Cardiology/Misc Flashcards

Question

What is the "pill in the pocket" approach?

Answer 1

Paroxysmal AF is when the AF comes and goes in episodes, usually not lasting more than 48 hours. Patients should still be anti coagulated based on CHADSVASc score. They may be appropriate for a “pill in the pocket” approach. This is where they take a pill to terminate their atrial fibrillation only when they feel the symptoms of AF starting. To be appropriate for a pill in the pocket approach they need to have infrequent episodes without any underlying structural heart disease. They also need to be able to identify when they are in AF and understand when the treatment is appropriate. Flecanide is the usual treatment for a “pill in the pocket” approach.

Answer 2

Score: 0: no anticoagulation 1: consider anticoagulation >1: offer anticoagulation CHA2DS2-VASc Mnemonic C – Congestive heart failure H – Hypertension A2 – Age >75 (Scores 2) D – Diabetes S2 – Stroke or TIA previously (Scores 2) V – Vascular disease A – Age 65-74 S – Sex (female)

Answer 3

ORBIT score, used to be HAS-BLED. It is scored based on: Low haemoglobin or haematocrit Age (75 or above) Previous bleeding (gastrointestinal or intracranial) Renal function (GFR less than 60) Antiplatelet medications

Answer 4

Cor pulmonale is right sided heart failure caused by respiratory disease. The increased pressure and resistance in the pulmonary arteries (pulmonary hypertension) results in the right ventricle being unable to effectively pump blood out of the ventricle and into the pulmonary arteries. This leads to back pressure of blood in the right atrium, the vena cava and the systemic venous system.

Answer 5

COPD is the most common cause Pulmonary Embolism Interstitial Lung Disease Cystic Fibrosis Primary Pulmonary Hypertension

Answer 6

Adrenaline is produced by the “chromaffin cells” in the adrenal medulla of the adrenal glands. A phaeochromocytoma is a tumour of the chromaffin cells that secretes unregulated and excessive amounts of adrenaline. Adrenaline is a “catecholamine” hormone and neurotransmitter that stimulates the sympathetic nervous system and is responsible for the “fight or flight” response. In patients with a phaeochromocytoma the adrenaline tends to be secreted in bursts giving periods of worse symptoms followed by more settled periods.

Answer 7

24 hour urine catecholamines Plasma free metanephrines Measuring serum catecholamines is unreliable as this will naturally fluctuate and it will be difficult to interpret the result. Measuring 24 hour urine catecholamines gives an idea of how much adrenaline is being secreted by the tumour over the 24 hour period. Adrenaline has a short half life of only a few minutes in the blood, whereas metanephrines (a breakdown product of adrenaline) have a longer half life. This makes the level of metanephrines less prone to dramatic fluctuations and a more reliable diagnostic tool.

Answer 8

Alpha blockers (i.e. phenoxybenzamine) Beta blockers once established on alpha blockers Adrenalectomy to remove tumour is the definitive management Patients should have symptoms controlled medically prior to surgery to reduce the risk of the anaesthetic and surgery.

Answer 9

Aldosterone is a mineralocorticoid steroid hormone. It acts on the kidney to: Increase sodium reabsorption from the distal tubule Increase potassium secretion from the distal tubule Increase hydrogen secretion from the collecting ducts

Answer 10

Secondary hyperaldosteronism is where excessive renin stimulating the adrenal glands to produce more aldosterone. Serum renin will be high.

Answer 11

Renal artery stenosis Renal artery obstruction Heart failure

Answer 12

Aldosterone antagonists Eplerenone Spironolactone Treat the underlying cause Surgical removal of adenoma Percutaneous renal artery angioplasty via the femoral artery to treat in renal artery stenosis

Answer 13

Hyperaldosteronism is worth remembering as the most common cause of secondary hypertension. If you have a patient with a high blood pressure that is not responding to treatment consider screening for hyperaldosteronism with a renin:aldosterone ratio. One clue that could prompt you to test for hyperaldosteronism might be a low potassium however be aware that potassium levels may be normal.

Answer 14

Tumour producing PTH High PTH, hypercalcaemia

Answer 15

Low vitamin D or CKD High PTH, low/normal calcium

Answer 16

Hyperplasia High PTH, hypercalcaemia

Answer 17

Glycopyrronium bromide is used to treat excessive respiratory secretions and bowel colic in palliative care

Answer 18

Significant trauma (not “lifting something” or “bending to pick up something” etc) Age less than 20 or greater than 50 Past medical history of malignancy, ankylosing spondylitis or osteoporosis Chronic corticosteroid use (increased risk of fracture) An episode of back pain ongoing for 6 weeks or longer without improvement

Answer 19

Confusion Oculomotor disturbances (disturbances of eye movements) Ataxia

Answer 20

Synthetic ADH

Answer 21

A group of people is chosen who do not have the outcome of interest (for example, myocardial infarction). The investigator then measures a variety of variables that might be relevant to the development of the condition. Over a period of time the people in the sample are observed to see whether they develop the outcome of interest (that is, myocardial infarction)

Answer 22

In contrast with cohort and cross sectional studies, case control studies are usually retrospective. People with the outcome of interest are matched with a control group who do not. Retrospectively the researcher determines which individuals were exposed to the agent or treatment or the prevalence of a variable in each of the study groups. Where the outcome is rare, case-control studies may be the only feasible approach.

Answer 23

These are primarily used to determine prevalence. Prevalence equals the number of cases in a population at a given point in time. All the measurements on each person are made at one point in time. Prevalence is vitally important to the clinician because it influences considerably the likelihood of any particular diagnosis and the predictive value of any investigation.

Answer 24

ERCP - stents can be put in

Answer 25

Autoimmune hepatitis

Answer 26

IV sodium bicarbonate

Answer 27

Post-tonsillitis infection

Answer 28

Antipsychotic use, especially typical ones

Answer 29

Akathisia: Dystonia: Parkinsonism: Tardive dyskinesia:

Answer 30

Feeling restless like you can’t sit still. You may have the urge to tap your fingers, fidget, or jiggle your legs.

Answer 31

When your muscles contract involuntarily. It can be painful.

Answer 32

Symptoms are similar to Parkinson’s disease. You may have a tremor, difficulty finishing thoughts or speaking, and stiff facial muscles. ‌But while a loss of nerve cells causes Parkinson’s disease, the medication causes Parkinsonism.

Answer 33

Facial movements happen involuntarily. You may make a sucking or chewing motion with your mouth, stick out your tongue, or blink your eyes a lot.

Answer 34

Normal pressure hydrocephalus is a potentially reversible cause of dementia that can be seen in predominantly elderly patients.The classic triad of features is urinary incontinence, dementia and gait abnormality which develops over several months.

Answer 35

MRI Head can show evidence of enlarged ventricles The definitive investigation is a walking and cognitive assessment before and after large volume CSF removal. Patients that improve post CSF removal are considered to be candidates for surgery.

Answer 36

Treatment in patients fit for surgery is ventriculo-peritoneal shunting, otherwise they may be managed with conservative treatment and repeated CSF taps.

Answer 37

Haemochromatosis is an iron storage disorder that results in excessive total body iron and deposition of iron in tissues. The human haemochromatosis protein (HFE) gene is located on chromosome 6. The majority of cases of haemochromatosis relate to mutations in this gene, however there are other genes that can cause the condition. The haemochromatosis genetic mutation is autosomal recessive. This gene is important in regulating iron metabolism.

Answer 38

Chronic tiredness Joint pain Pigmentation (bronze / slate-grey discolouration) Hair loss Erectile dysfunction Amenorrhoea Cognitive symptoms (memory and mood disturbance)

Answer 39

The main diagnostic method is to perform a serum ferritin level. Ferritin is an acute phase reactant, meaning that it goes up with inflammatory conditions such as infection. Performing a transferrin saturation is helpful in distinguishing between a high ferritin caused by iron overload (in which case transferrin saturation is high) from a high ferritin due to other causes such as inflammation or non alcoholic fatty liver disease. If serum ferritin and transferrin saturation is high and there is no other reason then genetic testing can be performed to confirm haemochromatosis.

Answer 40

Liver biopsy with Perl’s stain can be used to establish the iron concentration in the parenchymal cells used to be the gold standard but has been surpassed by genetic testing.

Answer 41

Type 1 Diabetes (iron affects the functioning of the pancreas) Liver Cirrhosis Iron deposits in the pituitary and gonads lead to endocrine and sexual problems (hypogonadism, impotence, amenorrhea, infertility) Cardiomyopathy (iron deposits in the heart) Hepatocellular Carcinoma Hypothyroidism (iron deposits in the thyroid) Chrondocalcinosis / pseudogout (calcium deposits in joints) causing arthritis

Answer 42

Venesection (a weekly protocol of removing blood to decrease total iron) Monitoring serum ferritin Avoid alcohol Genetic counselling Monitoring and treatment of complications

Answer 43

Polyarteritis nodosa (PAN) is a medium vessel vasculitis. It is most associated with hepatitis B but can also occur without a clear cause or with hepatitis C and HIV.

Answer 44

It affects the medium sized vessels in locations such as the skin, gastrointestinal tract, kidneys and heart. This can cause renal impairment, strokes and myocardial infarction. The pulmonary vessels are not affected in PAN (Pulmonary vessels Are NOT affected).

Answer 45

It is associated with a rash called livedo reticularis. This is a mottled, purplish, lace like rash.

Answer 46

Takayasu’s arteritis is a form of large vessel vasculitis. It mainly affects the aorta and it’s branches. It also affect the pulmonary arteries. These large vessels and their branches can swell and form aneurysms or become narrowed and blocked. This leads to it’s other name of “pulseless disease”. It is diagnosed using CT or MRI angiography. Doppler ultrasound of the carotids can be useful in detecting carotid disease.

Answer 47

Eosinophilic granulomatosis with polyangiitis used to be called Churg-Strauss syndrome and is still often referred to by this name. It is a small and medium vessel vasculitis. It is most associated with lung and skin problems, but can affect other organs such as kidneys. It often presents with severe asthma in late teenage years or adulthood. A characteristic finding is elevated eosinophil levels on the full blood count.

Answer 48

Granulomatosis with polyangiitis is a small vessel vasculitis. It was previously known as Wegener’s granulomatosis. It affects the respiratory tract and kidneys. In the upper respiratory tract, it commonly affects the nose causing nose bleeds (epistaxis) and crusty nasal secretions, ears causing hearing loss and sinuses causing sinusitis. A classic sign in exams is the saddle-shaped nose due to a perforated nasal septum. This causes a dip halfway down the nose. In the lungs, it causes a cough, wheeze and haemoptysis. A chest x-ray may show consolidation, and it may be misdiagnosed as pneumonia. In the kidneys, it can cause rapidly progressing glomerulonephritis.

Answer 49

Microscopic polyangiitis and Churg-Strauss syndrome

Answer 50

Granulomatosis with polyangiitis

Answer 51

A rapidly progressive glomerulonephritis. Anti-Glomerular Basement Membrane antibody disease. Pulmonary haemorrhage with renal failure.

Answer 52

Microscopic polyangiitis is a small vessel vasculitis. The main feature of microscopic polyangiitis is renal failure. It can also affect the lungs causing shortness of breath and haemoptysis.

Answer 53

Suspected cases should be referred to a specialist, usually a rheumatologist, to guide diagnosis and management. Treatment usually involves a combination of steroids and immunosuppressants.

Answer 54

Cyclophosphamide Methotrexate Azathioprine Rituximab and other monoclonal antibodies

Answer 55

Sub-acute combined degeneration of the cord is a neurological complication of vitamin B12 deficiency caused by degeneration both the dorsal columns and corticospinal tracts (pain and temperature sensation are typically preserved).

Answer 56

Symmetrical distal sensory symptoms Usually beginning in the feet and spreading to the hands Varying degrees of ataxia Diminished vibration sense and proprioception in the legs Limb reflexes may be exaggerated or diminished or absent (can present with mixed Upper and Lower Motor Neuron signs) Autonomic bladder or bowel symptoms It may occur in the presence or absence of haematological manifestations.

Answer 57

B12, folate Raised homocysteine and a normal B12 may indicate a functional B12 deficiency (especially in patients who inhale nitrous oxide gas which inactivated B12) MRI Spine to rule out cervical myelopathy Nerve conduction studies will show predominantly axonal neuropathy B12 replacement Hydroxocobalamin 1 mg IM on alternate days until there is no further improvement then administer hydroxocobalamin 1 mg intramuscularly every 2 months (NICE Guidelines)

Answer 58

Charcot Marie Tooth disease, more usefully known as hereditary motor and sensory neuropathy (HMSN), is the most common group of genetic peripheral neuropathies

Answer 59

The disorder affects both the sensory and motor nerves of the peripheral nervous system, though motor problems are often more prominent clinically. The disease is length-dependent, meaning that patients present (usually in puberty) with symptoms affecting the feet, later progressing to involve the hands (usually as the knees become involved). As disease progresses (most commonly over decades) some key clinical features may be noted: Thickening and enlargement of the nerves themselves Symmetrical distal muscular atrophy (champagne bottle legs, and claw hand) Pes cavus (high-arched feet).

Answer 60

Diagnosis is made with a combination of nerve conduction studies and genetic testing. Patients with type 1 have reduced conduction velocity, whereas this is normal in type 2. While the disease may be incurable, most have a normal lifespan with expert supportive management. Majority require walking aids eventually, though requiring a wheelchair is uncommon.

Answer 61

It is most commonly caused by an autosomal dominant gene mutation (peripheral myelin protein 22).

Answer 62

Acquired hypothyroidism is where a child or adolescent develops an underactive thyroid gland when previously it was functioning normally. The most common cause of acquired hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis.

Answer 63

This causes autoimmune inflammation of the thyroid gland and subsequent under activity of the gland. It is associated with antithyroid peroxidase (anti-TPO) antibodies and antithyroglobulin antibodies. There is an association with other autoimmune conditions, particularly type 1 diabetes and coeliac disease.

Answer 64

This can lead to symptoms of: Fatigue and low energy Poor growth Weight gain Poor school performance Constipation Dry skin and hair loss

Answer 65

De Quervain’s Thyroiditis describes the presentation of a viral infection with fever, neck pain and tenderness, dysphagia and features of hyperthyroidism. There is a hyperthyroid phase followed by a hypothyroid phase as the TSH level falls due to negative feedback.

Answer 66

It is a self-limiting condition and supportive treatment with NSAIDs for pain and inflammation and beta-blockers for symptomatic relief of hyperthyroidism is usually all that is necessary.

Answer 67

Hyperthyroidism Diffuse goitre (without nodules) Graves eye disease Bilateral exophthalmos Pretibial myxoedema

Answer 68

Anxiety and irritability Sweating and heat intolerance Tachycardia Weight loss Fatigue Frequent loose stools Sexual dysfunction

Answer 69

Grave’s disease Toxic multinodular goitre Solitary toxic thyroid nodule Thyroiditis (e.g. De Quervain’s, Hashimoto’s, postpartum and drug-induced thyroiditis)

Answer 70

Hashimoto's and Graves

Answer 71

De Quervain's tenosynovitis is inflammation of the extensor pollicis longus and extensor pollicis brevis tendons at the base of the thumb.

Answer 72

Symptoms typically include pain at the base of the thumb, which is exacerbated by abduction of the thumb, gripping and ulnar movement of the wrist. It is associated with those carrying out repetitive thumb abduction such as office workers and musicians. There may be tenderness of the anatomical snuffbox and weakness of the hand.

Answer 73

Splinting and analgesia are the mainstay of treatment, with corticosteroid injections or surgery reserved for those in whom non-surgical treatment has failed.

Answer 74

Budd-Chiari syndrome is where a blood clot (thrombosis) develops in the hepatic vein, blocking the outflow of blood. It is associated with hyper-coagulable states. It causes acute hepatitis.

Answer 75

It presents with a classic triad of: Abdominal pain Hepatomegaly Ascites

Answer 76

Management involves anticoagulation (heparin or warfarin), investigating for the underlying cause of hyper-coagulation and treating hepatitis.

Answer 77

The severity of liver cirrhosis can be estimated by calculating the Child-Pugh score.

Answer 78

Caused by a mutation in the adenomatous polyposis coli (APC) gene and has an autosomal dominant inheritance pattern. Patients develop hundreds of adenomatous polyps in their teens and are virtually guaranteed to develop colorectal cancer by their 20s, unless they undergo prophylactic proctocolectomy.

Answer 79

Note that there is a high risk of developing duodenal cancer, so patients undergo regular endoscopic surveillance.

Answer 80

Hereditary Non-Polyposis Colorectal Cancer Is caused by a mutation in the mismatch repair genes MLH1/MSH2 and has an autosomal dominant inheritance pattern. Patients have an 80% risk of developing colorectal cancer by their 30s. There is an increased risk of additional cancers such as gastric, endometrial, breast, and prostate cancer. Patients are managed with regular endoscopic surveillance.

Answer 81

Is caused by a mutation in the STK11 gene and has an autosomal dominant inheritance pattern. Patients typically present in their teens with mucocutaneous pigmentaiton and hamartomatous polyps. Note that the risk of neoplastic transformation of hamartomatous polyps is low, but many polyps are present so patients are at increased risk of developing colorectal cancer. They are managed with regular endoscopic surveillance.

Answer 82

MSA is a Parkinson-plus syndrome, including the Parkinsonian triad of tremor, hypertonia, and bradykinesia, but does not include vertical gaze palsy. Characteristically, it involves severe early autonomic clinical features such as: postural hypotension (>20/10), incontinence, and impotence

Answer 83

Lambert-Eaton myasthenic syndrome has a similar set of features to myasthenia gravis. It causes progressive muscle weakness with increased use as a result of damage to the neuromuscular junction. The symptoms tend to be more insidious and less pronounced than in myasthenia gravis. Lambert-Eaton syndrome typically occurs in patients with small-cell lung cancer. It is a result of antibodies produced by the immune system against voltage-gated calcium channels in small cell lung cancer (SCLC) cells. These antibodies also target and damage voltage-gated calcium channels in the presynaptic terminals of the neuromuscular junction where motor nerves communicate with muscle cells.

Answer 84

Amifampridine allows more acetylcholine to be released in the neuromuscular junction synapses. It works by blocking voltage-gated potassium channels in the presynaptic cells, which in turn prolongs the depolarisation of the cell membrane and assists calcium channels in carrying out their action. This improves symptoms in Lambert-Eaton syndrome.

Answer 85

Ramsay-Hunt syndrome is caused by the varicella zoster virus (VZV). It presents as a unilateral lower motor neurone facial nerve palsy. Patients stereotypically have a painful and tender vesicular rash in the ear canal, pinna and around the ear on the affected side. This rash can extend to the anterior 2/3 of the tongue and hard palate. Treatment should ideally be initiated within 72 hours. Treatment is with: Prednisolone Aciclovir Patients also require lubricating eye drops.

Answer 86

Exopthalmos Signs include lid retraction, proptosis, lid lag and red, watery eyes.

Answer 87

Auto-antibodies target the extraocular muscles, causing swelling behind the eye which results in proptosis of the eyeballs.

Answer 88

This should raise suspicion of Wallenberg syndrome (also known as lateral medullary syndrome), usually from an infarction of the posterior inferior cerebellar artery (PICA).

Answer 89

This patient presents with a Horner's syndrome on examination as well as possible signs of vertigo, ataxia and dysphagia. This should raise suspicion of Wallenberg syndrome (also known as lateral medullary syndrome), usually from an infarction of the posterior inferior cerebellar artery (PICA). The presentation can be summarised by the mnemonic "DANVAH" - Dysphagia, ipsilateral Ataxia, ipsilateral Nystagmus, Vertigo, Anaesthesia (Ipsilateral facial numbness and contralateral pain loss on the body) and ipsilateral Horner's syndrome

Answer 90

TRH -- TSH -- T3 and T4

Answer 91

CRH - ACTH - cortisol

Answer 92

GHRH -- GH -- IGF-1 IGF-1 acts to stimulate muscle growth, increase bone density and strength, stimulate cell regeneration and reproduction and stimulates growth of internal organs

Answer 93

Increase intestinal and kidney reabsorption of Ca2+ Increase osteoclast activity and therefore calcium absorption from bone

Answer 94

Increase sodium reabsorption from the distal tubule (hence increase in BP) Increase potassium secretion from the distal tubule Increase hydrogen secretion from the collecting ducts

Answer 95

Addison’s Disease refers to the specific condition where the adrenal glands have been damaged, resulting in a reduction in the secretion of cortisol and aldosterone. This is also called Primary Adrenal Insufficiency. The most common cause is autoimmune.

Answer 96

Secondary Adrenal Insufficiency is a result of inadequate ACTH stimulating the adrenal glands, resulting in low cortisol release. This is the result of loss or damage to the pituitary gland. This can be due to surgery to remove a pituitary tumour, infection, loss of blood flow or radiotherapy. There is also a condition called Sheehan’s syndrome where massive blood loss during childbirth leads to pituitary gland necrosis.

Answer 97

Tertiary Adrenal Insufficiency is the result of inadequate CRH release by the hypothalamus. This is usually the result of patients being on long term oral steroids (for more than 3 weeks) causing suppression of the hypothalamus. When the exogenous steroids are suddenly withdrawn the hypothalamus does not “wake up” fast enough and endogenous steroids are not adequately produced. Therefore long term steroids should be tapered slowly to allow time for the adrenal axis to regain normal function.

Answer 98

Fatigue Nausea Cramps Abdominal pain Reduced libido Bronze hyperpigmentation to skin (ACTH stimulates melanocytes to produce melanin) Hypotension (particularly postural hypotension)

Answer 99

A short synacthen test, or ACTH stimulation test, is the test of choice to diagnose adrenal insufficiency. In primary adrenal failure the ACTH level is high as the pituitary is trying very hard to stimulate the adrenal glands without any negative feedback in the absence of cortisol. In secondary adrenal failure the ACTH level is low as the reason the adrenal glands are not producing cortisol is that they are not being stimulated by ACTH.

Answer 100

Addisonian crisis is the term used to describe an acute presentation of severe Addisons, where the absence of steroid hormones leads to a life threatening presentation. They present with: Reduced consciousness Hypotension Hypoglycaemia, hyponatraemia, hyperkaemia Patients can be very unwell It can be the first presentation of Addisons Disease or triggered by infection, trauma or other acute illness in someone with established Addisons. It can present in someone on long term steroids suddenly withdrawing those steroids. Do not wait to perform investigations and establish a definitive diagnosis before treating someone with suspected Addisonian Crisis as this is life threatening and they need immediate treatment.

Answer 101

Intensive monitoring if unwell Parenteral steroids (i.e. IV hydrocortisone 100mg stat then 100mg every 6 hours) IV fluid resuscitation Correct hypoglycaemia Careful monitoring of electrolytes and fluid balance

Answer 102

Insulin-like Growth Factor 1 (IGF-1) is the initial screening test (raised) Oral glucose tolerance test whilst measuring growth hormone (high glucose normally suppresses growth hormone) MRI brain for the pituitary tumour

Answer 103

There are medication that can be used to block growth hormone Pegvisomant (GH antagonist given subcutaneously and daily) Somatostatin analogues to block GH release (e.g. ocreotide) Dopamine agonists to block GH release (e.g. bromocriptine)

Answer 104

Bilateral adrenal hyperplasia (most common) An adrenal adenoma secreting aldosterone (known as Conn’s Syndrome) Familial hyperaldosteronism type 1 and type 2 (rare) Adrenal carcinoma (rare)

Answer 105

Secondary hyperaldosteronism is where excessive renin stimulating the adrenal glands to produce more aldosterone. Serum renin will be high.

Answer 106

There are several causes of high renin levels and they occur when the blood pressure in the kidneys is disproportionately lower than the blood pressure in the rest of the body: Renal artery stenosis Renal artery obstruction Heart failure

Answer 107

Renal artery stenosis is a narrowing of the artery supplying the kidney. This is usually found in patients with atherosclerosis, as an atherosclerotic plaque causes narrowing of this vessel similar to the narrowing of the coronary arteries found in angina. This can be confirmed with a doppler ultrasound, CT angiogram or magnetic resonance angiography (MRA).

Answer 108

Eplerenone Spironolactone

Answer 109

Treatment resistant HTN

Answer 110

Central pontine myelinolysis (CPM) is also (and more accurately) known as “osmotic demyelination syndrome”. It is usually a complication of long term severe hyponatraemia (< 120 mmols/l) being treated too quickly (> 10 mmol/l increase over 24 hours). As blood sodium level falls water will move by osmosis across the blood-brain barrier into the cells of the brain from the area of low concentration of solutes (the blood) to the area of high concentration of solutes (the brain). This causes the brain to swell. The brain adapts to this by reducing the solutes in the brain cells so that water is balanced across the blood-brain barrier and the brain does not become oedematous. This adaptation takes a few days. Therefore, if the hyponatraemia has been present and severe for a long time the brain cells will also have a low osmolality. This is not a problem until the blood sodium levels rapidly rise. When this happens water will rapidly shift out of the brain cells and into the blood. This causes two phases of symptoms: First phase: this is due to the electrolyte imbalance and the patient presents as encephalopathic and confused. They may have a headache or nausea and vomiting. These symptoms often resolve prior to the onset of the second phase. Second phase: this is due to the demyelination of the neurones, particularly in the pons. This occurs a few days after the rapid correction of sodium. This may present as spastic quadriparesis, pseudobulbar palsy and cognitive and behavioural changes. There is a significant risk of death. Prevention is essential as treatment is only supportive once CPM occurs. A proportion of patients make a clinical improvement but most are left with some neurological deficit.

Answer 111

Anti-diuretic hormone (ADH) is produced in the hypothalamus and secreted by the posterior pituitary gland. It is also known as “vasopressin”. ADH stimulates water reabsorption from the collecting ducts in the kidneys. SIADH is a condition where there is inappropriately large amounts of ADH. This may be the result of the posterior pituitary secreting too much ADH or the ADH may be coming from somewhere else, for example a small cell lung cancer. The excessive ADH results in excessive water reabsorption in the collecting ducts. This water dilutes the sodium in the blood so you end up with a low sodium concentration (hyponatraemia). The excessive water reabsorption is not usually significant enough to cause a fluid overload, therefore you end up with a “euvolaemic hyponatraemia”. The urine becomes more concentrated as less water is excreted by the kidneys therefore patients with SIADH have a “high urine osmolality” and “high urine sodium”.

Answer 112

Adrenaline is produced by the “chromaffin cells” in the adrenal medulla of the adrenal glands. A phaeochromocytoma is a tumour of the chromaffin cells that secretes unregulated and excessive amounts of adrenaline. Adrenaline is a “catecholamine” hormone and neurotransmitter that stimulates the sympathetic nervous system and is responsible for the “fight or flight” response. In patients with a phaeochromocytoma the adrenaline tends to be secreted in bursts giving periods of worse symptoms followed by more settled periods.

Answer 113

25% are familial and associated with multiple endocrine neoplasia type 2 (MEN 2).

Answer 114

24 hour urine catecholamines Plasma free metanephrines Measuring serum catecholamines is unreliable as this will naturally fluctuate and it will be difficult to interpret the result. Measuring 24 hour urine catecholamines gives an idea of how much adrenaline is being secreted by the tumour over the 24 hour period. Adrenaline has a short half life of only a few minutes in the blood, whereas metanephrines (a breakdown product of adrenaline) have a longer half life. This makes the level of metanephrines less prone to dramatic fluctuations and a more reliable diagnostic tool.

Answer 115

Alpha blockers (i.e. phenoxybenzamine) Beta blockers once established on alpha blockers Adrenalectomy to remove tumour is the definitive management Patients should have symptoms controlled medically prior to surgery to reduce the risk of the anaesthetic and surgery.

Answer 116

Headache, tachycardia and htn

Answer 117

Serum LH and FSH on day 2 to 5 of the cycle Serum progesterone on day 21 of the cycle (or 7 days before the end of the cycle if not a 28-day cycle). Anti-Mullerian hormone Thyroid function tests when symptoms are suggestive Prolactin (hyperprolactinaemia is a cause of anovulation) when symptoms of galactorrhea or amenorrhoea

Answer 118

A rise in progesterone on day 21 indicates that ovulation has occurred, and the corpus luteum has formed and started secreting progesterone.

Answer 119

Ovarian reserve It is released by the granulosa cells in the follicles and falls as the eggs are depleted.

Answer 120

Pre-eclampsia features a triad of: Hypertension Proteinuria Oedema

Answer 121

Headache Visual disturbance or blurriness Nausea and vomiting Upper abdominal or epigastric pain (this is due to liver swelling) Oedema Reduced urine output Brisk reflexes

Answer 122

Urine protein:creatinine ratio (above 30mg/mmol is significant) Urine albumin:creatinine ratio (above 8mg/mmol is significant)

Answer 123

Labetolol is first-line as an antihypertensive Nifedipine (modified-release) is commonly used second-line Methyldopa is used third-line (needs to be stopped within two days of birth) Intravenous hydralazine may be used as an antihypertensive in critical care in severe pre-eclampsia or eclampsia IV magnesium sulphate is given during labour and in the 24 hours afterwards to prevent seizures Fluid restriction is used during labour in severe pre-eclampsia or eclampsia, to avoid fluid overload

Answer 124

HELLP syndrome is a combination of features that occurs as a complication of pre-eclampsia and eclampsia. It is an acronym for the key characteristics: Haemolysis Elevated Liver enzymes Low Platelets