Endocrinology Flashcards
Prolactinoma - features
Excess prolactin in women:
Amenorrhoea
Infertility
Galactorrhoea
Osteoporosis
Excess prolactin in men:
Impotence
Loss of libido
Galactorrhoea
Management of Prolactinomas
Dopamine Agonists (Bromocriptine/Carbergoline)
Trans-sphenoidal surgery
Treatment for acromegaly (1-4)
- Trans-sphenoidal surgery
- Somatostatin analogue - octreotide
- Pegvisomant - GH receptor antagonist
- Dopamine agonists (Bromocriptine)
Kallman’s syndrome
LH & FSH low-normal
Testosterone is low
Hypogonadotropic hypogonadism
X-linked recessive
Most common drug cause of gynaecomastia
Spironolactone
MEN type I
Pituitary (70%)
Parathyroid (95%)
Pancreas (50%): e.g. insulinoma, gastrinoma
MEN1 gene
MEN type IIa
Medullary thyroid cancer (70%)
Parathyroid (60%)
Phaeochromocytoma
RET oncogene
MEN type IIb
Medullary thyroid cancer
Phaeochromocytoma
Marfanoid body habitus
Neuromas
RET oncogene
Major risks of over-replacement with thyroxine
Osteoporosis
Atrial fibrillation.
ACTH-dependent causes of Cushings
Cushing’s disease (a pituitary adenoma → ACTH secretion)
Ectopic ACTH secretion secondary to a malignancy
ACTH-independent causes of Cushing
Adrenal adenoma
Newly diagnosed adults with type 1 diabetes - 1st line regime
Basal-bolus using twice-daily insulin detemir
Primary hypogonadism
Klinefelter’s syndrome
47, XXY
Hypogonadotrophic hypogonadism
Kallman’s syndrome
X-linked recessive trait
Androgen insensitivity syndrome
X-linked recessive
End-organ resistance to testosterone causing genotypically male children (46XY) to have a female phenotype
Gitelman’s syndrome
normotension
hypokalaemia
hypocalciuria
metabolic alkalosis
Defect in the thiazide-sensitive Na+ Cl- transporter in the distal convoluted tubule.
Subclinical hyperthyroidism
Normal serum free thyroxine and triiodothyronine levels
TSH below normal range (usually < 0.1 mu/l)
(atrial fibrillation) (osteoporosis)
Associated electrolyte abnormalities in Addisons
Hyperkalaemia
Hyponatraemia
Hypoglycaemia
Metabolic acidosis
The ? can be used to distinguish primary adrenal failure from secondary adrenal failure
Long Synacthen test
Phaeochromocytoma - Investigations
24 hr urinary collection of metanephrines
Management of Phaeochromocytoma
Surgery
Alpha-blocker (e.g. phenoxybenzamine), given before a
beta-blocker (e.g. propranolol)
Causes of normal anion gap metabolic acidosis include:
Acetazolamide use
Topiramate use
Renal tubular acidosis type 1 and type 2
Diarrhoea
Type 1 RTA (distal)
Inability to generate acid urine (secrete H+) in distal tubule
Causes hypokalaemia
Nephrocalcinosis and renal stones
Associated with Sjogren’s
Thiazolidinediones
PPAR-gamma receptor agonists
Adverse effects:
Fluid retention - therefore contraindicated in heart failure
Precocious puberty - males
When puberty occurs before 9 in males
21-hydroxylase deficiency
11-beta hydroxylase deficiency
Congenital adrenal hyperplasia
Can cause excess steroid production due to peripheral cause and not central.
SGLT-2 inhibitors
Reversibly inhibit sodium-glucose co-transporter 2 in the PCT to reduce glucose reabsorption and increase urinary glucose excretion
APS type 2
Patients have Addison’s disease plus either:
Type 1 diabetes mellitus
Autoimmune thyroid disease
Adverse effects of Thiazolidinediones
Weight gain
Liver impairment
Fluid retention
Bladder cancer
Patients with T1DM for over 10 years should be considered for?
Statin therapy
Atorvastatin 20mg OD
Thyrotoxic storm - treatment?
Beta blockers
Propylthiouracil
Hydrocortisone
Diabetic gastroparesis - long term management
Domperidone
D2 Receptor Antagonist
Most common cause of Thyroid Cancer
Papillary
Often young females - excellent prognosis
Prolactin secreting macroadenomas secrete very high quantities and PRL level can get how high usually?
> 6000
Treatment of choice for moderately severe active Graves’ ophthalmopathy.
IV methylprednisolone
Medullary thyroid cancer - screening
Calcitonin
Treatment of RTA
Correction of the acidaemia with:
Oral sodium bicarbonate,
Sodium citrate or potassium citrate
Most common cause of Waterhouse-Friderichsen syndrome
Neisseria meningitidis
Rotterdam criteria for the diagnosis of PCOS
Clinical or biochemical evidence of hyperandrogenism
Evidence of oligo- or anovulation
Presence of polycystic ovaries on ultrasound
Serum osmolarity equation
2 * Na+ + glucose + urea
First line treatment in diabetic neuropathy
Amitriptyline
Duloxetine
Gabapentin
Pregabalin
Treatment for Grave’s Disease
Carbimazole
Radioiodine in refractory Grave’s
Causes of Hypokalemia with Hypertension
Liddle Syndrome
Cushing Disease
Conn’s Syndrome
11 Beta Hydroxylase deficiency
Liddle’s syndrome - define
Autosomal dominant
Hypertension and hypokalaemic alkalosis
Disordered sodium channels in the distal tubules leading to increased reabsorption of sodium
Liddle’s syndrome - treatment
Amiloride
Triamterene
Contraindications to Radio-Iodine treatment
Pregnancy
Breastfeeding
Active thyroid eye disease (unless providing steroid cover)
Hypocalcaemia - ECG
Prolonged QTc Interval
Primary hyperaldosteronism
Features?
Hypertension
Hypokalaemia
Metabolic alkalosis
Management of papillary and follicular cancer
Total thyroidectomy
Followed by radioiodine (I-131) to kill residual cells
Yearly thyroglobulin levels to detect early recurrent disease
Management of Hypocalcaemia
Intravenous calcium gluconate
10ml of 10% solution over 10 minutes
Pseudohypoparathyroidism - define
Target cell insensitivity to PTH due to a mutation in a G-protein
↑ PTH
↓ calcium
↑ phosphate
Most common electrolyte abnormality during alcohol withdrawal and is a recognised cause of seizures?
Hypophosphataemia
Gitelman’s syndrome
Defect in the thiazide-sensitive Na+ Cl- transporter in the DCT
Normotension
Hypokalaemia
Hypocalciuria
Hypomagnesaemia
Metabolic alkalosis
Androgen insensitivity syndrome
X-linked recessive
End-organ resistance to testosterone causing genotypically male children (46XY) to have a female phenotype
SIADH - pathophysiology
Excessive release of antidiuretic hormone (ADH) - vasopressin, which leads to water retention, volume expansion, and dilutional hyponatraemia
Importantly, this increase in body fluid volume does not lead to the expected signs of fluid overload, such as oedema or hypertension, because the excess fluid is uniformly distributed throughout all body fluid compartments.
Statins in pregnancy?
Contraindicated
Cushing’s disease
pituitary adenoma → ACTH secretion
What test is used to differentiate between true Cushing’s and pseudo-Cushing’s.
Insulin stress test
Following radioiodine treatment, patients should avoid becoming pregnant for at least ?
6 months
Most common precipitating factors of DKA
Infection
Missed insulin doses
Myocardial infarction.
Fanconi syndrome
Disorder of proximal renal tubular function that leads to abnormal loss of bicarbonate, glucose, potassium, phosphate, uric acid and amino acids in the urine.
Patients have features of Type 2 RTA
Anticholinergics for urge incontinence in elderly people
Mirabegron
Most effective drug for treating hypertriglyceridaemia
Fibrates
Treatment for Myxoedema coma
IV thyroid replacement
IV fluid
IV corticosteroids (until the possibility of coexisting adrenal insufficiency has been excluded)
Anion gap
(sodium + potassium) - (bicarbonate + chloride)
A normal anion gap is 8-14 mmol/l
First-line in the management of nausea & vomiting in pregnancy/hyperemesis gravidarum
Anti-Histamines
(Cyclizine/Promethazine)
Gestational diabetes threshold
Fasting glucose is >= 5.6 mmol/L
2-hour glucose is >= 7.8 mmol/L
If at the time of diagnosis the fasting glucose level is >= 7 mmol/l insulin should be started
Hypokalaemia with hypertension
Cushing’s syndrome
Conn’s syndrome (primary hyperaldosteronism)
Liddle’s syndrome
11-beta hydroxylase deficiency
Hypokalaemia without hypertension
Diuretics
GI loss (e.g. Diarrhoea, vomiting)
Renal tubular acidosis (type 1 and 2**)
Bartter’s syndrome
Gitelman syndrome
Management for familial hypercholesterolaemia
1st + 2nd Line
- High dose Statin
- Ezetimibe
Urinary incontinence - first-line treatment:
Urge incontinence
Bladder retraining
Urinary incontinence - first-line treatment:
Stress incontinence
Pelvic floor muscle training
In thyroid storm, treat acutely with propylthiouracil or carbimazole
Propylthiouracil
In pregnancy, there is an increase in the levels of
Thyroxine-binding globulin (TBG)
Gitelman’s syndrome
Normotension
Hypokalaemia
Hypocalciuria
