Medicine - Endocrinology Flashcards
1
Q
What are the criteria for diagnosis of type 2 diabetes?
A
Either symptoms + 1 pos test result or no symptoms + 2 pos test results
Pos test thresholds:
- Fasting glucose >7.0
- OGTT >11.1
- Random glucose >11.1
- HbA1c > 6.5%/ 48mmol/L
2
Q
What are the test ranges for impaired gluose tolerance and impaired fasting glucose?
A
IGT: OGTT/random = 7.8-11.1; HbA1c = 42-47
IFG = 6.1-7.0
3
Q
What is the classic triad of symptoms of type 2 diabetes?
A
Polydipsia
Polyuria
Fatigue
4
Q
Recall 2 possible consequences of diabetic neuropathy and drugs that can be used to manage each of these possibiities
A
- Vagal neuropathy –> gastroparesis: domperidone/ metoclopramide
- Neuropathic pain: amitryptiline, duloxetine, gabapentin, pregabalin
5
Q
Summarise the pathogenesis of diabetic foot
A
- Peripheral arterial disease reduces O2 delivery –> intermittent claudication
- Neuropathy –> loss of sensation, eventually Charcot’s foot
6
Q
What is Charcot’s foot?
A
Rare consequence of T2DM in which foot becomes rocker-bottomed
7
Q
Recall some ways in which diabetic foot can be screened for, and the frequency with which these tests should be done
A
Screening should be done annually
Test for ischaemia: palpate the dorsalis pedis and posterior tibial pulse
Test for neuropathy with 10g monofilament test
8
Q
How should diabetic nephropathy be screened for?
A
Yearly albumin:creatinine ratio
Microalbuminuria is the first sign of diabetic nephropathy
9
Q
What is the best management for diabetic nephropathy?
A
ACE inhibitors
However, these are toxic in AKI so eGFR needs to be monitored
10
Q
How big a drop in eGFR would warrant stopping an ACE inhibitor in a diabetic patient?
A
> 20%
11
Q
Why is an initial drop in eGFR expected when starting patients on an ACE inhibitor?
A
Dilate the efferent arteriole
12
Q
Recall 3 things that may cause a falsely high HbA1c
A
Alcoholism
B12 deficiency
Iron deficiency anaemia
13
Q
What is the BM target for T1DM patients who are monitoring BMs throughout the day?
A
Waking target: 5-7mmol/L
Rest of the day: 4-7mmol/L
14
Q
Recall the names of 2 long-acting insulins
A
Lantus
Glargine
15
Q
When are BD mixed regimens of insulin given?
A
Breakfast and dinner
16
Q
Name a diabetes prevention programme
A
DESMOND
Diabetes education + self-management: ongoing and newly diagnosed
17
Q
Recall some possible risk-factor modifying therapies that can be used in diabetes mellitus
A
Aspirin 75mg OD
Atorvastatin 20mg OD
Antihypertensives
18
Q
What is the maximum dose of metformin?
A
2g/day
19
Q
Recall 4 important side effects of metformin
A
Appetite suppression
B12 deficiency (due to reduced absorption)
Lactate acidosis
GI upset
20
Q
How can you manage GI upset that is due to metformin?
A
Change immediate release to a modified release mechanism
21
Q
When should dual therapy be considered in type 2 diabetes?
A
If HbA1c >58/ 7.5%
22
Q
What are the options for dual therapy for type 2 diabetes?
A
Metformin + 1 of:
- Sulphonylurea
- Thiazolidinediones
- Gliptins
- SGLT2 inhibitors
23
Q
Recall 2 examples of sulphonylureas
A
Glibenclamide
Gliclazide
24
Q
Recall an example of a thiazolidinedione
A
Pioglitazone
25
Recall an example of a gliptin drug
Sitagliptin
26
What is the mechanism of action of gliptins?
DPP4 inhibitors
27
Recall an example of a SGLT2 inhibitor
Empagliflozin
28
Recall 2 important side effects of sulphonylureas
Weight gain
Hypoglycaemia
29
What sort of diabetes drug is MODY most sensitive to?
Sulphonylureas
30
What is the inheritance pattern of MODY?
Autosomal dominant
31
MODY must be diagnosed before what age?
25
32
What is the best investigation to confirm the diagnosis of MODY?
C peptides
33
What is the most common type of MODY, and which gene mutation causes it?
MODY 3
Mutated HNF-1 alpha
34
What is LADA?
Latent autoimmune diabetes in adults
Late onset T1DM in 20-50yo, no family history
35
What are the 2 best investigations for confirming the diagnosis of LADA?
GAD Abs
C peptide (will be low)
36
What 3 things are required to diagnosis DKA?
Diabetes, Ketones, Acidosis
Diabetes - BM >11.1
Ketones - >3
Acidosis - pH <7.3
37
Recall 4 common causes of DKA
Missed insulin
Trauma
Infection
EtOH
38
What 3 investigations are most useful for assessing the extent of the damage done by a DKA acutely?
ABG
ECG
U&Es
39
Recall the 5 main principles of managing DKA acutely
1. Fluids
2. Insulin
3. Potassium (run KCl in NaCL bag)
4. 10% dextrose (when BM < 15)
5. VTE prophylaxis (very dehydrated)
40
What dose of insulin should be started in DKA vs HHS?
DKA: 0.1U/kg/hr
HHS: 0.5U/kg/hr
41
Recall the 3 biochemical criteria used to diagnose HHS
pH >7.3
Osmolarity >320mmol/L
BM >30
42
Over what time period does HHS develop?
Over a few days
43
Recall the 3 components of HHS management
1. Fluids
2. Monitoring (ensure Na+ is not corrected too quickly)
3. Insulin
44
Recall 2 differentials for someone whose TFTs show low TSH and low T4
Secondary hypothyroidism
Sick euthyroid
45
Recall the Thy classification
Thy 1 = unsatisfactory sample (1c = cyst)
Thy 2 = benign
Thy 3 = atypia of undetermined significance
Thy 4 = Suspicious of malignancy
Thy 5 = malignancy
46
What classification system is used to classify thyroid nodules?
Thy classification
47
What are the 4 histological types of thyroid cancer
Anaplastic
Medullary
Papillary
Follicular
48
Which type of thyroid cancer is associated with a raised calcitonin?
Medullary
49
Recall 2 differentials for low uptake hyperthyroidism
Sub-acute (De Quervain's) thyroiditis
Postpartum thyroiditis
50
Recall 3 differentials for high uptake hyperthyroidism
Grave's disease
Toxic multinodular goitre
Single toxic adenoma
51
Recall 7 signs of thyroid eye disease
Mnemonic = NO SPECS
No signs or symptoms sometimes OR
Only signs (eg upper lid retraction) OR
Signs AND symptoms:
Proptosis
Extra-ocular muscle pathology
Corneal involvement
Sight loss due to optic nerve involvement
52
Why might eye movement be restricted in thyroid eye disease?
Rectus thickening restricts movement
53
What is the best preventative measure to prevent Grave's disease?
Stop smoking
54
Which subtypes of MEN are associated with medullary thyroid cancer?
2A and 2B
55
Recall the management of Grave's disease
1st line:
- Propranolol (NOT bisoprolol)
- Anti-thyroid drug eg carbimazole or propylthiouracil OR
- If unlikely to respond to ATDs, radioiodine (I-131)
56
Recall 2 possible side effects of radioiodine
Hypothyroidism
Thyroid storm
57
Recall how a patient should be prepared for thyroidectomy
1. Need to be euthyroid on medication
2. Laryngoscopy to check vocal cords
3. Either thionamides or propranolol
Stop thionamides (PTU) 10 days before surgery as it increases vascularity
58
Recall some symptoms of a thyroid storm
Hyperthermia
Tachycardia
Jaundice
Altered mental state
Cardiac (AF/high-output CF)
59
How should a thyroid storm be managed?
IV propranolol --> Thionamides (PTU)
Hydrocortisone --> iodine
60
What is the most common cause of primary hypothyroidism in the UK?
Hashimoto's
61
What is Riedel’s thyroiditis
Hypothyroidism caused by chronic inflammatory thyroid gland fibrosis
62
Recall 2 drugs that can cause hypothyroidism
Lithium
Amiodarone
63
What is the starting dose of levothyroxine?
50-100mcg
64
How long after starting levothyroxine should the TFTs be checked?
8-12 weeks
65
Recall 2 medications that interact with levothyroxine
Iron
CaCO3
66
Recall 4 features of myxoedema coma
Hypothermia
Hyporeflexia
Bradycardia
Seizures
67
How should myxoedema coma be managed?
IV thyroxine
IV hydrocortisome
IV fluids
68
What are the most common causes of Addison's disease?
In the UK: autoimmune adrenal failure
Worldwide: TB
69
Recall 2 ways that Addison's/adrenal failure can be investigated for
1. 9am cortisol
2. Short synACTHen test
70
Recall 3 possible cause of an Addisonian crisis (different from Addison's disease)
1. Adrenal haemorrhage (Waterhouse-Friderichson syndrome from meningococcaemia)
2. Steroid withdrawal
3. Sepsis/ surgery causing an acute exacerbation of chronic insufficiency (autoimmune/ TB)
71
How should an Addisonian crisis be managed?
Immediately:
- IM hydrocortisone 100mg STAT
- IV fluid bolus with glucose
Continuing management:
- IV fluids
- IV/IM hydrocortisone
72
What is the most common cause of Cushing's syndrome?
Glucocorticoid therapy
73
What are some differentials for ACTH-dependent Cushing's?
Cushing's disease (80% pituitary tumour)
Ectopic ACTH production
74
What are the possible causes of pseudo-Cushing's?
Alcoholism or severe depression
75
How can Cushing's and pseudo-Cushing's be differentiated?
Both will give a positive LDDST and 24hr free urinary cortisol
Can tell the difference between them with insulin stress test
76
Recall 2 screening tests for Cushing's
1. 11pm salivary cortisol (if low the cause is NOT Cushing's)
2. LDDST
77
How can the cause of Cushing's syndrome be confirmed?
Inferior petrosal sinus sampling
Catheter is fed into the jugular vein
78
What is Nelson's syndrome?
Possible complication of adrenalectomy
Removal of adrenal gland --> pituitary enlargement and very high ACTH
79
What is the most common electrolyte disturbance in Conn's syndrome?
Hypokalaemia
80
What is the best initial investigation in suspected Conn' syndrome?
Aldosterone: renin ratio
81
What are the best tests to determine the cause of hyperaldosteronism?
HR-CT and adrenal vein sampling
82
What are the possible causes of hyperaldosteronism?
1. Conn's syndrome
2. Renal artery stenosis
83
What will be the aldosterone: renin ration in Conn's syndrome vs renal artery stenosis?
Conn's: high
Renal artery stenosis: normal
84
What medications can be used to manage hyperaldosteronism?
Spironolactone and epleronone
85
What test can be used to diagnose diabetes insipidus?
Water deprivation test
86
Recall 2 possible renal and 2 non-renal causes of hypernatraemia
Renal: osmotic diuresis (T2DM) or diabetes insipidus
Non-renal: GI losses or sweat losses of water
87
What is the possible complication of correcting hypernatraemia too quickly?
Cerebral oedema
88
What is the possible complication of correcting hyponatraemia too quickly?
Central pontine myelinolysis
89
In which patients is a urine sodium measurement not reliable?
Those on diuretics
90
Recall some drugs that can cause SIADH
SSRIs and TCAs
Carbemazapine
Sulphonylureas (eg gliclazide)
PPIs (omeprazole/ lanzoprazole)
Opiates
91
Recall 2 causes of pseudohyponatraemia
Hyperlipidaemia
Hyperproteinaemia
92
Recall 2 drugs that can be used to treat SIADH
Demeocycline
Vaptans (eg tolvaptan)
93
Recall 3 classes of drugs that could cause hyperkalaemia
ARBs
ACE inhibitors
Aldosterone antagonists
94
Recall one antibiotic that can cause hyperkalaemia
Tacrolimus - it can reduce K+ excretion
95
Which type of renal tubular acisosis can cause hyperkalaemia
Type 4
96
Recall the management of hyperkalaemia
10mls 10% calcium gluconate
120mls 20% dextrose
Maybe:
10U insulin
nebulised salbutamol
If really bad:
Calcium risonium
97
For each of the following endocrine conditions, say whether they can cause hypo or hyperkalaemia:
- Addisson's
- Conn's
- Cushing's
Adisson's: Causes hyperkalaemia
Conn's: Causes hypokalaemia
Cushing's: Causes hypokalaemia
98
Which types of renal tubular acidosis can cause hypokalaemia (rarely)?
Types 1 and 2
99
Which hormone will likely be high in renal artery stenosis?
Renin
100
Describe the symptoms of hyper vs hypoclacaemia
Hypercalcaemia: bones, stones, abdominal groans, psychiatric moans
Hypocalcaemia: paraesthesia, muscle cramps, long QT
101
What is a 'pepperpot skull?
Radiological sign: Multiple tiny well-defined lucencies in the calvaria (top part of the skull) caused by resorption of trabecular bone in hyperparathyroidism
102
How should hypercalcaemia be managed?
IV fluids --> bisphosphonates
103
Recall the progression of multiple myeloma
(1) MGUS
(2) Smouldering myeloma
(3) Multiple myeloma
(4) B cell leukaemia
104
At what point in the myeloma progression does a patient get the symptoms of CRAB?
Not until it gets to multiple myeloma
105
What is the limit for monoclonal serum protein in MGUS?
Must be <30g/L
106
What is the limit for bone marrow plasma cells in MGUS?
<10%
107
Which type of immunoglobin will be high in myeloma?
IgG or IgA
If Waldenstrom's - IgM
108
What is the most useful form of imaging in myeloma?
Whole body low dose CT
109
Which CD markers are positive in immunotyping in myeloma?
CD38
CD138
CD56/58
110
What is the pathophysiology of refeeding syndrome?
Refeeding --> rise in insulin --> intracellular shift in phosphate --> hypophosphataemia
111
What are some symptoms of the refeeding syndrome?
Rhabdomyolysis
Low RR
Arrhythmia
Shock
Seizures
Coma
112
What is fibromuscular dysplasia?
Idiopathic, non-atherosclerotic, non-inflammatory disorder of arteries
2 subtypes:
- Renal artery
- Cervical artery
113
What are the symptoms of fibromuscular dysplasia?
Renal artery FMD: resistant hypertension
Cervical artery FMD: chronic migraines
114
What is the best investigation for assessing fibromuscular dysplasia?
Catheter angiography
115
What is the mainstay of management of fibromuscular dysplasia?
Stop smoking
Anti-platelets (clopidogrel)
Anti-hypertension (ACEi or ARB)
Surgery (surgical stenting)
116
Recall some causes of vitamin B12 deficiency
Autoimmunity
Atrophic gastritis
Gastrectomy
Malnutrition
117
Recall 2 drugs that can treat vitamin B12 deficiency
Cyanocobalamin IM
Hydroxocobalamin IM
118
Recall some causes of hypomagnesaemia
Diuretics/ PPIs
Diarrhoea
TPN
EtOH
Gitelman's/Barter's
Hypokalaemia, hypocalcaemia
119
What are the symptoms of hypomagnesaemia most similar to?
Hypocalcaemia
120
What are the ECG features of hypomagnesaemia most similar to?
Hypokalaemia
121
What is the threshold for giving IV magnesium sulphate as a Mg replacement, rather than just PO tablets?
Mg <0.4mmol/L
122
How should suspected SIADH be investigated?
1. Serum corrected calcium - must exclude hypercalcaemia secondary to hyperPTHism
2. Water deprivation test
123
What is the mechanism of hyponatraemia development in SIADH?
Increased water absorption in the collecting duct
124
What would be the main abnormality on TFTs in thyrotoxic crisis?
Marked elevation of free T4
125
What change in vision is caused by a lesion in the optic chiasm?
Bitemporal hemianopia
126
What change in vision is caused by a lesion in the optic tract?
Homonymous hemianopia
127
What change in vision is caused by a lesion in the optic radiation?
Superior quandrantopia
128
Give some examples of causes of metabolic acidosis with increased anion gap
DKA is a big one
Also: lactate acidosis, uraemia secondary to renal failure and salicylate/biguianide poisoning
129
In DKA, for how long should insulin infusion be continued before switching to SC insulin?
Until blood ketones <0.3mmol/L
130
How frequently should potassium be monitored in the acute setting of DKA being treated with an insulin infusion?
4 hourly
131
How should a known type 1 diabetic patient's insulin be managed when they are in DKA and require an insulin infusion?
Long acting basal insulin should be continued alongside the infusion as this simplifies the change from infusion to SC insulin in due course
132
Recall 4 side effects of carbimazole
Maculopapular rash
Bone marrow suppression leading to agranulocytosis
Pruritis
Jaundice
133
How should primary hyperaldosteronism due to BL adrenal hypertrophy be managed?
Spironolactone
134
What is the first drug to give in phaeochromocytoma?
Phenoxybenzamine
135
How should once daily insulin regimes be managed pre-operatively?
Reduced dose insulin on the day of the op and the day before
136
Why might someone get hyponatraemia post-SAH?
SAH can lead to SIADH
137
What is the best test for diagnosing phaeochromocytoma?
Plasma and serum catecholamines
138
How can a splenectomy affect blood sugar levels?
Can give a falsely high reading due to the increased life span of RBCs
139
What is the immediate management of pituitary apoplexy?
IV hydrocortisone
140
What is the treatment for malignant hyperthermia?
IV dantrolene
