Endocrinology Flashcards
What substance causes acromegaly
Abundance of Growth Hormone -> excessive IGF-1
What compound supresses GH
Somatostatin
Name a chronic condition associated with acromegaly
T2DM
Symptoms of Acromgealy
Large hands and feet
Macroglossia
Enlarged Heart
Fatigue
Erectile Dysfunction
First line investigation of Acromgealy
Serum IGF-1 levels
IF serum IGF-1 levels are raised, what should be done to confirm acromgealy
Oral Glucose Tolerance Test
After diagnosing acromgealy, what should be done and why
MRI to check the size of the pituitary tumour (or CT if contraindictaed)
First line treatment of acromegaly
Trans-sphenoidal surgery
Second Line: Pegovisomant (GH analogue) or Radiotherapy
What follow-up is given to patients with acromegaly
ECHO for cardiomegaly and colonoscopy every 5 years
What is Addison’s disease
Lack of adrenal function (glucocorticoid deficiency)
What is the most common cause of Addison’s
Auto-immune issues
Then:
Surgical removal
Trauma
TB
WaterhouseFriderichsen Syndrome
What injury can cause secondary adrenal insufficiency
Basilar skull fracture
Radiotherapy
Clinical features of Addison’s
Hypotension
Fatigue
GI symptoms
Syncope
Pigmentation
Vitiligo
What test is conducted to confirm Addison’s
SynACTHen test
Renin levels in Addison’s
High
Aldosterone levels in Addison’s
Low
What initial blood tests can be done to check for Addison’s
U and Es
Na+ levels in Addison’s
Low
K+ levels in Addison’s
High
Glucose levels in Addison’s
Low
Cortisol levels in Addison’s
Low
Treatment of Addisonian crisis
IV Fluids and Steroids
Glucose if hypoglycaemic
How is Addison’s managed
Hydrocortisone (to replace glucorticoids)
Fludrocortisone (to replace mineralocorticoids)
What cardiac condition is associated iwth carcinoid tumours
Pulmonary stenosis
Investigations for Cushing’s Syndrome
24 hour urinary free cortisol
Dexamethasone supression test
What invetsigations are needed to localise the cause of Cushing’s
Plasma ACTH levels
High dose dexamethasone supression test
Petrosal sinus sampling
MRI of the head
CT chest and abdo
Surgical management of Cushing’s
Pituitary tumour resection
Medical management of Cushing’s (usually first line to reduce size)
Metyrapone
or Ketoconazole/mifepristone
What defines Diabetes Insipidus
Urinarting more than 3L in 24 hours + Low osmolality (< 300 mOsm/kg)
Polydipisia and polyuria
Causes of Cranial Diabetes Insipidus
Head Trauma
Sarcoidosis
Meningitis
Sickle Cell Disease
Genetics
What metabolic disturbances can cause nephorgenic DI
Hypercalcaemia
Hypokalaemia
Hyperglycaemia
What genetic condition can cause nephrogenic DI
Wolfram’s Syndrome
First Line Investigation of DI
U+Es, blood glucose (to rule out T2DM)
What serum osmolality is seen in DI
> 295
What urine osmolality is seen in nephrogenic DI
<700
If diagnosis remains unclear from serum and urine osmolality, what test can be done
Fluid deprivation test
Management of cranial diabetes
Desmopressin
What serum levels should be monitored during desmopressin treatment and why
Na+ levels, as it causes hyponatraemia
Drug management of Nephrogenic DI
Thiazide diuretic
What blood glucose levels indicate DKA
> 11.1 mmol/L
What blood ketones indicate DKA
> 3 mmol/L
When ar eblood cultures indicated for DKA
If evidence of infection
When are ECGs indicated in DKA
To check for any changes if hypokalaemia is present
How should a DKA be managed in a patient who is alert
Try oral intake + SC Insulin
If a patient is vomiting, confused or dehydrated, how should DKA be managed
IV FLuids (10mls/kg 0.9% NaCl) + SC Insulin at 0.1 units/kg/hour 1 hour after starting IV Fluids.
If there is evidence of shock in a patient with DKA, how does management change
Increase IV fluid bolus from 10mls to 20mls/kg
What should be the first management steps for a DKA case where there is a coma
ABCDE approach
When should IV Insulin be stopped following SC insulin
1 hours after
What is the major complication of DKA
Cerebral Oedema
What bicarbonate levels indicated DKA
<15 mmol/L
What pH levels indicated DKA
Less tahn 7.3
Once plasma levels fall below 11.1 mmol/L, what should be done
Add 5% dextrose alongside IV fluids + correct Hypokalaemia
Should SC insulin be started before or after starting IV fluids in DKA
After
What serum levels hsould be monitored hourly in a DKA
Glucose, ketones and ECG
What should be added to the fluid if k+ ions are below 5.5mmol/L
K+
After the initial hour treatment with saline, how frequently should fluid be given in a DKA
1L 0.9% saline + 40mmol KCL, followed by another - 2L in total at 2 hours
Then again at 4 hours
Then again at 6 hours
By how much should serum ketone levels drop by per hour
0.5mmol/L/hour
If insulin rate is not achieved when managing a DKA, what should be done
Catherisation
If capillary glucose falls below 14 mmol/L, what hosul dbe done
125ml/hr 10% glucose alongside saline
insulin be stopped at what blood ketone level
<0.3 mmol AND pH>7,3 AND HCO3- >18mmol/L
What endocrinological condition can cause galactorrheoa in men
Hypothyroidism and Liver disease
Name three germ cell tumours that can cause gynecomastia
Sertoli Cell
Leydig Cell
Germ cell
What endocrinological condition causes gynecomastia
Hyperthyroidism
Name two medications that can cause gynecomastia
Spironolactone
Ketoconazole
Other than PCOS, name three endocrinological causes for hirsutism
CAH
Cushing’s
Acromegaly
Insulin Resistance
Name two medications that cause hirsutism
Steroids
Phenytoin
What is Conn’s Syndrome
Adrenal Adenomas
Name some features of hyperaldosteronism
Polyuria
Polydipsia
Lethargy
Hypertension
What metabolic disturbances are seen on blood tests in hyperaldosteronism
Metabolic alkalosis
Hypokalaemia
What medication can be given to assist hyperaldosteronism
Spironolactone or Eplenernone
What causes secondary hyperparathyroidism
Increased secretion of PTH by parathyroid glands IN RESPONSE to low calcium ions caused by kidney, liver or bowel disease
What is tertiary hyperparathyroidism
Autonomous secretion of PTH due to CKD
Name some causes of secondary hyperparatyhyroidism
Vit D deficiency
Pancreatitis
Rhabdomyolysis
Hungry bone syndrome
Calcium malabsorption
CKD
Pseudohypothyroidism
Describe Calcium, phosphate, PTH and ALP levels in Vit D deficiency
SECONDARY Hyperparathyroidism:
Calcium - Normal
Phosphate - Low
PTH - High
ALP - High
Describe Calcium, phosphate, PTH and ALP levels in CKD
Calcium - High
Phosphate - High
PTH - High
ALP - High
Describe Calcium, phosphate, PTH and ALP levels in Malabsorption
Calcium - Low
Phosphate - Low
PTH - High
ALP - Normal
Describe Calcium, phosphate, PTH and ALP levels in Pseudohypoparathyroidism
Calcium - Low
Phosphate - High
PTH - High
ALP - Normal/High
What results in tertiary hyperparathyroidism
Prolongued secondary hyperparathyroidism
What is tertiary hyperparathyroidism
Glands produce excessive PTH even after the hypocalcaemia is corrected
Usually caused by CKD
Management of hyperparathyroidism
Cincalcet (mimics action of calclium on tissues)
Total or partial parathyoridectomy
What is calcium ions floating in th eblood bound to
Calcium Oxalate
What are non diffusible calcium ions bound to
Albumin (calclium not needed for cellular processes)
What is active vitamin D called and where is it activated
1,25 Dihydroxy Vit D
Two actions of PTH
Stimulates breakdown of bone
Kidneys stop excreting calcium + get rid of phosphate ions