Definition Urticaria (hives): transient, pruritic, erythematous wheals due to mast cell degranulation and histamine release. Duration of individual lesions: <24 hours. Key Types Type Duration Common Triggers Acute <6 weeks Foods, drugs, viral infections Chronic >6 weeks Idiopathic, autoimmune, thyroid disease Physical Triggered by physical stimuli Cold, heat, pressure, exercise (cholinergic) 💡 High-Yield Tip: Chronic urticaria is usually idiopathic or autoimmune, not allergic. Common Triggers Drugs: penicillins, NSAIDs, aspirin, opiates Foods: nuts, shellfish, eggs Infections: viral URTI, hepatitis Insect bites/stings Idiopathic Exam Trap: If urticaria occurs immediately after a drug or food, think IgE-mediated hypersensitivity → risk of anaphylaxis. Clinical…
Author: Dr Ben
Definition Erysipelas is an acute bacterial infection of the upper dermis and superficial lymphatics, producing a well-demarcated, raised area of inflammation. Causative Organisms Streptococcus pyogenes (Group A strep) – most common. Less commonly: Group B, C, G streptococci. 💡 Distinction: Erysipelas → almost always streptococcal. Cellulitis → can be strep or staph. Risk Factors Breaks in skin barrier (trauma, eczema, tinea pedis, ulcers). Chronic oedema, lymphatic obstruction. Diabetes, obesity. Immunosuppression. Clinical Features Abrupt onset with fever, chills, malaise. Bright red, swollen, warm plaque with raised and sharply demarcated borders. Commonly affects face and lower limbs. May see lymphangitic streaking and…
Definition Cellulitis is an acute bacterial infection of the dermis and subcutaneous tissue, usually spreading rapidly with poorly demarcated edges. Common Causative Organisms Streptococcus pyogenes (Group A strep) – most common. Staphylococcus aureus – especially when abscess or purulence is present. MRSA – consider in recurrent, hospital-acquired, or IV drug users. 💡 PLAB Gem: If cellulitis has pus, boils, or abscesses → think Staph aureus.If diffuse and spreading with lymphangitis → think Streptococcus pyogenes. Risk Factors Skin break: trauma, ulcer, surgery, insect bite. Lymphatic obstruction, venous insufficiency. Diabetes mellitus. Immunosuppression. 💡 Exam Tip: In PLAB, diabetics with foot ulcers are…
Status epilepticus (SE) is a medical emergency defined as a prolonged seizure lasting more than 5 minutes or recurrent seizures without full recovery of consciousness in between. Prompt recognition and treatment are crucial to prevent long-term neurological damage and complications, such as brain injury or death. As a PLAB 1 candidate, it’s important to be familiar with the key steps in the management of SE, as this is a high-yield topic. Classification of Status Epilepticus: Convulsive Status Epilepticus (CSE): Characterized by generalized tonic-clonic seizures. Non-convulsive Status Epilepticus (NCSE): Presenting with altered mental status or subtle seizures, often without visible motor…
Dementia is a progressive neurodegenerative syndrome marked by a decline in cognition that interferes with daily functioning. It is not a normal part of aging and deserves thorough clinical evaluation and intervention. With over 55 million people globally affected, dementia represents one of the leading causes of disability among older adults (World Health Organization). 2. Classification and Prevalence Dementia is an umbrella term comprising several subtypes, each with distinct pathology and clinical features: Subtype Estimated Prevalence Key Features Alzheimer’s Disease (AD) ~60–70% Gradual memory loss, language and visuospatial deficits Vascular Dementia (VaD) ~10–20% Stepwise decline, often post-stroke Lewy Body Dementia…
Myocardial infarction (MI), commonly known as a heart attack, occurs due to an acute obstruction of coronary blood flow, leading to ischemia and necrosis of myocardial tissue. It is a medical emergency requiring prompt recognition and intervention to reduce morbidity and mortality. This article provides a comprehensive yet clinically practical approach to MI, covering pathophysiology, ECG changes, biomarkers, and guideline-based management strategies. Further Reading: European Society of Cardiology (ESC) Guidelines on Myocardial Infarction 2. Pathophysiology of Myocardial Infarction The pathophysiology of MI follows a series of events leading to irreversible myocardial necrosis: Plaque Rupture: Disruption of an atherosclerotic plaque within…
Electrocardiography (ECG) is an essential tool in clinical practice, used for diagnosing arrhythmias, myocardial infarctions, electrolyte imbalances, and various cardiac conditions. Despite its ubiquity, ECG interpretation requires a structured approach to ensure accurate diagnosis and appropriate clinical management. This article provides a detailed yet practical guide for medical professionals, breaking down ECG interpretation into a stepwise approach. It includes key considerations for rhythm analysis, conduction abnormalities, ischemic changes, and electrolyte disturbances, with reference to relevant guidelines. Further Reading: NICE Guidelines on ECG Interpretation 2. Basic Principles of ECG An ECG records the electrical activity of the heart as it propagates…
Arrhythmias are disturbances in cardiac rhythm that can range from benign to life-threatening. This article provides a comprehensive comparison of Atrial Fibrillation (AF), Atrial Flutter, Supraventricular Tachycardia (SVT), Ventricular Tachycardia (VT), Ventricular Fibrillation (VF), and Torsades de Pointes (TdP), including their ECG findings, causes, symptoms, and management. 2. Overview of Arrhythmias Arrhythmia ECG Characteristics Origin Heart Rate Clinical Features Atrial Fibrillation (AF) Irregularly irregular rhythm, no P waves, fibrillatory waves Atria 100-175 bpm Palpitations, stroke risk, dyspnea, fatigue Atrial Flutter Sawtooth flutter waves, regular rhythm Atria ~150 bpm Palpitations, dizziness, heart failure symptoms Supraventricular Tachycardia (SVT) Narrow QRS, P waves…
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, characterized by irregular, rapid atrial electrical activity leading to ineffective atrial contraction. It significantly increases the risk of stroke, heart failure, and mortality. 2. Classification of Atrial Fibrillation Type Duration Characteristics Paroxysmal AF <7 days (self-terminating) Spontaneously resolves within 48 hours – 7 days Persistent AF >7 days Requires cardioversion for termination Long-standing Persistent AF >12 months May not respond to rhythm control Permanent AF Persistent despite attempts at cardioversion Rate control is the primary strategy 3. Causes and Risk Factors Category Common Causes Cardiac Causes Hypertension, ischemic heart disease,…
Infective Endocarditis (IE) is a life-threatening infection of the heart’s endocardium, most commonly affecting heart valves. It can lead to valvular destruction, heart failure, embolic events, and multi-organ complications. Early recognition and treatment are crucial to reduce morbidity and mortality. 2. Classification of Infective Endocarditis Type Description Acute IE Rapid onset, highly virulent organisms (e.g., Staphylococcus aureus), aggressive progression Subacute IE Indolent course, less virulent organisms (e.g., Streptococcus viridans), occurs on pre-existing valve disease Native Valve Endocarditis (NVE) Infection on natural heart valves Prosthetic Valve Endocarditis (PVE) Infection on prosthetic heart valves (early: <1 year post-surgery, late: >1 year post-surgery)…
Hypertension, commonly known as high blood pressure, is a chronic medical condition characterized by elevated blood pressure levels. It significantly increases the risk of cardiovascular diseases, including stroke, myocardial infarction, heart failure, and kidney disease. Effective management of hypertension involves accurate diagnosis, lifestyle modifications, pharmacological interventions, and regular monitoring to prevent complications. 2. Diagnosis and Classification of Hypertension (A) Blood Pressure Measurement Accurate measurement of blood pressure (BP) is crucial for diagnosis. The American Heart Association emphasizes proper techniques to ensure reliable readings, such as correct arm positioning and using appropriately sized cuffs. citeturn0search7 (B) Classification by Guidelines NICE Guidelines…
Congenital heart diseases (CHDs) are structural abnormalities of the heart present at birth. They range from simple, asymptomatic defects to severe, life-threatening conditions requiring urgent intervention. Advances in fetal screening, surgical correction, and catheter-based interventions have improved survival rates, allowing many CHD patients to reach adulthood. 2. Classification of Congenital Heart Diseases CHDs are classified based on cyanosis, shunting patterns, and structural defects. (A) Classification by Cyanosis Category Description Examples Acyanotic CHDs (Left-to-Right Shunts) Increased pulmonary blood flow ASD, VSD, PDA, AVSD Cyanotic CHDs (Right-to-Left Shunts) Deoxygenated blood enters systemic circulation Tetralogy of Fallot, Transposition of Great Arteries (B) Classification…