Medicine - Endocrinology Flashcards
What are the criteria for diagnosis of type 2 diabetes?
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
What are the test ranges for impaired gluose tolerance and impaired fasting glucose?
IGT: OGTT/random = 7.8-11.1; HbA1c = 42-47
IFG = 6.1-7.0
What is the classic triad of symptoms of type 2 diabetes?
Polydipsia
Polyuria
Fatigue
Recall 2 possible consequences of diabetic neuropathy and drugs that can be used to manage each of these possibiities
- Vagal neuropathy –> gastroparesis: domperidone/ metoclopramide
- Neuropathic pain: amitryptiline, duloxetine, gabapentin, pregabalin
Summarise the pathogenesis of diabetic foot
- Peripheral arterial disease reduces O2 delivery –> intermittent claudication
- Neuropathy –> loss of sensation, eventually Charcot’s foot
What is Charcot’s foot?
Rare consequence of T2DM in which foot becomes rocker-bottomed
Recall some ways in which diabetic foot can be screened for, and the frequency with which these tests should be done
Screening should be done annually
Test for ischaemia: palpate the dorsalis pedis and posterior tibial pulse
Test for neuropathy with 10g monofilament test
How should diabetic nephropathy be screened for?
Yearly albumin:creatinine ratio
Microalbuminuria is the first sign of diabetic nephropathy
What is the best management for diabetic nephropathy?
ACE inhibitors
However, these are toxic in AKI so eGFR needs to be monitored
How big a drop in eGFR would warrant stopping an ACE inhibitor in a diabetic patient?
> 20%
Why is an initial drop in eGFR expected when starting patients on an ACE inhibitor?
Dilate the efferent arteriole
Recall 3 things that may cause a falsely high HbA1c
Alcoholism
B12 deficiency
Iron deficiency anaemia
What is the BM target for T1DM patients who are monitoring BMs throughout the day?
Waking target: 5-7mmol/L
Rest of the day: 4-7mmol/L
Recall the names of 2 long-acting insulins
Lantus
Glargine
When are BD mixed regimens of insulin given?
Breakfast and dinner
Name a diabetes prevention programme
DESMOND
Diabetes education + self-management: ongoing and newly diagnosed
Recall some possible risk-factor modifying therapies that can be used in diabetes mellitus
Aspirin 75mg OD
Atorvastatin 20mg OD
Antihypertensives
What is the maximum dose of metformin?
2g/day
Recall 4 important side effects of metformin
Appetite suppression
B12 deficiency (due to reduced absorption)
Lactate acidosis
GI upset
How can you manage GI upset that is due to metformin?
Change immediate release to a modified release mechanism
When should dual therapy be considered in type 2 diabetes?
If HbA1c >58/ 7.5%
What are the options for dual therapy for type 2 diabetes?
Metformin + 1 of:
- Sulphonylurea
- Thiazolidinediones
- Gliptins
- SGLT2 inhibitors
Recall 2 examples of sulphonylureas
Glibenclamide
Gliclazide
Recall an example of a thiazolidinedione
Pioglitazone
Recall an example of a gliptin drug
Sitagliptin
What is the mechanism of action of gliptins?
DPP4 inhibitors
Recall an example of a SGLT2 inhibitor
Empagliflozin
Recall 2 important side effects of sulphonylureas
Weight gain
Hypoglycaemia
What sort of diabetes drug is MODY most sensitive to?
Sulphonylureas
What is the inheritance pattern of MODY?
Autosomal dominant
MODY must be diagnosed before what age?
25
What is the best investigation to confirm the diagnosis of MODY?
C peptides
What is the most common type of MODY, and which gene mutation causes it?
MODY 3
Mutated HNF-1 alpha
What is LADA?
Latent autoimmune diabetes in adults
Late onset T1DM in 20-50yo, no family history
What are the 2 best investigations for confirming the diagnosis of LADA?
GAD Abs
C peptide (will be low)
What 3 things are required to diagnosis DKA?
Diabetes, Ketones, Acidosis
Diabetes - BM >11.1
Ketones - >3
Acidosis - pH <7.3
Recall 4 common causes of DKA
Missed insulin
Trauma
Infection
EtOH
What 3 investigations are most useful for assessing the extent of the damage done by a DKA acutely?
ABG
ECG
U&Es
Recall the 5 main principles of managing DKA acutely
- Fluids
- Insulin
- Potassium (run KCl in NaCL bag)
- 10% dextrose (when BM < 15)
- VTE prophylaxis (very dehydrated)
What dose of insulin should be started in DKA vs HHS?
DKA: 0.1U/kg/hr
HHS: 0.5U/kg/hr
Recall the 3 biochemical criteria used to diagnose HHS
pH >7.3
Osmolarity >320mmol/L
BM >30
Over what time period does HHS develop?
Over a few days
Recall the 3 components of HHS management
- Fluids
- Monitoring (ensure Na+ is not corrected too quickly)
- Insulin
Recall 2 differentials for someone whose TFTs show low TSH and low T4
Secondary hypothyroidism
Sick euthyroid
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
What classification system is used to classify thyroid nodules?
Thy classification
What are the 4 histological types of thyroid cancer
Anaplastic
Medullary
Papillary
Follicular
Which type of thyroid cancer is associated with a raised calcitonin?
Medullary
Recall 2 differentials for low uptake hyperthyroidism
Sub-acute (De Quervain’s) thyroiditis
Postpartum thyroiditis
Recall 3 differentials for high uptake hyperthyroidism
Grave’s disease
Toxic multinodular goitre
Single toxic adenoma
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
Why might eye movement be restricted in thyroid eye disease?
Rectus thickening restricts movement
What is the best preventative measure to prevent Grave’s disease?
Stop smoking
Which subtypes of MEN are associated with medullary thyroid cancer?
2A and 2B
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)
Recall 2 possible side effects of radioiodine
Hypothyroidism
Thyroid storm