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198 articles

Emergency MedicineABCDE ApproachThe ABCDE approach is a structured method for the immediate assessment and treatment of a deteriorating or critically ill patient: Airway, Breathing, Circulation, Disability, Exposure. The central rule is treat life-t…22 min read
Vascular MedicineAbdominal Aortic Aneurysm in AdultsAbdominal aortic aneurysm (AAA) is permanent dilation of the abdominal aorta, conventionally defined as a maximum infrarenal diameter ≥3.0 cm. Most AAAs are asymptomatic and are detected by screening or incidental ima…13 min read
Emergency MedicineAcetaminophen PoisoningAcetaminophen is usually safe at therapeutic doses but can cause dose-dependent centrilobular hepatic necrosis after overdose. Toxicity occurs when normal glucuronidation and sulfation pathways become saturated and mo…26 min read
EndocrinologyAcromegaly in AdultsAcromegaly is chronic growth hormone (GH) excess, almost always from a GH-secreting pituitary neuroendocrine tumor, causing elevated insulin-like growth factor 1 (IGF-1), progressive somatic overgrowth, cardiometaboli…11 min read
OphthalmologyAcute Angle-Closure GlaucomaAcute angle-closure crisis is sudden symptomatic closure of the anterior chamber angle with a rapid rise in intraocular pressure (IOP). The typical presentation is severe unilateral ocular or periocular pain, red eye,…13 min read
CardiologyAcute Aortic SyndromeAcute aortic syndrome (AAS) is a time-critical spectrum of aortic wall failure that includes acute aortic dissection, intramural hematoma (IMH), and penetrating atherosclerotic ulcer (PAU). These entities can overlap…19 min read
SurgeryAcute AppendicitisAcute appendicitis is inflammation of the vermiform appendix and a common cause of urgent abdominal surgery. Diagnosis is based on clinical probability plus selective imaging rather than any single symptom, laboratory…12 min read
PulmonologyAcute Asthma ExacerbationAn asthma exacerbation is an acute or subacute worsening of dyspnea, wheeze, cough or chest tightness with a fall in expiratory airflow compared with the patient’s usual state. The attack is caused by variable airflow…23 min read
Infectious DiseaseAcute Bacterial MeningitisAcute bacterial meningitis is infection-driven inflammation of the leptomeninges and cerebrospinal fluid (CSF). It can progress over hours to sepsis, shock, cerebral edema, seizures, raised intracranial pressure, hern…19 min read
UrologyAcute Bacterial ProstatitisAcute bacterial prostatitis (ABP) is an acute bacterial infection of the prostate that typically causes fever or systemic illness together with pelvic/perineal pain and lower urinary tract symptoms. Enteric Gram-negat…12 min read
OtolaryngologyAcute Bacterial Rhinosinusitis in AdultsAcute bacterial rhinosinusitis (ABRS) is a clinical syndrome of acute sinonasal inflammation in which bacterial infection is likely enough to change management. Most acute rhinosinusitis follows a viral upper respirat…9 min read
PediatricsAcute BronchiolitisAcute bronchiolitis is a clinical syndrome of viral lower respiratory tract infection in infants and young children, most often during the first year of life. A typical illness begins with coryza and cough, then progr…16 min read
GastroenterologyAcute CholangitisAcute cholangitis is bacterial infection of an obstructed biliary system. The combination of biliary obstruction, rising intraductal pressure, and bacterial contamination can rapidly cause bacteremia, sepsis, and mult…18 min read
SurgeryAcute CholecystitisAcute cholecystitis is acute gallbladder inflammation, usually caused by persistent cystic-duct obstruction by a gallstone. The diagnosis is supported by the combination of local right-upper-quadrant findings, systemi…12 min read
SurgeryAcute Colonic Diverticulitis in AdultsAcute colonic diverticulitis is inflammation of a colonic diverticulum and surrounding tissues. The key first decision is not “Which antibiotic?” but “Is this uncomplicated or complicated disease, and is the patient s…29 min read
OrthopedicsAcute Compartment Syndrome of the ExtremitiesAcute compartment syndrome (ACS) is a time-critical rise in pressure within a closed myofascial space that reduces tissue perfusion and can cause irreversible muscle and nerve injury. Fracture is a common trigger, esp…12 min read
CardiologyAcute Coronary SyndromeAcute coronary syndrome (ACS) is the clinical spectrum caused most often by acute coronary atherothrombosis after plaque rupture or erosion and includes ST-elevation myocardial infarction (STEMI), non-ST-elevation myo…19 min read
CardiologyAcute Decompensated Heart FailureAcute decompensated heart failure (ADHF) is new or worsening heart failure severe enough to require urgent treatment. Most hospitalized patients have congestion; a smaller, high-risk group has clinically important hyp…16 min read
PulmonologyAcute Exacerbation of Chronic Obstructive Pulmonary DiseaseAn acute exacerbation of chronic obstructive pulmonary disease (COPD) is a worsening of dyspnea and/or cough and sputum over several days, usually within 14 days, associated with increased airway and systemic inflamma…12 min read
NeurologyAcute Ischemic StrokeAcute ischemic stroke (AIS) is sudden neurological dysfunction caused by focal cerebral, retinal, or spinal cord ischemia, most often from arterial occlusion. The practical emergency question is not simply “is this a…24 min read
NephrologyAcute Kidney InjuryAcute kidney injury (AKI) is an abrupt decline in kidney function identified by a rise in serum creatinine and/or reduced urine output. The current established international definition remains the KDIGO 2012 definitio…29 min read
Vascular MedicineAcute Limb IschemiaAcute limb ischemia (ALI) is a sudden reduction in arterial perfusion that threatens limb viability, conventionally with symptoms present for less than 2 weeks. The clinical priority is not to prove the exact cause be…12 min read
GastroenterologyAcute Liver FailureAcute liver failure (ALF) is a rapidly evolving syndrome of severe hepatic dysfunction in a person without established cirrhosis, characterized by acute liver injury, coagulopathy—commonly INR ≥1.5—and hepatic encepha…14 min read
GastroenterologyAcute Lower Gastrointestinal Bleeding in AdultsAcute lower gastrointestinal bleeding (LGIB) usually presents with hematochezia, maroon stool, or passage of blood and clots per rectum. The immediate priorities are hemodynamic stabilization, identification of patien…20 min read
Vascular MedicineAcute Mesenteric IschemiaAcute mesenteric ischemia (AMI) is abrupt intestinal hypoperfusion severe enough to threaten bowel viability. The major mechanisms are superior mesenteric arterial embolism, acute arterial thrombosis, non-occlusive me…11 min read
$undefinedAcute Myeloid Leukemia in AdultsAcute myeloid leukemia (AML) is a genetically heterogeneous group of aggressive clonal myeloid neoplasms characterized by accumulation of immature myeloid cells, impaired normal hematopoiesis, and risks from cytopenia…32 min read
PediatricsAcute Otitis Media in ChildrenAcute otitis media (AOM) is acute inflammation of the middle ear with middle-ear effusion plus characteristic tympanic-membrane findings. Symptoms alone, or an erythematous tympanic membrane without effusion, are insu…11 min read
GastroenterologyAcute PancreatitisAcute pancreatitis is an acute inflammatory injury of the pancreas with a clinical spectrum ranging from a short, self-limited illness to necrotizing pancreatitis with persistent multiorgan failure. Diagnosis requires…17 min read
CardiologyAcute PericarditisAcute pericarditis is an inflammatory pericardial syndrome causing pleuritic or positional chest pain, with variable inflammatory-marker elevation, electrocardiographic changes, pericardial effusion, and imaging evide…15 min read
PulmonologyAcute Pulmonary EmbolismAcute pulmonary embolism (PE) is obstruction of the pulmonary arterial circulation by thrombus, usually arising from deep veins of the legs or pelvis. The immediate threat is acute right-ventricular (RV) pressure over…32 min read
Infectious DiseaseAcute Pyelonephritis in AdultsAcute pyelonephritis is bacterial infection of the renal parenchyma and collecting system, usually caused by ascending infection from the lower urinary tract. Fever, flank pain, costovertebral-angle tenderness, pyuria…13 min read
Critical CareAcute Respiratory Distress SyndromeAcute respiratory distress syndrome (ARDS) is acute diffuse inflammatory lung injury causing increased alveolar-capillary permeability, noncardiogenic pulmonary edema, loss of aerated lung, intrapulmonary shunt, reduc…13 min read
UrologyAcute Urinary Retention in AdultsAcute urinary retention (AUR) is the sudden inability to void despite a distended bladder. It is a urologic urgency because prolonged obstruction can cause severe pain, infection, hematuria, acute kidney injury, hydro…13 min read
EndocrinologyAdrenal CrisisAdrenal crisis is an acute, life-threatening state of inadequate glucocorticoid activity for the patient's physiologic stress, producing hypotension or shock, volume depletion, metabolic disturbance, and systemic illn…14 min read
$undefinedAlcohol Withdrawal Syndrome in AdultsAlcohol withdrawal syndrome (AWS) is a spectrum of autonomic, neurologic, and neuropsychiatric symptoms that can occur after abrupt cessation or substantial reduction of sustained heavy alcohol exposure. Mild withdraw…35 min read
HepatologyAlcohol-Associated HepatitisAlcohol-associated hepatitis (AH) is an acute inflammatory liver syndrome that typically presents with recent onset or worsening jaundice after sustained heavy alcohol exposure. The syndrome can occur with or without…13 min read
GeriatricsAlzheimer Disease and Mild Cognitive Impairment Due to Alzheimer DiseaseAlzheimer disease is a progressive neurodegenerative disease characterized biologically by amyloid-β and tau pathology and clinically by gradual decline in cognition and function. The classic phenotype begins with epi…30 min read
Allergy & ImmunologyAnaphylaxisAnaphylaxis is an acute systemic hypersensitivity reaction that can rapidly cause fatal airway obstruction, respiratory failure, or circulatory collapse. Skin or mucosal findings are common but may be absent, so their…14 min read
NephrologyAnemia in Chronic Kidney DiseaseAnemia is a common complication of chronic kidney disease (CKD) caused by reduced erythropoietin production, iron deficiency, inflammation-driven iron restriction, shortened erythrocyte survival, blood loss, and coexi…10 min read
NeurologyAneurysmal Subarachnoid HemorrhageAneurysmal subarachnoid hemorrhage (aSAH) is spontaneous bleeding into the subarachnoid space after rupture of an intracranial aneurysm. It is a time-critical neurovascular emergency with an overall case-fatality of a…15 min read
Allergy & ImmunologyAngioedemaAngioedema is transient swelling of deep dermal, subcutaneous, or submucosal tissue caused by increased vascular permeability. The clinically decisive distinction is between mast-cell–mediated angioedema, which often…17 min read
RheumatologyAntiphospholipid SyndromeAntiphospholipid syndrome (APS) is an acquired autoimmune thrombophilia defined clinically by arterial, venous, or microvascular thrombosis and/or characteristic pregnancy morbidity together with persistent antiphosph…11 min read
CardiologyAortic Regurgitation in AdultsAortic regurgitation (AR) is retrograde flow from the aorta into the left ventricle during diastole because of abnormal aortic valve cusps, dilation of the aortic root/ascending aorta, or both. The clinical distinctio…15 min read
$undefinedAortic Stenosis in AdultsAortic stenosis (AS) is a progressive obstruction to left-ventricular outflow caused most often by calcific degeneration of a tricuspid or bicuspid aortic valve. The clinical problem is not simply whether the valve is…25 min read
PulmonologyAsthma in Adults and AdolescentsAsthma is a heterogeneous chronic airway disease characterized by variable respiratory symptoms plus variable expiratory airflow limitation. Wheeze, dyspnea, chest tightness, and cough typically fluctuate over time an…29 min read
DermatologyAtopic DermatitisAtopic dermatitis (AD) is a chronic, relapsing, intensely pruritic inflammatory skin disease driven by epidermal-barrier dysfunction, type 2–skewed inflammation, neuroimmune itch, and environmental and microbial inter…14 min read
CardiologyAtrial FibrillationAtrial fibrillation (AF) is a supraventricular tachyarrhythmia characterized by chaotic atrial electrical activation and ineffective atrial contraction. On ECG it produces irregularly irregular RR intervals (when AV c…37 min read
PediatricsAttention-Deficit/Hyperactivity Disorder in Children and AdolescentsAttention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by developmentally inappropriate and persistent inattention and/or hyperactivity-impulsivity that begins in childhood, occ…36 min read
OphthalmologyBacterial KeratitisBacterial keratitis is infection of the corneal stroma, usually with an epithelial defect, stromal infiltrate, pain, photophobia, redness, tearing or discharge, and reduced vision. It can progress rapidly to stromal n…13 min read
OtolaryngologyBell Palsy in AdultsBell palsy is an acute, unilateral lower-motor-neuron facial nerve palsy with no identified alternative cause after focused clinical assessment. Weakness typically progresses over hours and reaches maximal severity wi…11 min read
UrologyBenign Prostatic Hyperplasia and Male Lower Urinary Tract SymptomsMale lower urinary tract symptoms (LUTS) are a syndrome, not a diagnosis. Storage symptoms include urgency, frequency, nocturia, and urgency incontinence; voiding symptoms include weak stream, hesitancy, intermittency…12 min read
PsychiatryBipolar I DisorderBipolar I disorder is defined by at least one lifetime manic episode. Mania is a distinct period of abnormally elevated, expansive, or irritable mood with persistently increased energy or activity, usually lasting at…14 min read
Hematology & OncologyBreast Cancer in AdultsBreast cancer is not one disease. The first point-of-care task is to define anatomic extent plus tumor biology: invasive versus in situ disease; histologic type and grade; estrogen receptor (ER), progesterone receptor…39 min read
PulmonologyBronchiectasis in AdultsBronchiectasis is a chronic airway disorder defined by permanent bronchial dilatation on chest CT together with a compatible clinical syndrome, usually chronic cough, sputum production, recurrent respiratory infection…12 min read
CardiologyCardiac Tamponade and Pericardial Effusion in AdultsCardiac tamponade is a clinical hemodynamic syndrome caused by pericardial pressure that impairs cardiac filling and reduces cardiac output. It is not defined by effusion size alone. A rapidly accumulating small effus…12 min read
Vascular MedicineCarotid Artery Stenosis in AdultsAtherosclerotic extracranial internal carotid artery stenosis is an important preventable cause of retinal and cerebral ischemia. The first decision is whether the lesion is symptomatic: ipsilateral transient monocula…15 min read
NeurologyCauda Equina SyndromeCauda equina syndrome (CES) is acute or subacute dysfunction of multiple lumbosacral nerve roots caused most often by severe central lumbar canal compression. The clinically decisive threats are new bladder dysfunctio…11 min read
GastroenterologyCeliac DiseaseCeliac disease is a chronic immune-mediated small-intestinal enteropathy triggered by gluten in genetically susceptible people. Presentations range from diarrhea and weight loss to iron deficiency, low bone density, e…12 min read
Infectious DiseaseCellulitis and Erysipelas in AdultsCellulitis is an acute, spreading bacterial infection of the dermis and subcutaneous tissue; erysipelas generally refers to a more superficial infection with prominent lymphatic involvement and a more sharply demarcat…19 min read
Obstetrics & GynecologyCervical CancerCervical cancer is an HPV-driven malignancy arising from the cervix, most often squamous cell carcinoma or adenocarcinoma. Persistent infection with oncogenic human papillomavirus (HPV) is responsible for almost all c…16 min read
CardiologyChronic Coronary Disease in AdultsChronic coronary disease (CCD) is the long-term clinical spectrum of coronary atherosclerosis and ischemic syndromes outside an acute coronary syndrome. It includes patients with prior myocardial infarction (MI) or re…25 min read
$undefinedChronic Hepatitis BChronic hepatitis B (CHB) is persistent hepatitis B virus (HBV) infection, usually demonstrated by hepatitis B surface antigen (HBsAg) for at least 6 months or by a compatible longitudinal serologic history. The centr…32 min read
$undefinedChronic Hepatitis CChronic hepatitis C is persistent infection with hepatitis C virus (HCV), an RNA virus that can cause progressive fibrosis, cirrhosis, hepatocellular carcinoma (HCC), extrahepatic disease, and onward transmission. Mod…24 min read
NephrologyChronic Kidney DiseaseChronic kidney disease (CKD) is an abnormality of kidney structure or function present for at least 3 months with implications for health. Classification uses Cause, GFR category, and Albuminuria category (CGA). An is…15 min read
Hematology & OncologyChronic Lymphocytic Leukemia and Small Lymphocytic LymphomaChronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) are the leukemic and predominantly tissue-based manifestations of the same mature B-cell neoplasm. CLL requires ≥5 × 10^9/L clonal B lymphocytes…37 min read
Hematology & OncologyChronic Myeloid Leukemia in AdultsChronic myeloid leukemia (CML) is a clonal myeloproliferative neoplasm driven by the BCR::ABL1 fusion, usually created by the Philadelphia chromosome translocation t(9;22)(q34;q11.2). Most patients present in chronic…17 min read
PulmonologyChronic Obstructive Pulmonary DiseaseChronic obstructive pulmonary disease (COPD) is a heterogeneous chronic lung disorder with persistent respiratory symptoms and airflow obstruction due to airway and/or alveolar abnormalities, usually after cumulative…12 min read
GastroenterologyChronic PancreatitisChronic pancreatitis is a fibroinflammatory pancreatic syndrome in which persistent injury produces irreversible structural damage, pain, ductal obstruction, exocrine pancreatic insufficiency (EPI), diabetes, and loca…12 min read
OtolaryngologyChronic Rhinosinusitis in AdultsChronic rhinosinusitis (CRS) is persistent inflammation of the nasal cavity and paranasal sinuses lasting more than 12 weeks, accompanied by compatible symptoms and objective evidence of sinonasal inflammation on ante…10 min read
Allergy & ImmunologyChronic Spontaneous UrticariaChronic spontaneous urticaria (CSU) is recurrent spontaneous wheals, angioedema, or both for more than 6 weeks without a reproducible specific external trigger. It is a mast-cell-driven disorder; autoimmune mechanisms…13 min read
Vascular MedicineChronic Venous Disease of the Lower LimbsChronic venous disease (CVD) of the lower limbs comprises symptoms and signs caused by sustained venous hypertension from superficial or deep venous reflux, venous outflow obstruction, calf-muscle-pump dysfunction, or…15 min read
GastroenterologyCirrhosis and Portal HypertensionCirrhosis is advanced chronic liver disease with architectural distortion, portal hypertension, impaired hepatic function, and systemic circulatory dysfunction. Clinical management is organized around disease stage: c…17 min read
Infectious DiseaseClostridioides difficile InfectionClostridioides difficile infection (CDI) is toxin-mediated colitis that usually follows disruption of the intestinal microbiota by antibiotics. Diagnosis requires a compatible clinical syndrome plus appropriate microb…14 min read
Hematology & OncologyColorectal Cancer in AdultsColorectal cancer (CRC) includes malignancies of the colon and rectum, most commonly adenocarcinoma. Although often grouped epidemiologically, colon and rectal cancers are managed differently because pelvic anatomy, l…20 min read
Infectious DiseaseCommunity-Acquired PneumoniaCommunity-acquired pneumonia (CAP) is an acute infection of the pulmonary parenchyma acquired outside the hospital setting. In adults, diagnosis generally requires a compatible acute respiratory syndrome plus a new pu…15 min read
PediatricsCroup in ChildrenCroup is an acute, usually viral upper-airway illness characterized by barking cough, hoarseness, inspiratory stridor, and variable respiratory distress. It most often affects children 6 months to 3 years old. Diagnos…14 min read
Vascular MedicineDeep Vein ThrombosisDeep vein thrombosis (DVT) is thrombus within the deep venous system, most often in the lower extremity. The immediate threat is pulmonary embolism (PE); longer-term risks include recurrent venous thromboembolism (VTE…16 min read
GeriatricsDelirium in AdultsDelirium is an acute, fluctuating disorder of attention, awareness, arousal, and cognition caused by one or more physiologic insults. It is a clinical syndrome, not a final etiologic diagnosis. Hypoactive delirium is…15 min read
Infectious DiseaseDiabetes-Related Foot InfectionDiabetes-related foot infection (DFI) is a clinical diagnosis made when a foot wound or adjacent tissue in a person with diabetes has local or systemic inflammatory features. Microbial growth from an ulcer does not by…17 min read
EndocrinologyDiabetic KetoacidosisDiabetic ketoacidosis (DKA) is an acute metabolic emergency caused by insufficient effective insulin activity together with excess counterregulatory hormones, producing ketogenesis, metabolic acidosis, osmotic diuresi…21 min read
NeurologyDiabetic Peripheral Neuropathy in AdultsDiabetic peripheral neuropathy (DPN) is a heterogeneous group of peripheral nerve disorders attributable to diabetes after other causes have been considered. The most common phenotype is distal symmetric polyneuropath…13 min read
OphthalmologyDiabetic Retinopathy and Diabetic Macular EdemaDiabetic retinopathy (DR) is a retinal microvascular and neurovascular complication of diabetes caused by chronic metabolic and vascular injury. It progresses from nonproliferative diabetic retinopathy (NPDR)—microane…36 min read
CardiologyDyslipidemia in AdultsDyslipidemia is an abnormal concentration or composition of circulating lipoproteins that increases atherosclerotic cardiovascular disease (ASCVD) risk or, when triglycerides are very high, pancreatitis risk. LDL-cont…17 min read
Obstetrics & GynecologyEctopic PregnancyEctopic pregnancy is implantation of a pregnancy outside the endometrial cavity. Most are tubal, but interstitial, cervical, cesarean-scar, ovarian, abdominal, and heterotopic pregnancies require special management. T…14 min read
Obstetrics & GynecologyEndometrial CancerEndometrial cancer is a malignant epithelial tumor arising from the endometrium. Most patients present with abnormal uterine bleeding, especially postmenopausal bleeding, and many are diagnosed while disease is confin…14 min read
Obstetrics & GynecologyEndometriosisEndometriosis is a chronic estrogen-responsive inflammatory disorder in which endometrial-like tissue is present outside the uterine cavity. The major clinical phenotypes are superficial peritoneal disease, ovarian en…16 min read
$undefinedEpilepsy in AdultsEpilepsy is not synonymous with “a seizure.” The ILAE practical definition allows diagnosis after: (1) at least two unprovoked or reflex seizures more than 24 hours apart; (2) one unprovoked or reflex seizure when the…31 min read
OtolaryngologyEpistaxis in AdultsEpistaxis is usually anterior and self-limited, but brisk posterior bleeding can cause major blood loss, aspiration, hemodynamic instability, and airway compromise. Management is stepwise: stabilize first when bleedin…11 min read
Obstetrics & GynecologyEpithelial Ovarian, Fallopian Tube, and Primary Peritoneal Cancer in AdultsEpithelial ovarian, fallopian tube, and primary peritoneal cancers are managed as a closely related group because most high-grade serous cancers arise from Müllerian epithelium and commonly present with transcoelomic…15 min read
Emergency MedicineEthylene Glycol PoisoningEthylene glycol poisoning is a time-critical toxic alcohol emergency. The parent alcohol causes early intoxication, but the major injury comes from metabolism by alcohol dehydrogenase to glycolic acid and oxalic acid,…11 min read
Hematology & OncologyFebrile NeutropeniaFebrile neutropenia is fever in a patient with severe neutropenia or impending severe neutropenia and is treated as an oncologic emergency because inflammatory signs may be muted while bacterial infection can progress…16 min read
GastroenterologyGastroesophageal Reflux Disease in AdultsGastroesophageal reflux disease (GERD) is present when reflux of gastric contents into the esophagus causes troublesome symptoms and/or complications. The core problem is failure of the antireflux barrier at the esoph…29 min read
PsychiatryGeneralized Anxiety Disorder in AdultsGeneralized anxiety disorder (GAD) is a persistent syndrome of difficult-to-control, excessive worry across multiple domains, accompanied by physical and cognitive hyperarousal and clinically important distress or imp…20 min read
$undefinedGestational Diabetes MellitusGestational diabetes mellitus (GDM) is diabetes diagnosed in the second or third trimester that was not clearly overt diabetes before pregnancy. It reflects pregnancy-related insulin resistance superimposed on inadequ…29 min read
RheumatologyGiant Cell ArteritisGiant cell arteritis (GCA) is an immune-mediated granulomatous vasculitis of medium and large arteries that occurs almost exclusively in adults aged 50 years or older. It commonly affects branches of the external caro…26 min read
RheumatologyGoutGout is an inflammatory crystal arthritis caused by deposition of monosodium urate (MSU) crystals in joints and periarticular tissues. Hyperuricemia promotes crystal formation but does not by itself establish gout. Du…13 min read
NeurologyGuillain–Barré SyndromeGuillain–Barré syndrome (GBS) is an acute immune-mediated polyradiculoneuropathy characterized by rapidly progressive limb weakness, reduced or absent reflexes, variable sensory symptoms, cranial neuropathies, autonom…14 min read
$undefinedHeart Failure With Preserved Ejection Fraction (HFpEF)Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome in which typical symptoms and/or signs of heart failure coexist with objective evidence of abnormal cardiac structure or function and eleva…26 min read
CardiologyHeart Failure With Reduced Ejection Fraction (HFrEF)Heart failure with reduced ejection fraction (HFrEF) is a clinical syndrome of current or prior heart-failure symptoms/signs with left ventricular ejection fraction (LVEF) ≤40% in the AHA/ACC/HFSA framework. Diagnosis…16 min read
GastroenterologyHelicobacter pylori Infection in AdultsHelicobacter pylori is a chronic gastric infection that causes active gastritis and is a major cause of peptic ulcer disease, gastric mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric adenocarcinoma. Once…37 min read
HematologyHemophilia A and BHemophilia A and B are inherited bleeding disorders caused by deficiency or dysfunction of coagulation factor VIII (FVIII) or factor IX (FIX), respectively. Both are usually X-linked. The bleeding phenotype is driven…13 min read
HepatologyHepatic Encephalopathy in CirrhosisHepatic encephalopathy (HE) in cirrhosis is a potentially reversible neuropsychiatric syndrome caused by liver dysfunction and portosystemic shunting after other causes of altered cognition have been excluded. Overt H…13 min read
HepatologyHepatocellular Carcinoma in AdultsHepatocellular carcinoma (HCC) is the dominant primary liver malignancy and usually arises in a chronically injured liver. Cirrhosis from any cause is the major risk state; chronic hepatitis B virus (HBV) infection ca…14 min read
Infectious DiseaseHerpes Zoster in AdultsHerpes zoster is reactivation of latent varicella-zoster virus (VZV), usually producing unilateral neuropathic pain followed by grouped vesicles in one or two adjacent dermatomes. The rash usually does not cross the m…12 min read
DermatologyHidradenitis SuppurativaHidradenitis suppurativa (HS) is a chronic, relapsing inflammatory follicular disease that produces painful nodules, abscesses, draining tunnels, and scarring in intertriginous skin. The diagnosis is clinical: charact…11 min read
$undefinedHip Fracture in Older AdultsHip fracture in an older adult is a time-sensitive surgical and geriatric emergency associated with pain, immobility, delirium, venous thromboembolism (VTE), pressure injury, pneumonia, loss of independence, recurrent…28 min read
Infectious DiseaseHIV Infection in AdultsHIV is a chronic retroviral infection that progressively depletes and dysregulates CD4 T lymphocytes unless viral replication is durably suppressed. Modern ART transforms HIV into a manageable chronic disease for most…30 min read
EndocrinologyHypercalcemia in AdultsHypercalcemia is an elevation of extracellular calcium that becomes clinically urgent when it is severe, rapidly rising, or associated with neurologic, cardiac, renal, or volume complications. Confirm that the abnorma…15 min read
Obstetrics & GynecologyHyperemesis GravidarumHyperemesis gravidarum (HG) is the severe end of nausea and vomiting of pregnancy, with persistent symptoms that impair normal eating and drinking and can cause dehydration, electrolyte disturbance, weight loss, malnu…15 min read
NephrologyHyperkalemiaHyperkalemia is an elevation in extracellular potassium that can produce rapidly fatal cardiac conduction abnormalities. Laboratory thresholds vary; the UK Kidney Association (UKKA) classifies adult hyperkalemia as mi…13 min read
EndocrinologyHyperosmolar Hyperglycemic StateHyperosmolar hyperglycemic state (HHS) is a life-threatening hyperglycemic emergency characterized by profound hyperglycemia, hyperosmolality, and severe volume depletion without the degree of ketonemia and metabolic…15 min read
Emergency MedicineHypertensive EmergenciesA hypertensive emergency is severe or rapidly rising blood pressure accompanied by new or worsening acute hypertension-mediated target-organ injury. The number alone does not establish the diagnosis. Acute brain injur…12 min read
CardiologyHypertensive EmergencyA hypertensive emergency is severe blood-pressure elevation accompanied by new or worsening acute target-organ damage. The number on the sphygmomanometer alone does not define the emergency. Acute encephalopathy, intr…25 min read
EndocrinologyHyperthyroidism and Graves Disease in AdultsThyrotoxicosis means excessive thyroid-hormone action; hyperthyroidism is thyrotoxicosis caused by increased hormone synthesis and secretion by the thyroid. Graves disease is the most common cause of hyperthyroidism i…26 min read
NephrologyHyponatremiaHyponatremia is serum sodium <135 mmol/L and usually reflects excess water relative to exchangeable sodium and potassium. The first two decisions are whether the patient has true hypotonic hyponatremia and whether neu…13 min read
EndocrinologyHypothyroidism in AdultsHypothyroidism is deficient thyroid-hormone action, most commonly from primary thyroid failure. In primary overt hypothyroidism, serum TSH is elevated and free T4 (FT4) is low; in subclinical hypothyroidism, TSH is el…34 min read
PulmonologyIdiopathic Pulmonary FibrosisIdiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrosing interstitial pneumonia of unknown cause that occurs primarily in older adults and is defined by the presence of a usual interstitial pneumonia (U…36 min read
NephrologyIgA NephropathyIgA nephropathy (IgAN) is an immune-complex glomerular disease defined by dominant or codominant IgA deposition in the glomerular mesangium on kidney biopsy. Presentation ranges from episodic visible hematuria during…11 min read
$undefinedImmune Thrombocytopenia (ITP)Immune thrombocytopenia (ITP) is an acquired immune-mediated disorder characterized by thrombocytopenia from accelerated platelet destruction and impaired platelet production. It remains a diagnosis of exclusion: ther…27 min read
HematologyImmune Thrombotic Thrombocytopenic PurpuraImmune thrombotic thrombocytopenic purpura (iTTP) is a life-threatening thrombotic microangiopathy caused by severe acquired deficiency of ADAMTS13, usually from inhibitory or clearance-enhancing autoantibodies. The r…16 min read
Infectious DiseaseInfective EndocarditisInfective endocarditis (IE) is microbial infection of the endocardial surface, usually involving a native or prosthetic valve or intracardiac device. Major hazards are acute valve failure, periannular extension, persi…14 min read
$undefinedInflammatory Bowel Disease in Adults: Ulcerative Colitis and Crohn DiseaseInflammatory bowel disease (IBD) comprises chronic immune-mediated intestinal inflammation, principally UC and CD. UC usually causes continuous mucosal inflammation beginning in the rectum and extending proximally thr…30 min read
Obstetrics & GynecologyIntrahepatic Cholestasis of PregnancyIntrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific cholestatic disorder characterized by pruritus with elevated serum bile acids after other causes have been excluded. Pruritus often affects the palms…9 min read
HematologyIron Deficiency AnemiaIron deficiency anemia (IDA) results when iron available for erythropoiesis is insufficient to sustain normal hemoglobin production. The clinical task has two parallel parts: replace iron and identify why iron was los…20 min read
PediatricsKawasaki DiseaseKawasaki disease (KD) is an acute febrile systemic vasculitis of childhood with a predilection for the coronary arteries. There is no single diagnostic test. Recognition depends on the clinical pattern, deliberate ass…10 min read
Hematology & OncologyLung Cancer in AdultsLung cancer is broadly divided into non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). NSCLC accounts for most cases and includes adenocarcinoma, squamous-cell carcinoma, and less common histologies…19 min read
PsychiatryMajor Depressive DisorderMajor depressive disorder (MDD) is a recurrent mood disorder defined by a depressive syndrome causing clinically important distress or functional impairment, with depressed mood and/or loss of interest or pleasure as…12 min read
Critical CareMechanical Ventilation in AdultsMechanical ventilation supports oxygenation and/or ventilation while the underlying disease is treated. It does not cure respiratory failure. The safest strategy is to define the physiologic problem, use the least inj…30 min read
HepatologyMetabolic Dysfunction-Associated Steatotic Liver DiseaseMetabolic dysfunction-associated steatotic liver disease (MASLD) is hepatic steatosis occurring in a person with at least one defined cardiometabolic risk factor and without a more appropriate dominant steatotic-liver…22 min read
NeurologyMigraine in AdultsMigraine is a recurrent neurologic disorder characterized by attacks of headache, sensory hypersensitivity, nausea, and sometimes reversible focal neurologic aura. Diagnosis is clinical. A stable, recurrent phenotype…10 min read
CardiologyMitral Regurgitation in AdultsMitral regurgitation (MR) is systolic retrograde flow from the left ventricle (LV) into the left atrium (LA). The clinically important distinction is between primary MR, caused by structural disease of the valve appar…15 min read
$undefinedMultiple MyelomaMultiple myeloma (MM) is a clonal plasma-cell malignancy defined by clonal bone-marrow plasma cells ≥10% or a biopsy-proven plasmacytoma plus at least one myeloma-defining event. Myeloma-defining events include attrib…26 min read
NeurologyMultiple Sclerosis in AdultsMultiple sclerosis (MS) is an immune-mediated disease of the central nervous system (CNS) characterized by focal inflammatory demyelination, axonal injury, gliosis, and variable neurodegeneration. Typical manifestatio…38 min read
NeurologyMyasthenia GravisMyasthenia gravis (MG) is an autoimmune disorder of the postsynaptic neuromuscular junction characterized by fluctuating, fatigable skeletal-muscle weakness. Ocular symptoms are common at onset; generalized disease ca…13 min read
CardiologyMyocarditis in AdultsMyocarditis is inflammatory injury of the myocardium caused by infectious, immune-mediated, toxic, drug-related, or other processes. Presentation ranges from mild chest pain with troponin elevation to acute heart fail…14 min read
Infectious DiseaseNative Vertebral Osteomyelitis in AdultsNative vertebral osteomyelitis (NVO), also called infectious spondylodiscitis or discitis-osteomyelitis, is infection of a vertebral body/endplate with frequent spread into the adjacent disc and paraspinal or epidural…16 min read
SurgeryNecrotizing Soft Tissue InfectionNecrotizing soft tissue infection (NSTI) is a rapidly progressive infection of fascia, subcutaneous tissue, or muscle that causes thrombosis, tissue necrosis, systemic toxicity, and high mortality. The diagnosis is pr…11 min read
$undefinedNeonatal Hyperbilirubinemia in Infants ≥35 Weeks’ GestationNeonatal jaundice is common: more than 80% of newborns develop some degree of visible jaundice. Most cases are benign, but sufficiently high unconjugated bilirubin can cross the blood-brain barrier and produce acute b…38 min read
PediatricsNeonatal SepsisNeonatal sepsis is a life-threatening systemic infection syndrome in the first 28 days of life; many guidelines extend serious-bacterial-infection pathways through 59 or 89 days for young infants. Early-onset infectio…14 min read
UrologyNephrolithiasis (Kidney and Ureteral Stones)Nephrolithiasis is formation of calculi in the kidney or ureter. The immediate clinical task is not simply to confirm a stone; it is to identify infected obstruction, anuria, threatened renal function, a solitary func…19 min read
$undefinedNephrotic Syndrome in AdultsNephrotic syndrome is a clinicopathologic syndrome, not a diagnosis. It is characterized by heavy glomerular protein loss, hypoalbuminemia, edema, and usually hyperlipidemia/lipiduria. In adults, nephrotic-range prote…26 min read
EndocrinologyObesity in AdultsObesity is a chronic, relapsing disease of excess adiposity that increases risk of type 2 diabetes, cardiovascular disease, sleep apnea, metabolic liver disease, osteoarthritis, infertility, several cancers, and prema…17 min read
$undefinedObstructive Sleep Apnea in AdultsObstructive sleep apnea (OSA) is a chronic sleep-related breathing disorder caused by recurrent partial or complete upper-airway collapse during sleep. The resulting episodes of airflow reduction or cessation produce…35 min read
OrthopedicsOpen Fractures in AdultsAn open fracture is a fracture that communicates with the external environment through a wound. The skin opening may be small and remote from the fracture line, so any wound in the same limb segment as a fracture shou…15 min read
RheumatologyOsteoarthritisOsteoarthritis (OA) is a whole-joint disorder involving cartilage, subchondral bone, synovium, ligaments, menisci or labrum, capsule, and periarticular muscle. It causes activity-related pain, brief stiffness, functio…11 min read
EndocrinologyOsteoporosisOsteoporosis is a skeletal disorder in which reduced bone strength increases fragility-fracture risk. It is usually silent until fracture. Hip and vertebral fractures carry the greatest morbidity, but distal radius, p…13 min read
$undefinedParkinson Disease in AdultsParkinson disease (PD) is a progressive neurodegenerative syndrome defined clinically by parkinsonism—bradykinesia plus rest tremor, rigidity, or both—in the setting of a pattern most consistent with idiopathic PD. Th…37 min read
Obstetrics & GynecologyPelvic Inflammatory DiseasePelvic inflammatory disease (PID) is infection and inflammation of the upper female genital tract, including endometritis, salpingitis, tubo-ovarian abscess (TOA), and pelvic peritonitis. It is usually polymicrobial.…11 min read
Vascular MedicinePeripheral Artery DiseaseLower-extremity peripheral artery disease (PAD) is atherosclerotic or thrombotic obstruction of arteries supplying the legs. It is both a limb disorder and a marker of systemic vascular disease, with increased risk of…13 min read
PulmonologyPleural Effusion in AdultsPleural effusion is abnormal fluid accumulation in the pleural space. The bedside priorities are to identify respiratory compromise, decide whether fluid sampling is needed, separate transudative from exudative physio…12 min read
$undefinedPolycystic Ovary SyndromePolycystic ovary syndrome (PCOS) is a heterogeneous endocrine-metabolic disorder characterized by combinations of hyperandrogenism, ovulatory dysfunction, and polycystic ovarian morphology (PCOM) after exclusion of im…30 min read
RheumatologyPolymyalgia RheumaticaPolymyalgia rheumatica (PMR) is an inflammatory syndrome of adults aged 50 years or older characterized by bilateral shoulder-girdle pain and marked morning stiffness, often with hip-girdle or neck symptoms and elevat…15 min read
Obstetrics & GynecologyPostpartum HemorrhagePostpartum hemorrhage (PPH) is acute bleeding after birth that threatens maternal physiology. Recognition and treatment must occur before cardiovascular collapse, because pregnancy-related physiologic reserve can mask…17 min read
Obstetrics & GynecologyPreeclampsia and EclampsiaPreeclampsia is a pregnancy-specific multisystem disorder characterized by new hypertension after 20 weeks of gestation with proteinuria and/or maternal organ dysfunction. Proteinuria is not required when qualifying t…17 min read
EndocrinologyPrimary Adrenal Insufficiency in AdultsPrimary adrenal insufficiency (PAI) is failure of the adrenal cortex to produce adequate glucocorticoids and, in most acquired cases, mineralocorticoids. Autoimmune adrenalitis is the leading cause in adults in many h…16 min read
EndocrinologyPrimary AldosteronismPrimary aldosteronism (PA) is autonomous or inappropriately high aldosterone production from one or both adrenal glands, causing renal sodium retention, hypertension, potassium wasting in a subset of patients, and sup…11 min read
HepatologyPrimary Biliary CholangitisPrimary biliary cholangitis (PBC) is a chronic autoimmune cholestatic liver disease characterized by progressive injury and loss of small intrahepatic bile ducts. Untreated or inadequately controlled disease can progr…15 min read
EndocrinologyPrimary HyperparathyroidismPrimary hyperparathyroidism (PHPT) is autonomous or relatively autonomous parathyroid hormone (PTH) secretion, most often from a solitary adenoma and less often from multigland disease. In classic PHPT, albumin-adjust…12 min read
CardiologyPrimary Hypertension in AdultsPrimary hypertension is sustained elevation of arterial pressure without a single dominant reversible cause. It is usually asymptomatic, but cumulative exposure drives stroke, coronary disease, heart failure, atrial f…14 min read
OphthalmologyPrimary Open-Angle GlaucomaPrimary open-angle glaucoma (POAG) is a chronic progressive optic neuropathy with characteristic retinal ganglion-cell/axonal loss and corresponding visual-field damage in an eye with an open anterior-chamber angle an…12 min read
HepatologyPrimary Sclerosing CholangitisPrimary sclerosing cholangitis (PSC) is a chronic fibroinflammatory cholangiopathy characterized by multifocal intrahepatic and/or extrahepatic bile-duct stricturing. It is strongly associated with inflammatory bowel…11 min read
RheumatologyPrimary Sjögren DiseasePrimary Sjögren disease is a chronic systemic autoimmune disorder characterized by lymphocytic injury to exocrine glands, most prominently the lacrimal and salivary glands, with frequent extraglandular disease. Dry ey…12 min read
EndocrinologyProlactinoma and Hyperprolactinemia in AdultsHyperprolactinemia is a biochemical finding with physiologic, drug-related, systemic, and pituitary causes. A prolactinoma is a lactotroph pituitary neuroendocrine tumor that causes sustained prolactin excess and, whe…13 min read
UrologyProstate Cancer in AdultsProstate cancer is predominantly an adenocarcinoma of the peripheral prostate and ranges from indolent localized disease that may never threaten life to rapidly progressive metastatic cancer. Management is therefore d…18 min read
$undefinedPsoriasisPsoriasis is a chronic, immune-mediated inflammatory disease characterized by sharply demarcated erythematous or violaceous plaques with scale, most often involving extensor surfaces, scalp, umbilicus, gluteal cleft,…24 min read
PulmonologyPulmonary Hypertension in AdultsPulmonary hypertension (PH) is defined hemodynamically by a mean pulmonary artery pressure (mPAP) >20 mmHg at rest on right-heart catheterization. It is divided into five clinical groups because mechanism determines t…45 min read
NeurologyRestless Legs Syndrome in AdultsRestless legs syndrome (RLS), also called Willis-Ekbom disease, is a sensorimotor disorder characterized by an urge to move the legs, usually accompanied by uncomfortable sensations, that begins or worsens during rest…12 min read
OphthalmologyRetinal DetachmentRetinal detachment is separation of the neurosensory retina from the retinal pigment epithelium. Rhegmatogenous retinal detachment (RRD), caused by a full-thickness retinal break that allows liquefied vitreous to ente…10 min read
Emergency MedicineRhabdomyolysisRhabdomyolysis is acute skeletal-muscle injury with release of intracellular contents, especially creatine kinase (CK), potassium, phosphate, urate, and myoglobin. The major immediate threats are hyperkalemia, acute k…12 min read
RheumatologyRheumatoid ArthritisRheumatoid arthritis (RA) is a chronic immune-mediated inflammatory arthritis characterized by persistent synovitis with potential for erosive joint damage, tendon injury, deformity, disability, and systemic disease.…15 min read
PulmonologySarcoidosis in AdultsSarcoidosis is a multisystem granulomatous disease of uncertain cause characterized by non-necrotizing granulomatous inflammation. The lungs and intrathoracic lymph nodes are affected most often, but skin, eyes, heart…13 min read
PsychiatrySchizophreniaSchizophrenia is a chronic psychotic disorder characterized by combinations of delusions, hallucinations, disorganized thought or behavior, negative symptoms, cognitive impairment, and clinically important functional…13 min read
Critical CareSepsis and Septic ShockSepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection. Operationally, Sepsis-3 identifies organ dysfunction as an acute increase in SOFA score ≥2 points attributable to infec…24 min read
OrthopedicsSeptic Arthritis of a Native JointSeptic arthritis of a native joint is an infection of synovium and joint fluid, usually bacterial, that can destroy cartilage rapidly and can accompany bacteremia, sepsis, periarticular abscess, or osteomyelitis. Any…12 min read
HematologySickle Cell DiseaseSickle cell disease (SCD) is a group of inherited hemoglobin disorders in which hemoglobin S (HbS) polymerizes when deoxygenated, causing red-cell deformation, hemolysis, inflammation, endothelial adhesion, vaso-occlu…14 min read
SurgerySmall Bowel ObstructionSmall bowel obstruction (SBO) is impaired passage of intestinal contents through the small bowel, most often from a mechanical transition point. In adults, postoperative adhesions are the leading cause in many setting…13 min read
HepatologySpontaneous Bacterial PeritonitisSpontaneous bacterial peritonitis (SBP) is infection of ascitic fluid without a surgically treatable intra-abdominal source. It occurs most often in decompensated cirrhosis and is a medical emergency because renal fai…12 min read
NeurologySpontaneous Intracerebral HemorrhageSpontaneous intracerebral hemorrhage (ICH) is nontraumatic bleeding into brain parenchyma. Early priorities are rapid noncontrast head CT, airway and physiologic stabilization, smooth blood-pressure control, immediate…14 min read
PulmonologySpontaneous Pneumothorax in AdultsSpontaneous pneumothorax is air in the pleural space occurring without trauma or a recent causative procedure. It is classified as primary spontaneous pneumothorax (PSP) when there is no clinically established underly…12 min read
NeurologyStatus EpilepticusStatus epilepticus (SE) is a time-critical neurologic emergency caused by failure of normal seizure-termination mechanisms or by mechanisms that sustain abnormally prolonged seizure activity. For bilateral tonic-cloni…16 min read
DermatologyStevens-Johnson Syndrome and Toxic Epidermal NecrolysisStevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severity forms of epidermal necrolysis, a rare, predominantly drug-triggered, life-threatening mucocutaneous reaction characterized by painful ke…15 min read
OtolaryngologySudden Sensorineural Hearing Loss in AdultsSudden sensorineural hearing loss (SSNHL) is an otologic urgency: a rapid loss of cochlear or neural hearing, usually unilateral, developing over hours to a few days. A widely used research definition is a ≥30 dB sens…10 min read
CardiologySupraventricular Tachycardia in AdultsSupraventricular tachycardia (SVT) is a group of rapid rhythms arising above the ventricles. In acute care, the clinically important first distinction is not the exact mechanism but whether the tachyarrhythmia is caus…12 min read
CardiologySyncope in AdultsSyncope is transient loss of consciousness caused by global cerebral hypoperfusion, with rapid onset, short duration, and spontaneous complete recovery. The first task is to identify immediately dangerous causes: mali…11 min read
Infectious DiseaseSyphilis in AdultsSyphilis is a systemic infection caused by Treponema pallidum. Clinical disease is staged as primary, secondary, latent, or tertiary, but neurologic, ocular, and otic involvement can occur at any stage. Diagnosis gene…15 min read
RheumatologySystemic Lupus ErythematosusSystemic lupus erythematosus (SLE) is a chronic autoimmune disease with highly variable involvement of skin, joints, blood cells, kidneys, nervous system, lungs, heart, and blood vessels. Diagnosis is clinical and req…13 min read
RheumatologySystemic SclerosisSystemic sclerosis (SSc) is a heterogeneous autoimmune connective-tissue disease characterized by vasculopathy, immune dysregulation, and progressive fibrosis of skin and internal organs. The two major cutaneous subse…16 min read
UrologyTesticular TorsionTesticular torsion is rotation of the spermatic cord causing venous obstruction, progressive edema, impaired arterial inflow, ischemia, and possible testicular infarction. It is a surgical emergency. The classic patte…13 min read
EndocrinologyThyroid StormThyroid storm is acute, life-threatening decompensation of thyrotoxicosis with systemic organ dysfunction. It is a clinical diagnosis: no TSH, free T4, or free T3 concentration reliably separates storm from severe unc…16 min read
NeurologyTransient Ischemic Attack in AdultsA transient ischemic attack (TIA) is a transient focal neurologic syndrome caused by cerebral, spinal, or retinal ischemia without acute infarction on tissue-based assessment. It is a medical emergency because the ris…13 min read
Infectious DiseaseTuberculosis: Infection and Active DiseaseTuberculosis exists on a spectrum from TB infection without clinical disease to microbiologically or clinically active disease. A positive interferon-gamma release assay (IGRA) or tuberculin skin test (TST) indicates…30 min read
Hematology & OncologyTumor Lysis SyndromeTumor lysis syndrome (TLS) is an oncologic metabolic emergency caused by rapid malignant-cell breakdown with release of potassium, phosphate, and nucleic acids. The major immediate threats are hyperkalemia, hyperphosp…13 min read
EndocrinologyType 1 Diabetes Mellitus in AdultsType 1 diabetes mellitus (T1D) is an immune-mediated disorder characterized by progressive destruction or dysfunction of pancreatic beta cells, leading to absolute or near-absolute insulin deficiency. It can develop a…26 min read
EndocrinologyType 2 Diabetes MellitusType 2 diabetes mellitus (T2D) is chronic hyperglycemia caused by progressive beta-cell dysfunction on a background of insulin resistance and broader metabolic dysregulation. Diagnosis in a nonpregnant person is estab…15 min read
GastroenterologyUpper Gastrointestinal BleedingUpper gastrointestinal bleeding (UGIB) is bleeding arising proximal to the ligament of Treitz. It most commonly presents with hematemesis, coffee-ground emesis, melena, or—when brisk—hematochezia with hemodynamic inst…22 min read
PediatricsUrinary Tract Infection in ChildrenUrinary tract infection (UTI) in children includes lower-tract infection and febrile/upper-tract infection involving the kidney. Presentation changes markedly with age: infants may have fever, poor feeding, vomiting,…15 min read
Infectious DiseaseUrinary Tract Infections in AdultsUrinary tract infection (UTI) is a symptomatic infection of the bladder, upper urinary tract, or related urinary structures. The first bedside decision is whether illness is localized to the bladder or represents syst…14 min read
HematologyVitamin B12 Deficiency in AdultsVitamin B12 deficiency is a potentially reversible cause of hematologic, neurologic, psychiatric, and mucosal disease. Neurologic injury can occur without anemia or macrocytosis; a normal mean corpuscular volume there…10 min read