Endocrine System Flashcards
what is diabetes insipidus?
where large amount of dilute urine are produced which causes extreme thirst
what are the 2 types of diabetes insipudus
- cranial = vasopressin or desmopressin - the hypothalamus does not make enough ADH
- Nephrogenic = thiazide diuretics; paradoxical - the kidneys do not resppond to ADH
what is desmopressin?
a more potent analouge of vasopressin with a longer duration of action and no vasoconstrictior effects
in what 2 conditions is desmopression used?
diabetes insipidus
nocturnal enuresis
what’s the main SE of desmopressin?
hyponatraemic convulsions
what electrolyte disbalance does inappropriate secretion of ADH cause?
hypOnatraemia
fluid restriction is used to correct hypOnatraemia - what drugs could you use if fluid restriction doesn’t work?
demeclocycline - blocks renal tubular effect of ADH
tolvaptan - vasopressin antagonist
what effects can rapid correction of hypOnatraemia cause?
osmotic demyelination of neurons, serious CNS effects - must correct slowly
what does high mineralocorticoid activty do to fluid?
causes fluid retention
what mineralocorticoid is the most potent and retaines the most fluid?
In what condition would this be beneficial?
fludrocortisone is the most potent
fluid rentention is beneficial in someone who is hypotensive e.g., adrenal insuffiency due to septic shock
How do mineralocorticoids affect electrolytes?
what ones have the most profound effects and what ones have a negligible effect?
Na+ and water retention = HTN
K+ and Ca2+ loss
most profound effect with fludrocortisone
significant effect with hydrocortisone, corticotrophin, tetracosacitide
negligible with beclometasone and dexamethasone
Besides fluid retention, what activity does high glucocorticoid have?
What glucocorticoids are most potent and used if fluid retention is a disadvantage
anti-inflammatory
most potent = dexamethasone/betamethasone
what are the side effects of glucocorticoids? ACHING BOSOM
- Musculoskeletal (osteoporosis, muscle wasting)
- Gastro-intestinal (peptic ulcers, dyspepsia) - cousel to take with ot after food
A - drenal suppression
C- ushing’s syndrome with high doses
H - yperglycaemia - diabetes
I - infections (immunospuuression), insomnia
N - ervous system; psychiatric reactions
G - laucoma, GI ulcers
B - lood pressure increase (HTN)
O - steoporosis
S - skin thinning
O - besity
M - uscle wasting
what’s the MHRA advice regarding methylprednisolone injectable medicine containing lactose?
do not use in patients with cow’s milk allergy - serious allergic reactions such as bronchospasam and anaphlyaxis reported
what are 6 key corticosteorid counselling points?
- risk of infection
- adrenal suppression - carry steroid card
- psychiatric reactions
- withdrawal of corticosteorids
- need for GI protection
- taking am to mimic body’s natural cortisol produciton and prevent insomnia
in what scenarios shoulds you avoid abrupy withdrawal of corticosteroids?
- long erm use >3weeks
- > 40mg prednisolone daily or equivalent for more than 1 week
- repeated doses taken in the evening
- recent repeated courses
- short course within 1-yr of stopping long ter, steroids
- have other causes of adrenal suppression
when do you need to give someone a steroid card?
taking long term steroids for more then 3 weeks
consider for patients using greater than maximum licensed doses of inhaled corticosteroids
are corticosteroids safe in pregnancy and breastfeeding?
what should be monitored?
generally safe - monitor fluid retention in pregnant women
what is hypopituitarism?
pituitary gland does not stimulate hormone secretion by target glands
what steroid replacement do you give in someone with hypopituitarism?
how is this different to the replacement given for adrenalectomy and Addison’s disease?
Hypopituitarism - replace with hydrocortisone NOT fludrocortisone (renin-angiotensin system will regular aldosterone) so just need to replace cortisol and other hormones e.g., sex. thyroid
Adrenalectomy/Addison’s:
Have both low cortisol and aldosterone so need to replace with hydrocortisone and fludrocortisone
What is Cushing’s syndrome characterised by?
Name some symptoms
hypercortisolism (high cortisol)
Symptoms = skin thinning, moon face, acne, buffalo hump, striae (stretch marks)
what are the 2 drugs to treat for Cushing’s syndrome? What’s the safety advice and patient counselling with both options?
- Ketoconazole
Safety advice = life-threatening hepatotoxicity
Counselling = signs of liver toxicity (fatigue, anorexia, N&V, jaundice, dark urine, itching
counselling = adrenal insufficiency as - Cortisol-inhibiting drugs (Metyrapone)
Safety advice = adrenal insufficieny
Counselling = hypotension, hyponatraemia, hyperkalaemia, hypoglycaemia
what is diabetes mellitus characterised by and what are the two types?
characterised by hyperglycaemia
Type 1 = insulin deficiency: pancreatic beta cells destroyed causing insufficient insulin
Type 2 = insulin resistance: reduced insulin secretion/peripheral resistance to insulin
when should you start screening for long term complications in diabetes?
after 12 years old or 5 years after diagnosis
is a statin given to all diabetes as primary prevention?
no:
given to all type 1 diabetes and only type 2 who have CV risk score >10%
what’s one way to protect vision in diabetes?
by treating hypertension to protect visual acuity
what is used to help protect kidneys in nephropathy?
what can this do to hypoglycaemic effects of drugs and insulin?
ACEi/ARB
can potentiate hypoglycaemia effect
what drugs can be used to manage painful neuropathy?
analgesics: strong opiods = oxycodone/morphine (specialist use)
Duloxetine, tricyclic antidepressants: amitriptyline, nortrityline
anti-epileptics: gabapentin, pregabalin, carbamazepine
what are the effects of autonomic neuropathy and what drugs can be used to manage them?
diabetic diarrohea: codeine or tetracycline
gastroparesis: erythromycin
Erectile dysfunction: sildenafil
what are the effects of gustatory neuropathy and what can be used to manage them?
sweating face, scalp, head, and neck: antimuscarinic/antiperspirant
what can be used to manage neuropathic postural hypotension in diabetes?
fludrocortisone and increased salt intake
in pregnancy, when would insulin requirements increase?
in 2nd and 3rd trimester
in people with pre-existing diabetes planning to get pregnant, what HbA1c should you aim for and what drug should you give?
what is the purpose behind this?
HbA1c - 48mmol/l
5mg folic acid (diabetes is high risk group for neural tube defects)
do these things to reduce the risk of congenital malformations
how should you manage a pregnant lady’s insulin?
what’s the first choice?
another option?
what to do in post natal period?
- longer acting first choice (Isophane): may be appropriate to continue using long-acting analouges: glargine or detemir if good glycaemic control before pregnant
- option: continuous subcutaneous infusion pump: women with difficulty achieving glycaemia control with multiple daily injections without significant disabling hypoglycaemia
- reduce insulin immediately after birth due to increased risk of hypoglycaemia, need to monitor blood glucose to determine dose
what should you in monitor in pregnant women taking corticosteorids?
fluid retention
during pregnancy in people with pre-existing diabetes treated with insulin - how should you counsel them in terms of glucose control?
- explain hypoglycaemic risk in all pregnant women treated with insulin (especially in 1st trimester)
- carry fast acting form og glucose
- for type 1, pescribe glucagon if needed
how would you manage a pregnant patients T2DM medication who is not on insulin?
stop all oral antidiabetic drugs except metformin, substitute with insulin
how should you manage medicines in a pregnant patient with T2DM who is breast feeding?
continue metformin or resume glbenclamide post birth
how do you manage gestational diabetes in someone with glucose <7 mmol/l at diagnosis?
1st line = dietary and exercise advice
2nd line - metformin if blood glucose target not met in 1 - 2 weeks OR insulin (can be added if metformin not effective alone)
how do you manage gestational diabetes in someone with glucose >7 mmol/l at diagnosis?
1st line - insulin, with or without metformin + dietary and exercise measures
how do you manage gestational diabetes in someone with glucose 6 - 6.9mmol/l at diagnosis with hydroaminos (too much amniotic fluids) or macrosomia (big baby)?
1st line = insulin with or without metformin
is DKA more common in T1D or T2D?
what are some of the signs?
type 1
signs = severe hyperglycaemia, high blood ketones, ketonuria, pear drop breath, dehydration, drowsiness