Endocrine Flashcards
1st line test for acromegaly
Serum IGF-1 levels are now the first-line test for acromegaly
TFT’s for sick euthyroid?
Normal TSH, low T3, low T4
Low sodium raised potassium =
Addisons
Explain what primary polydipsia is:
Primary polydipsiais when the patient has a normally functioning ADH system but drinks excessive amounts of water, leading to excessive urine production (polyuria). This is notdiabetes insipidus.
Explain what nephrogenic diabetes insipidus is:
Nephrogenic diabetes insipidusis when the collecting ducts of the kidneysdo not respondtoADH. It can beidiopathic, without a clear cause, or it can be caused by:
- Medications, particularlylithium (used inbipolar affective disorder)
- Genetic mutationsin theADH receptor gene(X-linked recessive inheritance)
- Hypercalcaemia(high calcium)
- Hypokalaemia(low potassium)
- Kidney diseases(e.g., polycystic kidney disease)
What is cranial diabetes insipidus?
Cranial diabetes insipidusis when thehypothalamusdoes notproduce ADHfor thepituitary glandto secrete.
Symptoms of diabetes insipidus:
- Polyuria(producing more than 3 litres of urine per day)
- Polydipsia(excessive thirst)
- Dehydration
- Postural hypotension
What do investigations for diabetes insipidus show?
- Low urine osmolality(lots of water diluting the urine)
- High/normal serum osmolality(water loss may be balanced by increased intake)
- More than 3 litreson a 24-hour urine collection
Thewater deprivation testis the test of choice for diagnosingdiabetes insipidus.
Management of cranial diabetes insipidus:
The underlying cause should be treated. Mild cases may be managed conservatively.
Desmopressin(synthetic ADH) can be used incranial diabetes insipidusto replace the absent antidiuretic hormone. The serum sodium needs to be monitored, as there is a risk ofhyponatraemia(low sodium) with desmopressin.
Management of nephrogenic diabetes insipidus:
The underlying cause should be treated (e.g., stopping lithium). Mild cases may be managed conservatively.
Nephrogenic diabetes insipidusis less straightforward to treat. Management options include:
- Ensuring access to plenty of water
- High-dose desmopressin
- Thiazide diuretics
- NSAIDs
What drugs can cause type 2 diabetes?
- Steroids
- Atypical neuroleptics
- Thiazides
- Beta-blockers
Endocrine causes of type 2 diabetes:
- Cushing’s syndrome/disease
- Acromegaly
- Pheochromocytoma
- Thyrotoxicosis
How is type 2 diabetes diagnosed?
If symptomatic one of the following results is sufficient:
- Random blood glucose=11.1mmol/l
- Fasting plasma glucose=7mmol/l
- 2 hour glucose tolerance=11.1mmol/l
- HbA1C=48mmol/mol (6.5%)
If the patient is asymptomatictworesults are required from different days.
What to do if metformin is not tolerated due to GI side effects?
Switch to modified release metformin.
When should SGLT-2 inhibitors be used?
- QRISK >10%
- Established CVD
- Chronic HF
