Corrections - Endocrinology Flashcards
In a first unprovoked/isolated seizure, how long must patients not drive for?
Must inform DVLA and have 6 months off driving (seizure free).
If these conditions are not met then this is increased to 12 months.
What is 1ary hyperparathyroidism?
Excess secretion of PTH resulting in hypercalcaemia.
What is the most common cause of hypercalcaemia in outpatients?
1ary hyperparathyroidism
What is the most common cause of 1ary hyperparathyroidism?
Solitary adenoma (85%)
Symptoms of 1ary hyperparathyroidm?
‘Bones, stones, abdominal groans and psychic moans’ –> as causes hypercalcaemia
- polydipsia, polyuria
- depression
- anorexia, nausea, constipation
- peptic ulceration
- pancreatitis
- bone pain/fracture
- renal stones
- hypertension
Describe PTH, calcium, and phosphate levels in 1ary hyperparathyrodisim
- Raised calcium
- Low phosphate (due to raised PTH)
- PTH may be raised (or inappropriately given the raised calcium) normal
How does raised PTH affect phosphate levels?
Decreases phosphate
Infection with what bacteria is a CF-specific contraindication to lung transplantation?
Burkholderia cepacia
This gram-negative bacteria can colonise the lungs of people with cystic fibrosis and is often resistant to antimicrobial treatment. As a result, people who have contracted Burkholderia cepacia are unable to receive a lung transplant.
Diagnosis of diabetes in symptomatic vs asymptomatic patients?
Asymptomatic with ABNORMAL HbA1c or fasting glucose –> must be confirmed with a second abnormal reading before a diagnosis of type 2 diabetes is confirmed
Symptomatic –> can be diagnosed with HbA1c or fasting glucose reading
Describe serum c peptide levels in T1D?
Typically low
Give some causes of acanthosis nigricans
- T1DM
- Gastric cancer
- Obesity
- PCOS
- Acromegaly
- Cushing’s syndrome
- Hypothyroidism
- Drugs e.g. COCP
Pathophysiology of acanthosis nigricans?
insulin resistance –> hyperinsulinemia –> stimulation of keratinocytes and dermal fibroblast proliferation via interaction with insulin-like growth factor receptor-1 (IGFR1)
If unwell and a patient is on insulin, how should they change their insulin regime?
Continue insulin as normal but check blood sugars frequently.
Diabetes sick day rules: when unwell, if a patient is on insulin, they must NOT stop it due to the risk of diabetic ketoacidosis.
In type 1 diabetes, when is adding metformin considered on top of insulin therapy?
if the BMI >/= 25 kg/m2
What PMH is seen in 90% of those with malignant otitis externa?
Diabetes (90%() or immunosuppression
Can patients on insulin therapy hold an HGV license?
Yes - if they meet strict DVLA criteria
What is the Hba1c target for patients on a drug which may cause hypoglycaemia (eg sulfonylurea)?
53 mmol/mol
What is the most common cause of hypoglycaemia in diabetic patients?
Insulin or sulfonylurea treatment with an increase in activity or a missed meal or non-accidental overdose.
What are the most common causes of hypoglycaemia in NON-diabetic patients?
Mnemonic: EXPLAIN
E - Exogenous drugs e.g. alcohol, aspirin poisoning, quinine sulfate
P - Pituitary insufficiency
L - Liver failure
A - Addison’s disease
I - Islet cell tumours e.g. insulinoma
N - Non-pancreatic neoplasms
What vaccinations should be offered to patients with confirmed heart failure?
1) Annual influenza vaccine
2) Once-only pneumococcal vaccination.
Give the 5 main causes of pruritus
1) Liver disease
2) Iron deficiency anaemia
3) Polycythaemia
4) CKD
5) Lymphoma
Others:
- Diabetes
- Pregnancy
- Hyper- and hypothyroidism
- Skin conditions e.g. eczema, scabies, psoriasis
What other exam signs may be seen in liver disease?
- History of alcohol excess
- Stigmata of chronic liver disease: spider naevi, bruising, palmar erythema, gynaecomastia etc
- Evidence of decompensation: ascites, jaundice, encephalopathy
What other exam signs may be seen in iron deficiency anaemia?
- Pallor
- Other signs: koilonychia, atrophic glossitis, post-cricoid webs, angular stomatitis
What other exam signs may be seen in polycythaemia?
- Pruritus particularly after warm bath
- ‘Ruddy complexion’
- Gout
- Peptic ulcer disease
When is pruritus most common in polycythaemia?
After a warm bath
Describe the complexion in polycythaemia
‘Ruddy’
What other exam signs may be seen in CKD?
- Lethargy & pallor
- Oedema & weight gain
- Hypertension
How does CKD affect BP?
Can cause HTN
What other exam signs may be seen in lymphoma?
- Night sweats
- Lymphadenopathy
- Splenomegaly, hepatomegaly
- Fatigue
How often should insulin-dependent diabetics check their blood glucose if they drive?
Check before driving and every 2 hours regardless of if they have eaten or not
What is the mechanism of action of sitagliptin?
DPP-4 inhibitor
Hashimoto’s thyroiditis is associated with the development of what cancer?
MALT lymphoma
If a triple combination of drugs has failed to reduce HbA1c in T2D, what is recommended?
switching one of the drugs for a GLP-1 mimetic is recommended, particularly if the BMI > 35
What Abs are seen in Hashimoto’s?
Anti-thyroid peroxidase antibodies (anti-TPO)
What fasting blood glucose indicates T2D?
fasting glucose greater than or equal to 7.0 mmol/l
What random blood glucose (or after 75g oral glucose tolerance test) indicates T2D?
greater than or equal to 11.1 mmol/l
What is 1st line HTN medication in patients with T2D?
ACEi (regardless of age)
What is 1st line HTN medication in patients with T2D of black African or African-Caribbean?
ARB (e.g. losartan)
Which class of diabetes medication can cause SIADH?
Sulfonylureas
Patients with type I diabetes and a BMI > 25 should be considered for what in addition to insulin?
Metformin
Describe C-peptide levels in T1D
Low or undetectable
What is Buerger’s disease?
Who is it seen in?
Who - young people who smoke
What - inflammatory vasculitis
Presentation - symptoms similar to chronic limb ischaemia e.g. ischaemic ulcers
How often should T1 diabetics monitor their blood glucose?
at least 4 times a day, including before each meal and before bed
Deficiency in what vitamin can lead to subacute combined degeneration of the spinal cord?
B12 defiency e.g. due to gastrectomy (a consequence of removing of the intrinsic factor secreting cells that reside in the fundus and body of the stomach)
How much should patients with T1D aim to drinkduring during sick days?
aim to drink at least 3 L of fluid (5 pints) a day to prevent dehydration
CVS risk with rhuematoid arthritis?
Ischaemic heart disease.
What is impact on driving of having two hypoglycaemic episodes requiring treatment?
Must surrender their license - contact DVLA and stop driving immediately
What is thyroid eye disease?
Who does it affect?
Thyroid eye disease affects between 25-50% of patients with Graves’ disease.
It is thought to be caused by an autoimmune response against an autoantigen, possibly the TSH receptor –> retro-orbital inflammation which results in glycosaminoglycan and collagen deposition in the muscles.
What is the most important modifiable risk factor for the development of thyroid eye disease?
Smoking
What test can be used to localise the pathology resulting in Cushing’s syndrome?
High-dose dexamethasone suppression test
High-dose dexamethasone suppression test findings:
a) cortisol not suppressed
b) ACTH suppressed
What is likely diagnosis?
Cushing’s syndrome due to other causes such as adrenal adenoma
High-dose dexamethasone suppression test findings:
a) cortisol suppressed
b) ACTH suppressed
What is likely diagnosis?
Cushing’s disease (i.e. pituitary adenoma –> ACTH secretion)
High-dose dexamethasone suppression test findings:
a) cortisol not suppressed
b) ACTH not suppressed
What is likely diagnosis?
Ectopic ACTH syndrome
What is the most common cause of 1ary hyperparathyroidism?
Solitary adenoma
Blood test results in 1ary hyperparathyroidism?
a) calcium
b) phosphate
c) PTH
a) raised
b) low
c) raised or (inappropriately, given the raised calcium) normal
1st line investigation in suspected primary hyperaldosteronism?
A plasma aldosterone/renin ratio is the first-line investigation
Which diabetes medication often causes weight gain?
Sulfonylureas e.g. gliclazide
What is best test to diagnose Addison’s?
Short ACTH test
What is the most appropriate immediate step in management in DKA?
1L IV 0.9% sodium chloride over 1 hour
What is the most appropriate investigation for patients with increased urinary cortisol and low plasma ACTH levels?
CT adrenals
What are 2 clues in hyperglycaemic hyperosmolar state?
1) increased serum osmolarity
2) no ketosis
What drugs can cause gynaecomastia?
1) spironolactone (most common)
2) digoxin
3) cannabis
4) finasteride (5-a reductase inhibitor)
5) GnRH agonists (e.g. goserelin, buserelin)
6) cimetidine
7) oestrogens, anabolic steroids
What is the most common drug causing gynaecomastia?
Spironolactone
What is DKA resolution defined as?
1) pH >7.3 and
2) blood ketones < 0.6 mmol/L and
3) bicarbonate > 15.0mmol/L
Once DKA has resolved, the patient can be switched to SC insulin as long as they are eating and drinking normally.
What is a pituitary adenoma?
A pituitary adenoma is a benign tumour of the pituitary gland. They are common (10% of all people) but in most cases will never be found (asymptomatic) or are found as an incidental findings.
How can pituitary adenomas be classified according to size?
1) microadenoma: <1cm
2) macroadenoma: ≥1cm
How can pituitary adenomas be classified according to hormonal status?
1) secretory/functioning adenoma: produces an excess of a particular hormone
2) non-secretory/functioning adenoma: does not produce a hormone to excess)
What is the mot common type of pituitary adenoma?
Prolactinoma
What are the 4 most common types of pituitary adenomas?
1) prolactinoma
2) non-secreting adenoma
3) GH secreting adenoma
4) ACTH secreting adenoma
How can pituitary adenomas present?
1) excess of a hormone:
- Cushing’s disease due to excess ACTH
- acromegaly due to excess GH
- amenorrhea and galactorrhea due to excess prolactin
2) depletion of hormone(s):
- non-functioning tumours, therefore, present with generalised hypopituitarism
3) stretching of the dura within/around the pituitary fossa (causing headaches)
4) compression of the optic chiasm (causing a bitemporal hemianopia due to crossing nasal fibers)
What causes generalised hypopituitarism in non-functioning pituitary adenomas?
Due to compression of the normal functioning pituitary gland
What visual defect can be seen in a pituitary adenoma?
A bitemporal hemianopia due to compression of the optic chiasm.
What investigations are required in a pituitary adenoma?
1) a pituitary blood profile (including GH, prolactin, ACTH, FSH, LSH and TFTs)
2) formal visual field testing
3) MRI brain with contrast
What imaging is indicated in pituitary a adenoma?
MRI brain with contrast
1st line medical management of a prolactinoma?
Dopamine agonists (e.g., cabergoline or bromocriptine).
1st line medical mangement of GH-secreting adenomas?
1) somatostatin analogues (e.g., octreotide, lanreotide)
2) GH receptor antagonists (e.g., pegvisomant)
What is the 1ary surgical management for most pituitary adenomas?
Transsphenoidal surgery, especially for non-functioning and ACTH- or GH-secreting adenomas
What will women with hypothyroidism need to increase their thyroid hormone replacement dose by in pregnancy?
by up to 50% as early as 4-6 weeks of pregnancy
What is Trousseau’s sign?
Carpal spasm on inflation of BP cuff to pressure above systolic (due to occlusion of the brachial artery).
What is Trousseau’s sign a result of?
hypocalcaemia
In patients with T2DM, when should an SGLT-2 be introduced?
At any point they develop CVD, a high risk of CVD or chronic heart failure.
Which diabetes medications are associated with an increased risk of UTIs?
SGLT-2 inhibitors e.g. ertugliflozin
What is a myxoedema coma?
It is severe hypothyroidism leading to decreased mental status, hypothermia, and other symptoms related to slowing of function in multiple organs.
What is a normal fasting glucose?
<7 mmol/l
What is a normal random blood glucose or after 75g oral glucose?
<11.1 mmol/l
What are the main hormones that are deficient in Addison’s disease?
Cortisol & aldosterone
What are the 2 main medications in the management of Addison’s disease?
Hydrocortisone (to replace cortisol)
Fludrocortisone (to replace aldosteron)
What is the diagnostic criteria for HHS?
1) hypovolaemia
2) hyperglycaemia (>30 mmol/L)
3) serum osmolality >320 mosmol/kg
Give some causes of a lower than expected HbA1c level
Due to reduced RBC lifespan:
1) sickle cell anaemia
2) GP6D deficiency
3) hereditary spherocytosis
4) haemodialysis
Give some causes of a higher than expected HbA1c level
Due to increased RBC lifespan:
1) vit B12/folic acid deficiency
2) iron deficiency anaemia
3) splenectomy
What test can be used to distinguish between unilateral adenoma and bilateral hyperplasia in primary hyperaldosteronism?
Adrenal venous sampling (AVS)
What is the order of investigations in suspected 1ary hyperaldosteronism?
1) Plasna aldosterone/renin ratio (1st line)
2) High-resolution CT abdomen
3) Adrenal venous sampling (AVS)
What will the plasma aldosterone/renin ratio show in 1ary hyperaldosteronism?
Should show high aldosterone levels alongside low renin levels (negative feedback due to sodium retention from aldosterone).
Out of the following corticosteroids (fludrocortisone, hydrocortisone, prednisolone, dexamethasone & butamethasone), which one has:
a) Minimal glucocorticoid activity, very high mineralocorticoid activity
b) Glucocorticoid activity, high mineralocorticoid activity
c) Predominant glucocorticoid activity, low mineralocorticoid activity
d) Very high glucocorticoid activity, minimal mineralocorticoid activity
a) fludrocortisone
b) hydrocortisone
c) prednisolone
d) dexamethasone, betmethasone
Which diabetes drug carries an increased risk of leg ulcers and amputation?
What can be done to reduce this risk?
Canagliflozin (with a potential class effect across the SGLT-2 inhibitors).
To reduce this risk, good diabetic foot care and close monitoring are vital for diabetic patients taking SGLT-2 inhibitors.
What is the main type of thyroid cancer?
Papillary (70%)
Who is papillary thyroid cancer often seen in?
Young females
Prognosis of papillary thyroid cancer?
Excellent
Which type of thyroid cancer secretes calcitonin?
Medullary
What are the 3 main types of thyroid cancer?
1) papillary
2) follicular
3) medullary
What criteria must be met for patients on insulin to hold a driving license?
All patients taking insulin must inform the DVLA and:
1) there has not been any severe hypoglycaemic event in the previous 12 months
2) the driver has full hypoglycaemic awareness
3) the driver must show adequate control of the condition by regular blood glucose monitoring, at least twice daily and at times relevant to driving
4) the driver must demonstrate an understanding of the risks of hypoglycaemia
5) there are no other debarring complications of diabetes
What does increased homogenous uptake on a radioactive iodine uptake test suggest?
Grave’s disease
What is subacute thyroiditis (also known as De Quervain’s thyroiditis) thought to occur after?
A viral infection
How does Subacute thyroiditis (also known as De Quervain’s thyroiditis) typically present?
1) hyperthyroidism
2) painful goitre
3) raised ESR
4) globbaly reduced uptake on iodine-131 scan
What is sick euthyroid syndrome?
A condition in which serum levels of thyroid hormones are low in patients who have nonthyroidal systemic illness but who are actually euthyroid.
Typically seen in hospital inpatients.
Which 2 tablets can reduce the absorption of levothyroxine?
What can be done to minimise this?
1) iron tablets
2) calcium carbonate tablets
Take these & levothyroxine at least 4 hours apart.
NICE CKS have published guidance on the management of patients with subclinical hypothyroidism and recommend a ‘watch and wait’ approach in patients over the age of what?
80 years old
During major surgery, the body’s stress response is activated.
What hormones are increased?
What hormones are decreased?
Increased:
- catecholamines
- cortisol
- glucagon
- growth hormone
Decreased:
- insulin
- testosterone
- oestrogen
What is the most common cause primary hypoadrenalism in the UK?
Autoimmune destruction of the adrenal glands (Addison’s disease).
What is Addison’s disease?
Autoimmune destruction of the adrenal glands that results in reduced cortisol and aldosterone being produced.
Features of Addison’s disease?
- lethargy, weakness, anorexia, N&V, weight loss, ‘salt craving’
- hyperpigmentation (especially in palmar creases)
- vitiligo
- loss of pubic hair in women
- hypotension
- hypoglycaemia
- hyponatraemia & hyperkalaemia may be seen
- crisis: collapse, shock, pyrexia
What is a pheochromocytoma?
A rare catecholamine secreting tumour.
What is the rule of 10% in regard to a phaeochromocytoma?
bilateral in 10%
malignant in 10%
extra-adrenal in 10%
What is the most common site of an extra-adrenal phaeochromocytoma?
organ of Zuckerkandl, adjacent to the bifurcation of the aorta
Features of a phaeochromocytoma?
Usually episoidic:
1) HTN (90%)
2) Headaches
3) Sweating
4) Palpitations
5) Anxiety
1st line investigation in a phaeochromocytoma?
24 hr urinary collection of metanephrines (sensitivity 97%*)
What is the definitive management of a phaeochromocytoma?
Surgery.
The patient must first however be stabilized with medical management:
a) alpha-blocker (e.g. phenoxybenzamine), given before a;
2) beta-blocker (e.g. propranolol)
What is the key parameter to monitor in patients with hyperosmolar hyperglycaemic state?
Serum osmolality
What does impaired hypoglycaemia awareness occur as a result of?
Occurs due to neuropathy of parts of the autonomous nervous system
In a hypoglycaemic patient who is unconscious, what is 1st line?
IV glucose if there is access (100mL of 20% glucose IV)
What is the IV insulin infusion rate in DKA?
0.1 unit/kg/hour
