Flashcards in Endocrinology Deck (94):
Over what time period do insulin levels decrease from low->none in DM1?
Over a year or 2
What is MODY?
Maturity Onset Diabetes of the Young - like DM2 but presenting in kids, needs less insulin than expected
Autosomal dominant insulin defect of mitochondria
4 Ts of diabetes presentation? 2 extra Sx?
Thin (not necessarily for 2)
+ xerostomia and hunger
Biochemical diagnosis of DM?
Random glucose > 11.1
Fasting glucose > 7.0 (2 hours post prandial >11.1)
If symptomatic, diagnostic. Otherwise repeat tests
Biochemical requirements for impaired glucose tolerance?
Biochemical requirements for impaired fasting glucose?
Fasting glucose 6.1-7
2 hour post prandial
What 2 conditions constitute prediabetes?
Impaired glucose tolerance
Impaired fasting glucose
What is used for the oral glucose tolerance test?
HbA1c criteria for diagnosing DM2?
Name some contraindications to HbA1c use in diagnosing DM?
Increased red cell turnover - pernicious anaemia, acute blood loss, haemolytic anaemia, malaria, haemaglobinopathies e.g. Thalassaemia
Pregnancy, liver disease, renal disease
Underlying problem in DM2?
Peripheral insulin resistance so relative deficiency, eventually leading to B cell failure
4 causes of secondary DM?
3 macrovascular complications of DM?
3 microvascular complications of DM?
What basic abnormality in DM causes microvascular complications?
What basic abnormalities cause macrovascular complications in DM?
High BP and lipids
Initial management of prediabetes?
Lifestyle - exercise, weight loss
6 monthly or annual checks
Aim for 5-10% body fat drop over year
Initial management of DM2?
Reassess lifestyle factors
2 major contradictions to metformin?
Renal disease - creatinine > 150
Contrast scans (stop before)
Major side effects of metformin?
GI upset - MR preparations for this
Lactic acidosis risk
Major benefits of metformin?
Low risk of hypos
Major side effects of sulfonylureas e.g. Gliclazide, glibenclamide?
Risk of hypos
3rd line drug for DM management?
Thiazolidinediones e.g. Pioglitazone
How does Pioglitazone work?
Bit like biguanides/metformin
Treats underlying peripheral insulin resistance, delaying decline in B cell function
Major SEs of pioglitazone?
Risk of oedema (contraindicated in heart failure)
Weight gain + dilutional anaemia
Distal limb fractures
Advantage of Pioglitazone over metformin?
Can be used in renal failure
How do DDP4 inhibitors (gliptins) work?
Gliptin effect - increase endogenous GLP1
Benefits of gliptins?
Safe in renal impairment
What is exenatide?
GLP1 agonist - suppresses appetite so induces weight loss, promotes insulin secretion, preserves B cell function
What is the gliptin effect?
Insulin secretion via GLP1 agonist action, caused by GLP agonists e.g. Exenatide and gliptins (DD4 inhibitors)
Side effects of GLP1 agonists (exenatide)?
Nausea, GI upset
3 SEs of insulin therapy?
What constitutes a hypoglycaemia?
BM 4 or less (4 is the floor)
Causes of hypoglycaemia?
Missed or late meals
Too much insulin
Increased physical activity, high temperature
Alcohol (delayed onset)
Symptoms of hypoglycaemia?
Sympathetic response - sweat, tachy, palps, paraesthesia, cold, pale, dilated pupils, anxiety
Nausea, vomiting, headache
Neuro change - decreased consciousness, confusion, irritability, fatigue, lethargy, visual and speech changes
Management of hypo?
Dextrose/sugar if oral available
Follow with complex carb meal e.g. Sandwich
Don't miss out insulin subsequently!
Causes of DKA?
Illness and infection
Mechanism for DKA?
Low insulin -> mega high glucose -> osmotic diuresis
Lipolysis -> fatty acids -> ketone conversion in liver -> metabolic acidosis
Hyperglycaemic symptoms of DM?
Dehydration -> hypovolaemic shock
Ketoacidotic symptoms of DKA?
Nausea and vomiting
Abdo pain -> acute abdomen
SOB, deep laboured Kussmaul breathing (ketotic breath)
-> LoC, coma, cerebral oedema, DIC
Investigations for DKA?
Glucose and ketones (dip)
BM > 15 but lower than in HHS
ABG - metabolic acidosis +/- respiratory compensation
Management of DKA?
Fluid replacement - bolus if shocked
Monitor potassium as insulin can induce hypokalaemia
What is HHS/HONK?
Hyperosmolar hyperglycaemic state
Hyperosmolar non-ketotic state
Typical of DM2 as small amount of insulin inhibits lipolysis
Causes of HHS?
Poor glycaemic control
Medications - diuretics (low blood volume), steroids, B blockers/Ca channel blockers
Glucose levels in DKA vs HONK?
DKA > 15
HHS > 33 but often well over 40 or 50
What is LADA?
Latent Autoimmune Disease of Adulthood - like DM1 but presents as adult
3 common causes of hyperthyroidism?
Toxic multinodular goitre
2 medications that can induce hyperthyroidism?
Symptoms of hyperthyroidism?
Signs of hyperthyroidism?
Fast, irregular pulse
Warm sweaty skin
4 graves-specific signs of hyperthyroidism?
Blood tests to investigate hyperthyroidism?
Thyroid function - low TSH, high T4 and T3
Imaging that might be useful in thyroid disease?
Medical management of hyperthyroidism?
Symptomatic relief via B blockers
-> surgical removal
Alternatives to carbimazole for hyperthyroidism? Under what circumstances?
Doesn't cross placenta so safer in pregnancy
Rare side effects of carbimazole?
Bone marrow suppression - neutropenia, agranulocytosis
Complications of hyperthyroidism?
Heart disease - AF, heart failure, cardiomyopathy, angina
Pregnancy related complications
Common causes of hypothyroidism?
Iodine deficiency atrophic hypothyroidism
Iatrogenic (thyroidectomy or radio-iodine)
Symptoms of hypothyroidism?
Signs of hypothyroidism?
Dry skin, thin hair
Round puffy face
Goitre in Hashimotos
Medical management of hypothyroidism?
Titrated dose levothyroxine
Complications of hypothyroidism?
Heart disease via hypercholesterolaemia
Carpal tunnel syndrome
MSK complication of hypothyroidism?
Carpal tunnel syndrome
2 substances that parathyroid glands control?
What does PTH do and how?
Increases Ca levels in blood via increased osteoclast activity, active Ca resorption in kidneys and intestinal absorption via vit D
What does calcitonin do?
Decreases Ca in blood via inhibition of osteoclast/increased osteoblast activity, decreased intestinal absorption and decreased resorption in kidneys
What is the main purpose of calcitonin?
To prevent bone loss in hypocalcaemia, pregnancy, lactation etc. and to prevent postprandial hypercalcaemia
Symptoms of hyperparathyroidism?
Bone pain, tenderness due to breakdown
Weakness, fatigue, myalgias
Common cause of hyperparathyroidism?
Chronic renal disease
Vitamin D deficiency
Essentially Ca deficiency -> increased PTH
Symptoms of hypoparathyroidism?
Paraesthesia around hands, feet, mouth
Muscle spasms, tetany, cramps
Fatigue, bone pain, headaches, abdo pain
CATS Go numb of hypocalcaemia?
Tetany and hyperreflexia
Go numb - numbness and paraesthesia in hands, feet, mouth
4 causes of Cushing's syndrome?
Cushing's disease (pituitary ACTH secreting tumour)
Iatrogenic - exogenous steroids
Adrenal adenoma - increased cortisol
Ectopic ACTH secreting tumour e.g. Small cell lung cancer
Symptoms of Cushing's syndrome?
Mood change - depression, psychosis
Proximal muscle weakness
Gonadal dysfunction - hirsutism, ED, irregular menses
Signs of Cushing's syndrome?
Central obesity + abdominal striae
Moon face and buffalo hump
Thin skin (plethoric) and easy bruising
2 steps of investigations for Cushing's syndrome?
Confirm Cushing's syndrome
How do you confirm Cushing's syndrome?
Dexamethasone suppression test overnight
For Cushing's ACTH will be high in the morning
How to determine the cause of Cushing's syndrome once confirmed?
Measure ACTH - if high, Cushing's disease or ectopic tumour
If low, adrenal adenoma
Next line of investigation when Cushing's confirmed and ACTH measured?
MRI pituitary +/- adrenal CT +/- whole body CT
Management of Cushing's disease?
Trans-sphenoidal surgical removal
5 major complications of Cushing's syndrome?
Major causes of Addison's disease?
Primary disease of adrenals (autoimmune)
Rapid cessation of exogenous steroids
Signs and symptoms of Addison's disease?
Weight loss, anorexia
Tanning (increased MSH), pigmented palmar creases, vitiligo
Dizziness, postural hypotension
Symptoms of addisonian crisis?
What electrolyte disturbances may be visible in Addison's disease? What happens to blood glucose?
Gold standard test for Addison's disease?
Synacthen test - measure cortisol, give synacthen then measure at 30 mins
Cortisol > 550 excludes diagnosis
Then measure ACTH - will be high in primary Addison's, low in pituitary causes
Management of Addison's disease?
Corticosteroids (hydrocortisone) for life
Consider mineralocortoids e.g. Fludrocortisone
What needs to be adjusted if an Addisonian patient becomes unwell, increase exercise or is stressed?
Increase steroid dose
Hormones secreted by the anterior pituitary?
Hormones secreted by the posterior pituitary?
Differentials for polyuria and polydipsia?
2 blood tests that can be used in investigating DM 1?
GAD - glutamic acid decarboxylase
Islet cell autoantibodies
What endocrine disease yields ankle jerks?
What do ankle jerks in terms of thyroid disease?