Endocrinology

Question 1

Electrolyte abnormality in alcoholics.

Answer 1

Remember there are 2 hypos associated with alcoholism.
Hypoglycemia and hypokalaemia.

Vomiting → loss of K in the vomitus AND loss of hydrochloridric acid → metabolic alkalosis → activation of RAAS mechanism → loss of K in urine.

Many patients with K deficiency are also magnesium deficient.

Question 2

A 34 YO female with milk discharge, she is nulliparous and has not had any menstruation in the last 6 months.

What hormone is affected?

Answer 2

Hyperprolactinaemia causes a syndrome of galactorrhoea and amenorrhoea.

Question 3

Laboratory finding that leads to diabetes insipidus diagnosis.

Answer 3

After giving vasopressin there will be an increase in urine osmolality = Central Diabetes Insipidus.

If no changes after vasopressin = Nephrogenic Diabetes Insipidus.

Question 4

Female with hx of breast cancer, depression (takes fluoxetine), drowsiness and excessive thirst.

Answer 4

Hypercalcemia!

Drowsiness and increased thirst with Hx of breast cancer should spark hypercalcemia as a differential.

Breast cancer usually causes bone metastases, this causes hypercalcemia.

Increased thirst is a feature of hypercalcemia NOT hyponatremia.

Also, depression worsens with hypercalcemia.

Question 5

46 yo female, lives in UK, complains of weight gain, constipation and sensitivity to cold. She has a pulse of 50, regular.

Answer 5

Hypothyroidism.

Most common cause → nutritional deficiency

*But on developed countries like UK it is AUTOIMMUNE.

Question 6

Addison’s disease clinical features

Answer 6

In developed countries it is autoimmune

Rest of the world → tuberculosis
(Other causes include metastasis, CMV and adrenal hemorrhage)

Associated with DM, thyroid disorders and vitiligo.

Acutely it presents as an Addisonian crisis.

Chronically pxs present with insidious and mild symptoms like

• Fatigue and weakness
• Salt cravings (primary insufficiency)
• Hyperpigmentation (primary insufficiency)
• Postural hypotension
• Abdominal pain, nausea, vomiting, anorexia and weight loss.
• Syncope and dizziness
• Personality changes, irritability and confusion.

Question 7

Addison’s disease investigations.

Electrolytes?

How is the test done?

How do I exclude Addison’s disease in that test?

Plasma renin and aldosterone will be increased or decreased?

Will I find antibodies?

Should I do another test if there are no antibodies?

Answer 7

Low 9am cortisol

Hyponatremia and hyperkalaemia

ACTH stimulation test (Synacthen test)
→ IM ACTH administered and cortisol levels measured after.
Cortisol of >550 nmol/L excludes Addison’s disease.

ACTH ↑

↑ Plasma renin and ↓ plasma aldosterone.

21 hydroxylase adrenal antibodies.

CT abdomen if antibodies are negative.

Question 8

What endocrinological disease should I suspect in a patient with Meningitis?

Answer 8

SIADH (syndrome of inappropriate antidiuretic hormone secretion)

Results in euvolaemic hyponatraemia.

Hypernatremia is often seen in Diabetes Insipidus which is not the case.

Question 9

A man with prostate cancer has confusion, thirst, lower back pain and abdominal pain. What is the most likely diagnosis?
What would be the most likely finding in the ECG?
What is the single most appropriate investigation?

Answer 9

Hypercalcemia

Shortening of QT interval

The most appropriate investigation would be a serum calcium.
There are no symptoms of tingling or numbness in the legs so there is no rush to perform a MRI to investigate malignant spinal cord compression.

Question 10

Hypercalcemia clinical features

Answer 10

Decreased mental activity like lethargy, confusion and depression (groans)

Decreased bowel activity = constipation (moans)

Polyuria and polydipsia caused by nephrogenic diabetes insipidus. Calcium precipitates in the kidney resulting in kidney stones an nephrolitiasis. (stones)

Bone pain is only seen when it is hyperparathyroidism which is causing hypercalcaemia (bones)

short QT

Question 11

Causes of Cushing syndrome (2 groups)

Answer 11

ACTH (adrenocorticotropic hormone) dependent disease
Excessive ACTH from pituitary (Cushing’s disease)
Ectopic ACTH producing tumours like small cell lung cancer and carcinoid tumours.

Non ACTH dependent
Adrenal adenomas
Adrenal carcinomas
Excess glucocorticoid administration (main cause)

Question 12

Clinical features of Cushing’s syndrome

Answer 12

Round face
Acne and hirsutism
Weight gain (truncal obesity, buffalo lump)
Skin may look thin and fragile
Purple striae on abdomen, breasts, thighs, axilae
Proximal muscle weakens
Depression and insomnia
Growth arrest in children.

Question 13

Cushing’s syndrome outpatient tests

Answer 13

24 hour urinary free cortisol (as outpatient screening tool)

Overnight dexamethasone suppression test
Administration of 1mg dexamethasone midnight followed by serum cortisol measurement at 9am
Cortisol <50nmol/L makes Cushing’s unlikely (best to establish Cushing’s syndrome diagnosis)

Question 14

Cushing’s syndrome inpatient tests

Answer 14

ACTH levels (once the diagnosis of Cushing’s syndrome is confirmed. It differentiates between ACTH dependent and independent aetiologies.)

High-dose dexamethasone suppression test: Differentiates between a pituitary adenoma and an ectopic source. The output of a pituitary adenoma will suppress with high-dose dexamethasone (cortisol suppressed). The output of an ectopic source will not suppress (cortisol not suppressed)

Question 15

ECG changes in hyperkalaemia

Answer 15

Tall-tented T waves
Small P waves
Widened QRS leading to a sinusoidal pattern and asystole.

Question 16

Severity of hyperkalaemia

Answer 16

Mild 5.5 to 5.9 mmol/L

Modertae 6.0 to 6.4 mmol/L

Severe ≥6.5 mmol/L

Question 17

Causes of hyperkalaemia

Answer 17

Acute renal failure

Potassium-sparing diuretics, ACEi, ARB, spironolactone

Metabolic acidosis

Addison’s

Question 18

Management of hyperkalaemia

Answer 18

Stop drugs that cause hyperkalaemia

ECG changes > IV calcium (chloride or gluconate)
Used to stabilise cardiac membrane
ECG changes are more accurate than plasma K levels

If severe hyperkalaemia and short-term shift in K extracellular to intracellular fluid compartment is needed > Insulin and dextrose infusion.

REMEMBER ≥ 6.5 use Calcium gluconate

6.0 to 6.4 AND ECG changes USE calcium gluconate

Question 19

Diabetes insipidus main forms and clinical features.

Answer 19

Cranial DI: decreased secretion of ADH reduces the ability to concentrate urine and so causes polyuria and polydipsia.

Nephrogenic DI: decreased ability to concentrate urine because resistance to ADH in the kidney

Marked polyuria (sometimes more than 3L a day)

Polydipsia and chronic thirst

Nocturia

Question 20

Most appropriate initial test for a suspected diabetes insipidus

Answer 20

Urine osmolality

If the osmolality is >800mOsm/kg then we proceed further by getting plasma osmolality and performing a fluid deprivation test.

The fluid deprivation test is to differentiate between central or nephrogenic diabetes insipidus.

Question 21

Difference in fluid deprivation test between central DI and nephrogenic DI

Answer 21

Central DI the urine volume decreases and urine osmolality increases after administering desmopressin.

Nephrogenic DI: there is no change after administering desmopressin

Central DI after fluid deprivation <300
after desmopressin >800

Nephrogenic DI after fluid deprivation <300
After desmopressin <300

Question 22

Primary hypothyroidism causes

Answer 22

Autoimmune hypothyroidism (Hashimoto’s)

Iatrogenic: radioiodine tx, surgery, radiotherapy to the neck

Drugs: amiodarone, contrast media, iodides, lithium and antithyroid medication

Congenital defects (absence of thyroid gland)

Question 23

Secondary hypothyroidism causes

Answer 23

Isolated TSH deficiency

Hypopituitarism: neoplasm, infiltrative, infection and radiotherapy

Hypothalamic disorders: neoplasms and trauma

Question 24

Hypothyroidism signs and symptoms

Answer 24

Tiredness, lethargy, intolerance to cold

Dry skin and hair loss

Slowing of intellectual activity (poor memory and difficulty concentrating)

Constipation

Decreased appetite with weight gain

Menorrhagia and later oligomenorrhoea or amenorrhoea.

Dry coarse skin, hair loss and cold peripheries.

Puffy face, hands and feet (myxoedema)

Bradycardia

(In autoimmune hypothyroidism, pxs may have features of other autoimmune diseases like vitiligo, pernicious anaemia, Addison’s and DM)

Question 25

TSH and free T4 in Graves' disease and Subacute thyroiditis (De Quervain's thyroiditis)

Answer 25

TSH is low Free T4 is high In Grave's radioactive iodine uptake test is increased In De Quervain's radioactive iodine uptake test is decreased (usually followed by URTI)

Question 26

``` TSH levels and free T4 in Primary Secondary Sick euthyroid syndrome Subclinical hypothyroidism Poor compliance with thyroxine medication. ```

Answer 26

Primary TSH high and free T4 low Secondary TSH low and Free T4 low Sick euthyroid syndrome TSH low and Free T4 low Subclinical hypothyroidism TSH high free T4 normal Poor compliance with thyroxine medication TSH high and free T4 normal.

Question 27

23 YO female with lethargy, dry skin on her legs. TSH 9.8 mU/L (0.5-5.7mU/L) and free thyroxine (T4) 11pmol/L (9-18) The test is repeated 3 months later. TSH 8.8 and T4 15. She has no goitre palpable on examination, and she is trying to conceive. What would be the most appropriate next step?

Answer 27

Consider starting levothyroxine. She has subclinical hypothyroidism. (High TSH and low T4) She is symptomatic, below 65 and is trying to conceive so she would benefit from levothyroxine. (If >65YO no tx required, tx may cause AFib) It is managed in primary care. T3 level is no required unless T4 levels are abnormal.

Question 28

Best test and management for phaeochromocytoma

Answer 28

24 hour urinary collection of metanephrines (S95% vs 86% of catecholamines) ``` Surgical resection with BP stabilization Alpha blocker (phenoxybenzamine) 7-10 days BEFORE surgery to allow for expansion of blood volume. ``` Beta blocker (propranolol) after alpha blocker. If done incorrectly unopposed alpha stimulation can precipitate a hypertensive crisis

Question 29

Hyperthyroidism clinical features

Answer 29

``` Hyperactivity, irritability Insomnia Heat intolerance Sweating Palpitations Fatigue Weight loss Increased appetite Pruritus Increase stool frequency Oligomenorrhoea or amenorrhoea Sinus tachycardia, AFib Fine tremor ```

Question 30

Thyroid storm and clinical features

Answer 30

An acute and exaggerated presentation of hyperthyroidism most commonly precipitated by treatment with radioiodine, thyroid surgery, myocardial infarction and infection. ``` Classic features of hyperthyroidism Altered mental status Elevated temperature Tachycardia AFib Diarrhoea and vomiting Other features include acute abdomen and heart failure ```

Question 31

Investigation and treatment of thyroid storm

Answer 31

``` TSH, free T3 and T4 Uptake scan (Tc-99m) aids confirmation ``` Tx: ALWAYS ABC first Seek help from endocrinology team 3 domains of tx: 1. Counteracting the peripheral effects of thyroid hormone. Beta blockade > propranolol if no contraindication Once adequately beta blocked > Digoxin to control the heart rate 2. Inhibiting thyroid hormone synthesis Antithyroid drugs > Propylthiouracil (PTU is preferred over carbimazole in emergencies as it prevents peripheral T4 to T3 conversion. Carbimazole works by reducing the production of T3 and T4 which has a slower clinical effect) Lugol’s iodine following PTU (Lugol’s will prevent the release of hormone) Prevent peripheral conversion of T4 to T3 > hydrocortisone/dexamethasone 3. Tx systemic complications If the cause is infection > IV co-amoxiclav Elevated temperature > Paracetamol The dose of antithyroid drugs can be adjusted in 5 days. Stop propranolol and iodine in 10 days. In dire circumstances, thyroidectomy may be indicated if there is no improvement in 24 hours.

Question 32

Px with DM2 that takes gliclazide (sulfonylurea) that is programmed for an endoscopy. What is the most appropriate advice regarding his diabetic management?

Answer 32

Remember sulfonylureas are associated with hypoglycemia in the fasted state. An endoscopy is a minor procedure, so sulfonylureas should ne omitted on the day of the procedure until the px can eat and drink again.

Question 33

DM perioperative management

Answer 33

Sulfonylureas (glibenclamide and gliclazide) Only omit the day of the surgery and restart once eating and drinking Metformin (including Glucophage SR) Take as normal Unless surgery with contrast dye, needs to be stopped 2 days before. Can be restarted 2 days after contrast dye. Pioglitazone Take as normal DPP IV inhibitor (gliptins) Take as normal Long acting GLP-1 analogue (exenatide) take as normal. REMEMBER glycemia should be checked regularly before, during and after surgery. If at any point glucose level >11mmol/L consider starting an insulin infusion IV.

Question 34

Hypercalcaemia aetiology

Answer 34

Primary hyperparathyroidism> main cause of hypercalcaemia but mainly mild = asymptomatic pxs. Malignancy > Multiple myeloma, production of PTH like molecule (by Squamous cell carcinoma of the lung) this is a common cause that requires hospital admission Familial hypocalciuric hypercalcaemia Immobilization Sarcoidosis Remember moans, groans, stones and bones (Lethargy, confusion, depression AND constipation AND kidney stones/ nephrolithiasis AND only in hyperparathyroidism bone pain AND short QT

Question 35

Hypercalcamia management

Answer 35

The initial management of severe hypercalcaemia is rehydration (typically 3-4L/day). Increasing circulating volume helps to increase the urinary output of calcium Following rehydration bisphosphonates may be administered IV Calcitonin> fewer side effects than bisphosphonates but less effective in reducing hypercalcaemia. Steroids > If sarcoidosis Cinacalcet hydrochloride is a calcimimetic agent that effectively reduces parathyroid levels in px with secondary hyperparathyroidism. Haemodialysis or peritoneal dialysis may be relevant in patients with severe hypercalcaemia secondary to renal failure. Furosemide has limited role > It is occasionally used where there is fluid overload but it does not reduce serum calcium.

Question 36

DM2 diagnosis symptomatic vs asymptomatic

Answer 36

If symptomatic random glucose >11.1mmol/L or fasting >7mmol/L If asymptomatic 2 fasting venous plasma glucose samples in the abnormal range are recommended for the Dx (>7mmol/L) Oral glucose tolerance test is no longer recommended

Question 37

DKA precipitating factors and Dx

Answer 37

``` Infection Missed insulin dose Cardiovascular disease (stroke or MI) ``` Dx: capillary blood glucose >11mmol/L or known DM Capillary ketones > 3mmol/L or urine ketones ++ or more Blood gas > pH less than 7.3 and/or bicarbonate less than 15mmol/L

Question 38

DKA management

Answer 38

ABC! Pxs may have lost up to 5 liters! If SBP <90mmHg then 1L of saline 0.9% in 10-15 mins If SBP >90mmHg then 1L of saline 0.9% over 1 hour Following saline infusion then insulin therapy is added (>1 hour after IV saline has started, if added earlier then ↑ risk of cerebral oeadema) If plasma glucose <12mmol/L then replace normal saline with dextrose 5% to prevent over-rapid correction of blood glucose and hypoglycaemia Hypokalaemia may need to be corrected with KCl (40mmol/L KCl can be added after the 1st L of fluid is administered if K is 3.5-5.5mmol) REMEMBER 0.9% saline FIRST Followed by insulin and KCl If glucose falls <14mmol/L commence dextrose 10% ALONGSIDE saline

Question 39

How can someone differentiate between Cushing's disease and Ectopic ACTH-producing tumours?

Answer 39

Remember 24h urinary free cortisol as outpatient screening tool Overnight dexamethasone suppression test to diagnose Cushing's syndrome ACTH levels differentiate between ACTH dependent aetiologies and independent. (small cell lung cancer and Cushing's disease vs. Adrenal adenoma/carcinoma) ***High dose dexamethasone suppression test is used to differentiate between Cushing's disease and Ectopic ACTH-producing tumours A pituitary adenoma is semi-autonomous so a low-dose dexamethasone test will not suppress it but a high dose will. (bilateral adrenal hyperplasia= hyperactivity of BOTH adrenals) An ectopic ACTH producing tumour will not respond as it is fully autonomous (unilateral adrenal hyperplasia)

Question 40

What is the most likely visual abnormality associated with pituitary tumour?

Answer 40

Bitemporal hemianopia by tumour pressing optic chiasma.

Question 41

Hyperprolactinaemia patophysiology

Answer 41

An excess of prolactin secretion, may cause syndrome of gallactorrhoea-amenorrhoea. The amenorrhoea is caused by inhibition of hypothalamic release of luteinizing hormone releasing hormone (LHRH) with a decrease in LH and follicle-stimulating hormone (FSH) secretion. Prolactin inhibits the LH surge that causes ovulation. Gynecomastia and especially galactorrhoea in men is rare.

Question 42

Hyperprolactinaemia causes

Answer 42

Physiologic (pregnancy, nipple stimulation/suckling, stress) Pituitary tumours (prolactinomas) Hypothalamic diseases > mass compressing like craniopharyngioma and meningioma Hyperprolactinaemia as a result of decreased inhibitory action of dopamine (antipsychotic drugs like Haloperidol; clozapine and olanzapine also cause hyperprolactinaemia but not on standard doses) Hypothyroidism> thyrotropin-releasing hormone (TRH) increases prolactin

Question 43

Clinical features of hyperprolactinaemia

Answer 43

Galactorrhoea usually in women (men and premenopausal women rarely get galactorrhoea) Menstrual abnormalities (amenorrhoea or oligomenorrhoea) Disturbed gonadal function in men (erectile disfunction, decreased libido, gynecomastia in men, reduced fertility) Mass effects> headaches and visual field defects (uni or bitemporal defects, bitemporal is more common) Hypotuitarism

Question 44

Dx of hyperprolactinaemia

Answer 44

Always exclude pregnancy, lactation, hypothyroidism and medications before starting work-up Serum prolactin < 2,000mU/L is suggestive of a tumour (microprolactinoma or non-functioning macroadenoma) >4,000mU/L is diagnostic of macroprolactinoma Imaging MRI

Question 45

Thyroid lump work-up

Answer 45

Ultrasound as they are extremely sensitive for thyroid nodules. Followed by Fine-needle aspiration cytology (FNAC) Then Radionuclide imaging and MRI if thyroid carcinoma. **Most appropriate in lumps >2cm FNAC** **initial= ultrasound**

Question 46

38YO female stopped taking combined oral contraceptive pills 6 months ago, she has been amenorrhoeic since then. She does not take any regular medications. Her pregnancy test is negative. She does not suffer from any headaches or visual changes. BMI 24. FSH 25IU/L (normal Luteal 2-8, Ovulation 5-25, postmenopause >25) LH 16 IU/L (normal luteal 3-16, ovulation 16-84, postmenopause 17-75UI/L) Prolactin 540mU/L (normal <440mU/L or <25ng/mL) LFT, RFT and TFT are normal. Dx?

Answer 46

Post pill amenorrhoea It is a biochemical result of a normal (or low normal) FSH and LH and a normal to mildly raised prolactin. Here FSH and LH are normal (FSH upper limit) The distractor is premature ovarian failure. FSH would normally be >25IU/L. 2 values of >25UI/L 4 weeks apart are required for the diagnosis (Guidelines of the ESHRE 2015) Hypothalamic amenorrhoea can be considered but the BMI would be below 17kg/m2. (The results would be low GnRH, FSH, LH and oestrogen levels)

Question 47

Safety issues of biguanides and sulphonylureas

Answer 47

``` Biguanides No risk of hypoglycemia Weight loss Cardiovascular benefits If eGFR < reduce dose If eGFR <30 discontinue ``` Sulphonylureas Risk of hypoglycemia Weight gain If renal impairment ↑ risk of hypoglycemia

Question 48

Safety issues of Gliptins DPP4 inhibitors and pioglitazones

Answer 48

DPP4 Rare hypoglycemia Neutral weight Risk of pancreatitis and HF ``` Pioglitazones Rare hypoglycemia Weight gain Bladder cancer concerns (contraindicated, asses risk for bladder cancer) Contraindicated in HF Fractures in women ```

Question 49

Safety issues of repaglinide and SGLT-2 inhibitors (gliflozins)

Answer 49

Repaglinide Risk of hypoglycemia Weight gain Avoid in liver disease SGLT-2 Rare hypoglycemia Weight loss Life threatening DKA at only moderately raised blood sugars (<14mmol/L)

Question 50

GLP-1 agonists incretin mimetics safety issues

Answer 50

Rare hypoglycemia Weight loss Concerns about breast cancer NICE has strict criteria for the use of GLP-1 agonist (enormous cost)

Question 51

DM2 medications that may cause weight loss

Answer 51

Biguanides (metformin) SGLT-2 (gliflozins) GLP-1 agonists (incretin mimetics)

Question 52

DM2 medications that cause weight gain

Answer 52

Sulphonylureas (glyclazide) Pioglitazone Repaglinide

Question 53

DM2 medications that cause hypoglycemia

Answer 53

Sulphonylureas (metformin) Repaglinide ``` Rare DPP4i (gliptins) Pioglitazone SGLT-2i (gliflozins) GLP-1 agonist (incretin mimetics) ```

Question 54

DM2 medication contraindicated in HF

Answer 54

Pioglitazone DPP4i (gliptins) Metformin has cardiovascular benefits

Question 55

What should be done with metformin with a px with eGFR of 42?

Answer 55

Reduce dose! If eGFR <30 then discontinue.

Question 56

DM2 medications contraindicated in obese with low eGFR and HF

Answer 56

Biguanides (metformin) because of eGFR below 30 Sulfonylurea because of weight gain and increased risk of hypoglycemia secondary to renal impairment SGLT-2i because of renal impairment Pioglitazone because of weight gain and HF ``` DM2 medications that can be used in eGFR <30 RIP Repaglinide Inagliptin (Lina but with lower L) Pioglitazone ``` In this case the best medication would be insulin.

Question 57

Hypertension associated with hypokalaemia, refractory hypertension (3 or more drugs), and hypertension before 40YO. With or without hypokalaemia, metabolic alkalosis, normal sodium or upper limit, weakness, headaches and lethargy.

Answer 57

Conn's syndrome! (Hypernatraemia, hypertension and hypokalaemia) Tx with aldosterone antagonists (spironolactone) prior to adrenalectomy. Different from Addison's Drop in aldosterone > drop in sodium > drop in BP (postural) Drop in weight Drop in energy Only K is raised.

Question 58

Hypothalamic amenorrhoea

Answer 58

Due to chronic illness like being significantly underweight (anorexia nervosa). Low gonadotropins and low oestradiol with clinical picture of excessive exercise, low weight or stress.

Question 59

Subacute thyroiditis best medication. | De Quervain's thyroiditis

Answer 59

Propranolol. They refer hyperthyroidism symptoms and high T4 and low TSH is seen. ***A decrease in radionuclide uptake is seen in subacute thyroiditis. It is viral in origin and may have a recent upper respiratory tract infection. (This can be omitted in stems) Tx aims to relieve symptoms> propranolol to reduce HR and palpitations. Carbimazole and propylthiouracil are not indicated as subacute thyroiditis is transient.

Question 60

Osteomalacia common causes and clinical features.

Answer 60

Normal bony tissue but decreased mineral content Rickets the epiphysis has not fused (in younger people) Vit D deficiency (malabsorption, lack of sunlight, diet) Renal failure Drug induced (anticonvulsants) ``` Features Bone pain Fractures Muscle tenderness Proximal myopathy. ``` Slight increase in ALP (in Vit D deficiency osteomalacia)

Question 61

Subclinical hypothyroidism management

Answer 61

TSH high with T4 normal. Must be repeated at 3 months. If asymptomatic just reassure. If symptomatic consider levothyroxine and TFT should be checked every 2 to 3 years.

Question 62

Features of congenital hypothyroidism.

Answer 62

``` Hoarseness of voice Large fontanelles Macroglosia Jaundice Umbilical hernia Poor feeding. ``` In the UK congenital hypothyroidism is picked up on screening (heel prick test). If congenital hypothyroidism is picked then further tests are done and levothyroxine is started.

Question 63

Osteoporosis treatment.

Answer 63

Biphosphonates (alendronate or risedronate as 1st line) Calcium supplements are only considered if the calcium intake is inadequate (<700mg/day SIGN and <1000mg/day NICE) Hormone replacement therapy (HRT) should not be considered as 1st line management due to its adverse effects (breast cancer, venous thromboembolism, coronary disease and stroke) Raloxifene is a selective oestrogen receptor modulator (SERM) and may be considered as an alternative treatment option for the secondary prevention of osteoporotic fractures in post-menopausal women. *Most of our Ca is in our bone. Biphosphonate will bind to the surfaces of the bones and slow down the bone reabsorption action of the osteoclasts.

Question 64

T-score in normal, osteopenia and osteoporosis.

Answer 64

≥-1.0 = normal - 1.0 to -2.5 = osteopenia - 2.5 or lower = osteoporosis.

Question 65

28YO woman with palpitations and tremors of the hands. These started a month ago. She delivered her first child vaginally 3 months ago and is still breastfeeding. TSH 0.2 (0.5-5.7mU/L), free thyroxine (T4) 48 (9-18mmol/L), free triiodothyronine (T3) 15 (3.5-6.5mmol/L) and tests positive for thyroid peroxidase antibodies and she has a normal ESR. What is the most appropriate action?

Answer 65

Give propranolol. Classic example of postpartum thyroiditis in the hyperthyroid phase. 2 phases Hyperthyroid first 4 months Hypothyroidism 4 to 6 months later. It usually resolves spontaneously within a year from delivery. Tx is symptomatic. Levothyroxine if in hypothyroidism symptoms present.

Question 66

Shock (confusion, postural hypotension, tachycardia and oliguria) Abdominal pain (may be severe enough to mimic acute abdomen) Hypoglycemia Are signs and symptoms of...?

Answer 66

Addisonian crisis due to low cortisol levels. Tx IV fluids if shocked IV hidrocortisone 100mg followed by 8 hourly doses Calcium gluconate/chloride if hyperkalaemia Fluids and steroids resolve hyponatraemia Hypoglycemia treated with IV glucose infusion If it improves in 72 hours then switch to oral steroids. If adrenal pathology is identified then fludrocortisone may be indicated.

Question 67

Hashimoto's thyroiditis clinical features

Answer 67

Symptoms of hypothyroidism Tiredness Dry skin Cold intolerance AND The thyroid gland may be enlarged. Low T4 level and high TSH Associated with autoimmune conditions like Addison's, DM, and pernicious anaemia.

Question 68

A px with history of Addison's presents with suspected COVID-19, all vitals normal except 38.5C What should be done with his/her medications?

Answer 68

Double the dose of hydrocortisone. Not just in COVID-19, any infection. Pxs with Addison's are unable to produce sufficient endogenous steroids so hydrocortisone or prednisolone need to be doubled during these sick days. If she presented with signs of Addisonian crisis then call an ambulance and hydrocortisone IM.

Question 69

Nodule within thyroid gland or diffuse thyroid swelling Cervical lymphadenopathy or supraclavicular Unexplained hoarseness or voice change Enlarging painless thyroid mass over weeks. Usually with normal thyroid function test

Answer 69

Thyroid cancer!

Question 70

Thyroid adenoma

Answer 70

Benign tumour "Cold" (not producing thyroid hormones) Rarely "hot" (produces thyroid hormones = hyperthyroidism)

Question 71

Non toxic (simple) goitre vs. Toxic multinodular goitre

Answer 71

Non-toxic Non-functioning nodules TF test is normal Toxic Multinodular goitre Diffuse swelling of the thyroid gland Functioning nodules TSH low and T3, T4 high

Question 72

Hyperthyroidism Goitre Upper eyelid retraction, lid lag, exophthalmos TSH low T3 and T4 high Thyroid autoantibodies (anti-thyroid peroxidase, anti-thyroglobulin antibodies and TSH-receptor antibodies) may be seen Radioactive iodine uptake test is increased

Answer 72

Grave's disease!

Question 73

Hasimoto's vs De Quervain's thyroiditis

Answer 73

Hashimoto's Hypothyroidism Usually middle aged women Thyroid gland may enlarge rapidly (painless goitre) TSH high T3 and T4 low Thyroid autoantibodies (anti-thyroid peroxidase and anti-thyroglobulin antibodies) may be seen. ``` De Quervain's Neck pain Fever Lethargy soon after viral illness TSH low T3 and T4 high Radioactive iodine uptake test is decreased ```

Question 74

When to make a C-peptide test and why?

Answer 74

C-peptide is released at the same time as insulin, for every insulin molecule there is a molecule of C-peptide. If no insulin is produced then there won't be C-peptide. If C-peptide is detected (high levels) and the px has hyperglycemia then DM2 is more likely (as insulin is being produced but there is no response) Differentiates DM1 from DM2 ***Not accurate in LADA (Latent autoimmune diabetes of the adult, DM1 in <50 years)

Question 75

Difference between Osteoporosis, Paget's and Osteomalacia with serum calcium, phosphate and alkaline phosphate.

Answer 75

Osteoporosis ALL normal Paget's only alkaline phosphatase high. Calcium and phosphate normal Osteomalacia Low calcium and phosphate Alkaline phosphatase high.

Question 76

Grave's disease treatment for a woman that wants to become pregnant.

Answer 76

Propylthiouracil alone Even though carbamizole is better, only PTU is considered for pre conception women. Treatment can have a 12 to 18 month duration, remission is seen in 50% of cases. Carbimazole has been associated with aplasia cutis and omphalocele **New guidelines suggest PTU pre conception and during 1st trimester and at the beginning of the 2nd trimester change to carbimazole (reduces risk of hepatotoxicity with PTU) 98% cure rate is seen with surgery but medication may be attempted 1st**

Question 77

29YO male with a swollen, painful right wrist joints. He gives a hx of noticing change in shoe size, constipation, feeling cold and needing more warm clothes to keep him warm. His skin is found to be dry and his right wrist is erythematous and tender to touch. What is the single most likely diagnosis?

Answer 77

Pseudogout. Recognize hypothyroidism signs. The change in show size can be due to myxoedema. Pseudogout can be precipitated by hypothyroidism. Most affected joint = knee Other joints commonly affected> wrist, shoulder, and ankle. Positive birefringent crystals in synovial fluid elevation are pathognomonic of acute pseudogout.

Question 78

Acromegaly investigations

Answer 78

Initial test > insulin like growth factor (used as screening test and occasionally used to monitor disease) Most definitive test> Oral glucose tolerance (OGTT) with serial growth hormone measurements. In normal pxs, GH is usually suppressed with glucose. In acromegaly, there is no suppression of GH with glucose. GH levels are not recommended as they tend to vary during the day and are therefore unreliable.

Question 79

Summary of DM2 medications safety issues.

Answer 79

Remember With bad kidneys dont give MS (metformin and sulphonylureas) Heart has 4 chambers so dont use DPP4i (gliptins) Pie comes with the die (pioglitazone has risk of bladder Ca and HF) SPR cause weight gain (sulpho, pioglitazone and repaglinide) The rest causes weight loss except DPP4i (gliptins) which have no effect. SPR without the P have risk of hypoglycemia (Sulpho and repaglinide)