OSCE Clinical Conditions

Question 1

AKI Pathophysiology

Answer 1

It is an abrupt loss of kidney function, that develops within 7 days.

Pre renal – due to decreased renal perfusion. This could be due to decreased ECF volume, so hypovolaemia (blood loss or fluid loss), systemic vasodilation (sepsis, cirrhosis or anaphylaxis) or cardiac failure. It may be due to impaired renal autoregulation, which usually maintains normal perfusion. Pre glomerular vasoconstriction can be due to: sepsis, hypercalcaemia, hepatorenal syndrome or drugs (eg NSAIDs).

Post glomerular vasodilation can be due to: ACE inhibitors or angiotensin II antagonists. Post renal – due to obstruction of urine flow once it has left the tubules, so may be in ureters, bladder or urethra. This obstruction can be caused by: calculi (kidney stones), blood clot, papillary necrosis or a tumour. There may be pressure from the outside causing obstruction – prostatic hypertrophy, malignancy, aortic aneurysm, diverticulitis or accidental ligation of the ureter in surgery.

Intrinsic – this is direct injury to the kidney. Acute tubular necrosis can occur if pre renal AKI is not treated quickly – it will cause severe acute ischaemia. In toxic acute tubular necrosis, the damage is caused by nephrotoxins. They damage the epithelial cells which line the tubules, causing cell death and shedding into the lumen. Nephrotoxins can be endogenous (myoglobin, urate and bilirubin) or exogenous (drugs – gentamicin, ACE inhibitors, NSAIDs and angiotensin receptor blockers). Acute glomerulonephritis occurs due to immune disease attacking the kidney. This may be primary (only affecting the kidney) or secondary (kidneys involved as part of something affecting the whole body). Acute tubulo-interstitial nephritis is inflammation of the kidney interstitium. This can be caused by infection (acute pyelonephritis – ascending UTI) or nephrotoxins.

Question 2

AKI Symptoms and signs

Answer 2

The clinical picture is usually due to the underlying cause.

Disturbances in kidney function can lead to electrolyte imbalances which can cause a variety of symptoms: fatigue, loss of appetite, headache, nausea and vomiting.

Increase in potassium levels in the blood can lead to abnormal heart rhythms.

Kidneys may be unable to produces sufficient amounts of urine, leading to oliguria or anuria. If the AKI is caused by inflammation there may be flank pain

Question 3

AKI Investigations and outcomes​

Answer 3

Serum biochemistry – increased urea and creatinine in all forms of AKI

Urine dipstick – blood and protein present on glomerulonephritis

Urine microscopy - hyaline cast if pre renal cause, muddy brown cast in ATN, red blood cell cast in glomerulonephritis

Soluble immunological tests – circulating antibodies present if immune disorder

Imaging – ultrasound to check renal size and presence of obstruction

Biopsy – this is carried out if pre renal and post renal are ruled out, and a diagnosis of ATN cannot be confidently made

Question 4

AKI Progression​

Answer 4

If the cause of pre renal AKI is not recognised and treated quickly, this can develop to ischaemic acute tubular necrosis (ATN).

Reduced kidney function means electrolyte imbalances could occur, leading to dangerous complications – hyperkalaemia and metabolic acidosis.

The risk of developing chronic kidney failure is increased.

Question 5

AKI Treatment​

Answer 5

The treatment of AKI depends on its cause.

Pre renal – volume correction. If it caused by hypovolaemia, there will be fluid replacement and if it caused by heart failure (fluid overload) a diuretic will be used (furesomide).

Post renal – urological intervention to re establish urine flow

Intrinsic – maintaining good kidney perfusion and avoiding nephrotoxins (come of nephrotoxic drugs), supportive treatment Some patients may require dialysis if kidney function deteriorates further.

Question 6

Alcoholic liver disease Pathophysiology​

Answer 6

The first stage of alcoholic liver disease is fatty liver or steatosis. This is due to the metabolism of alcohol, which produces NADH from NAD+. Increased NADH means that there is an increase in fatty acid synthesis, and decreased NAD+ means there is less oxidation of fatty acids. The increased fatty acids are converted to triacylglycerides, which accumulate in the liver, resulting in a fatty liver.

The next stage of alcoholic liver disease is alcoholic hepatitis, which is inflammation of the hepatocytes. At these two stages, alcoholic liver disease is reversible.

The third stage is cirrhosis. There is necrosis of liver cells, followed by regeneration in nodules surrounded by bands of fibrosis (collagen). There is reduction in liver function at this stage. There is increased resistance to blood flow, which causes portal hypertension.

Question 7

Alcoholic liver disease Symptoms and signs

Answer 7

Symptoms are not usually seen until the liver becomes badly damaged. Early symptoms are generally vague: abdominal pain, loss of appetite and fatigue.

As the liver becomes more damaged, more obvious symptoms and signs are present. Jaundice is present (mixed unconjugated and conjugated hyperbilirubinaemia). Easy bruising and bleeding due to reduced clotting factors. Oedema and ascites due to reduced oncotic pressure (the liver makes proteins). Palmar erythema (red blotchy palms), clubbing of the nails and Dupuytren’s contracture are all seen in the hands. Hepatosplenomegaly (enlarged liver and spleen) may also be present.

If there is portal hypertension, there may be oesophageal varices, rectal varices (haemorrhoids) and caput medusae. If there are varices present, there will be signs and symptoms of anaemia due to blood loss.

Question 8

Alcoholic liver disease Investigations

Answer 8

Early alcoholic liver disease is usually discovered by a liver function test in a routine health check, and there will be raised liver enzymes – ALT and AST.

A blood test will pick up low levels of serum albumin, high levels of bilirubin and deranged clotting.

Imaging and a biopsy may be done if the blood tests suggest more advanced alcoholic liver disease (hepatitis and cirrhosis).

Question 9

Alcoholic liver disease Progression

Answer 9

There are the three stages of alcoholic liver disease fatty liver disease, alcoholic hepatitis and cirrhosis.

If the patient does not stop drinking alcohol at the early stages, they’re more likely to progress to the next. However, not all alcoholics develop cirrhosis. Fatty liver disease and alcoholic hepatitis are both reversible, but cirrhosis is not. However, if the patient stops drinking alcohol at this stage their liver function can be maintained and prevented from getting worse and developing further complications.

The complications of alcoholic liver disease are complete liver failure, hepatocellular carcinoma, Wernicke-Korsakoff syndrome (thiamine deficiency), encephalopathy (due to increased toxins), dementia and epilepsy. There are also the complications due to portal hypertension

Question 10

Alcoholic liver disease treatment

Answer 10

The most important advice to give the patient is abstinence from alcohol.

If they have been diagnosed at the fatty liver stage, then they can begin drinking alcohol again after a few weeks (if they stick to the NHS guidelines). However, with alcoholic hepatitis and cirrhosis lifelong abstinence is advised.

If the patient is dependent on alcohol, then they may experience withdrawal symptoms, so they may need to gradually reduce alcohol intake. They may need to be inpatients in rehabilitation clinics, depending on level of dependence. It is important to advice the patient of any help in the community that may be available to them, like support groups or online forums. There are medications that help prevent relapse – like disulfarim.

Malnutrition is also common in people who have alcoholic liver disease, so they may need dietary advice.

Liver damage may mean it is unable to store glycogen, which mean there may need to be changes to the diet.

Corticosteroids can be given for alcoholic hepatitis, and liver transplant may be considered if liver failure occurs once the patient has stopped drinking alcohol.

Question 11

Anaemia Pathophysiology

Answer 11

Anaemia is reduced haemoglobin concentration in the blood. This can be due to a variety of reasons:

Problems making haemoglobin – gene mutations (thalassaemias and sickle cell disease), lack of iron (blood loss, dietary, chronic disease) and deficiency in building blocks for DNA synthesis (vitamin D or folate/B12 – diet, pernicious anaemia), problems with red cell membrane (hereditary spherocytosis and elliptocytosis), There may be reduced production of red cells due to bone marrow failure – but this would also reduced white cell and platelet count.

May be due to destruction of red cells, which can be immune (transfusion, haemolytic disease of the newborn, autoimmune) or mechanical (heart valves, MAHA).problems with red cell metabolism – G6PD deficiency and Pyruvate kinase deficiency and increased red cell removal – enlarged spleen.

Kidney failure can also cause anaemia because they will be unable to produce erythropoietin to stimulate erythropoiesis.

Less haemoglobin means that our bodies are unable to carry as much oxygen. The body’s physiological response to this is increase cardiac output, increased heart rate, increased 2-3 BPG and increased erythropoietin in the kidneys.

Question 12

Anaemia Symptoms and signs

Answer 12

Symptoms – dyspnoea, weakness, lethargy (TATT), palpitations and headaches

Signs – Pallor (check conjunctiva and palmar creases), tachycardia, koilonychia (iron deficiency), glossitis and angular stomatitis (iron deficiency), jaundice (haemolytic

Question 13

Anaemia investigations and outcomes

Answer 13

Haemoglobin conc - <13.5g/dl adult men <11.5g/dl adult women

Reticulocyte count – reticulocytosis (making new red blood cells) should be increased due to low haemoglobin, if it is not increased this suggest that red blood cells are not being produced appropriately

Mean cell volume – microcytic/macrocytic/normocytic

Mean cell haemoglobin – hypochronic/hyperchronic/normochronic

Ferritin levels – only useful if LOW (confirms iron deficiency), because it is an acute phase protein so can be normal/raised for many reasons

Serum iron – low in iron deficiency

Folate levels – low in folate deficiency

Serum vitamin B12 – low in B12 deficiency

Direct Coombes Test – positive if autoimmune Bone marrow exa

Question 14

Anaemia Progression

Answer 14

The progression and complication depend on the underlying cause of the anaemia.

However, all types of anaemia have increased risk of tachycardia and heart failure as the heart increases its workload to try to get enough oxygen around the body.

Question 15

Anaemia treatment

Answer 15

Treatment of anaemia depends on the type and underlying cause.

For example, patients with anaemia caused by deficiencies may be given dietary advice so they will no longer have these deficiencies. They may also be given supplements (iron tablets).

If the anaemia is caused by a GI bleed, the cause of the GI bleed must be established and this will be treated.

For example, if NSAIDs are causing the bleed, the patient will be taken off NSAIDs and put on an alternative medication.

If the anaemia is being caused by blood loss due to menorrhagia the patient may be put on the COCP to try and stop the periods being so heavy.

In an emergency, patients with anameia may be given a blood transfusion (does not happen commonly).

Question 16

Asthma Pathophysiology​

Answer 16

Asthma is a chronic disorder characterised by airway wall inflammation and remodelling. There is the early and late phase responses.

The early phase response is the initial response to an allergen, due to its interaction with mast cell fixed IgE. This causes release of histamine and other spasmogens, causing immediate bronchospasm.

The late phase response causes: epithelial damage, thickening of the basement membrane and mucus production due to leucocytes. Remodelling of the airways is due to loss of cilia, hyperplasia of smooth muscle and collagen deposition in the basement membrane.

Asthma is a reversible airflow obstruction. Triggers cause the airway smooth muscle to contract, narrowing airway radius, increasing resistance and therefore reducing airflow.

Question 17

Asthma Symptoms and signs

Answer 17

Symptoms – dry cough – worse at night (lack of sleep), exercise induced (less participation in activities), wheeze – polyphonic, high pitched, expiratory, breathlessness, chest tightness and variable airflow obstruction

Signs – hyperexpansion of the chest (barrel chest), hyper resonant on percussion and a polyphonic wheeze on expiration It is associated with other conditions like eczema and hay fever.

Question 18

Asthma Investigations and outcomes

Answer 18

Spirometry – low PEFR, low FEV1/FVC ratio, >12% increase in FEV1 after salbutamol (reversible airflow obstruction)

Allergy testing – testing for triggers of asthma (dogs/cats)

Chest xray – this is done to exclude any other conditions

The diagnosis of asthma is a clinical one, there is no definition of symptoms or findings on investigation.

Question 19

Asthma Progression​

Answer 19

If asthma is left untreated, the chronic inflammation can lead to irreversible obstruction due to airway remodelling. Patients asthma will become more severe if they are not complying with their treatment.

Severe, acute episodes of asthma require hospitalisation and can be life threatening. Severe acute asthma is defined as any one of: unable to complete sentences, pulse >110 bpm, respiration rate > 25 per minute or peak expiratory flow 33-50% of predicted. This becomes life threatening if there are any of the following features: PEF <33%, PaO2 < 8kPa, PaCO2 > 4.5kPa, silent chest, feeble respiratory effort, hypotension, bradycardia, arrhythmia, exhaustion, confusion or coma.

Question 20

Asthma Treatment​

Answer 20

The first step in management of asthma is patient education, so they know how to recognise their symptoms, use their medication appropriately and use services available.

In terms of primary prevention, the patient is advised to stop smoking, get fresh air, reduce exposure to triggers and lose weight.

In terms of pharmacological management there are five steps. The first step is an inhaled short acting B2 agonist (eg salbutamol). The next step is the addition of a regular preventative therapy – a corticosteroid (eg beclametasone). The third step is the addition of a long acting B2 agonist (eg salmeterol). Step 4 is the addition of a trial therapy, such as: muscarinic antagonist (eg ipatropium bromide), leukotriene receptor antagonist (eg montelukast) or a methylxanthine (eg theophylline). The final step is frequent use of oral steroids (eg prednisolone). If the patient’s asthma is under control, there will be a stepwise reduction of treatment.

Question 21

Atrial fibrillation Pathophysiology​

Answer 21

This is the most common arrhythmia. The normal, regular impulses from the SAN are overwhelmed by disorganised electrical impulses. This causes irregular conduction of ventricular impulses.

Atrial fibrillation can be caused by hypertension, heart valve disease, thyrotoxicosis and excess alcohol consumption. However, in many patients no underlying cause can be found.

Question 22

Atrial fibrillation Investigations and outcomes

Answer 22

Irregular pulse on examination

ECG – there will be no visible P waves and an irregularly irregular QRS comple

Question 23

Atrial fibrillation Progression​

Answer 23

Having atrial fibrillation increases the risk of stroke. Lack of organised contraction can lead to stagnant blood, therefore increasing the risk of thrombus formation. The thrombus can be carried in the blood stream – becoming an embolus. It can reach the cerebral vessels, causing an ischaemic stroke or a TIA.

The risk of a patient with atrial fibrillation having a stroke depends on other risk factors, such as hypertension, diabetes and a history of blood clots.

In extreme cases of atrial fibrillation, heart failure can occur as the heart is unable to pump blood around the body.

Question 24

Atrial fibrillation Treatment​:

Answer 24

If there is an underlying cause (such as hyperthyroidism) then the underlying cause is treated.

Anti coagulation is given to reduce the risk of stroke – warfarin is often used.

Rate control is considered first, usually with a beta blocker or a calcium channel blocker (verapamil). If rate control is not sufficient, then drugs are given for rhythm control (amiodarone or a beta blocker).

Question 25

Atrial fibrillation Symptoms and signs:

Answer 25

Symptoms – palpitations, tiredness, breathlessness, dizziness and feeling faint Signs – irregular pulse Many patients will not have any symptoms.

Question 26

Cerebrovascular disease Pathophysiology​

Answer 26

This includes any vascular disease of the cerebral circulation: TIA, stroke and vascular dementia. Ischaemic strokes (cerebral infarct) are caused by a blockage of a blood vessel of the brain by either a thrombus or an embolism (cardiac embolism due to atrial fibrillation), which causes part of the brain to have insufficient blood supply. These account for 85% of strokes. Heamorrhagic strokes (intracerebral haemorrhage) are caused by rupture of cerebral blood vessels and are caused by: hypertension, aneurysm, anticoagulation, thrombocytopenia, thrombolysis, drugs (cocaine/ amphetamines) and tumours. These account for 15% of strokes. TIA is a transient ischaemic attack. It is a sudden onset, focal disturbance of brain function. To be defined as a TIA rather than a stroke, it will completely resolve within 24 hours. Vascular dementia is generalised intellectual loss seen due to multiple infarcts. Mood changes are prominent in this type of dementia.

Question 27

Cerebrovascular disease Symptoms and signs:

Answer 27

The presentation of a patient who has had a stroke depends on the location of the cerebrovascular accident. Frontal lobe symptoms – motor, speech output, incontinence, personality changes Parietal lobe symptoms – sensory, inferior homonymous quadrantanopia Temporal lobe symptoms – taste and smell, hearing and balance, speech input, memory, superior homonymous quadrantanopia Occipital lobe symptoms – homonymous hemianopia There is a sudden onset of symptoms. If it is a haemorrhagic stroke the patient may also have had a headache

Question 28

Cerebrovascular disease Investigations and outcomes

Answer 28

Check blood glucose as a differential is hypoglycaemia ECG – check if the patient has atrial fibrillation Brain imaging – CT scan will immediately show if haemorrhage, MRI will show infarct

Question 29

Cerebrovascular disease Progression

Answer 29

Once a patient has had a TIA they are at a much higher risk of having a stroke in the future. The injury to the brain following a stroke can lead to widespread and long lasting problems. Patients will recover from their stroke at different rates. They will go through stroke rehabilitation to help them with their specific needs. They may need help relearning how to carry out day to day tasks. Having a stroke has psychological and physical effects – some patients may become reliant on carers following their stroke. In terms of vascular dementia, as there is currently no cure and no way to reverse the damage the condition gets worse over time. Some of the more advanced symptoms are: hallucinations, incontinence, personality changes and difficulty walking

Question 30

Cerebrovascular disease Treatment​:

Answer 30

The treatment depends on the type of stroke. If it has been confirmed that it is an ischaemic stroke then thrombolysis is used to break down the clot (alteplase). This is most effective if it is used as soon as possible after the stroke has occurred. Ischaemic stroke is also an indication for fibrinolytic drugs (streptokinase/recombinant tPAs). Patients are also likely to be given an anti platelet (aspirin) and an anti coagulant (warfarin/heparin). They may be given drugs to lower their risk factors for further ischaemic strokes – anti hypertensives and statins. For a haemorrhagic stroke, anti hypertensives are often given to reduce the blood pressure of the patient. If they were previously on any anti coagulants they will be given therapy to reverse the effects – vitamin K in the case of warfarin and protamine sulphate in the case of heparin. After a TIA, although the the symptoms will have completely disappeared, the patient will be counselled on lifestyle changes to reduced their risk of stroke in the future (diet, exercise, smoking and alcohol). They may also be given medication to reduce their risk factors, like anti platelets, anti coagulants and anti hypertensives. In terms of vascular dementia there is no cure, and the treatment is mainly treating the underlying conditions, so making lifestyle changes and taking the medications mentioned above.

Question 31

COPD Pathophysiology​

Answer 31

COPD is a chronic, slowly progressive disorder characterised by airflow obstruction which does not change markedly over several months. It is caused by an abnormal inflammatory response of the lung to noxious stimuli like cigarette smoke or pollution. Another, much less common cause of COPD is alpha 1 anti trypsin deficiency, which causes emphysema as well as liver damage. Chronic bronchitis and emphysema are two forms of COPD. It is a type of type 2 respiratory failure, with increased respiratory rate, increased CO2 and decreased O2.

Question 32

COPD Symptoms and signs

Answer 32

Symptoms – productive cough (white/clear sputum), wheeze, breathlessness, many years of a smokers cough Signs – quiet wheezes, accessory muscles of respiration used, pursed lip breathing, hyperventilation in prolonged expiration and hyperinflation of the lungs (barrel chest)

Question 33

COPD Investigations and outcomes

Answer 33

Chest X-ray – excludes other conditions MRC dyspnoea scale (history) Spirometry – low PEFR, low FEV1/FVC ratio CT (high resolution) – can detect emphysema ABG – high CO2, low O2

Question 34

COPD Progression​:

Answer 34

MRC dyspnoea scale – this has 5 stages. Stage 1 is not being troubled by breathlessness unless doing strenuous exercise. Stage 2 is short of breath when hurrying or going up hill. Stage 3 is walking slower than others when on flat ground and having to stop for breath when walking at own pace. Stage 4 is stopping for breath after about 100m or walking for a few minutes on the flat. Stage 5 is being too breathless to leave the house and becoming breathless when getting dressed or undressed. Acute exacerbations occur, usually due to infection. They are a sudden worsening of symptoms – increased shortness of breath, increased coughing, more sputum production and a change of sputum colour to green or yellow.

Question 35

COPD Treatment​:

Answer 35

The most important part of management of COPD is counselling the patient to stop smoking. Even in advanced disease, stopping smoking can slow the progression. Drug therapy is used in long term management and short term management of acute exacerbation. Inhaled bronchodilators (beta 2 agonists) and corticosteroids are used. Antibiotics are given as soon as sputum turns yellow, to shorten the length of the exacerbation. Oxygen therapy is used to increase oxygen saturation – it is a treatment for hypoxia not breathlessness. It is important to realise that giving high flow oxygen to COPD patients can lead to respiratory depression as it removes their respiratory drive. Pulmonary rehabilitation is a training programme which will improve exercise capacity. Lung volume reduction surgery is sometimes carried out, in which the damaged parts of the lung are taken out, leaving the relatively well functioning parts of the lung to expand and work more efficiently. This improves the quality of life for some COPD patients. It is also important to treat any comorbidities.

Question 36

Diabetes Pathophysiology

Answer 36

There are two types of diabetes. Type 1 diabetes – this is due to the autoimmune destruction of the beta cells of the islets of Langerhans in the pancreas. This means they are unable to produce insulin. Insufficient insulin means that glucose cannot be taken into the cells and used for energy, leading to hyperglycaemia. Type 2 diabetes – this is due to insulin resistance, and slow progressive loss of beta cells. This resistance to insulin means that cells are unable to take up circulating glucose, leading to hyperglycaemia.

Question 37

Diabetes Symptoms and signs

Answer 37

The classic picture of type 1 diabetes is a young person with a history of a recent viral infection who is feeling very tired. They appear with a classic triad of symptoms: polyuria – the kidney cannot re absorb all of the extra glucose, so it remains in the tubule, osmotically pulling water into the tubule too and excreted as large amounts of urine, polydipsia – thirst due to excessive water loss, and weight loss as protein and fat are metabolised due to the absence of glucose. Patients with unmanaged type 1 diabetes may present with ketoacidosis – hyperventilation, nausea, vomiting, dehydration and abdominal pain. Patients will type 2 diabetes may present with the classics triad of symptoms (polyuria, polydipsia and weight loss). However, they are more likely to present with a variety of symptoms: lack of energy, persistent infections (thrush or feet infections), slow healing or visual problems.

Question 38

Diabetes Investigations and outcomes

Answer 38

Random venous plasma glucose >11.1 mmol/l Fasting plasma glucose >7 mmol/l Plasma glucose >11.1 mmol/l 2 hours after 75g anhydrous glucose in an oral glucose tolerance test HbA1c > 6%

Question 39

Diabetes Progression​

Answer 39

Long term diabetics have a number of micro vascular and macro vascular complications, particularly if their blood glucose is not well controlled. Macro vascular complications are: increased risk of stroke, increased risk of myocardial infarction and poor circulation to the peripheries (particularly the feet). Micro vascular complications are: diabetic eye disease, diabetic kidney disease, diabetic neuropathy and diabetic feet. Visual problems can arise due to changes in the lens from osmotic effects – glaucoma, but the more important problem is diabetic retinopathy. This is damage to the blood vessels in the retina that can lead to blindness. Nephropathy is due to damage to the glomeruli, poor blood supply (damage to blood vessels) or damage due to infections of the urinary tract which are more common in diabetics. An early sign of nephropathy is the presence of increased protein in the urine. Neuropathy is due to damage to the peripheral nerves, causing changes or loss in sensation and changes in the function of the autonomic nervous system. Poor blood supply, damage to nerves and increased risk of infection means that the feet of patients with diabetes are particularly vulnerable. Care is needed to keep feet in good condition, because in the past loss of feet was not uncommon.

Question 40

Diabetes Treatment​

Answer 40

Type 1 – this is treated with the use of insulin analogues which are manufactured using recombinant DNA technology. Different formulations of insulin can be prepared, so rate of uptake following injection varies. This allows for the best control. Examples of rapid acting insulins are: Actrapid, Humulin S and Novorapid. Insulin isophane is intermediate acting and insulin glargine is long acting. There a different regimes the patient can be put on: pre mixed insulin twice a day (less injections) or basal bonus – long acting and fast/short acting with meals (more injections but better control). It is important to educate the patient on the use of their insulin, as too much use leads to hypoglycaemia. Type 2 – the first line of management is non-pharmacological, involving diet, lifestyle and exercise changes. If this is not sufficient to control the blood glucose, or there is evidence of complications beginning in checks (eg signs of retinopathy on fundoscopy) then a biguanide (metformin) is prescribed. If this is not sufficient to control blood glucose levels then a sulphonylurea is added (eg tolbutamide, gliclazide), and if this is not enough then a third hypoglycaemic agent will be added. The final treatment is insulin therapy

Question 41

Epilepsy Pathophysiology​:

Answer 41

This is abnormal electrical activity in the brain, leading to recurrent unprovoked seizures. The clinical features of the seizure depend on the location of the abnormal discharges and their extent of spread throughout the cortex. The cause of most cases of epilepsy is unknown.

Question 42

Epilepsy Symptoms and signs

Answer 42

A partial seizure only affects one hemisphere. In a simple partial seizure the patient will retain awareness, they are often precursors to a lather seizure. In a complex partial seizure awareness is lost. Frontal lobe – abnormal head movements, swearing, shouting, unusual posturing, repeated head movements Parietal lobe – abnormal sensations, hallucinations, difficultly understanding Temporal lobe – déjà vu, strange taste or smell, rising sensation in stomach, lip smacking, chewing, swallowing Occipital lobe – hallucinations, disturbed vision, nystagmus, eye pain A generalised seizure affects both hemispheres (crosses the corpus callosum) and there are many types. Tonic clonic – tonic is loss of consciousness, body stiffens and falls to the ground. Clonic is limb jerking, loss of bladder control, tongue biting, may have respiratory arrest. There is a post ictal period in this type of seizure Atonic – sudden loss of tone Myoclonic – muscular jerking Absence – unresponsiveness, may be blinking, slight jerking of body and limbs, resembles day dreaming

Question 43

Epilepsy Investigations and outcomes

Answer 43

Clinical diagnosis – eyewitness account of the episodes. EEG may provide evidence to support clinical diagnosis.

Question 44

Epilepsy Progression​:

Answer 44

Status epilepticus is when a seizure has lasted for 5 minutes or more or multiple seizures have continued for 30 minutes where the patient does not regain consciousness between them. This is a medical emergency and requires treatment with diazepam or midazolam. Some patients will require treatment for the rest of their lives to avoid having seizures, whereas others will be be able to keep their epilepsy under control by avoiding triggers. The condition varies from person to person.

Question 45

Epilepsy Treatment

Answer 45

It may be possible to control epilepsy with lifestyle changes – avoiding triggers like alcohol and sleep deprivation. It is usually managed pharmacologically: sodium channel antagonists – phenytoin, carbamazepine and lamotrigine, GABA potentiators – benzodiazepines (diazepam, lorazepam, clonazepam) and barbiturates, calcium channel antagonists and glutamate modulators. Neurosurgical procedures happen in a minority of cases.

Question 46

Gallstones Pathophysiology​

Answer 46

The gallbladder stores bile acids until they are needed. In order to reduce the volume that is needed to store, bile acids are concentrated by the transport of salt and water across the gallbladder epithelium. This concentration process increases the risk of precipitation, leading to gallstone

Question 47

Gallstones Symptoms and signs

Answer 47

Most cases of gallstones do not cause any symptoms. However, if a gallstone moves into the neck of the gall bladder or the biliary tree they can cause very painful biliary colic or obstruction. Pain from gallstones is often worse after eating because the release of CCK cause contraction of the gallbladder. Obstruction to the biliary system causes post hepatic jaundice, so there will be yellowish pigmentation of the skin, conjunctival membranes over the sclerae and other mucus membranes. If there is associated infection of the gallbladder or bile duct then there will symptoms like a raised temperature and feeling generally unwell.

Question 48

Gallstones Investigations and outcomes

Answer 48

Generally a clinical diagnosis – positive Murphy’s sign for an inflamed gall bladder Ultrasounds – visualise gallstones Raised bilirubin levels due to obstruction (jaundice >40) Raised ALP – enzyme in cells lining the biliary tree

Question 49

Gallstones Progression​

Answer 49

If gallstone cause an obstruction, this leads to complications. Acute cholecystitis is inflammation of the gall bladder, and acute cholangitis can also occur which is inflammation of the bile ducts. If the gallstone moves to blocks the pancreatic duct, it can lead to acute pancreatitis. Obstruction can also lead to jaundice

Question 50

Gallstones Treatment​

Answer 50

The treatment depends on how much the symptoms are affecting the patient's life. If the pain is mild and infrequent, then the patient will be given painkillers. However, if the pain is frequent and severe, the patient may have a laparoscopic cholecystectomy to remove the gallbladder. If the gallstones are in the bile duct, an ERCP may be carried out to remove them

Question 51

Heart Failure Pathophysiology​

Answer 51

State in which heart fails to maintain adequate circulation for needs of the body despite adequate filling pressure. Most commonly caused by IHD, hypertension and arrhythmias. More quirky causes include: dilated cardiomyopathy, valvular heart disease, restrictive cardiomyopathy and pericardial disease. Types​: Note: afterload is the pressure on the wall of the left ventricle during ejection. Systolic heart failure= reduced contractility due to increased afterload, and therefore reduced ejection fraction. Leads to thinning of myocardial wall and reduced cardiac output. Diastolic heart failure= reduced filling of heart due to inability to relax adequately, therefore causing a reduced preload and reduced cardiac output. Can also be classified as left/right/congested (L leading to R)

Question 52

Heart Failure Symptoms and signs

Answer 52

Symptoms of left heart failure include: pulmonary oedema, dysphonia, wheeze, paroxysmal nocturnal dyspnoea, displaced apex beat and mitral regurgitation. Symptoms of right heart failure include: peripheral oedema, ascites, hepatomegaly, increased JVP and fatigue.

Question 53

Heart Failure Investigations and outcomes

Answer 53

Brain natriuretic peptide followed by ultrasound of the heart if found to be raised (to support diagnosis). Ultrasound can be used to determine stroke volume, end diastolic volume and ejection fraction. If the person has compensated for their heart failure, X-ray may show cardiomegaly. There may also be signs of pulmonary oedema, from areas of patchy consolidation

Question 54

Heart Failure Progression​

Answer 54

Class increases until breathless on any activity Class 1= no symptoms Class 2= slight limitation of physical activity. Ordinary physical activity results in symptoms. Class 3= marked limitation of physical activity. Less than ordinary physical activity resulting in symptoms, but none at rest Class 4= inability to carry out any activity without symptoms. Symptoms may be present at rest and there is discomfort by doing any level of physical activity.

Question 55

Heart Failure Treatment​

Answer 55

Positive iontropes e.g. cardiac glycosides (digoxin) and beta agonists (dobutamine). These are good for short-term gains. Digoxin works by blocking Na-K-ATPase channel and so blocking sodium uptake into the cell. This causes reversal of the NCX channel, which means more calcium can move into the cell to cause calcium induced calcium release. This means even more calcium is released and there is an increase in force of contraction, overall resulting in an increased heart rate. The rate is slowed by the vagal property activity of cardiac glycosides meaning there is slowing AVN conduction and so slower heart rate. Beta agonists act on B1 adrenoreceptors to increase myocardial contractility. There are then other drugs which decrease the workload of the heart and so can be used for longer term treatment. These include ACEi, calcium channel blockers and diuretics. Beta blockers can also be used, but less commonly. ACEi work by reducing amount of angiotensin 2 being produced, which means there will be less water retained and blood pressure will drop, decreasing afterload and making it easier for the heart to pump. There is also less vasoconstriction, which lowers BP. o Calcium channel blockers work by causing vasodilation Diuretics reduce blood volume (and hence BP) Beta blockers

Question 56

Hypertension Pathophysiology​

Answer 56

Blood pressure of 140/90 or above is classified as hypertension. Treatment begins at 160/100. Most of the time the cause of hypertension is unknown (essential hypertension), but can also be secondary to a discrete identifiable cause (10% of population). The causes include Cushing’s syndrome, Conn’s syndrome, renovascular hypertension and coarctation of the aorta. In essential hypertension it is generally due to high TPR, while cardiac output remains the same.

Question 57

Hypertension Symptoms and signs

Answer 57

Rarely accompanied by symptoms (silent killer), and so usually identified through screening. May occasionally report of headache, light-headedness, vertigo, tinnitus and fainting episodes, however these symptoms may be more to do with the anxiety of having the condition instead of the condition itself.

Question 58

Hypertension Investigations and outcomes

Answer 58

Diagnosis by finding of persistently high resting BP. There should be a full history and physical examination as well as taking account of possible white coat effect on the blood pressure, which can be reduced by taking continual blood pressures over 24 hours.

Question 59

Hypertension Progression​

Answer 59

Increased arterial thickening by smooth muscle hypertrophy in artery walls and accumulation of vascular matrix, leading to loss of compliance and targeted organ damage. This can lead to CVS and CNS morbidity.

Question 60

Hypertension Treatment​

Answer 60

Lifestyle modification and pharmacological agents to cause a decrease in BP by acting on cardiac output and total peripheral resistance. Diuretics, ACEi, B blockers and calcium channel blockers all work to help.

Question 61

IBD Pathophysiology​

Answer 61

Idiopathic condition causing inflammation of the GI tract, often presenting alongside arthritis and psoriasis (and so presumed autoimmune mechanism). Also often linked to genetics, antibiotics, infection, smoking and diet. Trigger include antibiotics, diet, acute infection, NSAIDs, stress and smoking (only detrimental effect in Crohn’s).

Question 62

IBD Symptoms and signs:

Answer 62

Crohns: pernicious anaemia, nausea and vomiting, dyspepsia, small bowel obstruction, anorexia, loose stools, diarrhoea. UC: iron deficiency anaemia from blood lost in stools, rectal bleeding, diarrhoea and abdominal pain.

Question 63

IBD Investigations and outcomes

Answer 63

Colonoscopy, stool analysis, barium radiography, CT scan, capsule endoscopy

Question 64

IBD Progression​

Answer 64

Complications include toxic megacolon, bowel perforation, colorectal carcinoma (however picked up early due to regular testing).

Question 65

IBD Treatment​

Answer 65

Aminosalicylates or corticosteroids (prednisolone) for flare-ups and immunosuppressant therapy for maintenance (methotrexate/azathioprine) and anti-TNF-a Surgery can be done to remove affected bowel, but this is not a cure (rarely full colonectomy, only in precancerous states).

Question 66

Osteoarthritis Pathophysiology

Answer 66

Articular cartilage breakdown of the synovial joint space, leading to decreased joint space, sclerosis, osteophytes and bone cysts, visible on an X-ray. Often due to natural aging process and more common in women and the obese. May be some links to genetics but not currently well understood

Question 67

Osteoarthritis Symptoms and signs

Answer 67

Pain, stiffness on first movement, crepitus, swelling (hard if caused by osteophytes or soft if caused by synovial thickening), muscle thinning around the joint, not being able to move joint as freely

Question 68

Osteoarthritis Investigations and outcomes

Answer 68

Blood tests (to rule out other causes) X-ray MRI (looking for other joint pathologies e.g. knee meniscus tearing) if cannot diagnose by other methods

Question 69

Osteoarthritis Progression​

Answer 69

Progression is dependent on the person affected by the condition. Although there may be pain and loss of function, there will not be any systemic involvement, fever or inflammation as it only affects the joints. Complications include gout (as the changes to the joint make it more likely for crystals to form in the joint space) and chondrocalcinosis (the same pathophysiology as gout but with calcium pyrophosphate crystals).

Question 70

Osteoarthritis Treatment​

Answer 70

Capsaicin painkiller cream, stronger painkillers including tramadol and meptazinol, NSAIDs, steroid injections (for sudden painful attacks or to get through important events such as wedding/holiday) TENS machine (can be borrowed from physiotherapy and then bought from pharmacy) arthroscopic lavage surgery (washing out bits of loose bone from knee, in severe cases, when knee keeps locking etc). Also remember lifestyle modifications including exercise, weight management and reducing strain on the joints (walking stick, low-healed, thick soled shoes). There are some complementary medicines available…

Question 71

Ischaemic heart disease Pathophysiology​

Answer 71

Atheromatous plaques forming in coronary arteries, restricting flow of blood to heart muscle, reducing pumping ability.

Question 72

Ischaemic heart disease Symptoms and signs

Answer 72

Central tightening/crushing pain, which can radiate to the epigastrium, neck, jaw, shoulders and arms. Chest pain is referred to as angina.

Question 73

Ischaemic heart disease Investigations and outcomes

Answer 73

Risk assessment, family history, lifestyle questions and blood test. Further diagnosis may be required, using an MRI scan, CT scan or coronary angiography.

Question 74

Ischaemic heart disease Progression​

Answer 74

Angina → unstable angina Heart attack and heart failure may also occur.

Question 75

Ischaemic heart disease Treatment​

Answer 75

Reduce risk factors by stopping smoking, getting DM under control, reducing hypertension, reducing cholesterol and getting exercise.

Question 76

Peptic ulcer disease Pathophysiology​

Answer 76

Defect in gastric mucosa into muscularis mucosa layer, most commonly seen in the first part of the duodenum and lesser curve of the stomach. Causes include H.Pylori infection and chronic NSAID use. Can also be caused by Zollinger-Ellison (gastrin secreting tumour of B cells causing more stomach acid production by parietal cells) and Crohn’s disease in more unusual presentations.

Question 77

Peptic ulcer disease Symptoms and signs

Answer 77

Main symptoms are epigastric pain, bleeding and weightloss. Burning epigastric pain will be worse when hungry and relieved after eating for duodenal ulcers. Other symptoms include nausea, vomiting, anorexia, haematemesis/melena.

Question 78

Peptic ulcer disease Investigations and outcomes

Answer 78

Diagnosis presumed by symptoms alone. Confirmed by endoscopy and barium contrast X-rays. Diagnosis of H. Pylori by urea breath test direct culture from biopsy stool antigen testing.

Question 79

Peptic ulcer disease Progression​

Answer 79

Complications include GI bleeding (if ulcer erodes back into blood vessels such as gastroduodenal artery), Perforation into peritoneum leading to peritonitis, Gastric outlet obstruction (narrowing of pyloric canal by scarring and swelling of gastric antrum and duodenum).

Question 80

Peptic ulcer disease Treatment

Answer 80

Triple therapy of PPI (omeprazole), H2 antagonist (cimetidine) and antibiotic (clarythromycin/amoxicillin if infection present.) Stop taking NSAIDs.

Question 81

Rheumatoid arthritis Pathophysiology​

Answer 81

Autoimmune synovial inflammation and joint destruction. Swelling and inflammation of the synovium causes nerve ending to be irritated (causing pain) and the capsule will swell due to the accumulation of fluid in the joint. When swelling goes down, the capsule will remain stretched and mean the joint is unstable and so can become deformed. Most commonly affects women between 40 and 50 years old, but can affect adults at any stage

Question 82

Rheumatoid arthritis Symptoms and signs

Answer 82

Joint pain and swelling, stiffness, tiredness, depression, irritability, anaemia, flu-like symptoms (generally unwell), weight loss, rheumatoid nodules.

Question 83

Rheumatoid arthritis Investigations and outcome

Answer 83

Blood tests to measure inflammation- either ESR or CRP to show inflammation. Rheumatoid factor can also be produced by immune system and detected in the blood. X-rays will show damage to the joints before symptoms are felt and so may x-ray all possible joints.

Question 84

Rheumatoid arthritis Progression​

Answer 84

75% of people will have flare-ups, joint pain and swelling 20% will have very mild RA 5% will develop extensive disability Blood tests and x-rays can be used to assess prognosis.

Question 85

Rheumatoid arthritis Treatment​

Answer 85

Reduce alcohol intake, stop smoking, reduce coffee intake and increase vitamin C intake. Hydrotherapy, exercise and comfortable footwear all make a difference to symptom management. Drug treatments include painkillers and NSAIDs, DMARDs (methotrexate, anti-TNF, rituximab) and corticosteroids such as prednisolone. Methotrexate is given once a week and competitively and reversibly inhibits DHFR to inhibit DNA synthesis and reduce T cell activation and suppression of intracellular adhesion molecules produced by T cells, reducing joint destruction. Anti-TNF (infliximab) suppresses TNF, which is part of the immune response responsible for joint destruction Rituximab deplete B cells

Question 86

Thrombo-embolic disorders Pathophysiology​

Answer 86

Venous thromboembolism or pulmonary embolism. Virchow’s triad: Changes in vessel wall (blockage/tearing/Vasculitis/chemotherapy damage) - o Changes in blood constituents (oestrogen/smoking/pregnancy/dehydration) Changes in flow rate- turbulent/stasis (long flights/inactivity)

Question 87

Thrombo-embolic disorders Symptoms and signs

Answer 87

DVT: Pain and swelling in leg PE: Sudden breathlessness, chest pain, sudden collapse

Question 88

Thrombo-embolic disorders Investigations and outcomes

Answer 88

D- dimer blood test detects pieces of blood clot that have broken down in the bloodstream. The more present, the more likely it is that there is a blood clot in your vein. However, not reliable after operation, injury or pregnancies as blood clot fractions can increase then anyway. Doppler ultrasound scans of distal veins required to confirm DVT.

Question 89

Thrombo-embolic disorders Progression​

Answer 89

DVT can progress to PE

Question 90

Thrombo-embolic disorders Treatment​

Answer 90

Low molecular weight heparin initially, for use until warfarin action kicks in, in addition to compression stockings. Reduce likelihood of getting another DVT by stopping contraceptive pill/HRT, not smoking, eating healthily, taking regular exercise and maintaining a healthy weight. If you are going on a long distance journey, should drink lots of water, perform simple leg exercises and take regular short walking breaks.

Question 91

Thyroid disease Pathophysiology​

Answer 91

Hypothyroidism: Autoimmune destruction of TSH receptors/follicles (Hashimoto’s disease) or thyroidectomy. Hyperthyroidism: Autoimmune stimulation of TSH receptors (Grave’s disease), toxic thyroid adenoma, struma ovarii or ectopic thyroid tissue productio

Question 92

Thyroid disease Symptoms and signs

Answer 92

Hypothyroidism: Bradycardia, alopecia, lethargy, weakness, loss of memory, cold intolerance, constipation, deep voice, dry flaky skin. Hyperthyroidism: tachycardia, heat intolerance, diarrhoea, weight loss, osteoporosis, cardiomyopathy, bulging eyes (exophthalmos)

Question 93

Thyroid disease Investigations and outcomes

Answer 93

Hypothyroidism: Low T3/4 and high TSH Hyperthyroidism: High T3/4 and low TSH

Question 94

Thyroid disease Progression

Answer 94

Hypothyroidism: low thyroxine leading to high cholesterol, leading to build up of fat in the arteries, leading to restriction of the flow of blood, and possible cardiovascular disease, goitre (in both), myxoedema coma (thyroid hormones become so low that can cause confusion, hypothermia and drowsiness) ``` Hyperthyroidism: Thyroid eye disease: NOSPECS No signs, no symptoms Only signs, no symptoms Sensitivity to light Proptosis Extra ocular muscle involvement Corneal ulceration Sight loss ``` Hyperthyroidism can also lead to a thyroid storm where there is sudden over activation and a flare-up of symptoms, leading to rapid heartbeat, high temperature, diarrhoea and vomiting, yellow eyes and skin, agitation and confusion and loss of consciousness.

Question 95

Thyroid disease Treatment​

Answer 95

Hypothyroidism: Levothyroxine (oral T4) Hyperthyroidism: Carbimazole (prevent iodine incorporation to thyroglobulin/removal of thyroid). Treat thyroid eye disease with steroids

Question 96

Vasovagal faints Pathophysiology​

Answer 96

Fainting is due to temporary loss of blood flow to the brain, which causes you to fall to the floor in an attempt to allow gravity to help re-perfuse the brain. In most cases due to autonomic nervous system, which normally regulates automatic body functions including heart rate and blood pressure. When the heartbeat flows or pauses it can interrupt the blood supply to the brain, resulting in vasovagal syncope

Question 97

Vasovagal faints Symptoms and signs

Answer 97

Feeling weak and unsteady before passing out for a short amount of time. May feel suddenly clammy, nauseous, confused, light headed or blurred vision prior to fainting. Comes on with strain (coughing/sneezing) or standing (postural tachycardia syndrome). Triggers include: standing for long time, heat, seeing blood, having blood drawn, fear of bodily injury, straining.

Question 98

Vasovagal faints Investigations and outcomes

Answer 98

Should phone ambulance if doesn’t regain consciousness in 2 minutes, as may worry about stroke. Often diagnosed by ruling out other causes of fainting: History, blood pressure and cardiac exam for any arrhythmias,ECG for irregular heart beats, carotid sinus tests and blood test for anaemia. Table tilt test can be used to check if blood pressure and heart rhythms change dependent on postural changes.

Question 99

Vasovagal faints Progression

Answer 99

Unconsciousness itself does not cause any damage, however may hurt self when falling so good to think about when you may have them and prepare/sit down.

Question 100

Vasovagal faints Treatment

Answer 100

If you feel like you are about to faint then lie down and raise legs or put head between knees until feel better. If due to cardio inhibitory form, then can give pacemaker. Can prescribe medications such as CNS stimulants, fludrocortisone and SSRIs for all forms.