Endocrine Flashcards
What is the relevance of oestrogen therapy when assessing thyroid fxn?
Oestrogen causes raised thyroxine binding globulin in the serum –> total serum thyroxine may be misleading
In that situation measure serum free thyroxine
Unifying diagnosis for a pt presenting with DM, deranged LFTs and hypogonadotropic hypogonadism? Initial screening test?
Haemochromotosis
Genetic analysis for C282Y and H63D mutations (will pick up 90% of cases in Europeans) or Serum ferritin
10% of patients with PCOS will also have increased prolactin. What is mechanism of this?
Unknown
Note: does not suppress oestradiol and LH/FSH like a prolactinoma. PCOS increased LH and normal/low FSH
FSH/LH findings in PCOS
PCOS increased LH and normal/low FSH
Treatment of familial hypocalciuric hypercalcaemia
None needed
In managing DM what is the pre breakfast glucose goal?
4-7
Note: if need to increase insulin generally it is increased in 10% increments
In a patient with congenital adrenal hyperplasia who requires stress dosing of there steroids the glucocorticoid is increased but the mineralocorticoid is not T/F
T
Stoping amiodarone is the management for amiodarone induced thyrotoxicosis T/F
F - stop amiodarone (if possible) and treat with steroids
What type of vision loss with craniopharygioma
inferior bitemporal hemianopia
Note: pit tumor typically causes superior bitemporal hemianopia
If free T4 and T3 are high, but TSH is normal or high, what is the next step in investigation
Pituitary MRI
Note: to look for a pituitary mass (TSH-secreting adenoma)
What is Nelson’s syndrome
Enlargement of an ACTH-producing tumour in the pituitary gland, following surgical removal of both adrenal glands in a patient with Cushing’s disease.
What testosterone and FSH/LH pattern would be expected in a male with primary vs secondary hypogonadism
In both decreased testosterone and sperm count
Primary: problem with testes –> increased FSH/LH as they try to stimulate the testes
Secondary: problem with either hypothalamus or pituitary gland –> decreased or inappropriately normal FSH/LH
In a pregnant pt with hyperthryoidism what is the treatment
1st trimester: PTU
2nd trimester: carbimazole
DeQuervain’s thyroiditis typical presentation
Tender goitre, weight loss and general malaise.
A markedly raised ESR (>50 and usually 100) is typical.
Initially hyperthryoid and then become hypothyroid
What is the relevance of sick euthyroidism being associated with hypoadrenalism
Hypoadrenalism which is either primary or secondary, the addition of thyroxine can precipitate acute hypoadrenalism
Insulin antibodies are found almost exclusively in which patient cohort?
Young children with type 1 diabetes.
What TFT pattern would be expected in over replacement with thyroxine?
Increased T3/T4
Suppressed TSH
3 criteria needed to define the resolution of DKA
pH >7.3
ketones <0.3 mmol/L
patient is able to eat and drink
When is K replacement needed in DKA mgmt
K up to 5.5mmol/L
Note: 3.5 - 5.5 give 40mmol in IVF L; < 3.5 seek specilaist advice for how much to give
Which investigation most likely to differentiate between Amiodarone induced thyrotoxicosis (AIT) type 1 and type 2?
Colour flow Doppler
NB: appears to be superior to IL-6
Which diabetes drugs increase levels of PTH, drive an increase in bone turnover, and are associated with increased risk of bone fracture.
SGLT-2 inhibitors
such as canagliflozin
Most authorities recommended that metformin should be stopped in patients with a creatinine above ___
150
Note: This is not universal policy and many patients continue on metformin with creatinines much higher than 150 without any ill effect.
Which MEN is associated with mutation in RET
MEN2
Note: MEN1 and 2 are both autosomal dominant
Which MEN is associated with MENIN?
MEN1
Which MEN2 has a worse prognosis?
MEN2B - this is because the medullary thyroid Ca is usually more aggressive.
Note: death in mid twenties can commonly occur in its who present with clinical signs of medullary thyroid Ca
What is the most common type of thyroid Ca?
Papillary ( 80-85)
Note: then follicular (5-10%); rare medullary and anaplastic
What is the typical presentation of thyroid Ca?
Single nodule and otherwise asymptomatic
Presents in 30s or 70s usually
Note: TFTs are normal
Which type of thyroid Ca has worse prognosis?
Anaplastic
Which type of thyroid Ca is more common in areas with low iodine?
Follicular
Which type of thyroid Ca is more common in areas with high rates of thyroiditis?
Thyroid lymphoma
T2 DM is association what that islet pathology
Islet amyloid deposition
Most common antibodies in Hashimotos
Anti TPO
Note: aka anti microsomal antibodies
Typically when reducing insulin go in increments of ___%
20%
In a patient with T2DM and Hba1c significantly below 75 mmol/mol what is the insulin of choice to start?
Humane isophane insulin (also referred to as a Neutral Protamine Hagedorn [NPH] insulin) is the first-line recommended insulin to use in a type 2 diabetic. These are intermediate acting insulins usually used once daily at night or twice a day.
Note:
A long-acting insulin analogue might be useful in someone who struggles to inject a twice a day NPH insulin to reduce the frequency of injections to once a day (e.g. someone who requires assistance to inject from a carer or district nurse).
A biphasic ‘mixed’ preparation is recommended if an individual’s diabetic control is especially poor (HbA1c > 75 mmol/mol).
Tx of papillary thyroid carcinoma
Thyroidectomy AND radioiodine-131 therapy
Colonoscopy recommendations for pts with acromegaly?
Start at 40 yrs due to high risk colon Ca
If elevated IGF1 or adenomas found: repeat in 3 yrs
If not: repeat in 5 years
In the setting of diabetes and stable renal function what test is considered the most appropriate test to detect and quantify proteinuria.
Albumin:creatinine ratio
The presence of breast development in the absence of secondary sexual hair, with a history of hernias as a child is suggestive of a diagnosis of ____
Androgen insensitivity syndrome
Drugs that interfere with thyroxine absorption?
Binding agents ( cholestyramine and sevelamer)
iron sulphate
proton pump inhibitors
Relevance of undetectable thyroglobulin on TFTs
Clinches the diagnosis of factitious hyperthyroidism.
Note: thyroglobulin is the precursor of thyroid hormones, therefore if undetectable, indicates an external source of thyroid hormone has been administered.
Goal BS in insulin dependent DM
Pre meal: 4-7
Pre bed: 6-8
1st line tx of thyroid eye disease?
Steroids
Compare Turners to Kallmans?
Both have decreased oestrogen but
Turners is a hypergonadatrophic hypogonadism (increased FSH/LH)
Kallmans hypogonadatrophic hypogonadism (normal/decreased FSH/LH). It is also assoc with central defects (eg cleft lip), colour blindness, and deafness.
Pseudohypoparathyroidism is associated with ____
Short stature and shortening of the fifth metacarpal
_____ is the best investigation for confirming subacute thyroiditis
Radioactive iodine uptake scan
Note: aka De Quervains. It is due to increased release of stored thyroid hormone rather than increased production therefore no role for PTU/carbimazole. Can treat symptoms with propranolol
Metformin is known to cause what nutritional deficiency?
B12
Tx of myxoedema coma?
IV T3 and hydrocortisone
Note: can treat clinically even before lab results
