Endocrinology Flashcards
What is the intial rate of insulin in DKA
0.1 units per kilo/hour
outline the treatment of acromegaly
Trans-sphenoidal surgery is the first-line treatment for acromegaly in the majority of patients
Dopamine agonists
for example bromocriptine
the first effective medical treatment for acromegaly, however now superseded by somatostatin analogues
effective only in a minority of patients
Somatostatin analogue directly inhibits the release of growth hormone for example octreotide effective in 50-70% of patients may be used as an adjunct to surgery
Pegvisomant
GH receptor antagonist - prevents dimerization of the GH receptor
once daily s/c administration
very effective - decreases IGF-1 levels in 90% of patients to normal
doesn’t reduce tumour volume therefore surgery still needed if mass effect
what is used to define ‘metabolic syndrome’
elevated waist circumference: men > 102 cm, women > 88 cm
elevated triglycerides: > 1.7 mmol/L
reduced HDL: < 1.03 mmol/L in males and < 1.29 mmol/L in females
raised blood pressure: > 130/85 mmHg, or active treatment of hypertension
raised fasting plasma glucose > 5.6 mmol/L, or previously diagnosed type 2 diabetes
what biochemical affect can SGLTs inhibitors have
increase cholesterol
give some drugs that can cause gynaecomastia
spironolactone (most common drug cause) cimetidine digoxin cannabis finasteride GnRH agonists e.g. goserelin, buserelin oestrogens, anabolic steroids
give a reason why Hba1c may be falsely higher than it is
Vitamin B12/folic acid deficiency
Iron-deficiency anaemia
Splenectomy
give reasons why hba1c may be falsely low
sickle cell anamia
G6PD deficiency
hereditory spherocytosis
what is exposure ketratopathy
damage to the cornea due to dryness caused by incomplete or inadequate eyelid closure, resulting in loss or insufficiency of the tear film.
a cause would be thyroid eye disease
what cancer is associated with acromegaly
colorectal
which hpv strains are associated with cervical cancer
16, 18 and 33
what is barters syndrome
an inherited cause (usually autosomal recessive) of severe hypokalaemia due to defective chloride absorption at the Na+ K+ 2Cl- cotransporter (NKCC2) in the ascending loop of Henle. It should be noted that it is associated with normotension (unlike other endocrine causes of hypokalaemia such as Conn’s, Cushing’s and Liddle’s syndrome which are associated with hypertension).
how do SGLT2 inhibitors work
reversibly inhibit sodium-glucose co-transporter 2 (SGLT-2) in the renal proximal convoluted tubule
what is the mechanism of action of the “gliptins”
DPP4 inhibitor - increase incretins e.g. GLP1 and GIP
what is gitelmans syndrome
rare autosomal recessive disorder which occurs due to a mutation causing a resorptive defect of the sodium chloride co-transporter. Its pathogenesis is similar to the mechanism of a thiazide diuretic. It is characterised by hypokalemia-hypomagnesemia and alkaline urine
what is the major complication of carbimazole therapy
agranulocytosis
what is the difference between cushings disease and syndrome
Cushing’s disease (80%): pituitary tumour secreting ACTH producing adrenal hyperplasia
what is the karyotype in klinefleters
47XXY
what is the first line test for assessing for acromegaly
insulin-like growth factor -1
not growth hormone as this level can vary depenfing on time of day
what is the best test to diagnose cushings
overnight dexamethasone suppression
if not available 24 hour urinary cortisol
what antibodies are found in hashimotos
anti tpo most commonly
what tablets can reduce the absoption of levothyroxine§
iron tablets
what is the first hormone secreted in reponse to hypoglycaemia
glucagon
tries to convert glycogen stores to glucose
what is the treatment of choice for hyperthyroidism in pregnancy
propylthiouracil
what causes increased sweathing in acromegaly
sweat glands hypertrophied
what is at increased risk in combined (ie progesterone and oestrogen) HRT therapies
breast cancer
what is liddle’s syndrome
is a rare autosomal dominant condition that causes hypertension and hypokalaemic alkalosis. It is thought to be caused by disordered sodium channels in the distal tubules leading to increased reabsorption of sodium.
Treatment is with either amiloride or triamterene
deafness + hypothyroidism =
pendred syndrome
how is mody typically inherited
autosomal dominent
what medication is associated with euglycaemic DKA
SGLT2 inhibitors
what features are associated with pseudohypoparathyroidsim
short stature
low IQ
short 4th and 5th metacarpals
which steroid has the least mineralocorticoid effect
dexamethasone
what metabolic abnormality occurs in cushings
hypokalaemic metabolic alkalosis
what increases the risk of fluid retention with pioglitazone
simulatansous use of insulin
best investigation for insulinoma
supervised fasting
what is riedals thyroiditis
Riedel’s thyroiditis is a rare cause of hypothyroidism characterised by dense fibrous tissue replacing the normal thyroid parenchyma. On examination a hard, fixed, painless goitre is noted. It is usually seen in middle-aged women. It is associated with retroperitoneal fibrosis.
name drugs which cause raised prolactin
metoclopramide, domperidone
phenothiazines
haloperidol
very rare: SSRIs, opioids
how does carbimazole work
blocks thyroid peroxidase from coupling and iodinating the tyrosine residues on thyroglobulin → reducing thyroid hormone production
how is phaeochromocytoma managed
surgery is definitve management but in mean time
alpha blockade given BEFORE beta blocker
what gene is most commonly associated with MODY
HNF-1 alpha gene
