Endocrinology Flashcards
What is hyperuricaemia associated with?
Hyperlipidaemia, hypertension, metabolic syndrome
What are the enzyme abnormalities in Gitelman’s syndrome?
hypokalaemia, hypocalciuria, hypomagnesaemia
What are the diagnostic thresholds for gestational diabetes?
FG >= 5.6, 2-hr glucose >= 7.8
What threshold for FG should insulin be started in gestational diabetes?
FG >= 7.0
What causes predominantly hypercholesterolaemia rather than hypertriglyceridaemia?
nephrotic syndrome, cholestasis, hypothyroidism
What causes predominantly hypertriglyceridaemia rather than hypercholesterolaemia?
diabetes, obesity, alcohol, chronic renal failure, drugs, liver disease
What is the MOA of meglitinides?
bind to an ATP-dependent K+(KATP) channel on the cell membrane of pancreatic beta cells
What are the three symptoms of Pendred’s syndrome?
bilateral sensorineural deafness, mild hypothyroidism and goitre
What is the MOA of evolocumab?
prevents PCSK9-mediated LDL receptor degradation
What is the MOA of fibrates?
Increase lipoprotein lipase activity via PPAR-alpha agonism
What is the MOA of ezetimibe?
reduces intestinal absorption of cholesterol
What is cholesterol a precursor to?
steroids, bile acids, vitamin D
also used to maintain cell membranes
What defect leads to familal hypercholesterolaemia?
Mutations in the LDL receptor gene (these are used for LDL clearance and breakdown to free cholesterol in the liver)
Which medication can increase fertility in PCOS?
Clomifene
Which medication is used to treat hyperthyroidism in the first trimester?
Propylthiouracil
Which medication is used to treat hyperthyroidism in the second and third trimester?
Carbimazole
What helps to determine the risk of fetal hypothyroidism when a mother is being treated for thyrotoxicosis in pregnancy?
thyrotrophin receptor stimulating antibodies at 30-36 weeks gestation
What is the treatment of myxoedemic coma?
Hydrocortisone and levothyroxine
Which type of MODY is most common and what gene is responsible?
MODY3 - HNF-1 alpha gene
Which gene is responsible for MODY2
glucokinase gene
Which gene is responsible for MODY5
HNF-1 beta gene
What is the diagnostic test for gastroparesis in DM
Isotrope gastric motility scintigraphy scan
What causes asymmetrical quadriceps wasting in DM
Diabetic amyotrophy (motor neuropathy)
What is the MOA of carbimazole
Blocks thyroid peroxidase from coupling and iodinating tyrosine residues on thyroglobulin - reducing thyroid hormone production
What antiglycaemic agent is linked with severe pancreatitis
exenatide
Which drugs cause SIADH
carbamazepine, sulphonylureas, SSRIs, TCAs
What condition describes lack of blood flow to the pituitary after blood loss during childbirth
Sheehan’s syndrome
what is seen in sick euthyroid syndrome
Low TSH, low thyroxine, low T3
what is the action of metformin in PCOS
increases peripheral insulin sensitivity
Which antibodies can be used to test for LADA
GAD
What is the first line investigation of Conn’s syndrome
Plasma aldosterone/renin ratio
What is the HbA1c target for a patient with T2DM on metformin
48
What is the HbA1c target for a patient with T2DM on a drug that may cause hypoglycaemia
53
Which insulin should a patient with T2DM start with
NPH insulin (intermediate-acting)
What is the first line treatment for remnant hyperlipidaemia
Fibrates
Which anti-diabetic medication is associated with increased risk of foot amputations
Canagloflozin
What levels of FSH and LH are seen in Kallmann syndrome
Low/normal
What levels of FSH and LH are seen in Klinefelter syndrome
Raised FSH and LH
What is the inheritance of Kallmann’s syndrome
X-linked recessive
When should statins be started in T1DM
age over 40yrs, had diabetes >10 years, established nephropathy, or has other CVD risk factors
What is the management of subclinical hypothyroidism in an asymptomatic person with TSH < 10
Watch and wait
What is the management of subclinical hypothyroidism in an asymptomatic person aged less than 70 with TSH >10
start levothyroxine
Which steroids have the lowest mineralocorticoid activity
dexamethasone, betmethasone
what are the endocrine deficiencies seen in autoimmune polyendocrinopathy syndrome (APS) type 2
Addisons + T1DM or autoimmune thyroid disease
what are the endocrine deficiencies seen in autoimmune polyendocrinopathy syndrome (APS) type 1
2 of: Addisons, chronic mucocutaneous candidiasis, primary hypoparathyroidism
What is the treatment of liddle’s syndrome
amiloride or triamterene
What is the central feature of MEN1
hyperparathyroidism
What is the difference between MEN2a and MEN2b
MEN2a has hyperparathyroidism, MEN2b has marfanoid body. (both have medullary thyroid cancer and phaeochromocytoma)
When should metformin be considered in T1DM
BMI > 25
What does nuclear scintigraphy show in toxic multinodular goitre
Patchy uptake
What causes excessive sweating in acromegaly
Sweat gland hypertrophy
What are the symptoms of MEN1
Peptic ulcer (from insulinomas/gastrinomas), hyperparathyroidism, pituitary disease
Which MEN gives a marfanoid body habitus
MEN 2b
Which MEN Types cause hyperparathyroidism
MEN1, MEN2a
What condition is associated with tendon and tuberous xanthoma
Familial hypercholesterolaemia
What is the treatment of familial hypercholesterolaemia
Max dose statins
Which condition is associated with palmar xanthoma
Remnant hyperlipidaemia
What is associated with eruptive xanthoma
Familial hypertriglyceridaemia, lipoprotein lipase deficiency
What features are diagnostic of metabolic syndrome
Central obesity + 2 of: raised triglycerides, low HDL, hypertension, raised fasting glucose
Where is leptin produced
Adipose
Where is ghrelin produced
Stomach/pancreas
Which condition is due to inhibition of lipoprotein lipase leading to raised triglycerides and recurrent abdominal pain
Chylomicronaemia syndrome
How is insulinoma diagnosed
72 hr fast - if symptoms develop check insulin and c-peptide
What is the MOA of fibrates
Activate PPAR alpha receptors - increases LPL activity
What percentage of insulinomas are malignant
10%
Which malignancy is necrolytic migratory erythema associated with
Glucagonoma
What is Wolfram’s syndrome
DIDMOAD - DI, DM, optic atrophy and deafness
What is the usual inheritance of nephrogenic DI
X-linked recessive
What is the treatment of nephrogenic DI
Indomethacin, thiazide, low sodium diet
What is the treatment of cranial DI
Fluids, vasopressin
What is the inheritance of Liddle’s syndrome
Autosomal dominant
Which inherited condition causes severe hypokalaemia due to defective Cl absorption at the Na-K-2Cl co-transporter in ascending loop of henle
Bartter’s syndrome
What is the treatment of Bartter’s syndrome
Spironolactone/Indomethacin
What is the inheritance of Bartter’s syndrome
Autosomal recessive
What electrolyte abnormalities are seen in Gitelman’s syndrome
Hypokalaemia, hypomagnesaemia and hypocalciuria
Where is the transport defect located in Gitelman’s syndrome
DCT (thiazide-sensitive Na-Cl transporter)
What is the main cause of hyperaldosteronism
Bilateral idiopathic adrenal hyperplasia
How do corticosteroids cause osteoporosis
Inhibit osteoblast activity and increase osteoblast apoptosis
What is the most accurate way to test for pituitary source of cushing’s
Inferior petrosal sinus sampling
Which antibodies are typically seen in Addison’s disease
Anti-2l hydroxylase antibodies
What are the causes of SIADH
Sulphonylureas, SSRIs, TCAs, antipsychotics, carbamazepine, thiazides, omeprazole, porphyrias
Where does phaeochromocytoma arise from
Chromaffin cells in medulla
Which conditions are associated with phaeochromocytoma
MEN2, neurofibromatosis, VHL
What causes increased IGF-1
Acromegaly, pregnancy
What complications are associated with acromegaly
Hypertension, diabetes, colorectal cancer, cardiomyopathy
What is the diagnostic test for GH deficiency
Insulin tolerance test - <10mg/L of GH released confirms diagnosis
What is the most important treatment in pituitary apoplexy
IV hydrocortisone
What test can be used to diagnose factitious hyperthyroidism
Low thyroglobulin
What are the most common antibodies in Grave’s disease
Anti-TSH receptor stimulating Abs (90%) (50% have TPO Abs)
What is toxic multinodular goitre
Thyroid gland contains multiple autonomously functioning thyroid nodules
What is the biggest risk factor for developing thyroid eye disease
Smoking
What pattern of thyroid disease does De Quervain’s have
Post viral: hyperthyroid -> hypothyroid -> euthyroid
Which HLA is associated with De Quervain’s thyroiditis
HLA B35
What is the treatment of De Quervain’s thyroiditis
Self limiting, no treatment required
What are the complications of subclinical hyperthyroidism
SVT, osteoporosis
Which antibodies are positive in Hashimoto’s thyroiditis
Anti-TPO, Anti-TG
Which drugs interfere with thyroxine absorption
Rifampicin, amiodarone, calcium, iron tablets, cholestyramine, sevelamer, PPIs
Which syndrome describes increased reverse T3, low T3 and T4 seen in ITU patients
Sick euthyroid syndrome
Which thyroid cancer is associated with FAP
Papillary
Which cancer associated with MEN2 secretes calcitonin
Medullary thyroid cancer
Which thyroid cancer is associated with local invasion and metastases
Anaplastic thyroid cancer
What does PTH do to calcium and phosphate
Increases plasma calcium, decreases plasma phosphate (by decreasing renal PO4 absorption)
What else causes hypercalcaemia other than PTH and malignancy
Thiazides, thyrotoxicosis, addisons
Which electrolyte abnormalities can cause nephrogenic diabetes insipidus
Hypercalcaemia, hypokalaemia
What is the pathophysiology of pseudohypoparathyroidism
Target cells insensitive to PTH
Which electrolyte disturbance results in hypocalcaemia
Hypomagnesaemia
Which inherited condition is characterised by impaired PO4 reabsorption in the renal tubules
Vitamin D resistant rickets
Which is more sensitive and specific for hypocalcaemia out of trosseau’s and chvostek’s sign
Trosseau’s sign ( carpal spasm with brachial artery occlusion)
Which neurotransmitter constantly inhibits prolactin
Dopamine
What are the causes of gynaecomastia
Testicular failure, liver cirrhosis, hyperthyroidism, spironolactone, cimetidine, omeprazole, goserelin
What is the treatment of hirsutism and acne in PCOS that doesn’t respond to COCP
Topical eflornithine
Which anti-hyperglycaemics can cause weight gain
Sulphonylureas, TZDs
What is the treatment of choice for toxic multinodular goitre
Radioiodine therapy
What are the causes of hyperprolactinaemia
Pregnancy, prolactinoma, physiological, PCOS, primary hypothyroidism, phenothiazines, metoclopramide, domperidone
What is the MOA of orlistat
Pancreatic lipase inhibitor
What BMI is orlistat indicated for
BMI >28 with RFs or >30
What is measured during dynamic pituitary function tests
GH, glucose, cortisol, TSH, LH, FSH
What is the starting plasma osmolality in a water deprivation test in a patient with psychogenic polydipsia
Low
What is the pattern of results seen in a water deprivation test in a patient with cranial diabetes insipidus
High starting plasma osmolality, low starting urine osmolality (<300), high urine osmolality after ADH (>600)
When should gestational diabetes be screened for in a women who has had GD in a previous pregnancy
As soon as possible after booking and at 24-28 weeks if first test is normal
What are the glucose targets for self-monitoring in pregnancy
Fasting 5.3; 1 hour after meals 7.8; 2 hours after meals 6.4
Which foods have a high glycaemic index
White rice, baked potato, white bread
How should metformin be adjusted for Ramadan
1/3 before sunrise, 2/3 after sunset
What are the adverse effects of pioglitazone
Weight gain, liver impairment, fluid retention (CI in HF, worse with insulin), bladder cancer, increased risk of fractures
What causes higher-than-expected levels of HbA1c
Vit B12/folate deficiency, IDA, splenectomy
What are the clinical features of pseudohypoparathyroidism
Low IQ, short stature, shortened 4th and 5th metacarpals, low calcium, high phosphate, high PTH
What indicates that a patient with T2DM might benefit from meglitinides
Erratic lifestyle - taken shortly before a meal
What are the contraindications to an insulin stress test for investigation of hypopituitarism
Epilepsy, IHD, adrenal insufficiency
What is the Simon Broome criteria
Used to diagnose familial hypercholesterolaemia: TC >7.5 and LDL >4.9, tendon xanthoma in pt or 1st/2nd degree relatives, FHx of MI <60 in 1st degree relative
What is the medical management of stress incontinence that doesn’t respond to pelvic floor exercises
Duloxetine
When is hypertonic saline indicated in hyponatraemia
Acute, severe, symptomatic hyponatraemia (<120)
Where are chylomicrons produced
GI tract - contain mostly triglycerides
Where are VLDLs produced
The liver - contain mainly triglycerides but some cholesterol
What is the main function of triglycerides
Energy source for tissues
What should a patient with hypothyroidism do with their thyroxine dose in pregnancy
Increase thyroxine dose by up to 50% as early as 4-6 weeks of pregnancy
What is the definitive diagnosis of remnant hyperlipidaemia (dysbetalipoproteinaemia)
Lipoprotein electrophoresis or genotyping of apo-protein E
What is the first test to do when excluding anyone with hyperprolactinaemia
Pregnancy test
What is Von Hippel Lindau syndrome
Phaeochromocytoma, renal cell carcinoma, retinal and cerebellar haemangioblastomas
What can lead to a false positive dexamethasone suppression test
Enzyme inducers (CYP450)
What is the best treatment of venous ulcers
Multi layer bandaging
What is the preferred anti-thyroid drug therapy in late pregnancy
Carbimazole
What is the initial follow up for patients with microprolactinomas
Yearly MRI
What is the treatment of Kallman’s syndrome
Pulsed GnRH
What disease is characterised by precocious puberty, cafe-au-lait skin pigmentation, polyostotic fibrous dysplasia and hyperthyroidism
McCune-Albright syndrome
What is the commonest cause of primary hyperthyroidism
Benign adenoma
What is the most common electrolyte abnormality in anorexia
Hypokalaemia
What is the treatment of ABPA
Oral corticosteroids + prolonged course of itraconazole
What is the treatment of DI after trans-sphenoidal surgery
IV desmopressin whilst matching fluid output with appropriate replacement (only a few will go on to need DDVAP long term)
What causes raised c peptide with low glucose
Sulfonylurea abuse (most common), insulinoma (very rare)
Which type of amiodarone-induced thyrotoxicosis has normal radioiodine uptake and normal IL-6
AIT type 1
What is the treatment of AIT type 1
Anti-thyroid drugs (e.g. carbimazole) and potassium perchlorate
Which AIT causes high IL-6
AIT type 2
What is the treatment of AIT type 2
Prednisolone 40mg/day
What is the treatment of amiodarone-induced hypothyroidism
Continue amiodarone and add levothyroxine
What is the treatment of grave’s ophthalmology with sight-threatening features
IV corticosteroids
What is the equation for plasma osmolarity
2(Na+K) + urea + glucose
What are the plasma osmolarity and glucose levels usually seen in HHS
Osmolarity >320
Glucose >30
What is the most useful marker of tumour recurrence of thyroid carcinomas after total thyroid ablation
Thyroglobulin
What can be used to diagnose medullary thyroid cancer
Pentagastrin stimulation test (measures calcitonin at 2 and 5 minutes - rise suggests cancer)
What joint condition is associated with T1DM due to HLA-DR4
Rheumatoid arthritis
What is present on 75% of MRI brain scans in Kallman’s syndrome
Absent olfactory bulbs (no sense of smell)
What is the management of insulin-related fluid retention
Furosemide
What is the initial treatment of a macroprolactinoma
Dopamine agonist - bromocriptine
Which condition can present with modest CK rise and muscle symptoms when untreated
Hypothyroidism
