Endocrinology Flashcards

1
Q

A patient has a large goitre with possibly some nodules, how should it be investigated?

A

TFTs
Ultrasound (cystic or solid? Aka typically benign or malignant)
Fine needle aspiration

Consider a radioiodine isotope scan to determine cause of hyperthyroidism- absent isotope uptake suggests inflammation or destroyed tissue

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2
Q

Which diseases put patients at risk of thyroid disease?

A
Hyperlipidaemia
Diabetes mellitus
Those on amiodarone (arrhythmia) or lithium (bipolar)
Down's or Turner's
Addison's
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3
Q

Signs of thyrotoxicosis not specific to Graves:

A
Underdressed for temperature
Warm moist skin
Fine tremor
Palmar erythema
Thin hair
Lid lag- eyelids lag behind the eye's descent
Lid retraction
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4
Q

3 Signs of Grave’s disease specifically:

A

1 Eye: opthalmaplegia, proptosis (exopthalmus is Grave’s is cause)
2 Pretibial myxoedema
3 Thyroid acropachy- clubbing, painful fingers and toes (Extreme manifestation)

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5
Q

Cause of Grave’s disease:

A

Circulating IgG autoantibodies that activate G-protein coupled thyrotropin) receptors

= smooth thyroid enlargement and increased hormone production

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6
Q

Causes of thyrotoxicosis:

A

Graves’ (2/3rds)
Toxic multinodular goitre (related to gene mutations, nodules secrete hormones)
Toxic adenoma (solitary nodule producing T4/3, rest of gland is supressed)
Ectopic thyroid tissue- metastatic follicular cancer
Exogenous- iodine excess, levothyroxine
Subacute De Quervain’s Thyroditis- postviral self limiting

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7
Q

How can you try to differentiate between Graves and multinodular goitre or toxic adenoma on palpation of the gland?

A

Graves- smooth diffuse enlargement
Toxic adenoma or multinodular goitre- more palpable nodules

Other nodular:
Carcinoma

Other diffuse enlargement:
Hashimoto’s, subacute De Quervain’s

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8
Q

Drug treatment of thyrotoxicosis:

A
  1. Propranolol
  2. Carbimazole (agranulocytosis SE) ± levothyroxine
    Inhibits the thyroid peroxidase enzyme iodinating the hormones
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9
Q

Risk of thyroidectomy? (Things to look for if someone has a thyroid placed scar)

A

Recurrent laryngeal nerve damage- hoarse voice

Hypoparathyroidism- tingling, burning sensation, muscle cramps

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10
Q

In which diseases might anti-thyroid peroxidase antibodies be present?

A

Graves disease

Or Hashimoto’s (chronic autoimmune hypothyroidism)

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11
Q

Signs of Graves eye disease:

A

I- Exopthalmus- appearance of protruding eye
Proptosis- eyes protrude beyond the orbit
Conjunctival oedema
Corneal ulceration
F- Papilloedema
A- Loss of colour plates
CNIII- opthalmaplegia from muscle swelling and fibrosis restricting movement

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12
Q

How is Graves eye disease treated?

A

Caused by lymphocyte infiltration and periorbital swelling:

Mild- symptomatic (artificial tears, sunglasses, avoid dust, elevate head at night, prisms on glasses for diplopia)

Severe- with opthalmaplegia or gross oedema:
IV methylprednisolone
Surgical decompression

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13
Q

What are the symptoms of hypothyroidism:

BRADYCARDIC

A
Bradycardia
Reflexes relaxing slowly
Ataxia (cerebellar)
Dry skin/hair
Yawning/drowsy
Cold hands + low T
Ascites ± non-pitting oedema ± pleural/pericardial effusion
Round puffy face
Defeated demeanor
Immobile
CCF

Neuropathy, myopathy

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14
Q

Causes of primary hypothyroidism:

A

Autoimmune- atrophic or Hashimoto’s (lymphocytic)
Iodine deficiency
Iatrogenic- thyroidectomy, radioiodine therapy, amiodarone, lithium
Subacute De Quervain’s- postviral (temporary)

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15
Q

What does POEMS syndrome stand for:

A
Polyneuropathy
Organomegaly
Endocrinopathy
M-protein band (plasmacytoma)
Skin tethering/pigmentation
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16
Q

How can amiodarone cause thyrotoxicosis and why may thyroid problems persist once stopped?

A

Has a cytotoxic effect on thyroid follicular cells, may cause a thyroiditis causing thyroid release

Amiodarone has a half life of 80 days

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17
Q

What effect does excess cortisol have?

A

In excess, it acts like aldosterone
Salt retention at the expense of H+ and K+
= hypokalaemic hypertensive alkalosis

Ie in Cushing’s, adrenal hyperplasia, ectopic ACTH

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18
Q

Patient has the signs of Grave’s disease but is euthyroid, what could the cause be?

A

Could still be Graves, before thyroid disease has occurred yet
There are TSH-receptors in the eye

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19
Q

Rx for grave’s

A

Carbimazole
Propylthiouracil

SE: agranulocytosis- rash, fever, sore throat

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20
Q

Features of MEN1?

A

Pituitary tumours
Pancreatic neuroendocrine tumours (VIPoma)
Parathyroid tumours- all 4 glands may be affected

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21
Q

What test can determine whether a patient has high Ca2+ because of a familial kidney condition?

A

Urine calcium should be low if they have benign hypocalciuric hypercalcaemia

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22
Q

Secondary causes of diabetes:

A

Drugs: steroids, thiazides, atypical antipsychotics (olanzepine)

PMH: CF, chronic pancreatitis, haemochromotosis, Cushing’s/phaeochromocytoma, acromegaly

MODY, gestational, DIDMOAD

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23
Q

Patient has random glucose of 10, what would your next line of investigation be?

A

Between 7-11 do a fasting glucose test

If fasting glucose is >7 do an oral glucose tolerance test
+ve if above 11

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24
Q

How long do you fast for before taking a fasting blood glucose?

A

8 hours

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25
How is an oral glucose tolerance test performed?
Fast for 8 hours 75mg of glucose Measure at 2 hours
26
Complications of diabetes:
Macrovascular: Stroke, peripheral arterial disease, MI Microvascular: Nerve, eyes, kidneys Acute: hypoglycaemic crisis, DKA
27
Types of thyroid carcinoma
Please Feel My Airway Lightly Papillary (commonest- orphan annie nuclei on histology) Follicular (female, favourable prognosis, faraway mets) Medullary (calcitonin, Men2 associated, Ca low) Anaplastic (old, poor survival) Lymphoma (A with Hashitomo's thyroiditis)
28
Tumour markers for thyroid cancers
Thyroglobin: follicular + papillary | Calcitonin
29
What are the electrolyte abnormalities classically associated with Cushing's?
Mineralocorticoid effect: low K+, high Na+ | Glucocorticoid effect: hyperglycaemia
30
Causes of Cushing's that are ACTH-dependent and independent
ACTH dependent: Pituitary adenoma (Cushing's disease) or hyperplasia, ectopic source ACTH independent: Adrenal hyperplasia, adrenal adenoma, exogenous Pseudo-Cushing's: severe depression, alcoholism
31
Tests for Cortisol if suspected:
1. Best: Urinary 24hr cortisol But often: Midnight cortisol 2. Low dose Dexamethasone test = confirms Dexamethasone at midnight, measure in AM 3. Measure ACTH = dependent or independent High- dependent Low- adrenal cause (CT or adrenal vein sampling) 4. High dose Dexamethasone = ?ectopic Low Cortisol- Cushing's disease in pituitary High Cortisol- Ectopic ACTH
32
Rx of Cushing's:
Pituitary adenoma: Ketoconazole then transphenoidal excision Adrenal site: Ketoconazole then adrenalectomy
33
Which is the more potent suppresser of TSH- T3 or T4?
T3
34
In someone taking levothyroxine, is it more important to measure T3 or T4?
T4 as this acts as the thyroid store, each cell converts as much of T4 as it needs into T3
35
What is Sheehan's syndrome?
Pituitary necrosis after postpartum haemorrhage hypovolaemia
36
What basal tests can be performed to look for hypopituitarism?
``` Low: LH and FSH Testosterone, oestradiol TSH, T4 IGF-1 (measures GH axis) Cortisol ``` High from disinhibition: Prolactin
37
What dynamic tests of pituitary function can be performed?
1. Short synacthen test: ACTH given and cortisol measured | 2. Insulin tolerance test: IV insulin, measure GH and cortisol increase
38
Which hormones are produced by the anterior and posterior pituitary gland?
Anterior: TSH, Prolactin, FSH, LH, ACTH Posterior: ADH, GH
39
Features of polycystic ovarian syndrome:
Oligomenorrhoea/amenorrhoea Infertility Obesity, acne, hirsutism
40
Causes of gynaecomastia
Oestrogens may be increased by: Tumours- testicular, adrenal, bronchial HCG producing Failure to convert them Hypogonadism Liver cirrhosis Hyperthyroidism
41
Causes of erectile dysfunction:
Big 3: smoking, alcohol and diabetes Endocrine: hypogonadism, high prolactin or thyroid, kidney/liver dysfunction Neurological: prostate or bladder surgery damage, MS, cord lesions, autonomic neuropathy Penile abnormalities: Peyronie's, post-priaprism Drugs: F DDAB (can't properly F) digoxin, diuretics, antidepressants, antipsychotics, b blocker, finasteride
42
Management of erectile dysfunction:
LFTs, U+Es, glucose, TFTs, LH, FSH, lipids, testosterone, prolactin 1. PDE5 inhibitor- sildenafil Inhibition prevents break down of cGMP, which activates Ca+ activated K+ channels to hyperpolarise and relax smooth muscle cells (= engorgement) Vacuum aids Intracavernosal injections Inflatable prostheses Bioengineered tissue engineering
43
CI to PDE5 inhibitors like sildenafil
PC: bleeding from peptic ulcer PMH: unstable angina, MI in 3 months, stroke Renal or liver impairment, hypertension, retinal disorders (PDE in the eye affected) DHx: concurrent nitrates
44
Causes of primary hypogonadism in males:
Chromosomal- XXY (Klinefelter's) Post orchitis- mumps, HIV, leprosy Local trauma- torsion, chemo Systemic- Renal failure, liver cirrhosis, alcohol excess (toxic to Leydig cells)
45
Causes of secondary hypogonadism:
Low LH and FSH: Hypopituitarism, Prolactinaemia Kallman's syndrome- isolated GnRH deficiency ± colour blind Systemic- COPD, HIV, DM, Age
46
Patient with end-stage renal failure, polydactyly and low IQ? Other features?
Laurence Moon syndrome Autosomal recessive- obesity, hypogenitalism, reduced body hair, azoospermia Retinitis pigmentosa Kidney- calyceal clubbing, cysts, diverticula
47
What affects does high aldosterone have?
Sodium and water retention Leading to reduced renin release from juxtaglomerular cells Renin release is stimulated by: 1. Sympathetic action (B1-adrenorecptors) 2. Low Na+ at DCT 3. Renal artery hypotension
48
Patient has a BP of 160/95 U+Es: K+ 3mmol Na+ 144mmol What endocrine cause is there?
Primary aldosteronism: Acts on ENaC to increase Na/K exchange at collecting duct Stimulates a proton-ATPase increasing proton excretion leading to a metabolic alkalosis
49
Causes of primary aldosteronism:
66% solitary adenoma of adrenals (Conn's syndrome) 33% adrenocortical hyperplasia Rarely: adrenal carcinoma Glucocorticoid-remediable aldosteronism
50
What is the pathophysiology and Rx of glucocorticoid-remediable aldosteronism?
The ACTH regulatory element fuses with the aldosterone synthase gene, bringing aldosterone under control of ACTH + increasing production. Rx: Dexamethasone normalises biochemistry but perhaps not BP By suppressing ACTH release
51
Tests if suspecting primary aldosteronism:
1. U+Es, venous blood gas- hypokalaemic alkalosis 2. Plasma Renin- normally low due to dilutional effects of salt + water retention Plasma aldosterone to renin ratio- high aldosterone vs renin Drugs may interfere- diuretics, steroids, antihypertensives, laxatives 3. CT or MRI to localise cause 4. Adrenal vein sampling- identify adenoma
52
How are the common causes of aldosteronism (Conn's, adrenal hyperplasia) managed differently?
Conn's: spironolactone for 4 weeks then laparoscopic adrenalectomy Hyperplasia: medical management- spironolactone, amiloride, eplerenone
53
Causes of secondary hyperaldosteronism?
High renin and high aldosterone Reduced renal perfusion (renin release stimulated by low pressure, lack of salt in DCT or sympathetic input) from: Renal artery stenosis Accelerated hypertension Diuretics, CCF, hepatic failure
54
What is Bartter's syndrome and what U+Es findings would you expect?
Autosomal recessive salt wasting Sodium chloride leak in the loop of Henle via a defective channel Sodium loss > aldosteronism > low K+ and alkalosis PC: polydipsia, polyuria and failure to thrive in childhoos
55
What is a phaeochromocytoma?
Catecholamine-producing tumour Arising from sympathetic paraganglionic cells (chromaffin cells) in the adrenal medulla 10% rule 10% malignant 10% extra-adrenal (by aortic bifurcation) 10% bilateral 10% inheritable (MEN2a, MEN2b, neurofibromatosis, von Hippel Lindau)
56
What is the classic triad of phaeochromocytoma?
1. Episodic headache 2. Sweating 3. Tachycardia
57
Tests for phaeochromocytoma?
3 x 24 hour urine samples- metadrenalines and normetadrenalines Localisation: Abdo CT/MRI or MIBG chromaffin seeking isotope scan
58
Rx of phaeochromocytoma:
a-adrenoreceptor blockade- phenoxybenzamine as unopposed a-stimulation will cause vasoconstriction (b adrenorecptors dilate vessels to skeletal muscle) b-blockers if tachycardic Surgical removal
59
What parts of the adrenal gland make the different hormones?
Medulla- noradrenaline (phaeochromacytoma) Cortex- GFR GFR Miner GA: Glomerulosa- mineralcorticoid Fasciculata- glucocorticoids Reticularis- androgens
60
What is Takotsubo cardiomyopathy?
Stress or catecholamine-induced cardiomyopathy (broken heart syndrome) Sudden chest pain, mimicking an MI ECG shows ST elevation Echo- Apical ballooning during catecholamine surges Can occur with phaeochromocytoma
61
Causes of primary adrenocortical insufficiency (Addison's disease):
Vascular: Waterhouse-Friderichsen's syndrome of bilateral adrenal haemorrhage from meningococcal sepsis where endotoxin activates inflammatory and clotting cascades (DIC) or SLE, antiphospholipid syndrome ``` Infection: TB (commonest cause worldwide), opportunistic HIV (T) Autoimmune: 80% on UK (M) Iatrogenic Neoplasia: mets, lyphoma ```
62
How does Addison's present?
PC: Tired, weak, dizzy, myalgia, arthralgia Depression, psychosis N+V, abdo pain, constipation or diarrhoea EHx: Hands- pigmented palmar creases, vitiligo, pigmented skin Shock- hypotensive, tachycardic, pyrexial, coma
63
Patient has low Na+, high K+, low glucose, high Ca+, low Hb | What needs to be excluded and how?
Low Na+ and high K+ is lack of aldosterone Low glucose may be due to low cortisol So Addison's disease: Short ACTH stimulation test (synACTHen test)- check cortisol levels in response to ACTH, will remain low as no ability to make cortisol. 9am ACTH level (high if primary adrenocortical insufficiency)
64
Test for Addison's?
Primary adrenocortical insufficiency 1. U+E: low Na, high K, high Ca, low glucose 2. Short ACTH synacthen test- cortisol low after ACTH 3. 9am ACTH level- low = secondary cause (ACTH-dependent cause) 4. Plasma renin and aldosterone- measure mineralocorticoid status
65
Which antibody is raised in autoimmune Addison's disease? | Responsible for 80% of Addison's in the UK
21-hydroxylase adrenal autoantibodies
66
Rx of Addison's disease?
Hydrocortisone in 2-3 doses- may cause insomnia if given late Fludrocortisone OD Steroid rules apply- no stopping suddenly, double in illness, extra for exercise, IM if vomiting, have steroid card or bracelet
67
How does secondary adrenal insufficiency differ from Addison's disease (primary adrenal insufficiency)?
Mineralocorticoid production remains intact- U+Es normal ACTH is low rather than high No hyperpigmentation- no excess ACTH Commonly due to suppression of pituitary-adrenal axis from exogenous steroids
68
Which hormones does ACTH stimulate production of?
Cortisol- fasciculata Androgens- reticularis (GFR minerGA) Rarely in glucocorticoid-remediable aldosteronism it can stimulate aldosterone release due to gene fusion
69
What's the difference between Cushing's syndrome and Cushing's disease?
Cushing's syndrome- clinical state produced by chronic glucocorticoid excess and loss of normal feedback mechanisms in the axis. Primarily due to exogenous steroids. Cushing's disease- pituitary adenoma secreting ACTH leads to bilateral adrenal hyperplasia, a specific and rare cause of Cushing's syndrome
70
What are the ACTH dependent and independent causes of Cushing's syndrome?
ACTH dependent: Pituitary adenoma (Cushing's disease) Ectopic ACTH production- small cell lung cancer, carcinoid tumours Ectopic CRF (Corticotrophin Releasing Factor)- medullary and prostate cancers ACTH independent: Oral exogenous steroids Adrenal nodular hyperplasia Adrenal adenoma/cancer Carney complex (pigmented, myxoma, schwannoma, endo tumours) McCune-Albright syndrome (fibrous dysplasia of bone, pigmented)
71
What type of cancer's produce ectopic ACTH and which rarely can produce CRF?
ACTH- small cell lung cancer and carcinoid tumours | CRF- medullary thyroid and prostate cancer
72
How does ectopic ACTH production in Cushing's syndrome cause a hypokalaemic metabolic alkalosis?
Very high cortisol mimics mineralocorticoid activity = hyperaldosteronism So more K+ exchanged for Na+ and more activation of proton ATPase leading to proton excretion
73
How to investigate suspected Cushing's syndrome:
1. Late night cortisol 2. Overnight Dexamethasone suppression test Dex at midnight, serum cortisol at 8am, no suppression 3. 48 hour high dose Dex suppression test (halves cortisol in pituitary adenoma, Cushing's disease) 4. Plasma ACTH= dependent or independent cause
74
How are ACTH dependent causes of Cushing's syndrome investigated differently from independent causes once the ACTH dependency is established?
So after plasma cortisol,overnight dex test, high dose suppression test, ACTH levels ACTH high: Suppressed by high dose dex (pituitary cause) > head MRI Not suppressed > CT chest, abdo, pelvix with contrast ± MRI ACTH low: CT adrenal glands No mass > adrenal vein sampling or adrenal scintigraphy
75
Rx of Cushing's disease or ectopic ACTH production:
Pituitary adenoma secreting ACTH: transphenoidal removal of adenoma Ectopic ACTH production: excision of tumour, ketoconazole and fluconazoe reduce cortisol pre-op if high If ACTH causing psychosis may need cortisol receptor antagonist (mifespristone)
76
Effects of PTH?
``` Secreted in response to low ionised Ca+ Increases osteoclast activity Increases Ca+ reabsorption in the kidney Reduced PO4 reabsorption by kidney Increases active Vit-D3 production ```
77
Causes of primary hyperparathyroidism?
80% parathyroid adenoma 19% hyperplasia 0.5% cancer
78
What can cause a high calcium and high or inappropriately normal PTH?
Primary hyperparathyroidism- adenoma, hyperplasia Thiazides + lithium Familial hypocalciuric hypercalcaemia (check 24hr urine Ca+) Tertiary hyperparathyroidism (autonomous production of PTH after long period of secondary PTHism)
79
Management of primary hyperparathyroidism?
``` Conservative: Increase fluid (prevents stones) Avoid thiazides Ensure good vit D + calcium intake ``` Medical: 2nd post surgery Cinacalcet reduces PTH glands sensitivity to Ca+ Surgical: US or MIBG might isolate a adenoma for removal Or parathyroid gland excision if high Ca+, osteoporosis or renal damage SEs: reccurent laryngeal nerve damage, low Ca+
80
If secondary/tertiary hyperparathyroidism is caused by CKD how will this look different from primary parathyroidism?
Secondary has low Ca and high PTH low Vit D means low Ca absorption in gut and low Ca Primary would have high Ca and high PTH Tertiary has high Ca and very high PTH because glands are acting autonomously without any feedback
81
Which type of cancer rarely produces PTH related peptide?
Squamous cell lung cancers | Breast + renal cell carcinomas
82
Patient has short 4th and 5th metacarpals, low IQ, high PTH and short stature. Cause?
Pseudohypoparathyroidism | Genetic loss of target cell response to PTH
83
Differences between MEN1, MEN2a and MEN2b?
MEN1 - 3P's Parathyroid, Pituitary (prolactinoma or GH), Pancreas (VIPoma, insulinoma) MEN2a - 2P, 1M Parathyroid, Phaeochromocytoma, Medullary thyroid MEN2b- 1P, 2M Phaeochromocytoma, Medullary thyroid, Marfanoid appearance/ mucosa neuroma
84
Name 7 Multiple Endocrine Neoplasia syndromes and their characteristic features:
Autosomal dominant syndromes A with hormone-producing tumours 1. Neurofibromatosis Type 1- cafe au lait spots, skin fold freckling, neurofibromas, Lisch nodules in eyes Type 2- cafe au lait spots, schwannoma causing acoustic neuroma 2. MEN1: Parathyroid, Pancreas (VIPoma, insulinoma etc), Pituitary (prolactinoma, GH-producing) 3. MEN2a: Parathyroid, phaeochromocytoma, medullary thyroid 4. EN2b: Phaeochromocytoma, medullary thyroid, Marfainoid 5. Von Hippel Lindau: renal cysts, phaeo, cerebellar haemangioma 6. Peutz Jeghers: lip, mucosa, hand + feet freckling, GI polyps 7. Carney complex: pigmentation, myxoma, schwannoma, adrenal and pituitary tumours
85
In MEN1 syndrome, what types of pancreatic hormonal tumours may arise and their symptoms?
Gastrinoma (Zollinger Ellison): multiple + distal peptic ulcers, chronic diarrhoea as pancreatic enzymes are inactivated Insulinoma: hypoglycaemia- faint, sweaty, tremor, palpitations Somatostatinoma: DM, steatorrhoea, gallstones VIPoma: diarrhoea and low K+, acidosis, high Ca+, low Mg+ Glucagonoma: migrating rash, glossitis, anaemia, weight loss
86
Symptoms of hypothyroidism
Tired, sleepy, lethargic, depressed, reduced memory, dementia Weight gain, constipation Myalgia, cramps, neuropathy, myopathy, weakness Menorrhagia, hoarse voice
87
Causes of hypothyroidism:
Primary autoimmune: Atrophic Hashimoto's- goitre from lymphocyte infiltration Iodine deficiency Iatrogenic- radioiodine or thyroidectomy Drugs- Amiodarone, lithium, antithyroid drugs Post viral- Subacute de Quervain's Secondary- very rare, pituitary insufficiency
88
Rx of hypothyroidism, and things to watch out for with treatment:
Levothyroxine Half life 7ds, so wait to check effects when changing dose Susceptible to more metabolism when enzyme inducers given
89
What is subacute hypothyroidism and how is it managed?
TSH raised, T4 normal Risk of progression to hypothyroidism Can try a trial of medication if TSH >4 to see if patient functions better
90
Signs specific to Graves disease:
Eye disease- exopthalmos, opthalmoplegia Pretibial myxoedema Thyoid acropachy Bruit, mild neutropenia
91
What type of antibodies are associated with Graves disease?
TSH R antibody (Graves) Thyroid peroxidase antibody (Graves or Hashimoto's) Thyroglobulin antibody (Hashimoto's or thyroid cancer)
92
If someone has hyperthyroidism and you give them contrast for a CT scan, what happens?
Thyroid storm
93
Causes of hyperthyroidism and how they differ on isotope scan?
Graves- autoantibodies, global uptake of isotope Toxic multinodular goitre- in elderly or iodine deficient, focal nodules Toxic adenoma- hot nodule, rest supressed Ectopic thyroid tissue- follicular thyroid cancer or ovarian Iodine excess, amiodarone, levothyroxine Subacute de Quervain's- low isotope uptake (NSAIDs help) Post-partum
94
Management of hyperthyroidism:
Propranolol for symptoms Carbimazole- either titrated up or block completely + give thyroxine For 1-1.5 years, then withdraw. Thyroidectomy or radio iodine (CI: pregnancy) if relapse.
95
Main risk factor for Graves eye disease?
Smoking
96
Symptoms of Graves eye disease?
Grittiness, tear production Discomfort, photophobia Diplopia, reduced acuity, afferent pupillary defect* *optic nerve compression eek! Exopthalmos = appearance of protruding eye, proptosis = eye extends beyond orbit
97
Management of Graves eye disease
Conservative: if mild, artificial tears, sunglasses, elevate bed at night, Fresnel prism for diplopia Medical: if severe, high dose steroids Surgical: if sight threatening, decompression or cosmetic
98
A painful goitre amounts to what typically:
Subacute De Quervain's thyroiditis (viral)
99
What is sick euthyroidism?
TSH and T4 all low Following a systemic illness, TFTs may become deranged temporarily If repeated when recovered, should not see this
100
What test can you do if suspecting self-induced hyperthyroidism in a patient? (Administering levothyroxine)
Thyroglobulin- the thyroid protein precursor to T4 will be low as endogenous T4 production is suppressed
101
Which patients should be screened for thyroid abnormality?
``` AF Hyperlipidaemia DM, Addison's disease Type 1 DM + pregnant Down's, Turner's syndrome ```
102
When is surgery warranted for a thyroid problem?
Refractory hyperthyroidism (have withdrawn carbimazole after 1.5 years and still hyperthyroid) Nodule is too big >3cm or compression Rapid growth Dominant nodule on scintigraphy, hypoechoic nodule
103
Causes of hypoglycaemia:
EXPLAIN EXogenous drugs- insulin, oral hypoglycaemics Alcohol, ACEi, aspirin poisoning, bblockers, insulin (body builders) Pituitary insufficiency Liver failure Addison's disease Islet cell tumours- insulinoma, anti-insulin R abs in Hodgkins Non-pancreatic neoplasms Post-prandial hypoglycaemia: After gastric or bariatric surgery IHx: prolonged OGTT
104
Tests if a patient has hypoglycaemia?
Blood glucose- laboratory (monitors may not be reliable at low values) Insulin level C peptide- waste product of endogenous insulin production Plasma ketones
105
What causes hypoglycaemia, low insulin and no excess ketones?
Rarely Anti-insulin receptor antibodies (in Hodgkin's lymphoma) Non-pancreatic neoplasms- fibrosarcoma, secreting an peptide downstream from insulin with a similar effect like insulin growth factor
106
A patient has hypoglycaemia, how does the level of insulin determine the likely cause?
High insulin: Insulinoma, sulphonylurea, insulin injection Low insulin, high ketones: Alcohol, pituitary insufficiency, Addison's disease
107
Patient has had a gastric bypass and has been found to be hypoglycaemic after meals, what specific test do they require?
Prolonged oral glucose tolerance test lasting 5 hours
108
Rx of hypoglycaemia?
1. Sugar or long-acting carb if possible 2a. 200mL glucose 10% IV (less vein damage than 50% glucose) 2b. Glucagon IM in no IV access
109
What are Whipple's triad of symptoms for fasting hypoglycaemia:
Occurs in insulinomas (sporadic or part of MEN1) 1. Symptoms associated with fasting or exercise 2. Recorded hypoglycaemia with symptoms 3. Symptoms relieved with glucose
110
Different tests if suspecting insulinoma?
Screening: Insulin level and glucose level during a fast Suppressing: IV insulin + measure C-peptide Normally exogenous peptide suppresses C peptide production Imaging: CT/MRI
111
Which signs distinguish ischaemia from peripheral neuropathy on the foot exam?
Ischaemia: critical toes (ulcers, gangrene), absent dorsalis pedis Peripheral neuropathy: injury or infection over pressure points (like metatarsal head) NB: most patients have both
112
Signs of peripheral neuropathy in the diabetic foot:
Inspect: Charcot foot- absent pes cavus, claw toes, loss of transverse arch, rocker bottom sole Absent ankle jerks Reduced sensation in a stocking distribution
113
Points to educate someone with a diabetic/ischaemic foot on:
1. Daily foot inspection 2. Good shoes- soft leather, increased depth, no barefoot walking, cushioning insoles 3. Regular chiropody- remove calluses 4. Fungal infection treatment 5. Surgery referral potentially
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What are the 4 things to examine or investigate with a diabetic foot ulcer?
Assess degree of: 1. Neuropathy- clinically 2. Ischaemia- clinically, doppler ± angiography 3. Bony deformity(Charcot joint)- clinically + xray 4. Infection- swabs, blood culture, ulcer probe (depth) + xray (osteomyelitis)
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Rx of diabetic neuropathy of the feet
Bed rest to relieve high pressure areas Therapeutic shoes Regular chiropody Abs for infection- benzylpenicillin, flucloxacillin, metronidazole Considerations for surgery
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What are the 4 types of neuropathy someone with diabetes might get?
1. Peripheral sensory neuropathy- glove + stocking 2. Mononeuritis multiplex- if sudden or severe, immunosupression can be tried 3. Amyotrophy- painful wasting of quadraceps 4. Autonomic- postural BP drop, gastroparesis, urine retention, ED
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How should gastroparesis be proved in a diabetic patient who is experiencing early satiety, post-prandial N+V and bloating?
99-technetium labelled meal Rx: antiemetics, erythromycin or gastric pacing
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Complications of diabetes:
Macrovascular- MI, stroke, peripheral arterial disease Statin advised + clopidogrel if PAD Microvascular- nephropathy, neuropathy, retinopathy ACEi i microproteinuria
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Stages of diabetic retinopathy:
Nonproliferative retinopathy: mild, moderate and severe Mild- dots + blots Moderate- dots, blots, hard exudates Severe- blots, cotton wool spots, venous beading + loops Proliferative retinopathy: New vessel formation (floaters, visual loss) Maculopathy: Exudate (from vessel leaks) or retinal thickening within an optic disc
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Rx of maculopathy?
Sudden vision loss- Intravitreal steroids Laser photo-coagulation (to destroy peripheral ischaemic vessels releasing anti-VEGF) Anti- angiogenic agents
121
What is the stepwise approach to oral glycaemic agents in T2DM?
HbA1c >48: lifestyle measures HbA1c >48: metformin >58: meformin + other drug* (Aim <53) >58: metformin + 2 other drugs (often 1 sulfonylurea) or insulin *sulfonylurea, gliptin, SGLT2i, pioglitazone
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Under what circumstances is a GLP-2 mimetic indicated? (Exenatide)
If triple therapy of metformin + 2 other drugs is not tolerated AND BMI >35 = metformin + sulfonylurea + GLP1 mimetic
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What is needed to diagnose diabetes?
``` Symptoms + fasting glucose >6.9 Symptoms + random glucose >11 2 occasions of abnormal glucose HbA1c >48 1 abnormal glucose + abnormal OGTT (>11 at 2 hours) ```
124
Which HLA groups is diabetes mellitus type 2 associated with?
HLA DR3 (3 little pigs and a straw shack)- HLA DR4- rheum for dad and mum (DM)
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What are the untypical forms of type 1 and 2 DM?
Latent autoimmune diabetes of adults- T1DM onsetting later in life Mature onset diabetes of the young- T2DM onsetting earlier in life (autosomal D)
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Features of metabolic syndrome:
Central obesity (waist circumference or BMI >30) + 2 of: ``` 1. Hypertension >130/85 2. Insulin resistance DM or fasting glucose >5.5 3. Low HDL levels 4. Hypertriglyceridaemia >1.6 mmol ```
127
How does tubular dysfunction cause a difference in U+Es results than low eGFR?
Tubular dysfunction: low K+, low urate, low phosphate, high H+ May be polyuric with all sorts in the urine Low eGFR: high K+, high urate, high phosphate, low H+ May be oliguric
128
What pattern of U+Es do thiazides and loop diuretics cause?
Low Na+, low K+, high bicarbonate Thiazide- high Ca in blood (the-HIGH-azide) Loop diuretics- low Ca (Lowoop)
129
How quickly can potassium be given in a peripheral line?
20mmol an hour But 40mmol per bag max
130
how does ma differ depending on whether someone has osteopenia or osteoporosis?
Osteopenia (T score from -2.5 to -1): lifestyle advice Stop smoking, reduce alcohol Weight bearing exercise, tai chi, calcium rich diet, OT input at home Osteoporosis (T score below -2): lifestyle and Rx
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Causes of osteomalacia:
Vit D deficiency or resistance (inheritable) Renal osteodystrophy Liver failure- needed to convert Vit D also Drug induced- anticonvulsants
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What is Paget's disease and the complications of it?
Increased numbers of osteoclasts and osteoblasts + remodelling causing bone enlargement + deformity. Asymptomatic 70% Bony pain + deformity > pathological fractures, osteoarthritis High Ca Nerve compression from bone overgrowth (deafness) High output CCF Osteosarcoma <1%
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Rx of Paget's disease:
Analgesia | Bisphosphonates
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Commonest type of porphyria and how it manifests:
Acute intermittent porphyria- autosomal dominant Neurovisceral symptoms: Abdo pain, vomiting, constipation, fever, WCC Peripheral neuropathy, seizures, psychosis High BP + HR, low BP
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How do acute and chronic porphyrias present differently?
Acute: neurovisceral symptoms with photosensitivity in the less common type (variegate prophyria) Chronic: cutaneous photosensitivity alone- may have increased facial hair or hyperpigmentation (prophyria cutanea tarda, erythropoeitic protoporphyria)
136
What is the inheritance and cause of primary hyperlipidaemia?
Autosomal dominant Mutations in LDL receptors impairs exchange of LDLs Heterozygotes- cardiovascular disease
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What are the four types of primary hypertriglyceridaemia?
1. Familial hypertriglyceridaemia Xantomata, high VLDLs 2. Familial dysbetalipoproteinemia Elevated intermediate DLs + chylomicrons 3. Lipoprotein lipase deficiency Chylomicron metabolism 4. Apo CII deficiency Needed to activate lipoprotein lipase
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What are secondary causes of elevated LDLs?
Hypothyroidism Liver disease Nephrotic syndrome Thiazides, glucocorticoids, ciclosporin
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What are secondary causes of elevated triglycerides?
Obesity, diabetes, proegesterone, acute hepatitis Alcohol, oestrogens, antifungals
140
What are eruptive xanthomata and what do they occur in?
Itchy crops of lipid nodules found in primary hypertriglyceridaemia
141
MEN2A+ 2B patients with medullary thyroid cancer have what gene mutation?
RET gene mutation- gain of function