Miscellaneous- Endo Flashcards
Causes of hypoglycaemia
Diabetics- excess insulin or se of sulfonylureas
Non-diabetics- EXPLAIN (exogenous drugs, pitiatary insufficiency, liver disease, addisons, insulinoma, non-pancreatic neoplasm)
What is HHS
Hyperosmolar hyperglycaemia is a medical condition resulting in marked hyperglycaemia, hyperosmolality and mild/no ketosis
What is the tx for HHS
1) normalise osmolality
2) Fluid replacement
3) slow infusion of insulin
4) correct potassium if required and give lmwh
What are the lab values for DKA (glucose, ph, bicarbonate and ketones)
Glucose >11.1
Ph<7.3
Bicarbonate<15mmol
Ketones >3mmol
What is the treatment for DKA
1) fluid replacement IV 0.9% saline
2) intravenous infusion of insulin (administer slowly, 18-25 risk of cerebral oedema0
3) correction of electrolytes
4) long insulin should be continue, short insulin should be stopped
Causes of hyperglycaemia
Withdrawal/reduced insulin utilisation
Increase glucose production
Secondary to pancreatitis, Cushing/acromegaly, use of gloucocorticoids
Complication of diabetes
Micro vascular- nephropathy, neuropathy, retinopathy
Macrovascular- mi, stroke, pvd (gangrene)
What is a prolactinoma
Benign lactrophs adenoma secreting prolactin
What inhibits the production of prolactin
Dopamine
Sx of prolactinomas
Oligomenorrhaea/ammenorrhoea Loss of libido Erectile dysfunction Galactorrhoea Infertility Osteoporosis Opthamaloplegia Headaches decrease facial hair Weight gain
Tx for prolactinoma
1st line- dopamine agonist- cabergoline or bromocriptine
2nd line- transpenoidal surgery
Secretion of GH from anterior pituitary acts on the liver. What does the liver secrete in response to this
IGF-1
What are the sx of acromegaly
Large forehead- frontal bossing Large nose Large hands and feet Large protruding jaw Large tongue Arthritis from imbalanced growth of joints Skin tags Profuse sweating Headaches Visual lesions
(exams will refer to increase in shoe size or ring size)
What substance can suppress GH
High levels of glucose
What are the ix for acromegaly
1st line- measure serum IGF-1 , Random serum growth hormone
GS- OGTT- Whilst measuring GH, high levels of glucose suppress GH
Tx for acromegaly
1st line- transphenoidal surgery
2nd line- Somatostatin analogues- octreotide
3rd line GH antagonist- pigvisomant
4th line- dopamine agonist- cabergoline or bromocriptine
What substance inhibits GH SECRETION
Somatostatin
What is Cushing syndrome
General term referring to excessive levels of cortisol
What is Cushing disease
Excess glucocorticoids resulting from inappropriate ACTH secretion due to pituitary tumour
What are the causes of Cushing
ACTH Dependant-
Ectopic tumour
Pituitary adenoma
ACTH Independent
Iatrogenic
Adrenal adenoma
List 5 functions of cortisol
1- increase in carbohydrate and protein catabolism
2- increase deposition of fat and glycogen
3- Na retention
4- increase k+ renal loss
5- diminished host responses to infection
Signs and symptoms of Cushing
Purple striae Moon face Buffalo hump Hirsuitism Acne Central obesity Irregular menses/ED Mood changes- depression, lethargy, psychosis Osteoporosis Increase bp HTN Increase glucose Proximal muscle weakness
Gold standard Ix for Cushing and the results presented
1mg dexamethasone
Low cortisol levels= normal
Normal/high cortisol levels= Cushing’s syndrome
8mg dexamethasone Low cortisol- Cushing diseases (pit tumour) Normal/high cortisol- ACTH low- adrenal Cushings ACTH high- ectopic ACTH
Tx for cushings
GS- removal of tumour
Drugs-Metyrapone or ketoconazole (ek flash)
Drug class- Adrenal Steroid Synthesis Inhibitor
What is cranial and nephrogenic diabetes insipidus
Cranial- decreased secretion of ADH
Nephrogenic- insensitivity to ADH
Where is ADH secreted from
Supraoptic nucleus in posterior pituitary
List 5 causes of cranial and nephrogenic DI
Cranial
- CNS infections
- idiopathic
- head trauma
- brain/pituitary surgery
- congenital
- subarachnoid haemorrhage
- autoimmune disorders
Nephrogenic
- electrolyte abnormalities (hyper/hypokalaemia)
- systemic diseases
- medications (lithium, cisplatin, gentamicin)
- CKD
- uropathy
- inherited
What is the serum and urine osmolality in DI
Serum osmolality high
Urine osmolality is low
What is the Ix required in order to diagnose DI and it’s specific type
Gs- water deprivation test (urine osmolality low, serum osmolality high)- diagnoses DI
Desmopressin test- distinguishes which type
Cranial- (low serum osmolality, high urine osmolality)
Nephrogenic- (low urine osmolality, high serum osmolality)
Sx of DI
Polyuria Polydipsia Children may have nocturia No glycosuria Dehydration Sx of hypernatraemia
Tx for cranial and nephrogenic DI
Cranial- give synthetic arginine vasopressin analogue desmopressin (DDAVP)- desmomelt tablets
Nephrogenic- treat the underlying cause
Low sodium diet
What are the three characteristics that are concurrent with SIADH
1- euvolaemia
2- hyponatraemia
3- increase urine na+ (high urine osmolality)
Causes of SIADH
- malignancy- ectopic or pituitary tumour
- drugs- CARDISH (chemotherapy, antidepressants, recreational, diuretics, inhibitors (ssris, ACEI), sulfonylureas, hormones (desmopresssin))
- trauma
- post operative
- neurological- meningitis, encephalitis, SAH
Sx of SIADH
- absence of hyper/hypovolaemia
- n+v
Fatigue
Headaches
Muscle aches and cramps
Hyponatraemia
Ix for SIADH
Diagnosis of exclusion. Short synacthen test to exclude adrenal insufficiency
Serum sodium- low
Urine sodium- high
Tx for SIADH
Acute severe hyponatraemia- IV hypertonic saline solution (3%)
Acute mild hyponatraemia- fluid restriction
Rx- tolvaptan- ADH receptor blocker
What is hypokalaemia
Serum potassium <3.5mmol/l
Causes of hypokalaemia
- increase GI loss (D+V)
- reduced potassium intake- anorexia nervous a, bulimia
- ckd
Increase availability of insulin
Increased potsssium excretion- loop diuretics
Liquorice abuse