary hyperparathyroidism?
Increased calcium, decreased phosphate, increased PTH
49
What are the main causes of primary hyperparathyroidism?
Adenoma, hyperplasia, cancer
50
What is the treatment of primary hyperparathyroidism?
Total parathyroidectomy, conservative management if unsuitable for surgery (Cinacalet)
51
Why does secondary hyperparathyroidism occur?
Because of a low calcium
52
What are causes of secondary hyperparathyroidism?
Low dietary calcium, low vitamin D, chronic renal failure
53
What do bloods show in secondary hyperparathyroidism?
Low calcium, high phosphate, high PTH
54
What treatment do you use for secondary hyperparathyroidism?
Correct the causes
| Phosphate binders, calcium & vitamin D
55
When does tertiary hyperparathyroidism occur?
After prolonged secondary hyperparathyroidism
56
What do bloods show in tertiary hyperparathyroidism show?
Increased calcium, increased phosphate, increased PTH
57
What are symptoms of hypocalcaemia?
Weakness, seizures, bronchospasm, QT prolongation, muscle cramps, paraesthesia, Trousseau sign, fatigue
58
What are causes of hypocalcaemia?
Hypoparathyroidism, vitamin D deficiency, chronic renal failure, pancreatitis, hyperventilation, bone mets
59
What do bloods show in primary hypoparathyroidism?
Low calcium, high phosphate, low PTH
60
What are causes of hypoparathyroidism?
Removal of parathyroids, DiGeorge syndrome, autoimmune, haemochromatosis
61
What is pseudohypoparathyroidism?
Failure of target cells to respond to PTH
62
What features do people with pseudohypoparathyroidism have?
Round faces, obesity, bracydactyly, low IQ
63
What do bloods show in people with pseudohypoparathyroidism?
Low calcium, high phosphate, normal/high PTH
64
What is pseudopseudohypoparathyrodism?
Same as pseudohypoparathyroidism but with normal biochemistry
65
How is hypoparathyroidism treated?
Calcium supplements and calcitriol
66
What is Pagets disease?
Abnormality of bone remodelling resulting in thick but weak bone
67
What do bloods show in Pagets?
An isolated rise in ALP
68
How is Pagets treated?
Bisphosphonates
69
Where are the adrenal glands found?
Bilaterally superior and medial to the upper poles of the kidneys
70
What are the adrenal glands composed of?
Outer cortex and inner medulla
71
What does the zona granulosa of the adrenal cortex secrete?
Mineralocorticoids
72
What does the zona fasciculata of the adrenal cortex secrete?
Glucocorticoids
73
What does the zona reticularis of the adrenal cortex secrete?
Sex steroids
74
What does the medulla of the adrenal gland secrete?
Catecholamines
75
What are the main causes of primary adrenal insufficiency?
Addisons disease, congenital adrenal hyperplasia, adrenal TB, adrenal malignancy, meningococcal septicaemia
76
What are the main causes of secondary adrenal insufficiency?
Lack of ACTH stimulation, iatrogenic (steroid use). pituitary/hypothalamic disorders
77
What is Addison's disease?
Autoimmune destruction of adrenal glands
78
What are symptoms of Addison's disease?
Lethargy, weakness, N&V, weight loss, salt craving, bronzed skin, hypotension
79
What does the biochemistry show in Addison's?
Low sodium, High potassium
Hypoglycaemia
Metabolic acidosis
80
How is Addison's investigated?
Short synacthen test (cortisol remains low)
81
How is Addison's treated?
Hydrocortisone and fludricortisone
82
What are sick day rules for Addison's?
Double dose of hydrocortisone
83
How is an Addisonian crisis treated?
Hydrocortisone 100mg IV/IM
| 1 litre IV saline/saline with dextrose over 1 hour
84
What is congential adrenal hyperplasia?
Group of autosomal recessive disorders
85
How does CAH present?
Virilisation in females, precocious puberty in males, salt wasting crisis
86
How is CAH treated?
Glucocorticoid and mineralocorticoid replacement
| Timely recognition important to allow growth
87
What is Cushing's syndrome?
Chronic glucocorticoid excess, loss of HPA negative feedback and loss of cortisol circadian rhythm
88
When is cortisol highest?
In the morning
89
What are ACTH depdendent causes of Cushings syndrome?
```
Cushings disease (Pituitary adenoma)
Ectopic ACTH (SCLC)
```
90
What are ACTH independent causes of Cushing's?
Adrenal adenomas, iatrogenic (steroids), Carney complex, McCune-Albright Syndrome
91
What are symptoms of Cushing's?
Weight gain, mood change, gonadal dysfunction, proximal myopathy
92
What are signs of Cushing's?
Striae, central obesity, moon face, easy bruising
93
What is the investigation for Cushings?
Overnight dexamethasone suppression test
94
How is Cushings treated?
Depends on cause
Iatrogenic - stop steroids
Cushings disease - transphenoidal adrenalectomy
95
What is primary aldosteronism?
Autonomous production of aldosterone independent of its regulators
96
What are the main causes of primary aldosteronism?
Bilateral adrenal hyperplasia
| Conn's syndrome (adrenal adenoma)
97
How does primary aldeosteronism present?
Asymptomatic or signs of hypokalaemia, increased BP, LVH, atheroma
98
What does the biochemistry show in primary aldosteronism?
High sodium
| Low potassium
99
What investigation should be done in primary aldosteronism?
Aldosterone:renin ratio
| Saline suppression test
100
How is Conn's treated?
Laparoscopic adrenalectomy
101
How is bilateral adrenal hyperplasia treated?
Spironolactone
102
What is phaeochromocytoma?
Rare catecholamine producing tumour in the adrenals
103
What is phaeochromocytoma associated with?
MEN, neurofibromatosis, Von-Hippel-Lindau
104
How does phaeochromocytoma present?
Headache, sweating, tachycardia, flushing, weight loss,, hypertension, hyperglycaemia, lactic acidosis
105
What investigations are important in phaeochromocytoma?
24hr urinary collection of metanephrines/catecholamines
106
What is the definitive treatment of a phaeochromocytoma?
Surgical excision
107
What treatment is given before surgery for a phaeochromocytoma?
Alpha and beta blockade (alpha blockade given first)
108
What is diabetes?
A chronic condition characterised by elevated glucose levels
109
What is type 1 diabetes?
Autoimmune destruction of type 1 pancreatic beta cells which produce insulin
Results in an absolute deficiency of insulin and raised glucose levels
110
What are symptoms of type 1 diabetes?
Classic triad of polyuria, polydipsia and weight loss. Fatigue, blurred vission, candida. May present as DKA in younger patients
111
What is type 2 diabetes?
Relative insulin deficiency due to an excess of adipose tissue
112
What are the symptoms of type 2 diabetes?
Asymptomatic or may present with complications e.g. MI, vision issues, kidney failure
113
What is pre-diabetes?
Term used to describe patients who do not yet reach the criteria for T2DM
114
How should pre-diabetes be managed?
Require monitoring and lifestyle interventions
115
What is maturity onset diabetes of the young (MODY)?
Autosomal dominant inherited disorder affecting insulin production
116
What does MODY result in?
Younger patients with a T2DM picture
117
How is MODY treated?
Sulphonylureas
118
What is latent autoimmune diabetes of adults (LADA)?
Autoimmune destruction of B islet cells occuring in young adults aged 25-40
119
What may be a clue that the patient has LADA not T2DM?
Inadequate control on T2DM drugs
120
If a patient has symptoms of diabetes, what criteria is needed for a diagnosis of diabetes?
Fasting glucose more than 7 OR
| Random glucose/2 hr post OGTT of over 11.1
121
If a patient has no symptoms, what criteria is needed for a diagnosis of diabetes?
Fasting glucose more than 7 OR
random glucose/2hr post OGTT over 11.1
TWICE ON 2 SEPARATE OCCASIONS
122
What is impaired fasting glucose defined as?
Fasting glucose between 6.1 and 7
123
What should patients with an impaired fasting glucose be offered?
OGTT to rule out diabetes
124
What is an impaired glucose tolerance?
Between 7.8 and 11.1 on OGTT
125
What sort of insulin regime is best for mimicking the bodys natural secretions of insulin?
Basal bolus
126
How are basal bolus doses of insulin divided up?
50% basal and 50% prandial
127
How many units of insulin per Kg are started to begin with?
0.3 per kg
128
How often should self glucose monitoring be done?
4 times/day - before each meal and before bed
129
What should be the glucose targets for T1DM before meals?
4-7mmol/L
130
What should be the glucose targets for T1DM 1-2hrs after meals?
<10mmol/L
131
What does HbA1C measure?
Glycosylated haemoglobin
132
What should be the aim for HbA1C?
48mmol/mol
133
What are side effects of insulin therapy?
Hypoglycaemia
| Lipodystrophy
134
What is the first line treatment for T2DM?
Metformin
135
How does metformin work?
Increases insulin sensitivity, decreases gluconeogenesis and carbohydrate absorption
136
How does metformin affect weight?
Causes weight loss
137
Does metformin cause hypos?
No
138
What are side effects of metformin?
GI upset, reduced B12 absorption, lactic acidosis
139
When is metformin contraindicated?
End stage CKD
140
How do sulphonylureas work?
Increase insulin secretion
141
How do sulphonylureas affect weight?
Cause weight gain
142
Do sulphonylureas cause hypos?
Yes
143
What are examples of sulphonylureas?
Gliclazide, gliblenclamide, glipizide
144
How do SGLT-2 inhibitors work?
Block glucose reabsorption in the proximal kidney tubule
145
How do SGLT-2 inhibitors affect weight?
Cause weight loss
146
Do SGLT-2 inhibitors cause hypos?
No
147
What are side effects of SGLT-2 inhibitors?
UTIs, genital thrush
148
What are examples of SGLT-2 inhibitors?
Dapagliflozin - 'gliflozins'
149
How do DPP-4 inhibitors work?
Propagate the effects of the incretin system
150
How do DPP-4 inhibitors affect weight?
Neutral
151
Do DPP-4 inhibitors cause hypos?
No
152
What are side effects of DPP-4 inhibitors?
Nausea, pancreatitis
153
What are examples of DPP-4 inhibitors?
Sitagliptin
154
How do thiazolidinedones work?
Enhance effects of insulin at target sites
155
How do thiazolidinedones affect weight?
Gain
156
Do thiazolidinedones cause hypos?
Yes
157
What are side effects of thiazolidinedones?
Fluid retention, hepatotoxicity, bone fractures
158
When are thiazolidinedones contraindicated?
CCF, osteoporosis, over 65s
159
What are examples of thiazolidinedones?
Pioglitazones
160
How do GLP-1 agonists work?
Propagate natural insulin response
161
How do GLP-1 agonists affect weight?
Cause weight loss
162
Do GLP-1 agonists cause hypos?
No
163
What is an example of a GLP-1 agonist?
Exenatide
164
What is gliclazide?
Sulphonylurea
165
What is dapagloflozin?
SGLT-2 inhibitor
166
What is sitagliptin?
DPP-4 inhibitor
167
What is pioglitozone?
Thiazolidinedone
168
What is exentaide?
GLP-1 agonist
169
What is the HbA1C target in T2DM?
53mmol/mol or less
170
How long should a diabetic drug be trialled for before discontinuing/introducing a new drug?
3-6 months
171
How does peripheral diabetic neuropathy present?
Symmetrical sensory neuropathy, glove and stocking numbness, tingling, worse at night
172
How is peripheral neuropathy in diabetics treated?
Simple analgesia then neuropathic pain agents
173
How does autonomic neuropathy present in diabetics?
Erectile dysfunction, gastroparesis, sweating, increased HR
174
What focal neuropathies can be a complication of diabetes?
Carpal tunnel, Bells palsy
175
What changes can be found in diabetic feet?
Neuropathic and ischameic changes
176
What sort of ulcers are common in diabetic foot disease?
Typically painless, punched out ulcer, overlying a callus
177
What treatment is important in diabetic foot disease?
Regular chiropady to remove calluses, check for infections, relieve any high pressure areas
All help to prevent amputation
178
What is diabetic nephropathy also known as?
Kimmelsteil Wilson syndrome
| Nodular glomerulosclerosis
179
Why doe diabetic nephropathy occur?
Poor glycaemic control first leads to renal hypertrophy and increased eGFR
> increased pressure causes capillary damage and sclerosis
> results in hypertension and further decline in function
180
What screening test is done in diabetic neprhopathy?
Albumin:creatinine ratio (ACR)
181
How often should patients ACR be screened in diabetes?
Annually
| From aged 12 in T1DM and from diagnosis in T2DM
182
How is diabetic nephropathy treated?
All patients with microalbuminuria are placed on ACEi/ARB regardless of BP
183
What changes are seen in diabetic retinopathy?
Blot haemorrhages, cotton wool spots, hard exudates
184
How often should a diabetic patient without diabetic retinopathy be screened?
Every 2 years
185
How often should a diabetic patient with diabetic retinopathy be screened?
Every year
186
How are macrovascular complications of diabetes prevented?
All diabetics over 40 should be on a statin
187
What causes diabetic ketoacidosis?
Insulin deficiency resulting in an osmotic diuresis and rapid lipolysis
188
What blood gas is seen in DKA?
Metabolic acidosis
189
What may precipitate DKA?
Infection, missed insulin doses, MI
190
What are symptoms of DKA?
Abdominal pain, polyuria, polydipsia, dehydration, kussmaul breathing, acetotic breath
191
What biochemical perameters are needed for diagnosis?
Blood glucose >11 (or known diabetes)
Ketones >3/++ on urine dip
Bicard <15 or pH <7.3
192
How is DKA managed?
Fluids - 0.9% NaCl bolus
Insulin IV infusion - 0.1 unit/kg/hr
When BG <15, add dextrose to the bag
Add potassium to the bag to correct hypokalaemia
193
What are complications of DKA?
Gastric stasis, VTE, arrythmias, AKI
194
What is hypoglycaemia?
Plasma glucose below 3mmol/L
195
What are symptoms of hypoglycaemia?
Sweating, anxiety, hunger, tremor, palpitations, dizziness, confusion, drowsiness
196
What is the cause of hypoglycaemia?
Fasting (commonly due to insulin, sulphonylureas etc), Post-prandial (T2DM, after gastric surgery)
197
How is hypoglycaemia treated if the patient is concious?
10-20g of oral sugar if able to taken then long acting carb (e.g. toast)
198
How is hypoglycaemia treated if the patient is unconcious?
```
IV glucose (150ml of 10%) or
IM glucagon
```
199
What is the main cause of acromegaly?
Excress growth hormone due to a pituitary adenoma
200
What are features of acromegaly?
Coarse facial appearance, spade like hands, large tongue, interdental spaces, excessive sweating, headache, bitemporal hemaniopia
201
How is acromegaly investigated?
OGTT and measure GH levels (GH levels will not be suppressed in acromegaly)
202
How is acromegaly treated?
Transphenoidal surgery
| Somatostain analogue - octreotide
203
Which hormones are reduced in stress responses?
Insulin, testosterone, oestrogen
204
What biochemistry is seen in an addisonian crisis?
Hyponatraemia
Hyperkalaemia
Hypoglycaemia
205
What are features of Kleinfelters?
Small testes, tall, gynaecomastia, infertility (47XXY)
206
What are features of Kallmans?
Anosmia, infertility - due to failure of GnRH secretion
207
What can cause HbA1C to be underestimated?
Sickle cell anaemia
G6PD deficiency
Hereditary spherocytosis
208
What can cause HbA1C to be overestimated?
Vitmain B12/Folate deficiency
Iron deficient anaemia
Splenectomy
209
Which patients on insulin do NOT have to inform the DVLA?
People on temporary treatment for 3 months or less and gestational diabetes
210
What HBA1C is indicative of pre-diabetes?
42-47mmol/mol
211
What blood gas does Cushings cause?
Hypokalaemia Metabolic Alkalosis
