Endocrinological Conditions Flashcards
Addison’s disease (pathophysiology, trigger, hallmark signs, presentation, diagnosis, adrenal crisis - symptoms and management, monitoring)
Pathophysiology: Insufficient production of glucocorticoids and mineralocorticoids (+/- androgen). Both adrenal glands
are affected.
Trigger: autoimmune-related (usually); others include infection, metastatic cancer and some drugs.
Hallmark signs: fatigue, anorexia and weight loss, postural hypotension, and skin and mucosal hyperpigmentation.
May be accompanied by hyperkalaemia and hyponatraemia.
Presentation:
● Dehydration, hypotension, orthostasis
● Absence of axillary and pubic hair and decreased body hair (female)
● Increased pigmentation of skin and mucous membranes +/- areas of vitiligo (long-standing)
Diagnosis: confirmed by combination of
● Positive short Synacthen test (30 and 60 mins after injection)
● Elevated ACTH
● Elevated plasma renin
Adrenal crisis: triggered by illness or surgery resulting in acute cortisol deficiency. EMERGENCY
● Signs and symptoms: Nausea, vomiting, diarrhoea, hypoglycaemia and hypercalcaemia
● Treatment: Start treatment ASAP - do not wait for lab results
○ Hydrocortisone 100 mg IV STAT or prednisolone 40 mg PO
○ Start fluid resuscitation with sodium chloride 0.9%
○ Inform endocrinology team
Monitoring:
● Annual review once stable
● Pathology (serum sodium, potassium and plasma renin concentrations)
● Ask about:
○ Glucocorticoid excess e.g. weight gain, peripheral oedema, bone mineral density (** assess every
2 years), hyperglycaemia
○ Glucocorticoid deficiency e.g. LOA, progressive skin pigmentation, lethargy
○ Mineralocorticoid excess e.g. HTN
○ Mineralocorticoid deficiency e.g. postural hypotension, tachycardia, hyperkalaemia
● Treatment: aim for upper-normal reference of plasma renin concentration
42
● Prevention: higher chance of other autoimmune disease. Counsel patients for signs and symptoms of
coeliac, thyroid, T1DM. Screen with pathology after 1 year and then 5 yearly.
● Patient education for self-care:
○ Increase glucocorticoid dose during intercurrent illness
○ Recognise early features of adrenal crisis
○ Carry injectable hydrocortisone when away from medical care
○ Wear an alert bracelet or necklace
○ Carry a wallet card with detail about condition and treatment
Carcinoid syndrome (clinical features, potential locations, Ix)
Clinical features:
● Classic triad - skin flushing (face), diarrhoea (with abdominal cramp), valvular heart disease
● Other - wheezing, telangiectasia, hypotension, cyanosis
Potential locations: appendix/ileum, stomach, bronchi
Investigations: 24 hour urinary excretion of 5-HIAA
Cushing’s syndrome ( Hx and Ex, when to test, Ix)
History and examination suggestive of Cushing’s: decreased libido, obesity/weight gain, plethora, round face, menstrual changes, hirsutism, HTN, ecchymoses, lethargy, dorsal fat pad, impaired glucose tolerance)
When to consider testing:
● Unusual findings for age (osteoporosis or hypertension in young adults)
● Multiple progressive features of Cushing’s (facial plethora, proximal myopathy, striae and easy bruising)
● Adrenal incidentalomas
Investigations: Low suspicion = 1 test, high suspicion = 2 tests
● Late-night salivary cortisol (two measurements)
● 24 hour urinary free cortisol excretion (two measurements)
● Overnight 1mg dexamethasone suppression test
Diabetes - Type 1 (presentation, investigations)
Key point
● Mostly in children but can occur in adults
Suspicion if:
● Ketosis/ketonuria
● Polyuria
● Acute weight loss (>5% in 1 month)
● < 50 years of age
● Family history of autoimmune disease
● Acute onset
Managing if suspicion:
● Assess ketone level and treat hyperglycaemia (seek help immediately if ketone >1.5)
● Confirmatory test
○ IAA, ICA, GAD (present in 90% of cases)
○ C-peptide (<0.2 on non-fasting samples)
Diabetes - type 2 (screening)
Yearly
- Aboriginal and Torres Strait Islander from 18 years
- Individuals with impaired glucose tolerance test or
fasting glucose
3 yearly
- AUSDRISK (from 40 years) >=12
- Previous CVD
- History of gestational diabetes
- PCOS
- Antipsychotic drugs
Diabetes - type 2 (diagnosis)
Symptomatic
One of the following:
● Patient presenting with hyperglycaemic crisis
● Single elevated BSL (fasting) >=7
● Single HbA1c >= 6.5%
● BGL (random) >=11.1
** Second test not required unless diagnostic uncertainty remains
Asymptomatic
● HbA1c >=6.5% on two separate occasions
○ May not be elevated in early diagnosis, does not exclude is there is elevated blood glucose
● BSL (fasting) >=7 or BSL (random) >=11.1 on two separate occasions
T2DM medications - metformin
MOA: reduces glucose production in the liver and reduces insulin requirements.
Immediate:
● Up to 2g, divided doses
Modified:
● Up to 2g daily
ADRs: GI effects, B12 deficiency, lactic acidosis (rare)
Contraindicated: eGFR <30
T2DM medications - sulphonylurea (e.g. gliclazide)
MOA: increase insulin secretion via the pancreatic sulfonylurea receptor
ADRs: weight gain, hypoglycaemia
Caution:
● Avoid glibenclamide and glimepiride in kidney impairment
● Reduce dose of gliclazide and glipizide if CrCl <30
T2DM medications - DPP-4i (-gliptin)
MOA: increase endogenous concentrations of incretin hormone that are produced in
the gut
Example: linagliptin 5 mg orally daily
Caution: Adding DPP-4i to GLP-1 does not improve glycaemic control. Reduce dose in
CKD (except linagliptin).
ADRs: pancreatitis (rare), MSK pain.
Contraindication: previous pancreatitis, heart failure.
T2DM medications - GLP-1 RA (-tide)
MOA: increase insulin secretion and delay gastric emptying
Example: exenatide MR 2mg subcut weekly
ADRs: nausea (improves over time), pancreatitis (rare)
Contraindications: pancreatitis (acute or history), Fhx thyroid cancer or endocrine
neoplasia, CrCl <30 (liraglutide CrCl <15)
T2DM medications - SGLT2-i (-flozin)
MOA: inhibit reabsorption of glucose from proximal convoluted tubule of kidney
Example: empagliflozin 10mg orally daily (max 25mg)
Caution: avoid in patients with low-carb diet, not effective in patients with impaired
kidney function, be mindful of patients on frusemide.
Advantages: reduces secondary CVD including mortality
ADRs: UTI, reversible increase in creatinine
Contraindication: CrCl =<45
T2DM medications - insulin
MOA: supplement endogenous insulin production Strategies: ● Basal insulin ● Once-daily fixed-dose combination ● Twice-daily fixed-dose combination Strategy for commencement: Start with once-daily basal insulin, uptitrate by 2-4 units every 3-7 days ADRs: hypoglycaemia, weight gain
Combination
● Metformin should be continued for as long as possible
● Caution of sulfonylurea due to risk of hypoglycaemia.. Should cease when on
BD insulin.
● GLP-1 effective with basal insulin (minimise hypoglycaemia and weight gain)
● DPP-4i should be temporarily ceased when starting basal insulin
● SGLT2 can reduce weight gain
T2DM medication considerations - CVD
Sulfonylurea: Increased risk when used alone (gliclazide, glimepiride) but neutral when
used in combination with metformin
SGLT2i and GLP-1 RA have selective benefit
** Saxagliptin (DPP-4i) has increased hospitalisation rate for heart failure
T2DM medication considerations - hypoglycaemia
Sulfonylurea:
● Gliclazide has fewer hypoglycaemic episodes compared to others
● Glibenclamide has the highest risk especially in older people
T2DM medication considerations - GI symptoms
Worse with:
Metformin
GLP-1 RA (trulicity, exenatide)
T2DM medication considerations - weight
Sulfonylurea:
● Gliclazide has neutral effect
● Others have modest weight gain
SGLT2i and GLP-1 RA have moderate weight loss
T2DM medication considerations - renal impairment
Metformin ● Reduce dose by 50% if eGFR 30-60, cease if CrC <30 Sulfonylurea ● Cease if CrC <15 DPP-4i ● Can be used in all stages with nil dose reduction SGLT2i ● Cease if eGFR =<45 GLP-1 RA ● Cease if eGFR < 30 ● Dulaglutide <15
T2DM and HTN
Automatically high risk for CVD
Aim BP 130/80
T2DM and CVD
Automatically high risk
Manage cholesterol and BP
SGLT2 recommended (decreased CVD events and risk of hospitalisation for heart failure) ● Empagliflozin 10mg daily with food
