Endocrinology

Question 1

Describe the clinical features of hypoglycaemia

Answer 1

Autonomic – sweating, anxiety, hunger, tremor, palpitations, dizziness
Neuroglycopenic – confusion, drowsiness, visual trouble, seizures, coma

Question 2

List common causes of hypoglycaemia

Answer 2

Main cause – insulin or sulfonylurea treatment in a diabetic
EXogenous drugs
Pituitary insufficiency
Liver failure
Addison’s disease
Islet cell tumours
Non-pancreatic neoplasms

Question 3

Describe investigations for hypoglycaemia

Answer 3

BM during attack & lab glucose if in hospital
Take a drug history & exclude liver failure
72h fasting, bloods – glucose, insulin, c-peptide & plasma ketones if symptomatic

Question 4

Describe the treatment for hypoglycaemia

Answer 4

Conscious – 15-20g of quick-acting carbohydrate snack & recheck BM after 10-15 mins
Conscious but uncooperative – squirt glucose gel between teeth and gums
Unconscious patients – IVI glucose or give glucagon IV/IM

Question 5

Describe the clinical features of hyponatraemia

Answer 5

Early – headache, nausea, vomiting, general malaise
Late – confusion, agitation, drowsiness
Acute severe – seizures, respiratory depression, coma & death -> requires urgent treatment under senior supervision

Question 6

Describe investigations for suspected hyponatraemia

Answer 6

Full history & examination – drug history and hydration status
Urine osmolality, urine sodium, TFTs & assessment of cortisol reserve (0900 cortisol/synacthen test)

Question 7

Describe the management of hyponatraemia

Answer 7

Correct underlying cause
Asymptomatic chronic hyponatraemia – fluid restriction is often sufficient
Acute/symptomatic hyponatraemia – cautious rehydration with 0.9% saline (do not correct rapidly as cerebral pontine myelinolysis may occur)
Vasopressor receptor antagonists – promote water excretion without loss of electrolytes & are effective in treatment hypervolaemic & euvolaemic hyponatraemia
Emergency – seek expert help, consider hypertonic saline

Question 8

Describe the clinical features of hypernatraemia

Answer 8

Lethargy
Thirst
Weakness
Irritability
Confusion
Coma

Question 9

List causes of hypernatraemia

Answer 9

Fluid loss without water replacement
Diabetes insipidus
Osmotic diuresis
Primary aldosteronism
Iatrogenic eg. incorrect IV fluid replacement

Question 10

Describe the management of hypernatraemia

Answer 10

Give water orally if possible, if not give glucose
Use 0.9% saline IV if hypovolaemic

Question 11

Describe the clinical features of hypokalaemia

Answer 11

Muscle weakness
Hypotonia
Hyporeflexia
Cramps
Tetany
Palpitations
Light-headedness
Constipation

Question 12

Describe the treatment of hypokalaemia

Answer 12

Mild – give oral K+ supplement
Severe – give IV potassium, don’t give K+ oliguric

Question 13

Describe the clinical features of hyperkalaemia

Answer 13

Fast irregular pulse
Chest pain
Weakness
Palpitations
Light-headedness

Question 14

Describe the management of hyperkalaemia

Answer 14

Polystyrene sulfonate resin (calcium resonium) binds K+ in the gut, preventing absorption and bring K+ levels down over a few days
Emergency – calcium gluconate, insulin & glucose, salbutamol

Question 15

Outline the different causes of hypercalcaemia

Answer 15

Primary hyperparathyroidism – hypercalcaemia with non-suppressed PTH until proved otherwise
Malignancy – hypercalcaemia with suppressed PTH

Question 16

Describe the clinical features of hypercalcaemia

Answer 16

Asymptomatic
Tiredness, generalised aches & pains
Polyuria and polydipsia
Abdominal pain and constipation
Kidney stones

Question 17

Describe the investigations done for hypercalcaemia

Answer 17

Ca2+
PTH
ALP – high ALP reflects increased bone turnover
Renal ultrasound – nephrocalcinosis

Question 18

Describe the treatment of hypercalcaemia

Answer 18

Depends on the underlying cause
Hyperparathyroidism – parathyroidectomy if Ca2+ > 2.85 mmol/L, young; calcimimetic drugs (cinacalcet)

Question 19

Describe the common causes of hypocalcaemia

Answer 19

1) Post-surgical hypoparathyroidism
2) Vitamin D deficiency
3) Hypomagnesaemia

Question 20

Describe the clinical features of hypocalcaemia

Answer 20

Acute severe hypocalcaemia – laryngospasm, prolonged QT interval, seizures
Muscle cramps
Carpo-pedal spasm
Peri-oral and peripheral paraesthesia
Neuro-psychiatric symptoms

Question 21

Describe the treatment for hypocalcaemia

Answer 21

Calcium replacement
Reverse the underlying cause
Hypoparathyroidism – treated with 1-alfacalcidol or calcitriol
Magnesium deficiency – precipitating drugs should be stopped and IV magnesium replacement started

Question 22

Describe diabetes insipidus

Answer 22

Caused by vasopressin deficiency (cranial DI) or vasopressin resistance (nephrogenic DI)
Leads to passing of large volumes of dilute urine with profound unquenchable thirst

Question 23

Describe investigations to do for suspected diabetes insipidus

Answer 23

Low urine osmolality
High serum osmolality
Water deprivation test (measures urine osmolality):
1) cranial diabetes insipidus: low after deprivation, high after ADH
2) nephrogenic diabetes insipidus: low after deprivation, low after ADH
3) primary polydipsia: high after deprivation, high after ADH

Question 24

Describe the management for diabetes insipidus

Answer 24

If possible, treat underlying cause
Mild cases can be treated conservatively
Desmopressin (synthetic ADH) can be used in:
1) CDI to replace ADH
2) NDI in higher doses under close monitoring

Question 25

Describe Addison’s disease

Answer 25

Primary adrenal insufficiency Arises as a result of destruction of the adrenal gland OR genetic defects in steroid synthesis

Question 26

Describe the clinical presentation of Addison’s disease

Answer 26

Non-specific – fatigue, weakness, anorexia, weight loss, nausea Glucocorticoid loss – hypoglycaemia & increased pigmentation Mineralocorticoid loss – dizziness and postural hypotension Androgen deficiency – reduced libido and loss of axillary and pubic hair

Question 27

Describe the investigations for suspected Addison’s

Answer 27

Hyponatraemia, hyperkalaemia, raised urea, hypoglycaemia & mild anaemia Confirmatory tests – low 9am cortisol & simultaneously raised ACTH concentration -> Synacthen test is needed for confirmation

Question 28

Describe the management for Addison’s

Answer 28

Lifelong glucocorticoid and mineralocorticoid replacement -hydrocortisone and fludrocortisone Should double dose of glucocorticoid at times of illness Provided steroid emergency card

Question 29

Describe the clinical features of Cushing’s syndrome

Answer 29

Central obesity Dorso-cervical fat pad Increased roundness of the face Plethora (red face) Thin skin Easy bruising

Question 30

Describe investigations to do for suspected Cushing’s

Answer 30

24 hour urine free cortisol – elevated Low dose dexamethasone suppression test – failure to suppress cortisol Overnight dexamethasone suppression test – failure to suppress cortisol

Question 31

Describe the different causes of Cushing’s syndrome

Answer 31

3 potential causes are pituitary, adrenal or ectopic ACTH 1) ACTH is low, adrenal tumour is likely -> negative feedback by high cortisol levels 2) If ACTH is normal or high, diagnosis is pituitary or ectopic High dose DST leads to some cortisol suppression in Cushing’s disease but not in ectopic

Question 32

Describe the management of Cushing’s syndrome

Answer 32

Adrenal tumour – laparoscopic adrenalectomy Ectopic ACTH – appropriate treatment of the underlying malignancy and medical control of cortisol levels Cushing’s disease – trans-sphenoidal removal of the pituitary adenoma

Question 33

List common causes of hyperthyroidism

Answer 33

Graves’ disease – autoimmune disease & due to presence of TSH receptor stimulating antibodies Nodular hyperthyroidism – autonomous secretion of T3/T4 either from a solitary toxic nodule/numerous nodules situated within a toxic multi-nodular goitre Thyroiditis – inflammation causing a release of thyroxine

Question 34

Outline common clinical manifestations of hyperthyroidism

Answer 34

Weight loss with increased appetite Insomnia Irritability Anxiety Heat intolerance Palpitations Tremor

Question 35

List investigations to do for suspected hyperthyroidism

Answer 35

TFTs – increased T3, T4 & undetectable TSH Thyroid ultrasound Nuclear imaging (iodine uptake isotope scan) 1) Graves’ = uniform increased uptake 2) Nodular disease = increased uptake only in the autonomous nodule 3) Thyroiditis = absent uptake

Question 36

Describe the management for hyperthyroidism

Answer 36

Medication – carbimazole & propylthiouracil (NB: can cause agranulocytosis – urgent FBC if unexplained fever or sore throat) Surgery Radioactive iodine

Question 37

List the common causes of hypothyroidism

Answer 37

Hashimoto’s thyroiditis Pregnancy/post-partum Drugs – amiodarone & lithium

Question 38

Describe the common clinical features of hypothyroidism

Answer 38

Weight gain Cold intolerance Depression Constipation Fatigue

Question 39

List investigations done for suspected for hypothyroidism

Answer 39

TFTs – low T3/T4 & increased TSH TPO antibodies – strongly positive in Hashimoto’s thyroiditis

Question 40

Describe the treatment options for hypothyroidism

Answer 40

Thyroxine replacement