Endocrinology Flashcards
acromegaly Cx
HTN, LVH, IHD, diabetes, sleep apnoea, arthritis, bitemporal hemianopia from pituitary tumour
adrenal insufficiency overview
primary AI - impairment of adrenal cortex - low cortisol/aldosterone
secondary AI - low cortisol from low ACTH
AI presentation
tanned, tired, toned, tearful
signs
- vitiligo
- tanned skin
- pigmentation (face, neck, palmar creases) - primary AI
- hypotension - loss of aldosterone
- dehydrated
- lean
symptoms
- lethargy, depression
- dizzy
- weight loss
- nausea/vomiting
- diarrhoea, constipation, abdo pain
- impotence/amenorrhea
Conn’s DDx
secondary hyperaldosteronism - excess renin and AgII release (renal artery stenosis can cause this)
Cushing’s syndrome overview
excess cortisol
Cushing’s disease overview
excess cortisol from inappropriate ACTH secretion - pituitary adenoma
Cushing’s Ix
Dexamethasone suppression test - usually suppresses cortisol level - failure to suppress is diagnostic
CT/MRI of adrenals/pituitary
DM Ix
random plasma glucose >11.1mmol/L
fasting plasma glucose >7mmol/L
OGTT >7mmol/L (>6 for impaired glucose tolerance)
HbA1c >6.5% normal (48mmol/mol)
Which T2DM drugs cause weight loss/gain?
Biguianide (metformin) - reduce glycogenolysis, gluconeogenesis, increase muscle uptake of glucose - weight loss
Sulfonylurea (gliclazide) - stimulate insulin release - weight gain, hypo risk
DPP4 inhibitors (sitagliptin) - no weight change
Glitazone (pioglitazone) - weight gain
DM complications
Macrovascular - atherosclerosis, stroke, IHD, PAD
Microvascular - diabetic retinopathy, nephropathy, neuropathy, infections
DKA, HHS, hypoglycaemia
DKA causes
Lack of insulin, glucose cannot be taken up by cells
FFAs -> acetyl-coA -> ketone bodies
excessive ketonegenesis
HHS/DKA differentials
HHS - hypovolaemia, marked hyperglycaemia without acidosis, higher osmolality
Hypoglycaemia
plasma glucose <3mmol/L
insufficient glucose to brain
Thyroid carcinoma Mx
Radioactive iodine
Levothyroxine (T4) - keep TSH reduced
Chemo
Partial/full thyroidectomy
Hypercalcaemia presentation
symptoms
bones - excess bone resorption - pain, fractures, osteoporosis
stones - biliary stones
groans - abdo pain, malaise, polydipsia, nausea
psychiatric moans - depression, anxiety
signs
QT shortening
Hypoparathyroidism
Low PTH
Primary - low due to parathyroid gland failure
Secondary - after parathyroidectomy/thyroidectomy
Pseudo - failure of target cell response to PTH
Pseudopseudo - same as pseudo but no Ca abnormalities
Hypoparathyroidism Ix
Bloods - calcium low, PTH low (high in pseudo)
ECG - long QT
Parathyroid ABs
SIADH Ix
FBC, U+E
Hyponatraemia, low plasma osmolality, high urine osmolality
acromegaly overview
excess growth hormone -> overgrowth of all organ systems
gigantism in children
acromegaly causes
pituitary adenoma secreting too much GH
acromegaly presentation
signs
- big hands, feet, jaw
- acral and soft tissue overgrowth
- big tongue, widely spaced teeth
- coarse facial features
- prognathism
symptoms
- arthralgia
- acroparaesthesia
- headache
- decreased libido
- acral enlargement
- wonky bite (malocclusion)
acromegaly DDx
pseudo-acromegaly - same physical appearance without elevated GH/IGF-1
acromegaly Ix
check IGF-1 levels (not GH, is pulsatile secretion)
oral glucose tolerance test - normally, rise in blood glucose suppresses GH levels
MRI pituitary fossa for adenomas
acromegaly Tx
transsphenoidal surgery
somatostatin analogues (IM octreotide) dopamine agonist (oral cabergoline) GH antagonist (pegvisomant)
radiotherapy
AI causes
primary
- worldwide, TB
- in UK - autoimmune adrenalitis (Addison’s disease)
- adrenal metastases, long term steroid use, opportunistic infections
secondary
- long term steroid therapy
- hypothalamic-pituitary disease - tumours, trauma, surgery
AI Ix
Bloods - hyponatraemia, hyperkalaemia (low aldosterone), hypoglycaemia (low cortisol)
Synacthen test
measure plasma cortisol before/30min after IM tetracosactide (ACTH analogue), cortisol remains low in primary AI, increases in secondary
Adrenal ABs - 21 hydroxylase AB in Addisons
AXR/CXR
AI Tx
primary
acute - IV hydrocortisone, saline, glucose infusion
oral hydrocortisone/prednisolone (glucocorticoids) oral fludrocortisone (mineralocorticoid)
secondary
oral hydrocortisone
AI Cx
Adrenal crisis - acute lack of cortisol (tx hydrocortisone)
Reduced QoL
Osteoporosis (from regular steroids)
Conn’s syndrome overview
primary hyperaldosteronism
excess aldosterone production -> increased sodium, water retention
Conn’s causes
2/3 - adrenal adenoma
1/3 - bilateral adrenocortical hyperplasia
Conn’s presentation
Often asymptomatic
Hypertension
Metabolic alkalosis
Hypokalaemia - weakness/cramps, paraesthesia, polyuria/polydipsia
Conn’s Ix
U/E
Spot renin/aldosterone levels - aldosterone raised, renin low
ECG - hypokalaemia
CT/MRI adrenals
Conn’s Mx
Aldosterone antagonist - oral spironolactone
Laproscopic adrenalectomy
Conn’s Cx
Cx from HTN - stroke, MI, kidney failure
Cushing’s syndrome causes
ACTH-dependent (high ACTH)
Cushing’s disease - ACTH-secreting pituitary tumour
ACTH-producing tumour elsewhere
ACTH-independent (low ACTH due to -ve feedback from raised cortisol)
adrenal tumour releasing cortisol
oral steroids
Cushing’s presentation
CUSHING Cataracts Ulcers Skin - striae Hypertension, hyperglycaemia Infections increase Necrosis Glucosuria
Central obesity, wasted limbs Moon face Buffalo hump Acne, hirsuitism, weight gain Mood change, gonadal dysfunction, protein wasting
Cushing’s DDx
Pseudo-Cushing’s - same presentation, not from pituitary-adrenal axis problems - eg prolonged excess alcohol consumption
Cushing’s Tx
Cushing’s disease - transphenoidal removal of pituitary adenoma
Adrenal adenoma - adrenalectomy
Adrenal carcinoma - radiotherapy, adrenolytic drugs (mitotane)
Ectopic ACTH - surgery if tumour located, drugs that inhibit cortisol synthesis (metyrapone, fluconazole)
Cushing’s Cx
HTN, metabolic syndrome, diabetes, obesity, coagulopathy, osteoporosis, Nelson’s syndrome
Nelson’s syndrome
increase skin pigmentation from ACTH increase from enlarging pituitary tumour after adrenalectomy (remove negative feedback against ACTH)
Diabetes mellitus
deficiency/diminished effectiveness of insulin, hyperglycaemia
T1DM
body fails to produce sufficient insulin
prone to DKA
T2DM
resistance to insulin
Gestational diabetes
high blood glucose levels in pregnancy
Maturity-onset diabetes of the young (MODY)
autosomal dominant form of T2DM - single gene defect altering beta cell function
secondary diabetes
inc pancreatic disease, endocrine…
T1DM causes
autoimmune
idiopathic
genetic component
T2DM causes
decreased insulin secretion/increased resistance
obesity, lack of exercise, calorie excess
polygenic
T1DM risk factors
Northern European, family history, other autoimmune disorders
T2DM risk factors
FHx, increasing age, obesity, poor exercise, ethnicity, overweight around abdomen
DM presentation
signs
ketonuria (ketoacidosis) - pear drop breath (T1)
complications (eg retinopathy)
symptoms
polyuria/nocturia
polydipsia
weight loss
T1 - leaner than T2
T1DM Mx
synthetic human insulin
short acting insulins - eg for before meals
sort-acting insulin analogues - fast onset, eg with evening meal
longer-acting insulins - 12-24hrs
complications - hypoglycaemia, weight gain
T2DM Mx
1st line - lifestyle - diet, exercise, weight loss, ramipril/statins/orlistat
2nd - oral metformin
Add sulfonylurea (oral gliclazide)
later - insulin/glitazone (oral pioglitazone) - increase tissue sensitivity to insulin
DKA overview
Ketonaemia (/ketonuria)
Hyperglycaemia
Acidosis
DKA presentation
signs
Pear drop breath
Kussmaul’s respiration (deep, rapid)
Disturbance of consciousness
symptoms Vomiting Drowsiness Abdo pain Dehydration - eyes sunken, slow cap refill, tachycardia, weak pulse, hypotension
DKA DDx
alcoholic ketoacidosis, hyperosmolar hyperglycaemic state, lactic acidosis
DKA Ix
Bloods show: hyperglycaemia, raised plasma ketones, acidaemia, metabolic acidosis with bicarb reduced
Urine stick testing - glycosuria and ketonuria
Check plasma osmolality and anion gap (both elevated, plasma osmolality more elevated in HSS)
DKA Tx
ABCDE
Replace fluid loss with 0.9% saline
Restore electrolye (K) loss and acid-base balance
Insulin-glucose
DKA Cx
Cerebral oedema, pulmonary oedema, hypotension, coma, hypothermia…
Hyperosmolar Hyperglycemic State (HHS)
Acute
Hyperglycaemia, hyperosmolality, mild/no ketoacidosis
HHS causes
Uncontrolled T2DM
HHS presentation
signs dehydration reduced consciousness bicarb not lowered tachycardia, hypotension
symptoms
generalised weakness
nausea/vomiting
bed-bound, confused, lethargic
HHS Ix
Hyperglycaemia
Urine stick - glycosuria
Plasma osmolality high
HHS Tx
Fluids - saline
Insulin
LMWH - eg enoxaparin - reduce risk of thromboembolism
Restore electrolyte loss (K)
HHS Cx
Ischaemia/infarction, vascular cx, ARDS, cerebral oedema (rapid lowering of blood glucose)
Hyperthyroidism
Excess TH
Primary - pathology in thyroid gland
Secondary - thyroid gland stimulated by excessive TSH
Primary hyperthyroidism causes
Graves disease - autoimmune induced excess TH secretion, diffuse goitre,
Toxic multinodular goitre - nodules that secrete TH
Adenoma
Thyroiditis (De Quervain’s) - transient, inflammation of thyroid
Drug-induced - amiodarone, iodine, lithium
Secondary hyperthyroidism causes
TSH-secreting pituitary adenoma
TH-resistance syndrome
Gestational thyrotoxicosis
Hyperthyroidism presentation
signs Graves ophthalmopathy - retro-orbital inflammation, protruding eye diffuse goitre hyperkinesis muscle wasting thin hair lid lag and stare, lid retraction onycholysis (nail separation from nail bed)
symptoms palpitations diarrhoea weight loss oligomenorrhea heat intolerance irritability/anxiety
Hyperthyroidism Ix
TFTs - T4/3 raised (TSH raised in secondary)
ABs against thyroid peroxidase and thyroglobulin (Graves)
Ultrasound thyroid, thyroid uptake scan
inflammatory markers
TSHR-Ab raised - diagnostic of Graves
Hyperthyroidism Tx
(IV methylprednisolone - for inflammation)
BBs (propanolol)
PTU (propylthiouracil) - stops T4 ->T3
Oral carbimazole - blocks TH synthesis - AGRANULOCYTOSIS risk (sore throat, fevers)
Radioactive iodine
Thyroidectomy
Thyroid crisis
acute complication - rapid T4 increase
hyperpyrexia, tachycardia…
precipitated by stress
Tx - oral carbimazole, oral propranolol, oral potassium iodide, IV hydrocortisone
Hypoglycaemia causes
In diabetics - insulin/sulfonylurea tx
Non-diabetics - EXPLAIN
Ex - exogenous drugs, insulin, alcohol
P - pituitary insufficiency
L - liver failure
A - Addison’s disease (lack of anti-insulin hormone function)
I - islets cell tumour, immune hypoglycaemia
N - non-pancreatic neoplasm
Hypoglycaemia presentation
Sweating, anxiety, hunger, tremor, palpitations, dizziness
Confusion, drowsiness, visual trouble, seizures, coma
(neuroglycopenia)
Hypoglycaemia Ix
Fingerprick blood test
Bloods - glucose, insulin, C-peptide, plasma ketones
Hypoglycaemia Mx
Oral sugar, long-acting starch
IV glucose 50%
IM glucagon
Hypothyroidism
Lack of TH
Primary - thyroid gland disease
Secondary - hypothalamic/pituitary disease
Hypothyroidism causes
Autoimmine - antithyroid autoantibodies - atrophy, no goitre
Thyroiditis (Hashimoto’s - is autoimmune) - atrophy, goitre
Post-partum thyroiditis
Thyroidectomy/radioactive iodine
Drug-induced - carbimazole, lithium, amiodarone
Iodine deficiency
Hypothyroidism presentation
signs - BRADYCARDIC Bradycardia Reflexes relax slowly Ataxia Dry, thin hair/skin Yawning/drowsy/coma Cold hands/temp drop Ascites Round puffy face Defeated demeanour Immobile/ileus (peristalsis stops) CCF
symptoms hoarse voice goitre constipation cold intolerant weight gain myalgia low mood hair/eyebrow loss cold pale skin
Hypothyroidism Ix
TFTs - TSH high in primary, low in secondary, T4 low
Bloods - anaemia…
Hypothyroidism Tx
Oral levothyroxine (T4)
Myxoedema coma
Severe hypothyroidism, acute emergency
hypothermia, cardiac failure, hypoventilation, hypoglycaemia, hyponatraemia
IV/oral T3 and glucose infusion
Thyroid carcinoma
Papillary - local spread
Follicular - spread to lung/bone
Anaplastic - aggressive
Lymphoma - non-Hodgkins
Medullary cell - calcitonin C cells
Thyroid carcinoma presentation
signs
thyroid nodule
cervical lymphadenopathy
symptoms
dysphagia, hoarseness of voice
Thyroid carcinoma Ix
Fine needle aspiration cytology biopsy
Bloods - TFTs
Ultrasound thyroid
Diabetes insipidus
Hyposecretion/insensitivity to ADH
Passage of large volumes of dilute urine
Cranial DI - reduced ADH secretion from pos pit
Nephrogenic DI - impaired response of kidney to ADH
Hyposecretion/insensitivity to ADH
Passage of large volumes of dilute urine
Cranial DI - reduced ADH secretion from pos pit
Nephrogenic DI - impaired response of kidney to ADH
Cranial
Genetics, hypothalamus disease, tumour, trauma
Nephrogenic
Hypokalaemia, hypercalcaemia, CKD, drugs, renal tubular acidosis, mutation of ADH receptor, pregnancy
DI presentation
signs
24hr urinary collection >3L/24hr
symptoms
polyuria
polydipsia, chronic thirst
nocturia
DI Ix
24hr urine collection test
Fluid deprivation test - restrict fluid, measure urine osmolality - if low then DI
Desmopressin:
High urine osmolality - cranial DI
Low - nephrogenic DI
MRI pituitary, hypothalamus
DI Tx
Cranial - oral desmopressin
Nephrogenic - treat cause, thiazide diuretics (oral bendroflumethiazide) - produce mild hypovolaemia, encourage kidneys to reabsorb Na and water, NSAIDs (ibuprofen) - lower urine vol and plasma Na
Hypercalcaemia
High Ca serum levels
Hypercalcaemia causes
Primary hyperparathyroidism
Malignancy - ectopic production of PTH-related peptide, osteolytic hypercalcaemia
Hypercalcaemia Ix
Raised corrected calcium levels
PTH low in cancer, high in primary hyperparathyroidism
Low albumin
24hr urinary Ca, ECG, CT/MRI
Hypercalcaemia Tx
Rehydrate with saline
Bisphosphonates - prevent bone resorption - IV pamidronate
Oral prednisolone
Hypercalcaemia Cx
Osteoporosis, kidney stones, renal failure, abnormal heart rhythm, nervous system problems
Hyperparathyroidism
Too much PTH secretion
Primary - parathyroid gland makes too much PTH
Secondary - increased PTH secretion in response to low calcium
Tertiary - autonomous secretion of PTH
Hyperparathyroidism causes
Primary - adenoma, hyperplasia
Secondary - is compensation of hypocalcaemia (from CKD/vit D deficiency)
Tertiary - after many years of secondary - CKD
Hyperparathyroidism presentation
primary
bones, stones, groans, moans
hypertension, short QT
secondary
like CKD - skeletal/CV complications
tertiary
like primary
Hyperparathyroidism Ix
Bloods - PTH, calcium, phosphate, ALP
PTH high in all
Calcium high in 1, 3, low in 2
Phosphate high in 2, 3, low in 1
ALP high in all
Hyperparathyroidism Mx
Surgical removal
Calcimimetic - increases sensitivity of parathyroid to Ca, less PTH secretion - eg oral cinacalcet
Bisphosphonates - alendronate - prevent loss of bone density
Hyperparathyroidism Cx
Hypocalcaemia, recurrent laryngeal nerve injury (from surgery)
Hypocalcaemia
Ca deficiency
Hypocalcaemia causes
HAVOC
Hypoparathyroidism Acute pancreatitis Vit D deficiency Osteomalacia CKD
Hypocalcaemia presentation
SPASMODIC
Spasms - Trousseau's sign Perioral paraesthesia (+cramps/tetany) Anxious, irritable, irrational Seizures Muscle tone increases in SM, wheeze Orientation impaired and confusion Dermatitis Impetigo herpetiformis Chvostek's sign, cataract, cardiomyopathy - long QT
Hypocalcaemia Ix
Low serum Ca
Serum urine and creatinine, eGFR - test for renal disease
ECG
Hypocalcaemia Mx
Acute - IV calcium gluconate
Vit D deficiency - oral colecalciferol/ADCAL
Hypoparathyroidism - calcium supplements + calcitriol (active vD)
Hypoparathyroidism causes
1 - parathyroid gland failure - autoimmune
2 - after (para)thyroidectomy, radiation, hypomagnesaemia
Pseudo - end-organ resistance to PTH
Hypoparathyroidism presentation
SPASMODIC
dry, scaly, puffy skin, brittle nails, coarse hair
Pseudo - short stature, short 4/5 metacarpals, subcut calcification
Hypoparathyroidism Mx
Acute - IV calcium
calcium supplements and calcitriol
Hypoparathyroidism Cx
Due to hypocalcaemia
laryngospasms, neuromuscular irritability (cramps/tetany), arrhythmias, stunted growth…
Pheochromocytoma
Catecholamine secreting tumour
Pheochromocytoma causes
Inherited (more noradrenaline)
Spontaneous (more adrenaline)
Pheochromocytoma presentation
signs hypertension postural hypotension tremor tachycardia
symptoms headaches palpitations sweating tremor anxiety/nausea
Pheochromocytoma Ix
24hr urine collection for catecholamines and metabolites
Blood tests
CT/MRI - locate tumour
Pheochromocytoma Mx
Surgery
Alpha blocker (phenoxybenzamine), beta blocker
Prolactinoma
benign, prolactin-producing tumour of pituitary gland
Hyperprolactinaemia causes
pituitary tumour
antidopaminergic drugs, antidepressants
head injury
Prolactinoma presentation
Tumour - headaches, bitemporal hemianopia
menstrual irregularity
infertility
galactorrhoea
hypogonadism
Prolactinoma Ix
check serum prolactin levels
Prolactinoma Tx
dopamine agonist - cabergoline
transsphenoidal pituitary resection
Prolactinoma Cx
Vision loss, osteoporosis (from hypogonadism)
Carcinoid tumours
Tumours of neuroendocrine/enterochromaffin cells - secrete serotonin/bradykinin
In gut, gallbladder, kidney …
Carcinoid syndrome
hepatic involvement of carcinoid tumours
Serotonin effects
bowel function mood clotting nausea bone density vasoconstriction increase force of contraction and HR
Carcinoid tumours presentation
Most asymptomatic, maybe weight loss, pain, palpable mass
signs
CCF
symptoms neck/face flushing bronchocontriction/bronchospasm appendicitis/obstruction RUQ pain diarrhoea
Carcinoid tumours Ix
Liver ultrasound
Urine - high conc of 5-hydroxylindoleacetic acid (metabolite of serotonin)
X-ray/CT/MRI
Carcinoid tumours Mx
Octreotide/lanreotide - somatostatin analogs - block serotonin release
Surgical resection
Carcinoid crisis
Tumour outgrows blood supply/is handled too much in surgery - mediators flow out
Tx - octreotide high dose
Hyperkalaemia
Serum K >5.5mmol/L
Hyperkalaemia causes
Renal - AKI, CKD, K-sparing diuretics, drugs that interfere with RAAS (NSAIDs)
Increased circulation of K - exogenous/endogenous - eg trauma, mass loss of K from cells
Shift from IC to EC space - acidosis, medications
Pseudo - eg tourniquet on too long
Hyperkalaemia presentation
Cardiac arrest might be first presentation
Maybe associated with metabolic acidosis
signs
bradycardia, tachypnoea
muscle weakness, flaccid paralysis
depressed tendon reflexes
symptoms
weakness, fatigue, muscular paralysis, SOB, palpitations/chest pain
Hyperkalaemia Ix
Bloods - high K
ECG - absent P, long PR, wide QRS, tall tented T - go, go long, go wide, go tall = gonner, sine wave pattern
Hyperkalaemia Mx
IV calcium gluconate - reduces excitability of cardiac myocytes
Insulin-glucose infusion - drive K into cells
Non-urgent - calcium polystyrene sulfonate resin - reduces K gut uptake
Hypokalaemia
Serum K <3.5mmol/L
Hypokalaemia causes
Increased renal secretion - thiazide/loop diuretics, increased aldosterone secretion (Cushing’s/Conn’s)
Exogenous mineralocorticoids
Redistribution to cells
GI losses
Reduced dietary intake/inadequate K replacement in fluids
Hypokalaemia presentation
usually asymptomatic
signs muscle weakness hypotonia hyporeflexia tetany
symptoms constipation palpitations light-headedness cramps
Hypokalaemia Ix
Bloods - low serum levels
ECG - small/inverted T waves, ST depression, U waves (PR prolongation)
Hypokalaemia Mx
Treat underlying cause
mild - oral K supplements (oral Sando-K)
Severe - IV K
SIADH
Syndrome of inappropriate secretion of ADH
too much ADH
dilute plasma, excess BV, hyponatraemia
SIADH causes
Neurological - eg trauma, tumour
Pulmonary - cancer, pneumonia…
Malignancy
Drugs - thiazide diuretics, SSRIs, PPIs
SIADH presentation
signs
GCS reduction, confusion, drowsiness
fits/coma
concentrated urine
symptoms
anorexia/nausea, malaise
weakness/aches
SIADH Tx
Underlying cause, restrict fluids
Hypertonic saline
Oral tolvaptan - vasopressin antagonist
Salt and loop diuretic - oral furosemide - if severe
SIADH Cx
Cx of hyponatraemia - gait disturbance, falls, cerebral oedema
