Endocrinology and clinical biochem Flashcards
1
Q
What is type I diabetes
A
Auto-immune desrtruction of beta-cells in the islets of langerhans of the pancreas causing insulin insufficiency and hyperglycaemia
2
Q
What is the typical presentation of type I diabetes
A
- polydipsia
- polyuria
- haematuria
- proteinuria
- weight loss
- personal/family history of autoimmune disease
3
Q
What fasting glucose is indicative of DM
A
> 7mmol/L
4
Q
What random glucose is indicative of DM
A
> 11mmol/L
5
Q
What HbA1c is indicative of DM
A
> 48mmol/L
6
Q
What lifestyle modifications can be advised for T2DM
A
- weight loss
- ecerxise
- smoking cessation
7
Q
What is the most widely prescribed drug for T2DM
A
metformin
8
Q
What is a serious possible side effect of metformin
A
lactic acidosis
9
Q
How does metformin work
A
It is a type of biguanide and is anti-hyperglycaemic
10
Q
Does metformin carry a risk of hypoglycaemia
A
Not if taken alone as it doesn’t increase insulin secretion
11
Q
Ehat are the names of some sufonylureas
A
Gliclazide, glipizide
12
Q
What is a possible side effect of sulfonylureas (eg gliclazide)
A
hypoglycaemia
13
Q
What should you look for when examining the skin of a patient who injects subcut insulin
A
lipohypertrophy
14
Q
what can you advise the patient to do to prevent lipohypertrophy
A
Switch injection sites regularly
15
Q
What happens to insulin levels when a patient continues injecting in a site with lipohypertrophy
A
The insulin uptake is poorer
16
Q
What are the two categories of diabetes complications
A
macrovascular and microvascular
17
Q
What are the ultra fast-acting subcut insulins
A
humalog and novorapid
18
Q
What are the long-acting recombinant human insulin analogues
A
insuline detemir
insulin glargin
19
Q
What is first line for long-acting basal insulin therapy
A
insulin detemir
20
Q
What are some common insulin regimens
A
- basal-bolus
- biphasic
- insulin pump
21
Q
Describe the basal-bolus regimen
A
One or more separate doses of intermediate- or long-acting insulin with short-acting bolus injections before or right after meals
22
Q
What should insulin-dependent diabetics remember when they are sick eg with the flu?
A
- insulin requirement often increases
- maintain calorie intake
- monitor blood glucose and ketonuria
23
Q
When would you admit a patient who is a insulin-dependent with the flu
A
if they are vomiting, dehydrated, ketotic, a child or pregnant
24
Q
What is the target blood pressure for diabetic patients
A
<135/85mmHg
25
What are some macrovascular complications of diabetes?
* coronary artery disease
* peripheraly artery disease
* stroke
26
How should you manage macrovascular risk in diabetes?
* lifestyle advice
* atorvastatin
* manage complications individually
27
What are some microvascular diabetes complications
* retinopathy
* cataracts
* nephropathy
* neuropathy
* diabetic foot
28
What are the types of diabetic neuropathy?
* autonomic neuropathy
* painful diabetic neuropathy
* sensory loss
29
What are some types of autonomic diabetic neuropathy?
* gastroparesis
* bladder emptying issues
* erectile dysfunction
30
How might diabetes result in the diabetic foor?
diabetic neuropathy and vascular disease
31
How do you tell the difference between vascular cause of diabetic foot and neuropathic cause
* Vascular may be pulseless
* Neuropathic will have decreased sensation
* Neuropathic may be more likely on pressure points
32
How do you screen for diabetic retinopathy?
diabetic eye screening programme
33
How do you treat diabetic nephropathy
ACE-inhibitors or angiotensin II receptor blockers if not tolerated
34
What is gestational diabetes
Glucose intolerance intolerance that is first recognised during pregnancy
35
What trimester is most common for diagnosis of gestational diabetes?
Third trimester
36
What are the risks to the mother of gestational diabetes
* pre-eclampsia
* increased risk of developing T2DM
* increased risk of developing cardiovascular disease
37
What are the risks to the foetus of gestational diabetes
* miscarriage
* pre-term labour
* congenital malformations
* macrosomia
38
What is macrosomia
A baby that is much larger than normal
39
Describe the treatment options for gestational diabetes
* lifestyle changes
* metformin
* insulin
40
What is secondary diabetes
Diabetes that results as a consequence of another medication, endocrine disease or hereditary disease
41
Give some examples of diseases that cause of secondary diabetes
* pancreatitis (acute/chronic)
* pancreatic cancer
* other endocrine disorders eg Cushing's and acromegaly
42
What is the most common drug cause of secondary diabetes
steroids
43
What are the two main forms of monogenic diabetes
* neonatal diabetes
| * maturity-onset diabetes of the young (MODY)
44
What is monogenic diabetes
rare forms of diabetes that result from mutations or changes in a single gene
45
What are the main diabetic emergencies?
* DKA
* hypoglycaemia
* HHS
46
What does HHS stand for
Hyperosmolar hyperglycaemic state
47
What is diabetic ketoacidosis
A consequence of insulin deficiency where there is breakdown of free fatty acids into ketone bodies which causes acidosis
48
What are ketones?
An energy substrate made in starvation or insulin deficiency
49
What is the classic presentation of diabetic ketoacidosis
* polyuria
* polydipsia
* Kussmaul breathing
* sweet smelling breath
* reduced GCS
50
What is Kussmaul breathing? What is it indicative of?
Deep rapid breathing indicative of patient trying to 'blow off' CO2 in acidosis
51
What investigations should be undertaken in an unwell diabetic?
* blood glucose
* venous blood gas
* blood ketones
* urine dipstick
52
What blood results (including VBG) would indicate ketosis?
* glucose >11mmol/L
* ketones >3mmol/L
* VBG signs of metabolic acidosis
53
How is DKA managed?
* Fluids!
* IV insulin infusion
* eventually give glucose in fluids
54
Why would you start giving glucose in fluids in DKA?
because the insulin reduces the ketones but can cause hypoglycaemia at the same time
55
What is HHS?
Hyperosmolar hyperglycaemic state is a hyperglycaemic state of hypovolaemia
56
What is the predominant problem in HHS
dehydration
57
What is the pathogenesis of HHS
Patients with T2DM may have enough insulin to stop ketone body production, but glucose still accumulates in the blood, leading to an osmotic diuresis
58
What is the onset period for HHS compared to DKA
Can be over many days, whereas DKA is a few hours or days
59
What is the management of HHS like
* fluid replacement
| * insulin infusion, although lower rates than in DKA
60
When do symptoms of hypoglycaemia start to appear? What glucose level?
<3.4mmol/L
61
What are some symptoms of hypoglycaemia?
* hunger
* pallor
* sweating
* palpitations
62
What severe symptoms of hypoglycaemia might a patient present with?
* seizures
* unconsciousness
* death
63
What treatment should unconscious patients with hypoglycaemia receive?
* IM glucagon or IV glucose infusion
64
What are some primary causes of hypothyroidism
* iodine deficiency
* hashimoto's thyroiditis
* surgery or medication
65
What are some symptoms of hypothyroidism?
* cold sensitivity
* weight gain
* lethargy
* constipation
* menstrual disturbances
66
What is the emergency that hypothyroidism might result in
myxoedema coma
67
What is the metabolically active form of thyroxin
T3
68
What are the bloods like in primary hypothyroidism
* high TSH
| * low T3/T4`
69
How is hypothyroidism treated
levothyroxine (T4)
70
What are symptoms of hyperthyroidism
* palpitations
* sweating
* heat intolerance
* weight loss
* anxiety
* diarrhoea
* a goitre
71
What are some complications of hyperthyroidism?
* heart failure
* atrial fibrillation
* Graves' ophthalmopathy
* thyrotoxicosis
72
What is the main cause of primary hyperparathyroidism
Graves' disease
73
What blood results indicate hyperthyroidism
Low TSH
| Elevated T3/T4
74
What drug therapy can be given for hyperthyroidism
* caribomazole
| * thyroxine may be required
75
What non-pharmacological therapy can be given for hyperthyroidism
* surgery
| * radioactive iodine
76
Why would radioactive iodine be contraindicated
in patients with Graves' ophthalmopathy it makes it worse
77
What is a possible complication of thyroid surgery
* hypothyroidism
* hypoparathyroidism
* bleeding
78
What is a toxic thyroid goitre?
A goitre associated with hyperthyroidism
79
How are thyroid goitres treated
* treat underlying pathology
| * surgery
80
What may be found on examination of a goitre in Graves'? Why?
a bruit may be heard because the goitre becomes very vascular
81
What would a diffusely enlarged and smooth goitre without bruit indicate?
Iodine deficiency
82
Does a thyroid goitre need to be investigated in pregnancy if there are no symptoms?
Not neccessarily, because the thyroid may enlarge for increased demand and then will receed after pregnancy
83
What investigation should be done for a nodular goitre?
fine needle aspiration and TFTs
84
What are causes of thyroid lumps?
* thyroid cysts
* follicular adenoma
* malignancy
* nodule of multinodular goitre
85
What is multinodular goitre
enlarged thyroid that contains many nodules of varying sizes
86
How is thyroid carcinoma treated?
* radioactive iodine
* radiotherapy
* chemotherapy
* surgery
87
What causes PTH release?
Low calcium levels
88
What does PTH do
* triggers bone resorption
* causes kidney reabsorption of Ca
* causes kidney production of calcitriol
89
What does calcitriol do
increases GI absorption of calcium
90
What elecrolyte abnormalities are found in hyperparathyroidism
hypercalcaemia
| hypophosphataemia
91
What are symptoms of hyperparathyroidism
* painful and fragile bones
* kidney stones
* cardiac arrhythmias
* confusion
* muscle weakness
* dehydration
92
What is the most common cause of hyperparathyroidism
parathyroid gland adenoma
93
What are malignant tumours of the parathyroid gland often associated with?
MEN (multiple endocrine neoplasia)
94
How is hyperparathyroidism investigated
* PTH levels
* serum calcium and phosphate
* U&Es
* x ray
95
What LFT might be elevated in hyperparathyroidism
Alk Phos
96
What medications may cause hypercalcaemia
* lithium
| * thiazide diuretics
97
What treatment can be given for primary hyperparathyroidism
* surgery
| * bisphosphonates, calcitonin, cinacalcet
98
What medical therapy can be used for primary hyperparathyroidism
* calcitonin
* cinacalcet
* bisphosphonates
99
What are complications of surgical removal of parathyroid glands
* hypocalcaemia
* recurrent laryngeal nerve injury
* bleeding
100
What causes secondary hyperparathyroidism
conditions that cause hypocalcaemia will result in increased PTH secretion, which if prolonged can cause the glands to enlarge
101
Give an example of a condition that causes hyperparathyroidism
* vitamin D deficiency or malabsorption
| * renal failure
102
What is tertiary hyperparathyroidism
If secondary hyperparathyroidism persists, the level of calcium required to inhibit PTH production is reset to a higher level which causes autonomous parathyroid gland activity
103
What is treatment of tertiary hyperparathyroidism
surgery
104
What condition often causes tertiary hyperparathyroidism
chronic kidney failure
105
What are the main causes of hypoparathyroidism
* surgery
* congenital deficiency - digeorge syndrome
* idiopathic hypoparathyroidism
106
What are the symptoms of hypoparathyroidism
* hand and feet parasthesia
* muscle cramps
* depression
* cardiac arrhythmias
107
What is Trousseau's sign? What condition causes it?
Blood pressure cuff on arm causes carpopedal spasm due to tetany of muscles in hands
Hypocalcaemia/hypoparathyroidism
108
What would the elecrolytes show in hypoparathyroidism
hypocalcaemia
| hyperphosphataemia
109
What are some causes of hypocalcaemia you should investigate
```
Hypoparathyroidism
Acute pancreatitis
Renal failure
Vitamin D3 deficiency
Alkalosis
Rhabdomyolysis
Drugs (eg bisphosphonates)
```
110
Does adrenal cortex insufficiency usually affect a specific layer?
It tends to affect the whole adrenal cortex rather than specific layers
111
What causes increased skin pigmentation in adrenal insufficiency?
increased ACTH levels
112
What effect does cortisol have on glucose
increases blood glucose levels
113
What triggers cortisol release
ACTH from the pituitary
114
What triggers aldosterone release
renin
115
What effect does aldosterone have
* increases sodium
* decreases potassium
* increases blood pressure
116
What does loss of aldosterone cause
* hyponatraemia
* hyperkalaemia
* hypovolaemia
* low blood pressure
* metabolic acidosis
117
What drugs are given in primary adrenal insufficiency?
hydrocortisone and fludrocortisone
118
What hormoen does fludrocortisone replace
aldosterone
119
What hormone triggers ACTH release
corticotrophin releasing hormone from the hypothalamus (CRH)
120
What are causes of primary adrenal insufficiency
* autoimmune (addisons)
* TB
* malignancy
121
What are symptoms of primary adrenal insufficiency
* fatigue
* confusion
* postural hypotension
* abdominal pain
* nausea and vomiting
* skin hyperpigmentation (especially around joints)
122
What are symptoms of an addisonian crisis
* back/abdo/leg pain
* vomiting and diarrhoea
* dehydration
* loss of consciousness
* hypotension
* hypoglycaemia
123
What is an addisonian crisis
When a trigger (often illness) causes chronic adrenal insufficiency to become acute
124
How is primary adrenal insufficiency diagnosed
* synthetic ACTH
| * cortisol levels monitored do not increase with ACTH
125
What would be the issue if synthetic ACTH did trigger appropriate cortisol levels were observed?
secondary adrenocortical insufficiency
126
What is the most common cause of hypopituitarism
treatment for hyperpituitarism
127
What are some causes of hypopituitarism
* compression
* infarct
* haemorrhage
* tumour
128
What is treatment for hypopituitarism
hormone replacement with careful monitoring
129
What investigations are required for hypopituitarism
* cranial nerve exam (for any focal deficits caused by compression)
* CT/MRI head
* hormone levels
* stimulation tests
130
What is the most common cause of Cushing's disease (if not taking cortisol)
pituitary adenoma
131
What are the possible causes of Cushing's (if not on exogenous cortisol)
* pituitary adenoma
* paraneoplastic syndrome
* adrenal tumour
132
What investigations should be undertaken for Cushing's
* CT/MRI head for pituitary adenoma
* PET-scan for other malignancies
* dexamethasone suppression test
133
What would results from a dexamethasone suppression test tell you?
* reduced ACTH indicates adrenal tumour
| * elevated ACTH = pituitary adenoma or paraneoplastic syndrome and requires imaging
134
How is Cushing's disease treated
surgery
135
What is a complication of surgery for Cushing's disease pituitary adenoma?
panhypopituitarism
136
What is acromegaly
excessive growth after skeletal epiphyseal closure due to increased growth hormone
137
What usually causes acromegaly
benign pituitary adenoma
138
What causes morbidity and mortality in untreated acromegaly
* cardiovascular disease
* cerebrovascular disease
* malignancy
139
What are some symptoms of acromegaly
* sweating
* headache
* clothes fit tightly
* amenorrhoea or impotence
* deep voice and slow speech
140
What is the most common functioning adenoma of the anterior pituitary gland
prolactinoma
141
How do prolactinomas present in females
* oligomenorrhoea
* amenorrhoea
* infertility
* galactorrhoea
142
How do prolactinomas present in males
* headache
* visual field defect
* erectile dysfunction
143
Why would prolactinomas cause visual field defects?
compression of optic chiasm
144
What can be given as a test to suppress GH secretion
oral glucose
145
What is PCOS
a condition of hyperandrogenism, oligo-/an-ovulation, and polycystic ovaries
146
What causes PCOS
raised LH levels
147
What are symptoms of PCOS
* oligo/amenorrhoea
* hirsutism or male pattern baldness
* infertility
* obesity
* insulin resistance
148
What dermatological finding is associated with PCOS
acanothosis nigricans
149
What tests and results are diagnostic of PCOS
* increased LH:FSH ratio
* increased androstenedione levels
* + 5 cysts found on ultrasound of ovaries
150
What are causes of gonadal failure in males
* Klinefelter
* cryptorchidism
* testicular torsion
151
What are causes of gonadal failure in females
* Turners
| * autoimmune ovarian failure
152
What is Klinefelter's?
46XXY
153
What is a phaeochromocytoma?
a rare cathecholamine-producing tumour of the adrenal medulla
154
What do phaeochromocytomas do?
secrete adrenaline and noradrenaline causing headaches and high blood pressure
155
Apart from the adrenal medulla, where might phaeochromocytomas occur?
the sympathetic ganglia beside the abdominal aorta
156
What is Conn's syndrome
An adenoma causing hyperaldosteronism
157
What are the effects of hyperaldosteronism?
* hypernatraemia
* hypokalaemia
* fluid retention
* alkalosis
* hypertension
158
What triad of symptoms should make you suspicious of Conn's?
* hypokalaemia
* hypertension
* alkalosis
159
What would be different in blood tests between hyperaldosteronism and renal artery stenosis?
renin would be raised in renal artery stenosis but low in hyperaldosteronism
