Endocrinology Flashcards
what are the blood results for Addison’s?
Hyponatraemia
Hyperkalamiae
hypoglycaemia
metabolic acidosis
how do we manage type 2 DM?
first start lifestyle changes
if HbA1C rises to 48 on lifestyle advice, add Metformin
if HbA1C rises add a second medication from the following:
- Gliptin (DDP4 inhibitor)
- sulfonylurea
- SGLT-2 inhbitor
- pioglitazone
if, despite the 2nd med, HbA1C rises to/or remains above 58mmol/mol - add a 3rd med
triple therapy with any of the following combinations:
- metformin + sulfonylurea + pioglitazone
- metformin + sulfonylurea + SGLT-2 inhibitor
- metformin + sulfonylurea + gliptin
- metformin + pioglitazone + SGLT-2 inhibitor
or consider insulin therapy
finally, if triple therapy not working
a GLP-1 analogue can be tried in combination with metformin and a sulfonylurea if BMI>35 with obesity related problems or <35 but cant take insulin
how do we manage idiopathic adrenal hyperplasia?
aldosterone antagonists e.g. spironolactone
what are the targets in DKA treatment?
reduce ketones by 0.5 mmol/L/h
reduce glucose by 3 mmol/L/h
increase bicarb by 3 mmol/L/h
maintain potassium between 4-5.5mmol/L
what are side effects of pioglitazone?
weight gain, osteoporosis, swelling of legs/ankles, risk of liver disease, anaemia risk, fluid retention
contraindicated in previous bladder cancer patients
what usually precipitates HHS (hyperglycaemic, hyperosmolar state)?
infection, MI, stroke or other acute illness
how do DDP4 inhibitors/gliptins work?
give names of drugs
DDP-4 enzymes are involved in deactivating incretins (GLP-1). by inhibiting them - we raise the levels of GLP-1 which bind to Beta cells and increase insulin production and secretion.
e.g. sitagliptin, vildagliptin, linagliptin
how does the BD (biphasic) insulin regime work?
patient takes 2 premixed insulin doses - via disposable pens
good for a regular lifestyle
twice‑daily insulin detemir is the regime of choice.
what are the causes behind primary hyperparathyroidism?
usually - adenoma (80% cases) multifocal disease (10-15%) carcinoma (<1%)
what are side effects of sulfonylureas?
weight gain, hypoglycaemia, upset stomach, skin rash/itching
what are 3 features of Hashimoto’s thyroiditis?
hypothyroidism
goitre
anti-TPO
which thyroid cancer secretes calcitonin?
medullary cancer
when do we treat subclinical hypothyroidism?
if TSH is btwn 4-10
for <65s with symptoms - treat with a trial of levothyroxine and continue if shows improvement
if asymptomatic or older - watch and wait, repeat TFTS in 6 months
if TSH is >10
for <70s - treat with levothyroxine
watch and wait for older patients
at what HbA1C level do we add a second drug to metformin for T2DM patients?
58
what is involved in the HPA axis?
Hypothalamus secretes corticotropin releasing factor (CRF)
CRF stimulates the anterior pituitary to secrete ACTH
ACTH stimulate the adrenal cortex to secrete cortisol and androgens
which is the insulin regime of choice for adults?
multiple daily basal-bolus injections
which drugs can cause hypercalcaemia?
thiazide diuretics
calcium containing antacids
what is an important complication of fluid resuscitation in young DKA patients?
cerebral oedema
whats the most common cause of Addison’s worldwide?
Tb
tell me about ultra fast acting insulin
examples = novorapid, humalog
used to inject before a meal or just after. helps to match insulin to what is actually eaten
when do we consider transferring a DKA patient to ICU?
if there are signs of severe DKA: pH < 7 bicarb < 5 blood ketones > 7 GCS < 12 K+ < 3.5 oxygen sats <92% low BP or pulse
how do you classify BMI into normal/overweight/obese?
normal= 18.5 - 25 overweight =25-30 obese 1 =30-35 obese 2 =35-40 obese 3 =>40
what is the MoA of carbimazole?
it blocks thyroid perioxidase from iodinating the tyrosine residues on the thyroglublin - this reduces the production of thyroid hormones
what are side effects of Gliptins?
usually well tolerated
can cause hypoglycaemia, hives, fluid retention, UTI, headaches, facial swelling nasopharyngitis
how do we manage pregnancy in diabetic patients?
in advance, have a target of 48mmol/mol!
take folic acid 5mg OD
during pregnancy, have a blood glucose control assessment every 1-2 weeks throughout pregnancy
what are the TFT levels in subclinical hypothyroidism?
elevated TSH with normal T4
what is the single most useful test in determining the cause of hypocalcemia?
parathyroid hormone
which are the 2 most common thyroid cancers?
papillary (70%)
follicular (20%)
what are symptoms of hyperglycaemia?
polyuria polydypsia lethargy genital thrush weight loss visual blurring
what are the clinical features of Paget’s disease?
only 5% are symptomatic
bone pain - lumbar spine, femoral, pelvis
skull bossing, leg bowing
raised ALP, normal phosphate and calcium
skull xray - thickened vault
what is the pathophysiology of secondary hyperparathyroidism?
parathyroid hyperplasia occurs in response to low calcium, almost always in a setting of chronic renal failure
what are the findings in hyperaldosteronism?
raised BP raised/normal sodium low potassium raised bicarbonate (alkalosis) raised aldosterone low renin
which steroid has high GC activity and low MC activity?
dexamethasone and betmethasone
important if we need high anti inflammatory action and low fluid retention e.g. in cranial tumours
why electrolyte deficiency is responsible for sustained hypocalcaemia despite calcium replacement therapy?
magnesium
magnesium is needed for PTH secretion and its action on target tissues
how much potassium should we give to DKA patients?
if potassium is >5.5 give nil
if potassium is 3.5-5.5 give 40mmol/L infusion
if < 3.5 - seek help
what are the symptoms of hyperaldosteronism?
can be asymptomatic
signs of hypokalaemia= cramps, weakness, paraesthesia
High BP and headaches
which hormones are reduced in the stress response?
insulin
oestrogen
testosterone
what are side effects of treatment with levothyroxine?
hyperthyroidism
reduced bone mineral density
worse angina
atrial fibrillation
what is Waterhouse - Friderichsen syndrome?
adrenal failure due to haemorrhage into the adrenal gland, commonly caused by severe infection
severe form of meningococcal sepsis
usually pre-terminal
patients present with sepsis, coagulopathy, extremities cyanosed, comatosed
whats the most important advice to give a patient being started on carbimazole?
if they get any signs of infection they should seek urgent medical review
a rare side effect = agranulocytosis
what’s sick euthyroid syndrome?
its caused by systemic disease
total and free T4 and T3 are minimally low
TSH is normal or slightly low
how do we investigate hyperaldosteronism?
1st line = renin:aldosterone ratio High serum aldosterone low serum renin adrenal vein sampling high resolution CT scan
how do we treat phaeochromocytoma?
surgery is definitive treatment
but we first stabilise the patient with alpha blockers (phenoxybenzamine) and then beta blockers (propanolol)
what is kussmauls breathing?
heavy respiration - expiring CO2 to try and compensate for metablic acidosis
what are the features of LADA?
these patients, although they have autoimmune disease, like type 1 DM, are picked up later in life.
their diabetes progresses a lot slower - and may not need insulin in the earlier stages
LADA can often be misdiagnosed at T2 DM but patients are usually younger and less obese
diagnosis may be aided by GAD autoantibody testing or other autoimmune disease
what is Cushing’s disease?
pituitary tumour secreting ACTH causing adrenal hyperplasia
what ABG results are associated with Cushings?
hypokalaemic metabolic alkalosis
give an example of a fluid replacement regime in a DKA patient?
1st hour: 0.9% saline - 1L
2nd hour: 0.9% saline + potassium chloride
what glucose ranges are diagnostic for diabetes?
fasting glucose >7
HbA1C >48
where is ADH secreted from and what does it do?
ADH is released for the posterior pituitary in response to thirst.
ADH causes more aquaporin channels to be inserted into collecting duct membranes in the kidneys. this increases water retention
what are the causes for hyperkalaemia?
AKI drugs - K sparing diuretics, ACE-I, ARBs, spironolactone metabolic acidosis massive blood transfusion addisons rhabdomyolosis
what percentage of pre-diabetic patients progress to type 2/year?
5-10%
how do we treat an adrenal tumour?
for adenoma - adrenalectomy
for carcinoma - radiotherapy and adrenolytic drugs
which mutation is associated with most cases of MODY?
mutation in the HNF1- alpha gene
known as MODY 3
how do we treat hypoparathyroidism?
with alfacalcidol
which is an analogue of vitamin D
what glucose ranges show prediabetes?
42-47 HbA1C
fasting glucose: between 6-7
what do the osteoporosis guidelines recommend regarding a postmenopausal woman who has had a fracture?
give her bisphosphonate and calcium supplements
when do you NOT have to inform the DVLA about taking insulin?
if on temporary insulin for < 3 months
or because of gestational diabetes and wont be continuing the insulin for more than 3 months postpartum
what does thyrotoxicosis alongside a singular hot nodule (on scintography) indicate?
toxic adenoma
this occurs when a single nodule grows on the thyroid gland - producing excess hormones and causing thyrotoxicosis
what are the features of type 2 DM?
associated with lack of exercise, obesity, alcohol and calorie excess
more common in asians, men and elderly
because of excess adipose tissue, there is a relative insulin insufficiency - not enough to go around
which anti diabetic drug increases insulin sensitivity?
pioglitazone
how does diabetes causes damage to the eyes? (2)
1) endothelial changes causes capillary leakage - causing intraretinal oedema which then forms hard exudates. in the macular area this can result in loss of central vision
2) capillary occlusion can cause retinal ischaemia. in the macular area this can cause visual loss. the ischaemia then causes new retinal vessels forming. the new vessels can cause - haemorrhage, fibrosis, etc
all leading to total blindness
how is Addison’s managed?
steroid replacement therapy
hydrocortisone (in 2 or 3 doses per day) and fludrocortisone
what are the features of MEN 1?
3 Ps (parathyroid, pituitary and pancreas) and adrenal and thyroid
whats the most serious potential complication of AKI?
hyperkalaemia
how do we investigate phaeochromocytoma?
24 hour urinary collection of metanephrines
VMA in urine is usually elevated
and serum metanephrines are elevated
what is MEN?
multiple endocrine neoplasia
autosomal dominant disorder
where is prolactin produced?
anterior pituitary gland
what is the pathophysiology of primary hyperaldosteronism?
excess aldosterone leads to Sodium reabsorption, H2O retention and K+ excretion. this leads to raised blood pressure, hypernatraemia, hypokalaemia, and alkalosis
what are side effects to long term steroid use?
endocrine - impaired glucose regulation, hyperlipidaemia, excess hair growth, increased appetite/weight gain
bones - osteoporosis, osteopaenia, avascular necrosis of the femoral head,
immunosuppression
GI - peptic ulceration and pancreatitis
psychiatric - mania, psychosis, insomnia, depression
cushings syndrome - moon face, buffalohump, stria
eyes -glaucoma, cataracts
intracranial hypertension
suppression of growth in children
how do you identify a benign incidental adrenal adenoma?
usually picked up on CT accidentally
the ademona has a rich lipid core with well circumscribed nodules
what are signs of thyrotoxicosis?
tachycardia, maybe irregular pulse, moist warm skin, fine tremors, lid lag/retraction, goitre, thin hair, thyroid nodules/bruit.
how do we manage a prediabetic patient?
encourage to make lifestyle changes - exercise and change diet (more fibre less fat)
consider 500mg OD metformin
test HbA1C regularly - annually
how do we define diabetes?
hyperglycaemia levels sufficient to cause microvascular complications
how often should a T1 DM patient check his blood glucose/day?
at least 4 times a day - before meals and before bed
what are symptoms of hyponatramea?
dizzy, nausea, headache, coma if severe, signs of dehydration or fluid overload
tell me about premixed insulins
e.g. novamix 30
30% SA and 70% LA
which glucose ranges show normal glycaemic control?
HbA1C < 42
fasting glucose < 7
what diabetic medication should we consider as first line for a patient with end-renal failure?
Gliclazide
Metformin is contraindicated (can’t be used in any patient with eGFR < 30)
is a Type 2 diabetic patient, on insulin, allowed to drive a HGV?
yes, but he must meet very strict criteria set out by the DVLA, relating to hypoglycaemia
what are the 2 main causes for hypercalcaemia?
primary hyperparathyroidism
malignancy
these 2 causes account for 90% of cases
what is MODY?
a group of genetic diseases affecting the production of insulin
maturity onset diabetes of the young
usually in those < 25 years
with a strong family history
typically autosomal dominant
number of genes identified
patients usually very sensitive to sulfonylureas
what are the 5 types of thyroid cancer?
papillary follicular medullary anaplastic lymphoma
how is HHS diagnosed?
signs of dehydration
osmolarity: >320mosmol/kg
hyperglycaemic: >30mmol/L with pH>7.3 and no ketonaemia < 3mmol/L
what are the complications of pagets disease?
deafness - CN trapping bone sarcoma skull thickening fractures high output cardiac failure
how would a patient present in phase 1 of subacute thyroiditis ?
tender goitre
hyperthyroidism
raised ESR
globally decreased uptake on iodine scan (Technetium scan)
tell me about long acting/basal insulin?
human insulin analogues
e. g. glargine - used at bedtime, to give a steady insulin baseline all night. good for those who struggle with nocturnal hypoglycaemia
e. g. detemir
what investigation should we do in a patient who’s drowsy, vomiting, dehydrated, abdo pain, polyuria, polydipsia?
CHECK BLOOD GLUCOSE
what does thyroxine interact with??
iron
iron reduces the absorption of thyroxine
take the drugs 2 hours apart
what is the mechanism of action of sitagliptin?
it is a dipeptidyl peptidase 4 inhibitor (DPP-4)
this prevents the breakdown of GLP-1, therefor increasing its levels and so increasing insulin
what rate of insulin should u prescribe for ketoacidotic patients?
0.1 unit/kg/hour
what medication can we use pre-op to decrease cortisol secretion?
metyrapone, ketocanozole, flucanazole
how do patients with hypercalcaemia present?
non specific symptoms
nausea, polydipsia, polyuria, weakness, confusion, constipation
what antibodies are associated with Graves disease?
TSH receptor stimulating antibodies
anti-thyroid peroxidase antibodies
how do we prevent diabetic retinopathy?
primary prevention - BP and glucose control
secondary - regular assessment
immediate anti VEGF treatment in diabetic macular oedema - to prevent new vessels forming e.g. ranibizumb, aflibercept
3) salvage therapy - vitrectomy
whats the best investigation to differentiate between type 1 and type 2 diabetes?
C peptide
this will be low in type 1
(because the pancreas is not producing enough insulin precursor which breaks down to give insulin and C-peptide)
and normal or high in type 2
how does the OD insulin regime work?
once a day, taking a dose of LA insulin
good started for T2 patients switching across to insulin
typical dose is around 1 unit/BMI unit/24 hours
can retain metformin etc if need for tighter control
how do we screen for acromegaly?
by testing serum Insulin-like Growth factor -1 IGF-1, which represents 24 hour GH levels
what are the features of type 1 DM?
usually presents in adolescents/young adults
at risk of ketoacidosis and weight loss
antibody destruction of pancreatic, insulin-producing beta cells (anti bodies include Glutamic acid decarboxylase (GAD) antibodies and islet cell antibodies (ICA)
associated with other autoimmune disease
treated with insulin
what is acromegaly?
excessive GH
in 95% of cases this is secondary to a pituitary adenoma
what is Paget’s disease?
a disease of excessive turnover of the bone - increased osteoclast and osteoblast activity