## Cardiovascular System: Key Conditions for PLAB Part 1

The Cardiovascular System is a high-yield topic for PLAB 1, covering common and critical conditions. Understanding their presentation, investigation, and initial management is crucial.

## Ischaemic Heart Disease (IHD)

IHD encompasses conditions caused by reduced blood flow to the heart muscle. Angina is chest pain due to myocardial ischaemia, typically relieved by rest or nitrates. Stable angina is predictable, while unstable angina is new-onset, worsening, or occurring at rest. Myocardial Infarction (MI) is myocardial cell death due to prolonged ischaemia.

• Acute Coronary Syndrome (ACS) includes unstable angina, NSTEMI, and STEMI.
• Symptoms: Central crushing chest pain, radiating to arm/jaw, dyspnoea, sweating, nausea.
• Investigations: ECG (ST elevation in STEMI, ST depression/T wave inversion in NSTEMI/unstable angina), Troponin (elevated in MI), full blood count, U&Es, lipids.
• Management (ACS): Immediate MONA (Morphine, Oxygen, Nitrates, Aspirin +/- Clopidogrel). STEMI requires urgent reperfusion (PCI or thrombolysis).

## Heart Failure

Heart failure is the inability of the heart to pump sufficient blood to meet metabolic demands. It can be due to systolic dysfunction (reduced ejection fraction) or diastolic dysfunction (impaired filling).

• Causes: IHD, hypertension, valvular heart disease, arrhythmias.
• Symptoms: Progressive dyspnoea (exertional, orthopnoea, PND), fatigue, peripheral oedema.
• Signs: Elevated JVP, crackles, S3 gallop, pitting oedema, hepatomegaly.
• Investigations: BNP (elevated), Echocardiogram (confirms diagnosis, assesses ejection fraction and valvular function), CXR (cardiomegaly, pulmonary oedema).
• Management: Lifestyle modifications, ACE inhibitors, Beta-blockers, Mineralocorticoid Receptor Antagonists (e.g., Spironolactone) for mortality benefit. Diuretics for symptom control.

## Hypertension

Hypertension is persistently elevated blood pressure, a major risk factor for IHD, stroke, and kidney disease. Diagnosis requires repeated elevated readings, often confirmed with 24-hour Ambulatory Blood Pressure Monitoring (ABPM).

• Target BP: Generally <140/90 mmHg (or <135/85 mmHg for home readings).
• Management: Lifestyle changes (diet, exercise, reduced salt/alcohol). Pharmacological treatment often starts with ACE inhibitors (or ARBs) for under 55s not of black African/Caribbean origin, or Calcium Channel Blockers for others. Diuretics (thiazide-like) are also common first-line or add-on.

## Respiratory System Overview

The respiratory system facilitates gas exchange. Key conditions encountered in PLAB Part 1 include obstructive lung diseases (Asthma, COPD), restrictive lung diseases (ILD), infections (Pneumonia, Bronchiectasis), and acute emergencies (Pneumothorax, Pulmonary Embolism).

## Obstructive Lung Diseases

• Asthma: A chronic inflammatory airway disease characterised by reversible airway obstruction, bronchial hyperresponsiveness, and variable respiratory symptoms (wheeze, cough, dyspnoea, chest tightness). Triggers include allergens, exercise, cold air. Management involves short-acting beta-agonists (SABA) for relief and inhaled corticosteroids (ICS) as a preventer. Severe exacerbations may require oral steroids and nebulised bronchodilators.
• Chronic Obstructive Pulmonary Disease (COPD): A progressive, irreversible airway obstruction, primarily caused by smoking. Symptoms include chronic cough, sputum production, and progressive dyspnoea. Diagnosis is confirmed by spirometry showing FEV1/FVC ratio < 0.7 post-bronchodilator. Management focuses on smoking cessation, bronchodilators (LABA, LAMA), inhaled corticosteroids (in some cases), and oxygen therapy for severe hypoxaemia.

## Acute Respiratory Conditions

• Pneumonia: An acute infection of the lung parenchyma. Symptoms include cough, fever, dyspnoea, pleuritic chest pain. Diagnosis by chest X-ray (CXR) showing consolidation. Management is with antibiotics, guided by severity (e.g., CURB-65 score).
• Pneumothorax: Air in the pleural space, leading to lung collapse. Can be spontaneous (primary or secondary) or traumatic. Symptoms include sudden onset pleuritic chest pain and dyspnoea. Diagnosis by CXR. Small pneumothoraces may be observed; larger ones or symptomatic cases require aspiration or chest drain insertion. A tension pneumothorax is a medical emergency requiring immediate needle decompression.
• Pulmonary Embolism (PE): Blockage of pulmonary arteries, usually by a thrombus from the deep veins (DVT). Risk factors include immobility, surgery, malignancy, OCP. Symptoms vary but include sudden dyspnoea, pleuritic chest pain, haemoptysis, syncope. Diagnosis often involves D-dimer (if low probability) and CT Pulmonary Angiogram (CTPA). Management is with anticoagulation.

## Other Important Conditions

• Pleural Effusion: Abnormal fluid accumulation in the pleural space. Causes can be transudative (e.g., heart failure, liver cirrhosis) or exudative (e.g., pneumonia, malignancy, PE). Presents with dyspnoea and pleuritic pain. Diagnosis by CXR, ultrasound, and pleural fluid aspiration.
• Lung Cancer: Often presents late with persistent cough, haemoptysis, weight loss, chest pain, or dyspnoea. Smoking is the primary risk factor. Investigations include CXR, CT chest, and biopsy for histological diagnosis.

## Gastrointestinal System: Key Concepts & Conditions

The gastrointestinal (GI) system is a common focus in PLAB 1, covering a wide range of conditions from common dyspepsia to acute abdomen. Understanding key symptoms, investigations, and management is crucial for diagnosis and patient care.

Common Symptoms & Red Flags

Dyspepsia (indigestion) is a frequent complaint. Red flags that necessitate urgent investigation include: unexplained weight loss, dysphagia (difficulty swallowing), odynophagia (painful swallowing), persistent vomiting, GI bleeding (haematemesis, melaena, PR bleeding), anaemia, and an abdominal mass. These symptoms often warrant an urgent endoscopy (upper GI or colonoscopy).

Gastro-Oesophageal Reflux Disease (GORD)

Caused by reflux of stomach acid into the oesophagus. Common symptoms are heartburn, acid regurgitation, and sometimes dysphagia. Management typically involves lifestyle modifications (e.g., weight loss, avoiding trigger foods, elevating head of bed) and pharmacological agents, primarily Proton Pump Inhibitors (PPIs) like omeprazole or lansoprazole.

Peptic Ulcer Disease (PUD)

Ulcers in the stomach or duodenum, frequently caused by _Helicobacter pylori_ (H. pylori) infection or NSAID use. Symptoms include epigastric pain, dyspepsia, and sometimes GI bleeding. H. pylori is diagnosed via urea breath test, stool antigen test, or biopsy during endoscopy. Treatment for H. pylori involves eradication therapy (a PPI plus two antibiotics for 7-14 days), or stopping NSAIDs and prescribing PPIs for NSAID-induced ulcers.

Inflammatory Bowel Disease (IBD)

Comprises Crohn's Disease and Ulcerative Colitis (UC). Both are chronic, relapsing-remitting inflammatory conditions of the GI tract.

• Crohn's: Can affect any part of the GI tract from mouth to anus, with transmural inflammation, skip lesions, and granulomas. Symptoms include abdominal pain, diarrhoea, weight loss, and perianal disease.
• UC: Affects only the colon and rectum, with mucosal inflammation and a continuous pattern. Symptoms typically include bloody diarrhoea and tenesmus.

Diagnosis for both is primarily via colonoscopy with biopsy. Management involves aminosalicylates, corticosteroids, immunosuppressants, and biologics.

Coeliac Disease

An autoimmune condition triggered by gluten ingestion in genetically predisposed individuals, leading to small bowel villous atrophy. Symptoms include chronic diarrhoea, bloating, abdominal pain, weight loss, fatigue, and anaemia. Diagnosis involves screening with anti-tissue transglutaminase (anti-TTG) antibodies and confirmation with an endoscopic small bowel biopsy showing villous atrophy. Management is a lifelong, strict gluten-free diet.

Acute Pancreatitis

Acute inflammation of the pancreas, most commonly caused by gallstones or alcohol abuse. Symptoms include severe, sudden onset epigastric pain often radiating to the back, nausea, and vomiting. Diagnosis is based on clinical presentation, elevated serum amylase or lipase (at least three times the upper limit of normal), and imaging (e.g., CT abdomen). Management is supportive, involving aggressive IV fluid resuscitation, analgesia, and nil by mouth.

## Neurology Revision for PLAB Part 1

Neurology is a high-yield topic covering conditions affecting the brain, spinal cord, and peripheral nerves. Understanding common presentations and initial management is crucial.

## Headaches

Migraine: Characterised by unilateral, throbbing pain, often with aura (visual disturbances), nausea, vomiting, photophobia, and phonophobia. Acute treatment includes NSAIDs, triptans (e.g., sumatriptan). Prophylaxis for frequent attacks (e.g., beta-blockers, topiramate).

Tension Headache: Bilateral, pressing/tightening, mild-moderate intensity, no associated features. Managed with simple analgesics.

Cluster Headache: Severe, unilateral periorbital pain, associated with ipsilateral autonomic features (e.g., lacrimation, ptosis, rhinorrhoea). Acute treatment: 100% oxygen, subcutaneous triptans.

Red Flags: Always consider secondary causes for new, severe, or atypical headaches. Look for thunderclap headache, new onset >50 years, focal neurological deficits, papilloedema, fever, neck stiffness, or headache worsening with Valsalva.

## Stroke and Transient Ischaemic Attack (TIA)

Stroke: Acute neurological deficit due to cerebrovascular disease. Ischaemic stroke (85%) due to arterial occlusion; haemorrhagic stroke (15%) due to bleeding. Symptoms depend on the affected area (e.g., facial droop, arm weakness, speech disturbance - FAST).

Acute Management: Immediate CT head to rule out haemorrhage. If ischaemic and within 4.5 hours of symptom onset (and no contraindications), thrombolysis (alteplase) may be considered. Aspirin 300mg is given within 24 hours (if no haemorrhage and not thrombolysed).

TIA: Transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischaemia, without acute infarction. Symptoms resolve within 24 hours (usually minutes). High risk of subsequent stroke; requires urgent investigation (e.g., carotid Doppler, ECG, MRI brain) and antiplatelet therapy (e.g., aspirin + clopidogrel for 21 days, then clopidogrel monotherapy).

## Seizures and Epilepsy

Epilepsy: Recurrent unprovoked seizures.

Generalized Seizures: Affect both hemispheres. Tonic-clonic involves tonic (stiffening) and clonic (jerking) phases, often with a post-ictal state (confusion, drowsiness). Absence seizures are brief lapses of consciousness.

Focal Seizures: Originate in one hemisphere, can be with or without impaired awareness. Symptoms vary based on location.

Status Epilepticus: Seizure lasting >5 minutes or multiple seizures without regaining consciousness between them. A medical emergency. Initial management: ABCDE, IV lorazepam (or buccal midazolam) followed by IV phenytoin or levetiracetam.

## Parkinson's Disease

A progressive neurodegenerative disorder due to dopamine deficiency in the substantia nigra.

Classic Triad: Bradykinesia (slowness of movement), rigidity (cogwheel or lead-pipe), and resting tremor (pill-rolling). Other features include postural instability, masked facies, shuffling gait. Management involves dopamine agonists (e.g., ropinirole) or levodopa.

## Multiple Sclerosis (MS)

A chronic inflammatory demyelinating disease of the central nervous system. Characterised by episodes of neurological dysfunction (relapses) followed by recovery (remissions).

Common Symptoms: Visual disturbances (e.g., optic neuritis - painful unilateral vision loss), sensory symptoms (numbness, tingling), motor weakness, ataxia, fatigue, bladder dysfunction. Diagnosis involves MRI brain/spinal cord showing demyelinating plaques and CSF analysis (oligoclonal bands). Acute relapses treated with high-dose corticosteroids.

## Diabetes Mellitus

Diabetes Mellitus (DM) is a chronic metabolic disorder characterized by elevated blood glucose levels. Type 1 DM results from autoimmune destruction of pancreatic beta cells, leading to absolute insulin deficiency. It typically presents in childhood or adolescence with acute symptoms like polyuria, polydipsia, polyphagia, and weight loss. Type 2 DM is characterized by insulin resistance and relative insulin deficiency, often associated with obesity and a strong genetic predisposition, typically presenting in adulthood.

Diagnosis of DM is based on:

• HbA1c ≥ 48 mmol/mol (6.5%)
• Fasting plasma glucose ≥ 7.0 mmol/L
• Random plasma glucose ≥ 11.1 mmol/L (with symptoms)
• Oral Glucose Tolerance Test (OGTT) 2-hour plasma glucose ≥ 11.1 mmol/L

Acute complications include Diabetic Ketoacidosis (DKA) (Type 1, characterized by hyperglycaemia, ketonaemia, metabolic acidosis) and Hyperosmolar Hyperglycaemic State (HHS) (Type 2, characterized by severe hyperglycaemia, hyperosmolarity, dehydration, without significant ketosis). Chronic complications affect microvascular (retinopathy, nephropathy, neuropathy) and macrovascular (CAD, stroke, PVD) systems.

## Thyroid Disorders

Hyperthyroidism (e.g., Graves' disease) presents with weight loss, palpitations, heat intolerance, tremor, anxiety, and sometimes exophthalmos and pretibial myxoedema. Diagnosis involves low TSH and high free T4/T3. Treatment includes anti-thyroid drugs (carbimazole, propylthiouracil), radioiodine, or surgery.

Hypothyroidism (e.g., Hashimoto's thyroiditis) presents with weight gain, fatigue, cold intolerance, constipation, bradycardia, and dry skin. Diagnosis involves high TSH and low free T4. Treatment is lifelong levothyroxine replacement.

## Adrenal Gland Disorders

Addison's disease (primary adrenal insufficiency) results from adrenal cortex destruction, leading to cortisol and aldosterone deficiency. Features include fatigue, weight loss, hyperpigmentation, hypotension, hyponatraemia, and hyperkalaemia. Diagnosis involves short synacthen test. Treatment is steroid replacement.

Cushing's syndrome results from prolonged exposure to high cortisol levels. Features include central obesity, moon face, buffalo hump, purple striae, hypertension, hyperglycaemia, and proximal myopathy. Diagnosis involves dexamethasone suppression tests or 24-hour urinary free cortisol.

Conn's syndrome (primary hyperaldosteronism) is characterized by hypertension and hypokalaemia due to excessive aldosterone production, often by an adrenal adenoma. Diagnosis involves aldosterone-to-renin ratio.

## Calcium Metabolism

Primary Hyperparathyroidism is characterized by elevated parathyroid hormone (PTH) leading to hypercalcaemia. Symptoms are often vague but can include 'stones, bones, abdominal groans, and psychiatric overtones'.

## Obstetrics & Gynaecology Revision

Pre-eclampsia

A multi-system disorder unique to pregnancy, characterised by new-onset hypertension (BP ≥140/90 mmHg on two occasions, 4 hours apart) and proteinuria (≥0.3g/24h) after 20 weeks gestation. Can also present with end-organ dysfunction (e.g., headache, visual disturbance, epigastric pain, abnormal LFTs/platelets) without proteinuria.

• Risk factors: Nulliparity, previous pre-eclampsia, chronic hypertension, diabetes, multiple pregnancy, renal disease, autoimmune conditions.
• Management: Close monitoring, anti-hypertensives (e.g., labetalol, nifedipine), magnesium sulfate for seizure prophylaxis in severe cases, and definitive treatment is delivery of the baby and placenta.

Postpartum Haemorrhage (PPH)

Defined as blood loss of ≥500ml within 24 hours of birth (primary PPH) or ≥1000ml for severe PPH. Secondary PPH occurs 24 hours to 12 weeks postpartum.

• Causes (4 Ts): Tone (uterine atony - most common), Trauma (vaginal/cervical tears), Tissue (retained placental tissue), Thrombin (coagulopathy).
• Management: ABCDE approach, call for help, bimanual uterine compression, IV fluids, uterotonics (e.g., oxytocin, carboprost, misoprostol), identify and treat cause.

Ectopic Pregnancy

Implantation of a fertilised ovum outside the uterine cavity, most commonly in the fallopian tube. A medical emergency.

• Symptoms: Amenorrhoea, abdominal pain (often unilateral), and vaginal bleeding. May present with shoulder tip pain (diaphragmatic irritation from haemoperitoneum) or collapse.
• Diagnosis: Positive pregnancy test, transvaginal ultrasound showing empty uterus and adnexal mass/fluid, serial hCG levels (rise slower than expected).
• Management: Expectant (if stable, low hCG), medical (methotrexate), or surgical (laparoscopic salpingectomy/salpingostomy).

Polycystic Ovary Syndrome (PCOS)

A common endocrine disorder characterised by a combination of:

• Oligo/anovulation (irregular or absent periods)
• Clinical or biochemical hyperandrogenism (hirsutism, acne, alopecia, elevated testosterone)
• Polycystic ovaries on ultrasound (12 or more follicles 2-9mm in one ovary, or ovarian volume >10ml).
• Diagnosis: Requires 2 out of 3 Rotterdam criteria.
• Management: Lifestyle modification (diet, exercise), COCP for menstrual regulation and hirsutism, anti-androgens, metformin for insulin resistance, clomiphene/letrozole for fertility.

Endometriosis

Presence of endometrial-like tissue outside the uterus, causing a chronic inflammatory reaction.

• Symptoms: Chronic pelvic pain (cyclical, often worsening during menstruation), dysmenorrhoea (severe period pain), dyspareunia (painful intercourse), dyschezia (painful bowel movements), infertility.
• Diagnosis: Clinical suspicion, imaging (ultrasound, MRI) may show endometriomas, but laparoscopy with biopsy is the gold standard.
• Management: Pain relief (NSAIDs), hormonal therapies (COCP, progestogens, GnRH analogues), surgical excision of lesions.

## Neonatal Jaundice

Neonatal jaundice is common, affecting ~60% of term babies. It's caused by increased bilirubin levels.

• Physiological jaundice: Appears >24 hours of age, peaks at 3-5 days, resolves by 14 days (term) or 21 days (preterm). Usually unconjugated.
• Pathological jaundice: Appears <24 hours of age, rapidly rising bilirubin, prolonged jaundice (>14/21 days), or associated with other symptoms. Causes include haemolysis (e.g., ABO incompatibility, G6PD deficiency), infection, biliary atresia (conjugated hyperbilirubinemia).
• Management: Monitor bilirubin levels. Phototherapy is the primary treatment for significant unconjugated hyperbilirubinemia, converting bilirubin into water-soluble isomers. Exchange transfusion for severe, rapidly rising levels or signs of acute bilirubin encephalopathy.

## Respiratory Conditions

• Bronchiolitis: Viral infection (RSV most common) of lower airways, typically in infants <2 years. Presents with coryzal symptoms followed by cough, tachypnoea, subcostal/intercostal recession, and wheeze/crackles. Management is supportive (hydration, oxygen if sats <92%). No routine bronchodilators or steroids.
• Croup (Laryngotracheobronchitis): Viral infection causing inflammation of the larynx, trachea, and bronchi. Characterised by a barking cough, inspiratory stridor, and hoarseness. Worse at night. Management: single dose of oral dexamethasone, humidified air.

## Child Protection

• Recognising and responding to signs of child abuse or neglect is crucial.
• Indicators: Unexplained injuries (bruises, fractures, burns), inconsistent history, delayed presentation, poor hygiene, developmental delay due to neglect, behavioural changes.
• Action: Always consider child abuse in suspicious circumstances. Document observations accurately. If there are immediate safety concerns, contact social services or police. Discuss concerns with a senior paediatrician or safeguarding lead.

## Growth and Development

• Growth charts: Used to monitor weight, height, and head circumference. Failure to thrive (FTT) is inadequate weight gain or weight loss, often crossing two major centile lines downwards. Causes can be organic (e.g., malabsorption, cardiac disease) or non-organic (e.g., inadequate feeding, neglect).
• Developmental milestones: Assess gross motor, fine motor, speech & language, and social & emotional domains. Delays warrant investigation (e.g., hearing screen, genetic testing).

## Immunisations

• Routine childhood immunisations are vital for preventing infectious diseases. Follow the UK immunisation schedule.
• Contraindications are rare: confirmed anaphylaxis to a previous dose or vaccine component. Minor illnesses (e.g., common cold) are NOT contraindications.

## Psychiatric Assessment Fundamentals

A thorough psychiatric assessment includes history taking (presenting complaint, history of present illness, past psychiatric history, past medical history, drug history, family history, personal history including social and developmental aspects), and a mental state examination (MSE). The MSE covers appearance, behaviour, speech, mood, affect, thought form, thought content (delusions, obsessions, suicidal ideation), perception (hallucinations), cognition (orientation, memory, attention), and insight. Risk assessment for self-harm, suicide, and harm to others is paramount.

## Common Psychiatric Disorders

Depression

Characterised by low mood, anhedonia (loss of pleasure), and fatigue for at least two weeks, along with other symptoms like changes in appetite/sleep, psychomotor agitation/retardation, poor concentration, feelings of worthlessness/guilt, and suicidal thoughts. Management often involves antidepressants (SSRIs first-line) and psychological therapies (CBT).

Anxiety Disorders

Includes Generalised Anxiety Disorder (GAD) (excessive worry for >6 months), Panic Disorder (recurrent unexpected panic attacks), Social Anxiety Disorder, and Phobias. Symptoms include physical (palpitations, sweating, tremor) and psychological (apprehension, irritability). Treatment involves CBT and SSRIs.

Psychotic Disorders (e.g., Schizophrenia)

Defined by a distortion of reality, featuring positive symptoms (hallucinations, delusions, thought disorder) and negative symptoms (alogia, avolition, anhedonia, affective flattening). Diagnosis requires symptoms for >1 month. Antipsychotics are the mainstay of treatment, often with significant side effects (e.g., extrapyramidal symptoms - EPS, metabolic syndrome).

Bipolar Disorder

Characterised by episodes of both mania/hypomania and depression. Mania involves elevated mood, increased energy, reduced need for sleep, grandiosity, racing thoughts, and risky behaviour. Treatment includes mood stabilisers (lithium, valproate, lamotrigine) and antipsychotics.

## Delirium vs. Dementia

Delirium is an acute, fluctuating disturbance of attention and cognition, often caused by an underlying medical condition (e.g., infection, drugs). It is a medical emergency. Dementia is a chronic, progressive decline in cognitive function, not due to delirium or other psychiatric disorders. Common types include Alzheimer's and Vascular Dementia.