Endocrinology Flashcards
How is diabetes mellitus diagnosed?
Symptoms + 1 diabetes test result
No symptoms + 2 diabetes test results
Fasting >=7 mmol/L
HbA1c >=6.5%/ >=48mmol/L
OGTT >=11.1 mmol/L
Random >=11.1 mmol/L
What is impaired glucose tolerance?
random or OGTT >7.8 but <11.1
HbA1c 42-47
What is impared fasting glucose?
> 6.1 but <7.0
What are the symptoms of diabetes?
fatigue
polydipsia
polyuria
What are the complications of diabetes?
microvascular and microvascular micro: retinopathy nephropathy neuropathy - gastroparesis (vag. nerve neuropathy), neuropathic pain, peripheral neuropathy
macro:
cerebrovascular disease
cardiovascular disease
peripheral vascular disease
Why does diabetic foot happen?
Secondary to peripheral artery disease -> intermittent claudication
and neuropathy -> charcot foot
How is diabetic foot screened for?
annually (at least)
ischaemia - palpate dorsalis pedis and posterior tibial
neuropathy - 10g monofilament test
how is diabetic nephropathy screened for?
yearly ACr (albumin creatinine ratio) 1st - spot sample, if abnormal then use a morning sample
what is the first sign of diabetic nephropathy?
microalbuminuria
What is the management of diabetic nephropathy?
ACEi (protective in chronic but toxic in AKI)
Monitor eGFR: if drop >20% then stop ACEi
a small initial drop is expected
What may cause a falsely high HbA1c?
decreased destruction e.g. alcoholism, B12 deficiency, DA
What may cause a falsely low HbA1c?
SCD
How many times a day should BMs be monitored?
adult >=4x a day before meals and bed
child >=5x a day
What is the waking blood sugar target?
5-7mmol/L
What is blood sugar target at other points the day
4-7 mmol/L
How often is HbA1c monitored in T1DM?
Once every 3-6m
What is first line management of T1DM?
basal bolus regimen
Rapid = novo rapid/aspart
long acting = lantus/glargine
How should t1dm management be changed if the patient is sick?
continue normal insulin but increase monitoring to every 4 hours
may need to increase short acting insulin
What is 2nd line management of T1DM?
BD pre-mixed regimen (given at the start of breakfast and dinner, instead of TDS)
Intermediate + rapid acting
Intermediate + short acting
Give some examples of rapid acting insulin?
(Given at start of meal)
Novorapid (aspart)
Humalog (lispro)
Apidra (glulisine)
Give some examples of short acting insulin?
(Given 15-30 mins before meal)
Actrapid
Humulin S
FRII
Give some examples of intermediate acting insulin?
(Given OD/BD or as part of a mix)
Insulatard
Humulin I
Insuman basal
Give some examples of long acting insulin?
(Given OD)
Lantus (glargine)
Levemir (determir)
Tresiba (degludec)
What is a normal HbA1c?
20-42
When should conservative measures be initiated for T2DM?
If HbA1c >=42/ 6.0%
What HbA1c is pre-diabetes and how should it be managed?
42-48
refer to diabetes prevention programme
When should medical therapy be initiated for T2DM?
If Hba1c >=48 / 6.5%
What is medical management of T2DM
RF modification: aspirin, atorvastatin, anti HTN
1st line: metformin
2nd line: metformin + (sulphonylurea/thiazolidione/SGLT2/gliptin)
3rd line: triple therapy
4th: insulin
5th: metformin + sulphnylurea + GLP-1 analogue (exenatide)
When should dual therapy be initiated for T2DM?
If HbA1c rises to >58 mmol or >7.5%
What is target HbA1c in T2DM on single therapy?
48
What are the side effects of metformin?
appetite suppression, lactic acidosis, GI upset, reduced B12 absorption
What should be changed if GI upset on metformin?
switch from immediate release to modified release before trying new drugs
When is metformin contraindicated ?
eGFR <30
tissue hypoxia (MI, surgery)
alcohol abuse
What is T2DM HbA1c target on dual therapy?
53
Give some examples of sulphonylureas
gliclazide
glibenclamide
What are the side effects of suphonylureas?
weight gain
hypoglycaemia !!
Rarer:
SIADH
Hepatic dysfunction
BM suppression
What are sulphnylurea contraindications?
ketoacidosis
caution: high BMI, G6PDD
Give an example of a thiazolidione
pioglitazone
what are the side effects of thiazolidiones?
weight gain
abnormal LFTs
baldder cancer
osteoporosis
What are contraindications to thiazolidiones?
HF Bladder cancer (past/present)
Give an example of a gliptin?
sitagliptin
When are gliptins a good choice of second therapy?
when the patient is overweight
Contraindications to gliptins?
ketoacidosis
caution: eGFR <45
Give an example of an SGLT2 inhibitor?
empagliflozin
what are the side effects of SGLT2 inhibitors?
euglycaemic DKA, infections
fourniers gangrene
angioedema
SGLT2 inhibitors contraindications?
DKA,
eGFR <60 -> use gliclazide or sitagliptin instead
caution: UTI
When are SGLT2 inhibitors preferable?
encourage weight loss
improve cardiac outcomes
decrease admission rates of HF
Give some examples of triple therapy regimes for T2DM
- metformin + sulphonylurea + gliptin
- metformin + sulphonylurea + thiazolidione
- metformin + sulphonylurea/thiazolidione + SGLT2
2nd: insulin 1ml
When should a GLP-1 analogue be used?
if BMI>35 or if insulin unacceptable
What is MODY?
t2dm variant
<25yo
FHx (AD)
no ketosis
Ix MODY?
C-peptides
genetics
Mx MODY?
VERY SENSITIVE SULPHONYLUREAS
Types of MODY?
MODY2 (20%) - defective glucokinase
MODY3 (60%) - mutated HNF-1alpha, risk HCC
MODY5 (rare) - mutated HNF-1beta, liver cysts
What is LADA?
slowly progressive T1DM 20-50yo, no FHx
latent autoimmune diabetes in adults
ketones +ve
Ix for LADA?
GAD Abs, C peptide low
Mx of LADA?
oral hypoglycaemic -> insulin
What is the management of myxoedema coma?
yxoedema coma is a medical emergency requiring treatment with
IV thyroid replacement
IV fluid
IV corticosteroids (until the possibility of coexisting adrenal insufficiency has been excluded)
electrolyte imbalance correction
sometimes rewarming
What are some precipitating events of a thyroid storm?
thyroid or non-thyroidal surgery
trauma
infection
acute iodine load e.g. CT contrast media
what are the clinical features of thyroid storm?
fever > 38.5ºC
tachycardia
confusion and agitation - altered mental status
nausea and vomiting
hypertension
heart failure
abnormal liver function test - jaundice may be seen clinically
What is the management of thyroid storm?
symptomatic treatment e.g. paracetamol
treatment of underlying precipitating event
beta-blockers: typically IV propranolol
anti-thyroid drugs: e.g. methimazole or propylthiouracil
Lugol’s iodine
dexamethasone - e.g. 4mg IV qds - blocks the conversion of T4 to T3
what is subclinical hyperthyroidism?
TSH raised but T3, T4 normal
no obvious symptoms
What is the first line test for acromegaly?
serum IGF-1 level
if elevated then do OGTT
What are some causes of hypoglycaemia?
insulinoma - increased ratio of proinsulin to insulin
self-administration of insulin/sulphonylureas
liver failure
Addison’s disease
alcohol
nesidioblastosis - beta cell hyperplasia
What are some side effects of thyroxine?
hyperthyroidism: due to over treatment
reduced bone mineral density
worsening of angina
atrial fibrillation
What does thyroxine interact with?
iron, calcium carbonate
absorption of levothyroxine reduced, give at least 4 hours apart
Following a changes in thyroxine dose when should TFTs be checked?
after 8-12 w
How should the dose of thyroxine change for pregnant ladies?
omen with established hypothyroidism who become pregnant should have their dose increased ‘by at least 25-50 micrograms levothyroxine’* due to the increased demands of pregnancy. The TSH should be monitored carefully, aiming for a low-normal value
What are some common causes of hypothyroid?
Autoimmune (Hashimoto’s disease, atrophic)
Iodine deficiency
Thyroiditis (post-viral, post-partum)
Iatrogenic (thyroidectomy, radioiodine, drugs)
What is DKA?
bm>11
ketones >3
acidosis
rapid onset
Causes of DKA?
infection
alcohol
trauma
insulin missed
Ix DKA?
U&E ABG ECG BM Ketones
Mx DKA?
- fluids (500 ml bolus over 15m if SBP <90 then 1L NaCl over 1h)
- Insulin 0.1U/kg/hr
- Potassium
- 10% dextrose when BM<15 100ml/hour
- VTE prophylaxis
How are fluids administered in DKA?
1L over 1h 1L + kcl over 2h 1L + kcl over 2h 1L + kcl over 4h 1L + kcl over 4h 1L + kcl over 6h
What is a HHS?
t2dm
pH >7.3
osmolatiry >320 mOSM
BM >30mmol/L (massive hyperglycaemia non ketotic)
over a few days
Management of HHS?
- fluids - 3-6Lin 12h (1L 0.9% NaCl IV over 2h)
- monitor and avoid rapid correction Na
- Insulin 0.05u/kg/h sliding scale once BM stop dropping
what does rapid correction of Na in HHS causes?
osmotic demyelination syndrome
What are the types of thyroid cancer?
PFMA Papillary Follicular Medullary Anaplastic
what is seen in medullary thyroid cancer?
raised calcitonin (PTH antagonist)
Investigations for thyroid neck lump?
TFTs
Technetium uptake scan
Auto Abs (anti-TPO, anti-TG)
<1cm do not investigate
>1cm USS+ FNA
Management of thyroid Ca?
hemi thyroidectomy (-/+total) + Iodine-131 to kill remaining cells
yearly follow up: if +ve administer more I-131:
- I-123 whole body scans
thyroglobulin measurements/calcitonin if medullary
Remission for 7y -> fully cured and discharged
What are some causes of hyperthyroidism?
Graves (40-60%) Toxic multinodular goitre (30-50%) Single toxic adenoma (5%) subacute thyroiditis/viral thyroiditis/de Quervains (hyper -> hypo) Postpartum thyroiditis
What are some high uptake causes of hyperthyroidism?
Graves (40-60%)
Toxic multinodular goitre (30-50%)
Single toxic adenoma (5%)
What are some low uptake causes of hyperthyroidism?
subacute thyroiditis/viral thyroiditis/de Quervains (hyper -> hypo)
Postpartum thyroiditis
Features of Graves?
diffuse goitre
thyroid eye disease
thyroid acropatchy
pretibial myxoedema
Investigations for graves?
Anti TSH-R Abs (90%)
Anti-TPO Abs (75%)
increase homogenous radioactive uptake
Mx graves?
- propanolol (primary care), carbimazole (PTU 2nd line or pregnancy)
- radioiodine if unlikely remission with ATDs
- surgery - must be euthyroid
Types of treatment regime for Graves?
titration or block and replace
What is block and replace method?
6-9m fixed high dose carbimazole incl thyroxine
titration method for graves?
preferred method
12-18m dose on TFTs
reduce once euthyroid
what must be given to graves patients before surgery
must be euthyroid:
- thionamides (stop 10 days befre) or propanolol
- laryngoscopy (check vocal cords)
What can precipitate a thyroid storm?
surgery
radioiodine
S/S of thyroid storm?
hyperthermia, tachycardia, jaundice, altered GCS, cardiac (af, high output HF)
Mx thyroid storm?
IV Propanolol
thionamides (PTU)
hydrocortisone
Iodine (1-4 hours after ATDs)