@About this App@Contributers@DeveloperACTH (Adrenocorticotropic hormone)AFP (Alpha-fetoprotein) TestingAIDS Dementia Complex (HIV)AIDS HIV InfectionAPGAR Scoring (Children)APTT and CoagulationAbacavirAbataceptAbbreviated Mental Test Score (AMTS)AbciximabAbdominal Aortic AneurysmAbdominal paracentesis for ascitesAbducent NerveAbetalipoproteinaemiaAbnormal Vaginal bleedingAcamprosateAcanthocytosisAcanthosis NigricansAcarboseAccelerated Idioventricular RhythmAcetazolamideAcetylcholine Receptor AntibodiesAcetylcholinesterase inhibitorsAchalasiaAchilles Tendon ruptureAchondroplasia (Children)AciclovirAcid maltase deficiency (Pompe disease)Acne RosaceaAcne VulgarisAcoustic Neuroma (Schwannoma)Acrodermatitis enteropathica (Children)Acromegaly and GiantismAcromio-clavicular jointActinomyces israeliAction PotentialActivated CharcoalActrapid (Insulin)Acute Abdominal Pain - Acute PeritonitisAcute Acalculous CholecystitisAcute Anaphylactoid ReactionsAcute AnaphylaxisAcute Angle Closure GlaucomaAcute AppendicitisAcute Bacterial MeningitisAcute BronchitisAcute CholangitisAcute CholecystitisAcute Colonic Pseudo-obstructionAcute Coronary Syndrome (ACS) GeneralAcute Coronary Syndrome (ACS) NSTEMI USAAcute Coronary Syndrome (ACS) STEMIAcute Coronary Syndrome (Cardiac Troponins)Acute Coronary Syndrome Grace scoreAcute DeliriumAcute Disc lesionsAcute Disseminated EncephalomyelitisAcute Diverticulitis - Diverticular diseaseAcute Dystonic ReactionAcute EncephalitisAcute Eosinophilic PneumoniaAcute EpiglottitisAcute Exacerbation of COPDAcute HepatitisAcute HydrocephalusAcute HypotensionAcute InflammationAcute Intermittent Porphyria (AIP)Acute Interstitial nephritisAcute Kidney Injury (AKI)Acute Limb IschaemiaAcute Liver FailureAcute Lymphoblastic Leukaemia (ALL)Acute MastoiditisAcute MonoarthritisAcute Myeloid Leukaemia (AML)Acute MyocarditisAcute PancreatitisAcute Pelvic Inflammatory DiseaseAcute PericarditisAcute Phase reactantsAcute PorphyriasAcute Promyelocytic LeukaemiaAcute Respiratory Distress Syndrome (Adults)Acute Retroviral Syndrome (HIV)Acute RhabdomyolysisAcute Rheumatic feverAcute Rotator cuff tearAcute Severe AsthmaAcute Severe ColitisAcute SinusitisAcute Stroke Assessment (ROSIER&NIHSS)Acute TonsilitisAcute Urinary RetentionAcute and Chronic GoutAcute and Chronic Heart FailureAcute on Chronic Liver Disease DecompensationAcutely Ill PatientAdalimumabAddenbrooke's Cognitive Examination-Revised (ACER)Addison Disease (Adrenal Insufficiency)AdefovirAdenosineAdenosine deaminase deficiencyAdhesive Capsulitis (Frozen Shoulder)Adjustment - Anxiety disordersAdrenal AntibodiesAdrenal PhysiologyAdrenaline (Epinephrine)AdrenoleukodystrophyAdrenomyeloneuropathyAdult Onset Still's DiseaseAfrican Trypanosomiasis (Sleeping sickness)Age related macular degenerationAicardi syndromeAir EmbolismAlbuminAlbumin-Protein Creatinine Ratio (PCR)Alcohol AbuseAlcohol Withdrawal (Delirium Tremens)Alcoholic (Steato)HepatitisAlcoholic KetoacidosisAldosterone PhysiologyAlendronate (Alendronic acid)AlfacalcidolAlkaline phosphatase (ALP)Alkalinisation of urineAlkaptonuriaAllergic Bronchopulmonary AspergillosisAllogeneic stem cell transplantationAllopurinolAlogliptin (Vipidia)AlopeciaAlpha FetoproteinAlpha ThalassaemiaAlpha subunit (ASU) of TSHAlpha-1 Antitrypsin (AAT) deficiencyAlport's SyndromeAlteplaseAltitude sicknessAluminium and Magnesium AntacidsAlveolar Gas EquationAlzheimer disease (Dementia)AmantadineAmenorrhoeaAmerican Trypanosomiasis (Chagas Disease)AmilorideAmino acidsAminoglycosidesAminophyllineAminosalicylatesAmiodaroneAmiodarone and Thyroid diseaseAmitriptylineAmlodipineAmmonia EncephalopathyAmnestic syndromesAmoebiasis (Entamoeba histolytica)AmoxicillinAmphetamine toxicityAmphotericin BAmpicillinAnaemia of Chronic DiseaseAnagrelideAnakinraAnal CancerAndexanet alfaAndrogen insensitivity syndromeAneurysmsAngina bullosa haemorrhagicaAngiodysplasiaAngiomyolipomaAngioneurotic OedemaAngiotensin Converting Enzyme InhibitorsAngiotensin Converting enzyme (ACE)Angular Stomatitis - CheilitisAnion GapAnkle and Foot fractures and InjuriesAnkle-Brachial pressure Index (ABPI)Ankylosing spondylitisAnorexia NervosaAntacid medicationAntepartum haemorrhageAnterior Horn Cell diseasesAnterior circulationAnti Dementia DrugsAnti-Cyclic Citrullinated Peptide (CCP) AntibodyAnti-D immunoglobulinAnti-Hu antibodiesAnti-OKT3 antibodiesAnti-RNP AntibodyAnti-Yo antibodiesAnti-neutrophilic cytoplasmic antibodies (ANCA)Antibiotics for Abdominal InfectionsAnticholinergic BurdenAnticholinergic syndromeAnticipationAnticoagulation and AntithromboticsAntidiuretic hormone (Vasopressin)Antigen presenting cellsAntimicrobial ChoicesAntimuscarinic drugsAntiphospholipid syndromeAntithrombin III deficiency (AT3)Aorta anatomyAortic DissectionAortic Regurgitation (Incompetence)Aortic SclerosisAortic StenosisAortoenteric fistulaApathetic thyrotoxicosisApixabanAplastic anaemiaApomorphineAppendix Cancer TumoursApproach to Assessing Sick ChildApproach to child with Acute GastroenteritisApproach to child with respiratory DistressArnold Chiari malformationArrhythmogenic Right ventricular CardiomyopathyArtemisininsArterial Blood gas analysisArterial Pulse assessmentArterial blood gas samplingArterial vs Venous vs Other Leg UlcersArteriovenous malformationsArtery of Percheron strokeArtery-to-artery embolic strokeArtesunateAsbestos Related Lung diseaseAscites Assessment and ManagementAspergillomaAspergillus fumigatusAspirinAspirin Salicylates toxicityAssessing Abdominal PainAssessing BreathlessnessAssessing Chest PainAssessing FallsAsteatotic eczemaAsthmaAstigmatismAstrocytomasAsystoleAtaxia TelangiectasiaAtazanavirAtenololAtherosclerosisAtopic Eczema or Atopic DermatitisAtorvastatinAtracuriumAtrial Ectopic beatsAtrial Fibrillation (Chemical cardioversion)Atrial Natriuretic Peptide (ANP)Atrial fibrillation (AF)Atrial flutterAtrial myxomaAtrial septal defect (ASD)Atrioventricular nodal reentrant tachycardiaAtropine SulfateAutoantibodiesAutoimmune Haemolytic anaemia (AIHA)Autoimmune HepatitisAutonomic neuropathyAutosomal DominantAutosomal Dominant Polycystic kidney diseaseAutosomal RecessiveAzathioprineAzithromycinB lymphocytesBRCA genes (Familial Breast Cancer)Bacillus anthracisBacillus cereus poisoningBackpain / BackacheBaclofenBacteriaBacteroides fragilisBalanitis (Adults)Balanitis (Children)Balkan endemic nephropathy (BEN)Balsalazide (Aminosalicylate)Barrett's oesophagusBartonellaBartters syndromeBasal Cell Carcinoma (BCC)Basic Fracture managementBasilar artery thrombosisBecker Muscular dystrophyBeclometasoneBeer PotomaniaBehavioural and Psychological Symptoms of DementiaBehcet's syndromeBell's palsyBendroflumethiazide (Bendrofluazide)Benign Paroxysmal Positional Vertigo (BPPV)Benign Prostatic HyperplasiaBenign recurrent intrahepatic cholestasisBenzodiazepine ToxicityBenzodiazepinesBenzylpenicillin Sodium (Penicillin G)Berg Balance ScaleBeriplexBerylliosisBeta AgonistsBeta Blocker toxicityBeta ThalassaemiaBeta-2 MicroglobulinBeta-lactamasesBetahistine (Serc)BezafibrateBiceps ruptureBilateral adrenalectomyBiliary atresiaBilirubinBiochemical Lab valuesBisacodylBisoprololBisphosphonatesBladder CancerBladder StonesBleedingBleeding disordersBleeding due to DrugsBleomycinBlindness - global causesBlood products - Packed cells blood transfusionBlood Products - CryoprecipitateBlood Products - Fresh Frozen PlasmaBlood Products - PlateletsBlood film interpretationBlood gas valuesBloody DiarrhoeaBlotting Techniques: Gel ElectrophoresisBone Marrow TransplantationBone disease Lab resultsBone metabolism RANK RANKL OPG pathwayBone scintigraphy (Bone scan)Bordetella pertussis - Whooping coughBorrelia burgdorferiBorrelia recurrentisBotulismBrachial neuritis (neuralgic amyotrophy)Brachial plexus anatomyBrachial plexus and associated injuryBrain AbscessBrain Anatomy and functionBrain MRIBrain Natriuretic Peptide (BNP)Brain PhysiologyBrain Tumours (Cancer)Brainstem anatomyBranchial cleft cystBreast CancerBreast FibroadenomaBretyliumBroad complex TachycardiaBromocriptineBronchial adenomaBronchiectasisBronchiolitisBronchoscopyBrown-Sequard syndromeBrucellaBrugada syndromeBudd-Chiari syndromeBudesonideBuerger disease (Thromboangiitis obliterans )Bulbar vs Pseudobulbar palsyBulimia NervosaBullous PemphigoidBumetanideBunionsBuprenorphineBupropionBurkholderia cepaciaBurkitt's lymphomaBurnsBusulphan (Busulfan)ByssinosisC reactive protein (CRP)CADASILCARASILCHADS2 - CHA2DS2-VASc scoreCMV retinitisCNS fungal InfectionsCNS infectionsCSF RhinorrhoeaCT Head Basics (Stroke)CT Pulmonary angiogram (CTPA)CT imaging basics for StrokeCURB 65 scoreCabergolineCaecal VolvulusCaisson Disease - Decompression sicknessCalcitoninCalcitriol (1,25 Dihydroxycholecalciferol)Calcium Chloride or GluconateCalcium PhysiologyCalcium Pyrophosphate Deposition (Pseudogout)Calcium ResoniumCalcium channel blockers toxicityCalot's triangleCampylobacterCancer of Unknown PrimarCandesartanCandidiasisCannabis toxicityCapecitabineCapnocytophaga canimorsusCapnographyCapreomycinCaptopriCarbamazepineCarbapenemase-producing EnterobacteriaceaeCarbimazoleCarbon monoxide poisoningCarcinoembryonic antigen (CEA)Carcinoid Heart DiseaseCarcinoid Tumour SyndromeCarcinoma of the Bile DuctCarcinoma of the GallbladderCardiac Amyloid heart diseaseCardiac Anatomy and PhysiologyCardiac Catheter ablationCardiac InfectionsCardiac MRICardiac Resynchronisation Therapy (CRT) PacemakerCardiac Valve replacementCardioembolic strokeCardiogenic Pulmonary OedemaCardiogenic shockCardiology - History TakingCardiology Exam ListCardiology ExaminationCardiology Valves SummaryCardiopulmonary bypassCarmustineCarotid Artery anatomyCarotid Body TumourCarotid EndarterectomyCarotid Sinus SyncopeCarotid StentingCarotid artery DissectionCarotid sinus massageCarpal tunnel syndromeCarvedilolCase 01 Sudden weaknessCase 02 Loss of speechCase 03 Adult male weak legsCase 04 High calciumCase 05 High Potassium and heart failureCase 06 High calcium and weight lossCase 07 Weak eyesCase 08 Weak faceCase 09 A cause of DeliriumCase 10 Older patient presenting post strokeCase 11 Young patient with acute headacheCase 20 Young patient with acute headacheCase 21 HypoglycaemiaCase 22Case 23 Old man with tremorCase 24 Cancer and weakCase 99 (Acute breathlessness)Case TemplateCat Scratch DiseaseCataractCatheter Related Urinary Tract infection UTICatheter related Blood stream infectionCatheter related UTICauda equina syndromeCaudate NucleusCauses of Airway ObstructionCauses of Avascular Necrosis of Femoral headCauses of Sore throatCauses of WeaknessCavernous angiomas (Cavernomas)Cavernous sinusCavernous sinus thrombosisCefaclorCefalexinCefotaximeCeftazidimeCeftriaxoneCefuroximeCelecoxibCell Response to InjuryCellular Anatomy and PhysiologyCellulitisCentral Cord SyndromeCentral Retinal Vein Occlusion (CRVO)Central Retinal artery Occlusion (CRAO)Central Venous line InsertionCentral pontine myelinolysisCephalosporinsCerebellar Anatomy Physiology Signs DiseaseCerebellar HaemorrhageCerebellar StrokeCerebral Amyloid angiopathy (CAA)Cerebral AneurysmsCerebral AngiitisCerebral Atrophy vs HydrocephalusCerebral CortexCerebral MetastasesCerebral PalsyCerebral PerfusionCerebral Salt WastingCerebral Venous Sinus thrombosisCerebral arteritisCerebral microbleedsCervical Cancer screeningCervical Spine injuryCervical cancerCervical spondylosisCetirizineChancroidCharcot Foot Syndrome (CFS)Charcot Marie Tooth (CMT) diseaseChediak Higashi syndromeChest Abdomen anatomyChest X Ray #1Chest X Ray InterpretationChest drain InsertionChlamydia - Chlamydophila pneumoniaeChlamydia psittaciChlamydia trachomatisChlorambucilChloramphenicolChlordiazepoxideChloroquineChlorphenamine(Chlorpheniramine)ChlorpromazineCholangiocarcinomaCholera (Vibrio cholera)Cholestatic JaundiceCholesteatomaCholesterol - LipidsCholinergic crisis-syndromeChondrocalcinosisChorea - BallismusChoreoacanthocytosisChromosome instability syndromesChronic BronchitisChronic HepatitisChronic InflammationChronic Inflammatory Demyelinating polyneuropathyChronic Interstitial NephritisChronic Kidney Disease (CKD)Chronic Lymphocytic leukaemia (CLL)Chronic Myeloid Leukaemia (CML)Chronic Obstructive Pulmonary Disease (COPD)Chronic PancreatitisChronic PeritonitisChronic Radiation EnteritisChronic Urinary RetentionChronic Vision Uni-Bilateral loss (Blindness)Chronic and recurrent MeningitisChronic liver diseaseChronic mucocutaneous candidiasisChronic stable anginaChylomicronsCiclosporinCimetidineCinacalcetCiprofloxacinCirrhosisCisplatinCitalopramCladribineClarithromycinCleft lip or palateClindamycinClopidogrelClostridium botulinumClostridium difficileClostridium perfringensClostridium tetani - TetanusClotrimazole creamClotting pathwaysClozapineCo Careldopa (Sinemet)Co-Amoxiclav (Augmentin)Co-Beneldopa (Madopar)Co-codamolCo-trimoxazoleCoagulopathyCoal Worker's PneumoconiosisCoarctation of the Aorta (CoA aortopathy)Cocaine abuseCocaine induced chest painCocaine toxicityCoccidioidomycosisCodeineCoeliac diseaseCogan SyndromeColchicineCold Agglutinin Disease (CAD/AIHA)CollagenColloid cyst in the third ventricleColloidsColonic (Large bowel) ObstructionColonoscopyColorectal cancerColorectal polypsColposcopyComa managementCombined Oral contraceptive pill (COCP)Common Peroneal Nerve (CPN)Common variable immunodeficiencyComparing Rheumatoid and OsteoarthritisComplementComprehensive Geriatric Assessment (CGA)Confirming DeathCongenital Acyanotic Heart Disease (Children)Congenital Adrenal hyperplasiaCongenital Complete Heart BlockCongenital Cyanotic Heart Disease (Children)Congenital HypothyroidismCongenital Talipes Equinovarus - ClubfootConstipationConstrictive PericarditisContact allergic dermatitisContinuous Positive Airways Pressure (CPAP)Continuous ambulatory peritoneal dialysisContraceptionConus Medullaris syndromeCor PulmonaleCoronary artery bypass graft surgeryCoronavirus SARS-CoV-2 COVID 19Corticobasal degeneration (Dementia)Corticosteroid-related psychosisCorticosteroidsCorynebacterium diphtheriaeCotard delusionCoxiella BurnetiiCranial nerves and examinationCraniopharyngiomaCreatinine ClearanceCremation forms (UK)Creutzfeldt Jakob disease (Dementia)Crimean-Congo haemorrhagic feverCritical illness neuromuscular weaknessCrohn's diseaseCroupCryptococcus neoformans infectionsCryptogenic Fibrosing AlveolitisCryptogenic Organising Pneumonia (COP-BOOP)CryptosporidiosisCrysal arthritisCrystalloidsCushing diseaseCushing syndromeCutaneous LeishmaniasisCyanide toxicityCyanosis - Central and PeripheralCyclizineCyclo-oxygenase (COX) enzymesCyclophosphamideCycloserineCys leukotriene receptor antagonistsCystic FibrosisCystinosisCystinuriaCytokinesCytomegalovirus infectionsD DimerDNA and RNA short notesDNA replicationDabigatranDalteparinDandy Walker syndromeDantroleneDapagliflozinDarier's DiseaseDarunavirDeQuervain's thyroiditisDeath Certificates (UK)Deep brain stimulationDeep vein thrombosis (DVT)Dehydration PhysiologyDelayed Puberty CriteriaDemeclocyclineDementia with Lewy bodiesDementiasDemyelinating DiseasesDengue FeverDenosumab (Prolia)Dental AnatomyDentatorubral pallidoluysian atrophyDepressionDermatitis HerpetiformisDermatology termsDermatomesDermatomyositisDermoid cystsDesferrioxamineDesmopressin (DDAVP)Desogestrel (Progestogen Only Pill)Developmental Dislocation (Dysplasia) of the HipDevelopmental MilestonesDexamethasoneDiGeorge syndrome (thymic aplasia)Diabetes Insipidus (Cranial and Nephrogenic)Diabetes Mellitus Type 1Diabetes Mellitus Type 1 and DKA (children)Diabetes Mellitus Type 2Diabetes Mellitus in pregnancyDiabetes on the wardDiabetic Autonomic Neuropathy (DAN)Diabetic Ketoacidosis (DKA) AdultsDiabetic Ketoacidosis (DKA) with SGLT2 InhibitorsDiabetic NephropathyDiabetic RetinopathyDiabetic amyotrophyDiabetic footDiamond-Blackfan anaemiaDiamorphineDiaphragmatic disordersDiarrhoeaDiazepamDidanosine (ddI)DiethylstilbestrolDifferentials causes of Foot DropDifferentials of ABCDifferentials of Generalised lymphadenopathyDifferentials of Painful thighDifferentials of XXXDiffuse Oesophageal spasmDiffuse large B-cell lymphomaDiffusion CapacityDigoxinDigoxin ToxicityDihydrocodeineDilated cardiomyopathyDiltiazemDiphtheriaDipyridamoleDischarges against adviceDiscoid lupus erythematosus (DLE)Disease templateDiseases with associated cancersDislocation Sternoclaivcular jointDisopyramideDisseminated Intravascular Coagulation (DIC)Distributive ShockDisulfiram (Antabuse)DobutamineDog BitesDog Bites HandDominant R wave in V1DomperidoneDonepezil (Aricept)DonovanosisDopamine HydrochlorideDopamine agonistsDown's syndrome (Trisomy 21)DoxapramDoxazosin (Cardura)DoxepinDoxorubicin (Adriamycin)DoxycyclineDrivingDrowningDrug Induced Parkinson diseaseDrug Reaction Eosinophilia Systemic Symptoms DRESSDrug TemplateDrug Toxicity - clinical assessmentDrug Toxicity with Specific AntidotesDrug induced Lupus ErythematosusDrug induced liver diseaseDrugsDrugs ListDrugs to Avoid in Acute Renal failureDrugs to avoid ElderlyDrugs to avoid in Liver failureDry and Wet GangreneDual X-ray absorptiometry (DEXA)Duchenne muscular dystrophyDulaglutide GLP-1 agonistDuloxetineDuodenal Atresia (Children)Dupuytrens contractureDysenteryDysphagiaECG - Acute Coronary SyndromeECG - Acute ST Elevation Myocardial InfarctionECG - Atrial fibrillationECG - Atrial flutterECG - BasicsECG - Broad complex tachycardia (possible VT)ECG - Brugada syndromeECG - Causes of a Dominant R wave in V1ECG - Early Repolarisation vs STEMIECG - First degree AV BlockECG - Heart BlockECG - HyperkalaemiaECG - InterpretationECG - Ischaemic Heart DiseaseECG - Left Axis DeviationECG - Left Bundle Branch Block LBBBECG - Left Ventricular HypertrophyECG - Low Voltage ComplexesECG - Narrow complex tachycardiaECG - Normal appearanceECG - Pathological Q wavesECG - QT intervalECG - Right Axis DeviationECG - Right Bundle Branch Block RBBBECG - ST-T T waves changesECG - Supraventricular tachycardia ECG - The QRS complexECG - Tutorial from Queens UniversityECG - Ventricular fibrillationECG - Ventricular tachycardiaECG - Wolff Parkinson White syndrome (WPW)ECG - short PR intervalECG - sinus pauseECG - tall R wave V1ENT Exam - Assessing hearingENT infectionsEbola Virus DiseaseEbstein anomalyEchinocytesEchocardiogramEcstasy toxicityEctopia lentis (subluxation of the lens)Ectopic PregnancyEctropionEculizumabEdoxaban (Lixiana)Edward syndrome (trisomy 18 syndrome)Efavirenz (Sustiva) EFVEhlers-Danlos syndromesEhrlichiosisEikenella corrodensEisenmenger's syndrome (Children)Elbow fractures and InjuriesElectrical injuryEloquent brainEmergency DrugsEmphysemaEmpty sella syndromeEmtricitabine (Emtriva) FTCEnalaprilEnd of Life Care PrescribingEndocarditis and StrokeEndocrinology Lab valuesEndometrial (Uterine) CancerEndometriosisEndoscopic Retrograde Cholangiopancreatography XEndothelinsEnfuvirtideEnoxaparin Sodium (Clexane-Lovenox)EnoximoneEntacaponeEnterococciEnteropathic SpondyloarthritisEnzyme inducers and inhibitorsEosinophilic granulomatosis (Churg Strauss)EpendymomaEpidural HaematomaEpidural abscessEpilepsy - General ManagementEpilepsy - Idiopathic Generalised EpilepsyEpilepsy - Mesial temporal lobe epilepsyEpilepsy - Post TraumaticEpilepsy in PregnancyEpiscleritisEpistaxisEplerenoneEponymous brainstem strokesEpstein-Barr Virus infectionEquivalent doses of OpiatesErb PalsyErgocalciferol (Calciferol)Erlotinib (Tarceva)Erysipelothrix rhusiopathiaeErythema MultiformeErythema NodosumErythrocyte Sedimentation rate (ESR)ErythrocytesErythrodermic PsoriasisErythromycinEscherichia coliEscitalopramEsomeprazoleEssential Thrombocythaemia (ET)Essential TremorEtanerceptEthambutolEthanolEthanol toxicityEthylene glycol toxicityEtomidateEtravirine (intelence) ETREwing sarcomaExenatide (Byetta) GLP1 agonistExercise stress testExploding head syndromeExtradural haematomaExtrapyramidal symptomsExtrinsic Allergic alveolitis (Hypersensitivity)Eye infectionsEzetimibeFabry diseaseFacial NerveFacioscapulohumeral muscular dystrophyFactor V Leiden DeficiencyFaecal CalprotectinFahr syndromeFailure to thrive or Faltering growthFamilial Adenomatous polyposis (FAP)Familial AmyloidosisFamilial HypercholesterolaemiaFamilial Mediterranean Fever (FMF)Familial hypocalciuric hypercalcaemia (FHH)Family Tree (Pedigree)FamotidineFanconi AnaemiaFanconi SyndromeFat embolismFatigue - CausesFatty acidsFebrile seizuresFelodipine (Dihydropyridine)Femoral HerniaFemoral triangleFemur fractures and InuriesFentanyl - FentanilFerritinFerrous Fumarate - Gluconate - SulphateFetal Alcohol SyndromeFetal circulationFever - Pyrexia of unknown origin (FUO PUO)Fever in a travellerFibratesFibrinogenFibromuscular dysplasiaFibromyalgiaFidaxomicinFinasteride (5 alpha-reductase inhibitor)First SeizureFitz-Hugh Curtis SyndromeFlail ChestFlecainide AcetateFlexor sheath infection (flexor tenosynovitis)FlucloxacillinFluconazoleFlucytosineFludrocortisoneFluid balances statusFlumazenil (Annexate - Romazicon)FluoxetineFocal Segmental Glomerulosclerosis (FSGS)Foix-Alajouanine syndromeFolate (Folic) acidFolate deficiencyFolinic acid (Leucovorin)FomepizoleFondaparinuxFood borne diseaseFoscarnet SodiumFosfomycinFosphenytoinFoster Kennedy SyndromeFournier's gangreneFracture TemplateFractured ClavicleFractured Neck of FemurFractured Pubic RamusFractured ScapulaFractured Shaft FemurFractured Tibia and FibulaFractures Shaft HumerusFractures in ChildrenFractures of Upper humerusFragile X syndromeFrailtyFraser guidelines and Gillick CompetenceFree RadicalsFriedreich's AtaxiaFrontotemporal dementiaFull or Complete Blood Count (FBC CBC)FungiFurosemide (Frusemide)Fusidic acidFusobacteria - Tropical ulcerFusobacteriumG protein-coupled receptorsGP Emergency Drugs CarriedGabapentinGalactorrhoeaGalantamineGamete intra-fallopian tube transfer (GIFT)Gamma Glutamyl Transferase (GGT)Gamma hydroxy butyrate (GHB) toxicityGanciclovir - ValganciclovirGardner syndromeGardnerella vaginalisGas GangreneGastric (MALT) LymphomaGastric CancerGastric Outlet obstruction (pyloric stenosis)GastrinomaGastro Intestinal Stromal Tumours (GIST)Gastro-Oesophageal Reflux (Adult GORD)Gastro-Oesophgeal Reflux (Paediatrics GORD)GastroenteritisGastroenterology Exam ListsGastroenterology ExaminationGastroenterology HistoryGastroenterology assessment - JaundiceGastrointestinal anatomy and physiologyGastrointestinal perforationGastrostomy (PEG) tubesGaucher's diseaseGene componentsGenetic DiseasesGentamicinGiardiasisGilbert's syndromeGingival (Gum) hyperplasia-hypertrophyGitelman's syndromeGlasgow Blatchford ScoreGlasgow Coma scaleGlatiramer acetate (Copaxone)GlibenclamideGliclazideGlimepirideGlipizideGlobus PallidusGlomerulonephritisGlossitisGlucagonGlucagonomaGlucose 6 phosphate dehydrogenase deficiencyGlucose Tolerance TestGlutamateGlycated HaemoglobinGlyceryl Trinitrate (GTN)Glycogen storage diseasesGlycolysis_Krebs_Electron_Transport_ChainGlycopyrronium BromideGoitreGolfer's ElbowGolimumab (Simponi)Goodpasture's syndrome (Anti GBM disease)Goserelin (Zoladex)Gradenigo's syndromeGrades of RecommendationGram StainGranuloma annulareGranulomatosis with Polyangitis GPA (Wegener)Graves DiseaseGriseofulvinGrowth Hormone DeficiencyGuillain Barre SyndromeGum hypertrophyGuthrie test New Born blood spotGynaecological History TakingGynaecomastiaHAS-BLED scoreHIV and Post-Exposure Prophylaxis (PEP)HIV and Pre-exposure prophylaxisHIV associated nephropathy (HIVAN)HIV disease AssessmentHTLV-1 Associated myelopathyHaematemesisHaematology Examination - SplenomegalyHaematology Lab valuesHaematuria Mild to SevereHaemodialysisHaemoglobinsHaemolysisHaemolytic AnaemiaHaemolytic Uraemic syndromeHaemolytic disease of the newbornHaemophilia AHaemophilia BHaemophilus aegyptiusHaemophilus ducreyiHaemophilus influenzaeHaemophilus parainfluenzaeHaemopoiesisHaemorrhagic TransformationHaemorrhagic strokeHaemorrhoids (Piles)Hairy Cell LeukaemiaHairy LeukoplakiaHallervorden-Spatz disease (PKAN)HaloperidolHamman-Rich syndromeHand foot and mouth diseaseHand fractures and InjuriesHantavirus infectionsHartmann's solution (Ringer's lactate)Hartnup disease*Hashimoto's (Steroid responsive) EncephalopathyHashimoto's thyroiditisHbA1cHead (Brain) InjuryHead and Neck CancersHeadache - Analgesic overuseHeadache - Assessing Acute and SevereHeadache - Basilar MigraineHeadache - ClusterHeadache - Low CSF pressureHeadache - MigraineHeadache - TensionHeadaches - GeneralHearing aidsHeat StrokeHelicobacter pyloriHelvetica Spotted feverHemicraniectomyHenoch-Schonlein purpuraHeparin - GeneralHeparin - Low Molecular Weight HeparinHeparin - Unfractionated HeparinHeparin-induced thrombocytopenia (HIT)Hepatic EncephalopathyHepatitis AHepatitis BHepatitis CHepatitis DHepatitis EHepatocellular CarcinomaHepatorenal syndromesHereditary ElliptocytosisHereditary HaemochromatosisHereditary Haemorrhagic TelangiectasiaHereditary Spastic ParaparesisHereditary SpherocytosisHereditary angio-oedemaHereditary neuropathy with pressure palsiesHereditary non polyposis coli (Lynch syndrome)Herpes GestationisHerpes SimplexHerpes Simplex Encephalitis (HSV)Herpes VirusesHerpes Zoster Ophthalmicus (HZO) ShinglesHerpes simplex keratitis (HSK)Heyde syndromeHiatus herniaHiccups (Singultus)High Dose Dexamethasone Suppression TestHip pain in childrenHirschsprung disease (congenital megacolon)Hirsuitism XXXHistonesHistoplasmosisHodgkin LymphomaHolt-Oram syndromeHolter monitor (tape) 24-72 hHomocystinuriaHookwormHorner's syndromeHospital acquired Pneumonia (NICE 139)Human albumin solution (HAS)Human prion diseasesHumeral fractures and injuriesHunter's syndrome (MPS-2)Huntington ChoreaHurler's syndrome (MPS-1)Hydatid disease (Echinococcus)Hydatidiform moleHydralazineHydrocortisoneHydrogen BondsHydrops fetalisHydroxocobalaminHydroxocobalamin - Cyanocobalamin (B12)HydroxychloroquineHydroxyurea-HydroxycarbamideHyoscine (Buscopan)Hyper IgM syndromeHyperbaric Oxygen therapyHypercalcaemiaHyperglycaemic Hyperosmolar State (HHS)Hyperinsulinaemic-euglycemic therapy (HIET)HyperkalaemiaHyperkalaemic and Hypokalaemic Periodic ParalysisHypermagnesaemiaHypernatraemiaHyperphosphataemia (High phosphate)HyperprolactinaemiaHypersensitivity reactionsHypertensionHypertension in PregnancyHypertriglyceridaemia (HTG)Hypertrophic cardiomyopathy (HCM - HOCM)Hyperventilation SyndromeHyperviscosity syndromeHypocalcaemiaHypoglycaemiaHypogonadism (Female)Hypogonadism (male)HypokalaemiaHypokalaemic Periodic ParalysisHypomagnesaemiaHyponatraemiaHypoparathyroidismHypophosphataemia (Low phosphate)Hypopituitarism (Pituitary Failure)HypospadiasHypothermiaHypothyroidismHypovolaemic or Haemorrhagic ShockIL-12 receptor deficiencyIV ImmunoglobulinIbandronic acid (Bisphosphonate)IbuprofenIcatibantIdiopathic Intracranial hypertensionIdiopathic Parkinson diseaseIdiopathic Pulmonary FibrosisIgA Nephropathy (Berger's disease)Images - Spot diagosesImatinib mesylateImipenem (Primaxin) with CilastinImmune Reconstitution SyndromeImmune(Idiopathic) Thrombocytopenic Purpura (ITP)Immunoglobulin G4-related disease (IgG4-RD)ImpetigoImplantable cardioverter defibrillator (ICD)Impulse control disordersInclusion Body MyositisIncubation periodsIndapamideIndinavir (IND)Infection screening in Septic patientInfections and their Microbial causeInfectious MononucleosisInfective ConjunctivitisInfective EndocarditisInfertilityInfliximabInfluenzaInguinal HerniaInitial Trauma AssessmentInjury Severity Score (ISS)Insomnia - sleep issuesInsulinInsulinomaInterferon BetaIntermittent ClaudicationInternal CapsuleInternuclear OphthalmoplegiaInterpreting HaematinicsInterstitial KeratitisIntestinal obstruction (Children)Intra Aortic Balloon PumpIntraabdominal abscessIntracerebral Haemorrhage (ICH) ScoreIntracranial HypertensionXIntravenous Iron Replacement (Ferrous)Intraventricular haemorrhage (neonates)Intubation and Mechanical VentilationIntussusception (Adults)Intussusception (Children)Iodine deficiency GoitreIpratropium Bromide (Atrovent)IrbesartanIron SaltsIron deficiency AnaemiaIron toxicityIrritable bowel syndromeIschaemic ColitisIschaemic StrokeIschaemic heart diseaseIsoniazidIsoprenalineIsosorbide DinitrateIsosorbide mononitrateIsotretinoin (Accutane)Ispaghula Husk (Fybogel)IvabradineJansen DiseaseJanus kinase 2Jervell and Lange-Nielsen syndromeJob Syndrome (Hyper IgE syndrome)Jugular Venous Pressure (JVP)Junctional TachycardiaJuvenile DermatomyositisJuvenile Idiopathic arthritis (Stills Disease)Juvenile Myoclonic epilepsy (JME)Kallmann's syndromeKaposi sarcoma (KS)Karnofsky performance status scaleKawasaki diseaseKennedy SyndromeKeratoconusKernicterusKetamineKetoconazoleKlebsiella pneumoniaKlinefelter Syndrome (Children)Klumpke palsyKnee fractures and InjuriesKoebner phenomenonKugelberg Welander syndromeKwashiorkorL-Thyroxine (T4)Labetalol (Trandate)Labyrinthitis - Vestibular NeuronitisLactateLactate dehydrogenase (LDH)Lactic acidosisLactobacillus acidophilusLactose IntoleranceLactuloseLady Windermere syndromeLambert-Eaton syndrome (LEMS)Lamivudine (3TC)LamotrigineLangerhans Cell Histiocytosis XLansoprazoleLanthanumLateral Medullary SyndromeLaxativesLe Fort FracturesLead toxicityLeber hereditary optic neuropathy (LHON)LeflunomideLegal definition of BlindnessLegionella pneumophilaLeishmaniasis (Cutaenous and Visceral)Lemierre's syndromeLenalidomide (Revlimid)Length Dependent PolyneuropathyLennox-Gastaut syndromeLenticulostriate branch occlusionLeprosyLeptinLeptospira interrogansLeptospirosis (Weil's Disease) (Notifiable)Leriche syndrome (aortoiliac occlusive disease)Lesch-Nyhan syndrome (Children)LeukaemiaLeukaemias in GeneralLeukoariosisLeukocytoclastic vasculitisLeukotrienesLevetiracetam (Keppra)LevodopaLevomepromazineLevosimendanLi Fraumeni syndromeLichen PlanusLiddle's syndromeLidocaine(Lignocaine)Lightning strikeLimb girdle dystrophyLimbic EncephalitisLinagliptin (Trajenta)LinezolidLinkageLiothyronine Sodium L-Triodothyronine (T3)Lipid emulsion therapy - 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small intestineMalaria (non falciparum)Malaria FalciparumMale InfertilityMale Urethral CatheterisationMale erectile dysfunctionMalignant AscitesMalignant Hyperpyrexia (Malignant Hyperthermia)Malignant HypertensionMalignant MelanomaMalignant pleural mesotheliomaMallet FingerMallory-Weiss TearMalnutrition Universal Screening ToolManiaMannitolMantle cell lymphomaMarantic EndocarditisMarasmusMaraviroc (Celsentri)Marfan syndromeMarginal Zone LymphomaMassive HaemoptysisMaturity Onset Diabetes of the Young (MODY)McArdles disease (type V)Measles (notifiable)MebeverineMeckel's diverticulumMeconiumMedian NerveMedical Mnemonics Basic SciencesMedical Mnemonics CardiologyMedical Mnemonics EndocrineMedical Mnemonics Mental HealthMedical Mnemonics MiscellaneousMedical Mnemonics NeurologyMedical ProceduresMedical TeethMedullary Sponge kidneyMedulloblastomaMefenamic acidMefloquine (Larium)Megaloblastic anaemiaMelatoninMelioidosisMemantine HydrochlorideMembranous GlomerulonephritisMenetrier diseaseMeniere diseaseMeningiomaMeningitis in the ImmunocompromisedMenopauseMenstrual cycleMental Capacity Act 2005Mental Health Act 1983Mental State ExaminationMercaptopurineMeropenemMesalazine (Aminosalicylate)Mesangiocapillary GlomerulonephritisMesenteric infarctionMetabolic Syndrome XMetabolic acidosisMetabolic alkalosisMetachromic leucodystrophyMetastatic AdenocarcinomaMetastatic bone diseaseMetforminMethaemoglobinaemiaMethanol ToxicityMethodoneMethods to reduce toxin absorptionMethotrexateMethylcelluloseMethylprednisoloneMetoclopramideMetolazoneMetoprololMetronidazole (Flagyl)Metyrapone (Metopirone)MiconazoleMicroangiopathic Haemolytic anaemiaMicrocytic anaemiaMicroscopic PolyangiitisMicroscopic colitisMicrostomiaMidazolamMiddle East Resp Syndrome (MERS) CoronavirusMidodrineMigraine Disability Assessment (MIDAS)Miller-Fisher syndromeMilwaukee shoulder syndromeMini Mental State Examination (MMSE)Minimal Change Disease GlomerulonephritisMinocyclineMinoxidilMirabegronMirizzi syndromeMirtazapineMiscarriageMisoprostolMitochondrial diseasesMitral Regurgitation (Incompetence)Mitral StenosisMitral Stenosis vs Regurgitation - DominanceMitral Valve prolapseMittleschmerzMixed Connective Tissue Disease (MCTD)Mobility aidsModified Duke Criteria for EndocarditisModified Oxford Handicap Scale (MOHS)Modified Rankin ScoreMolluscum contagiosumMonoclonal gammopathy of undetermined significanceMonocular loss of visionMonocytesMonosodium glutamate (MSG) syndromeMontelukastMontreal Cognitive Assessment (MOCA)Moraxella catarrhalisMorphine SulphateMosquito borne diseasesMotor Neuron Disease (MND-ALS)Moyamoya diseaseMucormycosisMultifocal Atrial TachycardiaMultifocal Motor Neuropathy with Conduction blockMultiple Antithrombotics AnticoagulantsMultiple Endocrine Neoplasia type 1 (MEN1)Multiple Endocrine Neoplasia type II (MEN2)Multiple MyelomaMultiple PregnancyMultiple Sclerosis (MS) DemyelinationMultiple System Atrophy (MSA)Mumps (Notifiable)Muscles of the Abdominal RegionMuscles of the BackMuscles of the Head and NeckMuscles of the Lower LimbMuscles of the Pelvis and PerineumMuscles of the Thoracic RegionMuscles of the Upper limbMyasthenia GravisMycobacterium TuberculosisMycophenolate mofetilMycoplasma pneumoniaeMycoplasmasMycosis Fungoides (Sezary Syndrome)Myelodysplastic syndrome (Myelodysplasia)MyelofibrosisMyelofibrosis vs CMLMyelopathyMyeloproliferative disordersMyobacterium avium Complex InfectionMyocardial perfusionMyoclonusMyotonic dystrophy - Dystropica myotonicaMyxoedema comaN-Acetylcysteine (Parvolex)NEWS Reacting to Low Oxygen SaturationsNICE Guidelines LinksNICE Trauma Guidance Summary 2016NSAID toxicityNaloxone (Narcan) Opiate antagonistNaproxenNarcolepsyNasal polypsNasogastric tube insertionNatalizumab (Tysabri)National Early Warning Score NEWS 2 ScoreNeck PainNeck swellings and lumpsNecrotising Enterocolitis (Infants)Necrotising fasciitisNeedlestick injuryNefopamNeisseria gonorrhoeaeNeisseria meningitidisNelson SyndromeNeomycinNeonatal Abstinence Syndrome NASNeonatal JaundiceNeonatal Lupus ErythematosusNeonatal meningitisNeostigmineNephritic syndromeNephroblastoma (Wilm's tumour)Nephrotic syndromeNephrotoxic drugsNerve conduction studiesNerve fibresNeuroanatomy 101Neuroanatomy imagesNeuroblastomaNeurocysticercosisNeuroferrinopathyNeurofibromatosis Type 1Neurofibromatosis Type 2Neuroleptic Malignant SyndromeNeurological - Relative Afferent pupillary defectNeurological - Vision and Eye movementsNeurological Examination - 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IdarucizumabPraziquantelPrazosinPre-Operative AssessmentPreEclampsia, Eclapsmia and HELLPPrednisolonePrednisonePregabalinPremature LabourPremature MenopausePresbyacusisPrescribing InformationPrescribing in PregnancyPressure soresPrevotella (Bacteroides) melaninogenicaPriapismPrimaquinePrimary (Chronic simple) Open angle GlaucomaPrimary Biliary CirrhosisPrimary CNS LymphomaPrimary HyperparathyroidismPrimary Sclerosing CholangitisPrimary ciliary dyskinesiaPrimary hyperaldosteronism (Conn's syndrome)Primary progressive aphasia (Dementia)ProbenicidProchlorperazine (Stemetil)ProcyclidineProgressive Multifocal Leukoencephalopathy (PML)Progressive Supranuclear Palsy (PSP)ProlactinomaPropafenonePropanthelinePropionibacteriumPropofolPropranololPropylthiouracilProstate cancerProsthetic ValvesProtamine SulfateProtein C DeficiencyProtein S DeficiencyProtein losing enteropathyProtein p53Protein synthesisProteusProthrombin 20210A mutationProthrombin Complex Concentrates (PCC)Prothrombin time and CoagulationProthrombotic disordersProton Pump InhibitorsProximal myopathyPrucalopridePsammoma bodiesPseudohypoparathyroidismPseudomonas infection (Pseudomonas aeruginosa)Psoas AbscessPsoriasisPsoriatic arthritisPsychogenic PolydipsiaPubic Lice (Pediculosis Pubis)Pulmonary Alveolar ProteinosisPulmonary Arteriovenous malformationPulmonary EmbolismPulmonary Eosinophilia and CXR changesPulmonary HypertensionPulmonary Hypertension - 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Age over 65SimvastatinSinus BradycardiaSinus Node diseaseSinus TachycardiaSitagliptinSitosterolemiaSjogren's syndromeSkin and soft tissue infectionsSkull AnatomySleep physiologySlipped Upper Femoral Epiphysis (SUFE)Small Bowel IschaemiaSmall Bowel ObstructionSmall vessel diseaseSmallpoxSmokingSnake BitesSneddon SyndromeSodium BicarbonateSodium NitroprussideSodium PhysiologySodium PicosulfateSodium Thiopental - Sodium ThiopentoneSodium Valproate (Epilim Depakote)Sodium Zirconium Cyclosilicate (Lokelma)Soft tissue injuries (sprains, strains)SolifenacinSolitary Pulmonary NoduleSotalol HydrochlorideSpetzler-Martin Grading of AVMSpina BifidaSpinal Cord AnatomySpinal Cord Arteriovenous MalformationsSpinal Cord CompressionSpinal Cord HaematomaSpinal Cord InfarctionSpinal StenosisSpirometrySpironolactoneSpleenSplenic RuptureSpondylolisthesisSpontaneous Bacterial PeritonitisSpontaneous intracranial hypotensionSquamous Cell CarcinomaSt John's WortStaphylococcal InfectionsStaphylococcus aureusStaphylococcus epidermidisStaphylococcus saprophyticusStatinStatus Epilepticus (Epilepsy)Stavudine (Zerit) d4TStevens-Johnson SyndromeStiff Person SyndromeStrabismus (Lazy Eye)Streptobacillus moniliformisStreptococci - anaerobesStreptococcusStreptococcus agalactiaeStreptococcus milleriStreptococcus pneumoniae (Pneumococcus)Streptococcus pyogenesStreptococcus viridansStreptokinaseStreptomycinStridorStroke - Arterial Occlusion and clinical correlateStroke - Epidemiology and risk factorsStroke - General ManagementStroke - ImagingStroke ASPECTS scoringStroke CollateralsStroke Risk FactorsStroke ThrombolysisStrongyloides stercoralis (threadworm)StrontiumSubacute Sclerosing PanencephalitisSubacute ThyroiditisSubarachnoid HaemorrhageSubclavian Steal SyndromeSubclavian vein thrombosisSubdural haematomaSucralfateSudden Cardiac Death (SCD)Sudden Infant Death Syndrome (SIDS)Sudden sensorineural hearing loss (SNHL)SuicideSulfasalazine - SulphasalazineSulphonamide (Sulphamethoxazole)SumatriptanSuperior Mesenteric Artery (SMA) SyndromeSuperior Sagittal Sinus ThrombosisSuperior vena caval obstruction syndromeSupracondylar Femur FracturesSupracondylar Humerus FracturesSupraspinatus tendonitisSupraventricular TachycardiaSurgical CricothyroidotomySurgical prophylaxisSurgical site infectionSusac syndromeSuxamethoniumSydenham's choreaSynchronised DC CardioversionSyncopeSyndrome X (Cardiology)Syndrome of Inappropriate ADH (SIADH) secretionSyndromes with Severe Cognitive IssuesSyphilisSyringobulbiaSyringomyeliaSystemic AmyloidosisSystemic Lupus Erythematosus (SLE)Systemic MastocytosisSystemic SclerosisT cellsTIMI scoreTMN Staging tumoursTNF receptor-associated periodic syndromeTORCH infectionsTURP Hyponatraemia syndromeTabes dorsalisTacrolimusTafamidisTakayasu arteritis (pulseless disease)Takotsubo CardiomyopathyTamoxifenTamsulosin (Flomax)Tanner Stages of Pubertal DevelopmentTardive DyskinesiasTay-Sachs diseaseTazocin (Tazobactam - Piperacillin)TeicoplaninTelomeresTemazepamTemozolomide (Temodal)Template XTemplate two columns listTemporal (Giant Cell GCA) ArteritisTenecteplaseTennis ElbowTensilon testTension PneumothoraxTerbutalineTeriparatideTerlipressinTertiary hyperparathyroidismTesticular CancerTesticular torsionTestingTetrabenazineTetracosactide (Synacthen)TetracyclinesTetralogy of Fallot (Children)Thalamic HaemorrhageThalamic Pain SyndromeThalamic Stroke SyndromeThalidomideTheophyllineTheophylline toxicityThiamineThird Degree (complete) Heart BlockThoracic TraumaThoracic anatomyThoracic outlet syndromeThrombocytosisThrombolysisThrombophilia testingThrombotic Thrombocytopenic purpura (TTP)Thyroglossal Cyst (Children)Thyroid CancerThyroid Function Tests and antbodiesThyroid GlandThyroid Storm - Thyrotoxic crisisThyroid Surgery (Thyroidectomy)Thyroid noduleThyrotoxicosis and HyperthyroidismTiagabineTibia and Fibula fractures and InjuriesTicagrelorTick ParalysisTimololTinea capitisTinidazoleTinzaparin (Innohep)Tiotropium (Spiriva)Titre - 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Paratyphoid fever (Enteric Fever)Tyrosine Kinase receptorsUS vs UK Drug namesUbiquitinUlcerative ColitisUlnar nerveUltrasound - Echo basicsUndifferentiated Inflammatory Arthritis (Children)Unexplained symptomsUpper Gastrointestinal Bleed (GI Bleed)Upper-Lower Motor Neurone signsUrea and ElectrolytesUrethral syndomeUrinary CatheterisationUrinary Incontinence (Stress and Urge)Urinary Tract Infection (UTI Children)Urinary Tract InfectionsUrinary Tract ObstructionUrinary UTI Antibiotic guidanceUrine AnalysisUrothelial tumoursUrticariaUterusVIPomasVTE DVT PE in PregnancyVaginal CarcinomaValaciclovirValsartanVancomycinVariable rate intravenous insulin infusion VRIIIVariant (Prinzmetal) AnginaVaricella-Zoster (Chickenpox Shingles) InfectionVariegate PorphyriaVascular DementiaVasculitis - General Issues and ClassificationVasopressin (AVP) Antidiuretic hormoneVasovagal syncopeVaughan-Williams ClassificationVecuroniumVedolizumab (Entyvio)VenlafaxineVenous Insufficiency and Leg UlcersVenous access Venflons and Central linesVentilator associated pneumonia (VAP)Ventricular FibrillationVentricular Septal defect (VSD) (Children)Ventricular TachycardiaVentricular ectopic beatsVerapamilVertebral artery dissectionVertigoVesicoureteric reflux (VUR) (Children)Vibrio parahaemolyticusVibrio vulnificusVibrio vulnificus Vigabatrin (Sabril)VinblastineVincristineViral MeningitisViral associated cancersVirusesVisual acuityVitamin A deficiency (Children)Vitamin B1 Thiamine deficiencyVitamin B12 deficiencyVitamin B12 excessVitamin C deficiency (Scurvy)Vitamin D (1,25 OH2)Vitamin D (25 OH D)Vitamin D deficiencyVitamin D resistant rickets (Children)Vitamin K (Phytomenadione)Vitamin K deficiencyVitiligoVoltarol (Diclofenac)Von Gierke Disease (Children)Von Hippel LindauVon Willebrand DiseaseWaardenburg's syndrome (Children)Wagner Classification Diabetic foot ulcersWaldenstrom Macroglobulinaemia (WM)Wallerian DegenerationWarfarinWarfarin and BleedingWater PhysiologyWatershed InfarctsWerdnig Hoffman Disease (Children)Wernicke Korsakoff SyndromeWhite Blood Cells - LeukocytesWilliams Syndrome (Children)Wilson diseaseWiskott-Aldrich syndrome (Children)Wolff-Parkinson White syndrome (WPW)Wolfram syndrome (DIDMOAD)Wound healingX linked Agammaglobulinaemia (Bruton)X linked Hypophosphataemic ricketsX-linked IchthyosisX-linked lymphoproliferative disease (Children)Xeroderma pigmentosumYellow FeverYellow Nail SyndromeYersinia enterocoliticaYersinia pestis - Bubonic PlagueYersinia pseudotuberculosisZZAAAZZ_Abnormal charZabramski Classification of CavernomasZidovudine (Retrovir) AZT - ZDVZieve's syndromeZika virusZinc deficiencyZoledronic acidZollinger Ellison syndromeZolpidemZopicloneeGFR

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Brain Physiology


Basics
  • The brain contains 1011 neurons and perhaps 10-50 times as many glial cells. About 40% of human genes are involved in some part with its development and structure. The excitability of neurons is key to how they work. The structure of individual neurons also varies depending on the individual role they play. A neuron is composed of a cell body (soma) + multiple dendrites + a single axon
  • A typical neuron has a large cell body. Input is via multiple dendrites and output is via an axon which can be a metre in length. There are multiple types of neuron all specialised for their particular role.
  • Different Neurons have lots of sub-specialisation in terms of structure and function. The neurons are the fundamental building block of the CNS though only form 10% of the cells within the CNS. Their electrical excitable properties and ability to conduct nerve impulse mean that the neurones can transmit or even process information rather like a computer. Several neurons with different inputs can have this information pass on to one neurone which can either depolarise, hyperpolarise or have no effect at all depending on the state before the stimulus and the stimulus. The neurone is composed of a cell body or "soma" which contains mitochondria, Golgi apparatus and peroxisomes. Endoplasmic reticulum stains and is known as Nissl substance.
  • Body: Contains Nissl substance - which is a collection of polyribosome and rough endoplasmic reticulum as well as neurofilaments and microtubules which for part of the cytoskeleton which continues into the Dendron and axonal processes.
  • Dendrites: Typically long and thinly covered by dendritic spines. Multiple input points usually of high resistance preventing unwanted stimulation from background electrical activity. Attached to the cell body.
  • Axon: Usually single and starts at the area called the axon hillock close to the cell body with a high concentration of sodium channels which forms a sort of trigger zone allowing the initiation of an action potential to travel along the axon.
Introduction
  • The Resting membrane potential of a neuron is at -70 mV. The cell begins to depolarize at -55mV and when depolarized this rises to +40 mV. At times the cell is hyperpolarized when the membrane potential is less than -70mV. The intracellular concentration of potassium is high. It is the equilibrium potential of potassium (-90mV)? the point at which there is the equilibrium of potassium concentration across the cell membrane that resembles closest the actual value. The conductance through potassium channels at rest is much greater than through sodium channels. There is obviously movement of potassium out of the cell along its concentration gradient but this leaves a net negative electrical gradient within the cell. The effect of Na+, Cl- and Ca++ ions have relatively little effect. With an action potential, there is a transient increase in Na permeability and this leads to Na movement into the cell and the inside of the cell becomes more positive which acts to cause even greater Na permeability with a positive feedback loop that rapidly increases the membrane potential. There follows a transient rise in potassium permeability such that it flows out of the cell making the inside more negative even more so than at rest. The ions pass through voltage-gated ion channels. During an action potential, the charge inside the cell can become even more negative and this is called hyperpolarisation often due to further movement out of potassium ions which can render the cells refractory for a short period. The Nernst equation can be used to calculate resting membrane potentials. Interestingly different cells in the body have similar but not always identical resting membrane potentials e.g. neurons -70 mV, glial cells -90mV skeletal muscle cells? 80mV and smooth muscle cells -70 mV. Membrane potential State + 40 mV Depolarised -70 mV Resting -90 mV Hyperpolarised E K = - 90 mV E Na = + 60 mV Resting MP = - 70 mV
Summation
    Imagine a neuron cell body with its dendrites abutted by the synaptic boutons of the distal end of other axons. The generation of an action potential is dependent on the input to the neuron in question. The axons may provide excitatory inputs raising the local membrane potential of the neuron or inhibitory reducing the cell membrane potential. The following may occur " Partial depolarization due to one or more depolarising or hyperpolarizing inputs which do not raise the membrane potential to a level at which depolarization occurs " Temporal excitatory summation - a series of impulses from one excitatory fibre over a period of time produces a membrane potential high enough to result in depolarisation " Spatial excitatory summation occurs when impulses in at least two excitatory fibres cause two synaptic depolarisations which trigger an action potential " Spatial excitatory summation with inhibition - impulses from at least two excitatory neurons fail to depolarize the cell due to inhibition from an inhibitory neuron " Spatial excitatory summation with inhibition - impulses from at least two excitatory neurons depolarize the cell despite inhibition from an inhibitory neuron When several stimuli arrive quickly one after another from the same fibre is called temporal summation. Spatial summation occurs when two or more stimuli arrive at a neuron but at different locations usually separated by micrometres. If the sum of the potentials reaches a certain point then an action potential is generated by the sudden opening of fast Na+ voltage-gated channels. Voltage-gated means that they open in response to changing membrane potential. The channels usually open when the membrane potential reaches - 55mV. An understanding of this is required in the understanding of neurological physiological and pathological processes from epilepsy to migraine. An increase in Na+ conductance and so influx making the inner cell more positive is excitatory whereas an increase in K+ conductance and so outflow is inhibitory as is increase Cl- conductance which flows in.

Neuronal transmission
    Myelin is produced in the CNS by the oligodendrocytes which are derived from glioblasts. In the peripheral nervous system, myelination is by Schwann cells and these can only myelinate one axon whereas in the CNS oligodendrocytes can form myelin sheaths around multiple axons. There are gaps between adjacent myelinated areas called nodes of Ranvier where the action potential depolarization happens. Here in the CNS an astrocyte foot process also abuts.

    A cell depolarizing will lead to adjacent cells depolarizing. The nodes of Ranvier are close enough to the next node so that a wave of depolarisation can pass quickly along the axon, to a quicker extent than were the cell to be unmyelinated. This is called "salutatory" conduction as the transmission jumps from node to node.

    There are many diseases in the CNS and the PNS which are associated with demyelination possibly as myelin is composed of proteins that are strongly antigenic, With chronic stroke disease, there is often "white matter disease" due to ischaemia due to disease of the small penetrating arteries.

Synapses
    A synapse is a point of contact between two neurons. They can be either electrical or chemical. Electrical ones are uncommon and are really there to allow a simultaneously continuous passage of an action potential. There is cytoplasmic continuity through 1.5 nm channels. Modulation is not possible as all cells are depolarized together. Seen in the respiratory centre of the brain such that they produce a sustained continuous discharge during inspiration or involved in the movement of the eyes - saccades. Chemical synapses lead to the release of a transmitter which may depolarise or hyperpolarise the postsynaptic membrane. Depolarisation is excitatory and hyperpolarisation is an inhibitory effect.

Chemical Synapse
    The synaptic terminal allows the conversion of an action potential into a chemical response. At the distal end of the axon lies the presynaptic terminal separated from the postsynaptic membrane of usually a dendrite by a synaptic cleft which is about 20 nm across. The presynaptic terminal contains numerous vesicles of neurotransmitters that have been brought there by axonal transport. There is a degree of variability and the pos synaptic membrane may be to a dendrite, the body of a neuron or even another axon. A spreading wave of depolarization reaches and depolarizes the presynaptic terminal and causes the influx of calcium ions through voltage-gated calcium channels. These enter the cell and trigger secondary effects such as neurotransmitter release such as Acetylcholine, glutamate, GABA and others. This then crosses the synaptic cleft and may lead to changes in postsynaptic cells with the formation of an EPSP or IPSPs.

    Neurotransmitters such as GABA allow Cl- ions to enter cells which make the internal more negative "hyperpolarises" them so making them less likely to depolarize and is so inhibitory. Other such as glutamate is excitatory and causes depolarization. These can generate an Excitatory postsynaptic potential (EPSP). Only at a certain strength with the EPSP generate a postsynaptic action potential. This depends on the number of activated ligand-gated channels.

Brain Metabolism
    About 90% of normal brain metabolism required to maintain ion gradients and transmit electrical impulses comes from the oxidative breakdown of glucose. Other molecules such as ketone bodies may be metabolized in severe starvation. Other molecules such as lactate can also be metabolized. Neuronal cells have a very high metabolic rate and glycogen storage is poor. Anaerobic metabolism is not possible to any real extent. Glucose and oxygen supply must be continuous to match the high metabolic rate. Unlike other tissues glucose entry to cells is not dependent on Insulin. In patients with no Insulin, glucose can still enter neurons. However systemic hypoglycaemia will cause neuroglycopenia with marked symptoms and neuronal cell dysfunction. Prolonged hypoglycaemia will cause neuronal damage. Glutamate is taken up by ?? glial cells neurons which take up ammonia and is released as glutamine. This helps keep the brain free of ammonia which is very toxic to neuronal function. The cerebral cortex, basal ganglia and thalamus and inferior colliculus all have a high oxygen demand. Hypoxia for instance can lead to symptoms of Parkinsonism.

Internal Structure
  • The axon is surrounded by an axolemmal membrane. The cytoskeleton composed of microfilaments and microtubules allows transport. Axonal transport within the cell can be from the cell body to the synapse (anterograde) or from the synapse to the cell body (retrograde). Microtubules can provide fast axonal transplant whereby molecules are actively transported by specific motor molecules. The proteins kinesin is involved in anterograde transport and cytoplasmic dynein is involved in retrograde transport.
  • The outside of the axon is myelinated with a 1 um gap (node of Ranvier) every 1 mm. This helps increase the speed of salutatory conduction of action potential along the axon. Damage to myelin occurs in MS, ADEM and PML. Each axon has a few small branches terminated with a synaptic ending or bouton. Direction of information flow dendrites (many) Cell body Axon (single)
Axonal transport
  • A typical neuron is composed of up to 7 dendrites which are branching structures that extend out from the neuronal cell body and largely receive input. Some dendrites particularly in the cortex have small projections called dendritic spines. The cell body also has a thickened area called an axon hillock and then a long extension forming an axon. The terminal end of the axon forms synaptic knobs often storing neurotransmitters in vesicular structures. The axons are often enveloped in myelin a protein-lipid complex which within the CNS is produced by an oligodendrocyte.
  • Information appears to travel from dendrites to axons. Axons are low in ribosomes and most synthetic function occurs in the cell body and is transported along the axon by the axoplasmic flow. Flow into axons or dendrites is both anterograde which is mediated by kinesin. The speed of anterograde transport can be up to 40 cm/day. This is for transporting vesicles and neurotransmitter precursors and receptor proteins. There is also slow anterograde transport for structural elements at 1 cm/day.
  • Retrograde transport is mediated by cytoplasmic dynein can also be quite fast at 12-20 cm/day. Failure of dynein is possibly linked to motor neurone disease. Both occur actively along microtubules. ATP is used for transport and neurons are rich in mitochondria. Microtubule binding proteins include ATPases. Viruses such as rabies and tetanus toxin can be carried centrally by the retrograde axoplasmic flow.
Cortical structure
  • The cerebral cortex is made up of a 5mm layer of grey cells above a dense thick inner layer of white matter. The overall surface area is increased by the folds of sulci and gyri. The cortex can be seen to be composed of six layers of cells that vary in size and structure.
  • Back in 1909 Brodmann produced a map of the cerebral cortex based on the microarchitecture of the cells and staining for Nissl substance which separates neurons from glial cells. This was before we had an understanding of many of the functions of these areas and the system has stood the test of time. Other improvements have been developed by others. It is quite clear that anatomy is related to function.
  • Cells in the cortex are arranged in a columnar structure and can this can be seen with microelectrode stimulation. Areas with similar function lie close together. For example Broca's area lies within the inferior region of the precentral motor cortex near to those areas that control voluntary movement of the lips, tongue, larynx and pharynx. Broca's produces the content of speech content and damage here leads to expressive dysphasia.
  • A lesion in the inferior area of the precentral motor cortex leads to dysarthria and facial weakness. Indeed Broca's discovery of dysphasia in a patient whose subsequent post mortem revealed a lesion due to syphilis in the area that became known as Broca's area was one of the key findings to suggest localization of function within the brain.

Astrocytes
  • Astrocytes are the largest and commonest of glial cells. They are star-like shaped with multiple long processes that can make them resemble neurons. The cytoplasm is abundant with intermediate filaments which give the cells some rigidity helping to support the brain structure. Glycogen granules acting as a glucose store are found.
  • Astrocytes stain for glial fibrillary acidic protein which is cell-specific. Unlike neurons, they are able to multiply and can form scar tissue when there is localised injury(gliosis). Astrocytes have foot processes that abut onto capillaries or pia mater forming a glial membrane. They have multiple functions indicated in the table on the right
Glial (from the greek for glue) cells
  • It has been estimated to outnumber neurons by a factor of over 10 to 1. They are not involved with information processing (as far as we can tell) but perform general housekeeping and other functions in the CNS as will be discussed later.
  • They also hold the structures of the CNS together. Neurons are packed within the CNS at about 80,000 per mm2 of cortex and this is uniform across most of the cortex. The exception is the high density of 200,000 per mm2 in the primary visual cortex. Astrocytes can resemble neurons in having long processes which resemble dendrites.
  • However astrocytes do not contain Nissl bodies (densely packed rough endoplasmic reticulum seen in neuron cell bodies). Astrocytes do however stain for glial fibrillary acidic protein which is cell specific. Microglia are derived from the bone marrow and are cells of the immune system. They have several functions including acting as macrophages phagocytosing debris.

Basal Ganglia
  • The basal ganglia is a collection of interconnected nuclei (neuronal cell bodies) lying deep below the cortex. It is composed of the following structures. The putamen (laterally) and globus pallidus (medially) form the lenticular or lentiform nucleus (lens-shaped).
  • The caudate and putamen are also called the neostriatum. Grey matter strands cross the internal capsule to connect these structures and so gives the area the name of the corpus striatum. The putamen is the larger ovoid mass that lies laterally with its lateral side separated vary slightly from the insular cortex and the external capsule and claustrum.
  • Medially attached to the Globus Pallidus. The Globus Pallidus is a smaller triangular-shaped structure and lies medially with its medial relation being the internal capsule. The globus pallidus is a major source of output from the basal ganglia. It is divided by a lamina into Globus pallidus externa and interna.
  • The caudate nucleus is a large mass of grey cells making up a head, body and tail. Anteriorly seen on scans at the lateral border of the anterior horn of the lateral ventricle. It lies then on the lateral wall of the ventricle and there is a tail that passes to form the roof of the inferior temporal horn of the ventricle. The internal capsule separates it from the putamen. The caudate is notable as being diminished in size in Huntington's chorea.
  • The caudate and putamen receive stimulatory input from the cerebral cortex mediated (Glutamate) and from the substantia nigra (Dopamine). The caudate/putamen gives an inhibitory output (GABA) to the Globus pallidus and substantia nigra. The Globus pallidus and Substantia nigra also send inhibitory signals to the ventral thalamic nucleus of the thalamus (GABA) which in turn feeds to the cortex (glutamate).
  • The Basal ganglia are concerned with movements of the contralateral limbs and it would seem that it stimulates and inhibits various regions thus modulating motor output. All of these structures are prone to lacunar infarcts and deep haemorrhage
Brain Stem Anatomy/ Cranial nerves

The Brainstem contains all the cranial nerves other than Olfactory and optic nerves

NerveLevel
I. Olfactory Above Brainstem
II. Optic Above Brainstem synapses with lateral geniculate ganglion of the thalamus
III. Oculomotor Midbrain. Oculomotor (IIIrd) nucleus at level of the superior colliculus. Cranial nerve III innervates all the extraocular muscles except for the lateral rectus and superior oblique. In innervates the medial rectus, superior rectus, inferior rectus, and inferior oblique muscles. It exits the brain stem anterior-medially from the midbrain between the posterior cerebral artery and the superior cerebellar artery. It can be affected by aneurysms of these arteries.
IV. Trochlear Midbrain. Trochlear nerve (IV): nucleus at level of lower colliculus. Exits brainstem posteriorly, Innervates the superior oblique muscle. It travels posteriorly and medially, crosses the midline, wraps around the midbrain, and exits the brain stem laterally between the posterior cerebral artery and superior cerebellar artery. Long intracranial course. Travels through the cavernous sinus and enters the orbit through the superior orbital fissure. Because it crosses the midline, the right trochlear nerve innervates the left superior oblique muscle. If the left superior oblique muscle is weak, then tilting the head to the right reduces the diplopia, and tilting the head to the left would worsen the diplopia. So a patient tilts his or her head away from the affected eye
V. Trigeminal Pons. Large trunk exits anteriorly as trigeminal ganglion and splits into Ophthalmic, Maxillary and Mandibular branches. Its fibres contain elements from 4 different nuclei
  • Mesencephalic nucleus (which is a nucleus of unipolar cell bodies similar to the dorsal root ganglion, with no synapse)
  • Chief sensory nucleus
  • Descending spinal nucleus
  • Motor nucleus: muscles of mastication
  • VI. Abducent Pons. The abducens(t) nerve, abducts the eye.
    VII Facial Pons. Muscles of facial expression (special visceral efferent): The innervation can be separated into the muscles of the upper part of the face and the muscles of the lower part of the face. The supranuclear input responsible for the movement of the upper facial musculature is a bilateral input from the cortex to the nucleus. The supranuclear input responsible for the movement of the lower facial musculature is only a contralateral input from the cortex to the facial nucleus
  • Innervates the lacrimal, submandibular, sublingual, and parotid glands (general visceral efferent)
  • supplies taste sensation to the anterior two-thirds of the tongue (special visceral afferent)
  • supplies sensation to the external ear (general somatic afferent).
  • VIII. Auditory Pons
    IX. Glossopharyngeal Medulla
    X. Vagus Medulla
    XI. Spinal accessory Medulla
    XII. Hypoglossal Medulla
    Midbrain
    • Oculomotor (IIIrd) nucleus: SEE ABOVE
    • Edinger-Westphal nucleus: Lies in the posterior midbrain. It supplies parasympathetic fibres that terminate in the ciliary ganglion via cranial nerve III. It is mainly involved in pupillary constriction and the light accommodation reflex.
    • Substantia Nigra (SN): The primary efferent neurotransmitter from the substantia nigra is dopamine. Parkinson disease damages the substantia nigra. Pathologically, the neurons lose their melanin and the nucleus becomes depigmented. Many neurons also contain inclusion bodies called Lewy bodies.
    • Red nucleus (RN): mass located in the ventral portion of the tegmentum of the midbrain. It is a relay centre for many of the efferent cerebellar tracts. The crossed fibres of the superior cerebellar peduncle (SCP) pass through and around its edges.
    • Edinger-Westphal nucleus: lies in the posterior midbrain, supplies parasympathetic fibres that terminate in the ciliary ganglion via cranial nerve III. It is mainly involved in pupillary constriction and the light accommodation reflex.
    Pons
    • Vestibulocochlear nerve (VIII): 2 distinct sensory divisions:
    • Vestibular nerve : responds to position and movement of the head, serving functions often identified as equilibrium.
    • Cochlear (or auditory) nerve : cochlear nerve mediates auditory functions.
    Medulla
    • Nucleus ambiguus: nucleus that lies in the depths of the medulla. It innervates the volitional muscles of the pharynx by way of both cranial nerves IX and X and the larynx (for phonation) via cranial nerve X. The larynx and pharynx have bilateral cortical input.
    • Nucleus solitarius: nucleus in the medulla that receives afferent information from the larynx (via cranial nerve X) and posterior pharynx and mediates the gag and cough reflexes (cranial nerves IX and X). Pain sensation from these areas enters the brain stem through cranial nerves IX and X but terminates in the descending spinal tract of the trigeminal nerve.
    • Salivatory nucleus: Superior salivatory nucleus sends efferent autonomic fibers (general visceral efferent) through cranial nerve VII to innervate the lacrimal, submandibular, and sublingual glands as well as the mucous membranes of the nose and hard and soft palate. The inferior salivatory nucleus sends efferent autonomic fibers via cranial nerve IX to innervate the parotid gland.
    • Gustatory nucleus : nucleus in the medulla that receives afferent sensory information for the sensation of taste. Taste from the anterior two-thirds of the tongue is innervated by the chorda tympani (cranial nerve VII), the posterior one-third of the tongue is innervated by cranial nerve IX, and the epiglottis is innervated by cranial nerve X.