STEPTRACKERPATHOLOGY | HIGH-YIELD REVIEW | USMLE STEP 1

Pathology Rapid Review

PART IGeneral PathologyChapters 01–03 · 26 pages
01

Cell Injury & Adaptation

8 pages
1.01Growth adaptationsHypertrophy · hyperplasia · atrophy · metaplasia · dysplasia — reversible vs notOpen →1.02Reversible vs irreversible injuryATP loss, cell swelling, membrane damage, enzyme leak markersOpen →1.03Necrosis patternsCoagulative · liquefactive · caseous · fat · fibrinoid · gangrenousOpen →1.04ApoptosisIntrinsic (BCL2, cytochrome c) vs extrinsic (Fas, TNF) · caspases · morphologyOpen →1.05Free radical injuryROS sources, scavengers, reperfusion, CCl4, iron & copper overloadOpen →1.06Hypoxia & ischemiaHypoxemia vs ↓O2 carrying (CO, MetHb) vs use (cyanide) · watershed zonesOpen →1.07AmyloidosisAL · AA · ATTR · β2-microglobulin · Aβ · IAPP · Congo red apple-greenOpen →1.08Calcification & pigmentsDystrophic vs metastatic · psammoma bodies · lipofuscin · hemosiderinOpen →
02

Inflammation, Immunopathology & Repair

11 pages
2.01Acute inflammation mediatorsArachidonic acid products · complement · kinins · mast cell releaseOpen →2.02Neutrophil arrival & killingRolling (selectins) · adhesion (integrins) · transmigration · O2-dependent killingOpen →2.03Phagocyte defectsLAD type 1 · Chédiak-Higashi · CGD · MPO deficiencyOpen →2.04Chronic & granulomatous inflammationMacrophage–Th1 axis · caseating vs noncaseating causes · IFN-γ, TNFOpen →2.05Systemic signs & acute-phase reactantsIL-1/IL-6/TNF · fever · CRP, ESR, ferritin, hepcidinOpen →2.06Wound healing & scarPhases · growth factors · collagen types · keloid vs hypertrophic scarOpen →2.07Primary immunodeficienciesBruton · DiGeorge · SCID · Wiskott-Aldrich · hyper-IgM · CVID · complementOpen →2.08Hypersensitivity typesType I–IV mechanisms, timing, examples, test findingsOpen →2.09Transplant rejection & GVHDHyperacute · acute · chronic · graft-versus-hostOpen →2.10Autoimmune disease I — SLE spectrumSLE · drug-induced lupus · antiphospholipid syndrome · antibodiesOpen →2.11Autoimmune disease IISjögren · systemic sclerosis (diffuse vs limited/CREST) · MCTDOpen →
03

Neoplasia

7 pages
3.01Benign vs malignant & nomenclatureHistologic features · -oma vs carcinoma vs sarcoma · exceptionsOpen →3.02Carcinogens & oncogenic virusesChemical · radiation · HPV, EBV, HBV/HCV, HTLV-1, HHV-8Open →3.03OncogenesRAS · MYC · HER2 · BCR-ABL · KIT · RET · BCL2 — mechanism and tumorOpen →3.04Tumor suppressors & DNA repairRB · TP53 · APC · BRCA · mismatch repair · two-hit modelOpen →3.05Invasion, metastasis, grade & stageSteps of spread · routes · TNM · stage beats gradeOpen →3.06Tumor markers & IHC stainsSerum markers by tumor · intermediate filaments · other key stainsOpen →3.07Paraneoplastic syndromes & cancer epidemiologyHormonal & neurologic syndromes · incidence vs mortalityOpen →
PART IIBlood & HemostasisChapters 04–06 · 28 pages
04

Hemostasis & Thrombosis

6 pages
4.01Hemostasis & coagulation testsPrimary vs secondary · cascade · PT, PTT, bleeding time, platelet countOpen →4.02Platelet disordersITP · TTP · HUS · Bernard-Soulier · Glanzmann · uremia, aspirinOpen →4.03Coagulation factor disordersHemophilia A/B · von Willebrand disease · vitamin K deficiency · liver diseaseOpen →4.04DIC & fibrinolysisTriggers · lab pattern · D-dimer · excess fibrinolysisOpen →4.05ThrombophiliasFactor V Leiden · prothrombin mutation · AT III, protein C/S deficiency · HITOpen →4.06EmbolismDVT → PE · fat · amniotic fluid · air · Virchow triadOpen →
05

Red Blood Cell Disorders

11 pages
5.01Approach to anemiaMCV split · reticulocyte index · production vs destructionOpen →5.02Iron deficiency vs anemia of chronic diseaseIron studies table · hepcidin · stages of iron lossOpen →5.03Thalassemiasα (gene deletions) vs β (mutations) · HbH, Bart, major, minor, electrophoresisOpen →5.04Sideroblastic anemia & lead poisoningHeme synthesis defects · ringed sideroblasts · basophilic stipplingOpen →5.05Macrocytic anemiasB12 vs folate (MMA, homocysteine) · pernicious anemia · nonmegaloblasticOpen →5.06Hemolysis basics & hereditary spherocytosisExtravascular vs intravascular signs · membrane defects · EMA testOpen →5.07Sickle cell disease & HbCPathogenesis · crises · complications · trait vs diseaseOpen →5.08G6PD, pyruvate kinase deficiency & PNHHeinz bodies, bite cells · ATP loss · CD55/59 lossOpen →5.09Immune & microangiopathic hemolysisWarm vs cold AIHA · Coombs · schistocyte causesOpen →5.10Marrow failure & polycythemiaAplastic anemia · pure red cell aplasia · primary vs secondary polycythemiaOpen →5.11RBC morphology atlasSmear finding → disease, drawn as schematicsOpen →
06

White Blood Cell Disorders

11 pages
6.01Leukopenia, leukocytosis & leukemoid reactionCauses by cell line · leukemoid vs CML (LAP)Open →6.02Acute leukemiasAML (Auer rods, APL t(15;17)) vs ALL (TdT, B vs T, t(12;21), t(9;22))Open →6.03Chronic leukemiasCLL (smudge cells) · hairy cell (TRAP, BRAF) · CML (BCR-ABL)Open →6.04Myeloproliferative neoplasmsPV · essential thrombocythemia · myelofibrosis · JAK2 · CML contrastOpen →6.05Myelodysplastic syndromes & lymphadenopathyMDS features · reactive node patterns (follicular, paracortical, sinus)Open →6.06Non-Hodgkin lymphoma I — small cellFollicular · mantle cell · marginal zone (MALT) · small lymphocyticOpen →6.07Non-Hodgkin lymphoma II — aggressive & T-cellBurkitt · DLBCL · ATLL · mycosis fungoides / SézaryOpen →6.08Hodgkin lymphomaReed-Sternberg cells · subtypes · B symptoms · vs NHLOpen →6.09Plasma cell dyscrasiasMultiple myeloma · MGUS · Waldenström · AL amyloid linkOpen →6.10Histiocytic & mast cell disordersLangerhans cell histiocytosis (Birbeck granules) · mastocytosisOpen →6.11Translocations & markers in heme-oncTranslocation → gene → disease · CD markers summaryOpen →
PART IIISystemic PathologyChapters 07–18 · 123 pages
07

Vascular Pathology

8 pages
7.01Large-vessel vasculitisGiant cell arteritis vs TakayasuOpen →7.02Medium-vessel vasculitisPolyarteritis nodosa · Kawasaki · BuergerOpen →7.03Small-vessel vasculitis — ANCAGPA · microscopic polyangiitis · EGPAOpen →7.04Small-vessel vasculitis — immune complexIgA vasculitis · cryoglobulinemia · Behçet · hypersensitivityOpen →7.05Hypertension & arteriolosclerosisHyaline vs hyperplastic · end-organ damage · malignant HTNOpen →7.06AtherosclerosisRisk factors · plaque evolution · complications · Mönckeberg contrastOpen →7.07Aneurysms & aortic dissectionAAA · thoracic · berry · dissection types · associated syndromesOpen →7.08Vascular tumorsHemangiomas · angiosarcoma · Kaposi sarcoma · bacillary angiomatosis · glomusOpen →
08

Cardiac Pathology

10 pages
8.01Ischemic heart diseaseStable · unstable · Prinzmetal angina · sudden cardiac deathOpen →8.02Myocardial infarction timelineGross & microscopic changes by time · markers · ECG localizationOpen →8.03MI complicationsArrhythmia · rupture types · aneurysm · Dressler — by time windowOpen →8.04Heart failureLeft vs right · systolic vs diastolic · organ findingsOpen →8.05Congenital heart disease — L→R shuntsVSD · ASD · PDA · EisenmengerOpen →8.06Congenital heart disease — cyanotic & coarctationThe five Ts · coarctation types · syndrome associationsOpen →8.07Valvular disease & murmursStenosis vs regurgitation of each valve · causes · maneuversOpen →8.08Rheumatic fever & endocarditisJones criteria · Aschoff bodies · acute vs subacute IE · organismsOpen →8.09Cardiomyopathies & myocarditisDilated · hypertrophic · restrictive · arrhythmogenic · myocarditisOpen →8.10Pericardial disease & cardiac tumorsPericarditis · tamponade · constriction · myxoma · rhabdomyomaOpen →
09

Respiratory Pathology

11 pages
9.01Upper airway & nasopharynxNasal polyps · angiofibroma · nasopharyngeal carcinoma · laryngeal lesionsOpen →9.02Pneumonia patterns & organismsLobar · bronchopneumonia · interstitial · aspiration · by hostOpen →9.03TuberculosisPrimary vs secondary · Ghon complex · granulomas · extrapulmonary sitesOpen →9.04Emphysema & chronic bronchitisCentriacinar vs panacinar · α1-antitrypsin · Reid indexOpen →9.05Asthma & bronchiectasisTh2 mechanism · Curschmann spirals · causes of bronchiectasisOpen →9.06Restrictive lung diseaseIdiopathic pulmonary fibrosis · pneumoconioses · drug-induced fibrosisOpen →9.07Sarcoidosis & hypersensitivity pneumonitisNoncaseating granulomas · ACE, Ca²⁺ · antigen exposuresOpen →9.08Pulmonary vascular diseasePulmonary hypertension groups · PE · cor pulmonaleOpen →9.09ARDS & neonatal respiratory distressDiffuse alveolar damage · hyaline membranes · surfactantOpen →9.10Lung cancerAdenocarcinoma · squamous · small cell · large cell · carcinoid · location & syndromesOpen →9.11Pleural diseaseTransudate vs exudate · pneumothorax types · mesotheliomaOpen →
10

Gastrointestinal Pathology

13 pages
10.01Oral cavity & salivary glandsLeukoplakia · oral SCC · pleomorphic adenoma · Warthin · mucoepidermoidOpen →10.02Esophagus I — structural & motilityAchalasia · Zenker · webs · Mallory-Weiss · Boerhaave · varicesOpen →10.03Esophagus II — esophagitis, Barrett & cancerReflux · eosinophilic · infectious · adenocarcinoma vs SCCOpen →10.04Stomach I — gastritisAcute erosive · H pylori · autoimmune · MénétrierOpen →10.05Stomach II — ulcers & gastric cancerGastric vs duodenal ulcer · complications · intestinal vs diffuse cancerOpen →10.06MalabsorptionCeliac disease · lactase deficiency · Whipple · tropical sprue · abetalipoproteinemiaOpen →10.07Small bowel disordersObstruction · intussusception · volvulus · ischemic bowel · MeckelOpen →10.08Inflammatory bowel diseaseCrohn disease vs ulcerative colitis — every feature side by sideOpen →10.09Pediatric GIPyloric stenosis · Hirschsprung · atresias · NEC · malrotationOpen →10.10Colon disordersDiverticulosis/itis · angiodysplasia · appendicitis · microscopic colitisOpen →10.11Polyps & polyposis syndromesHyperplastic vs adenomatous · FAP · Gardner · Turcot · Peutz-Jeghers · juvenileOpen →10.12Colorectal carcinomaAdenoma-carcinoma vs microsatellite pathways · right vs left · LynchOpen →10.13Neuroendocrine & stromal tumorsCarcinoid tumor & syndrome · GIST (KIT)Open →
11

Pancreas, Gallbladder & Liver

10 pages
11.01PancreatitisAcute (causes, labs, complications) vs chronicOpen →11.02Pancreatic neoplasmsAdenocarcinoma · cystic tumors · islet-cell tumorsOpen →11.03Gallbladder & biliary stonesStone types · cholecystitis · choledocholithiasis · cholangitis · carcinomaOpen →11.04Jaundice & hyperbilirubinemiasUnconjugated vs conjugated · Gilbert · Crigler-Najjar · Dubin-Johnson · RotorOpen →11.05Liver injury patternsHepatocellular vs cholestatic labs · drug & toxin injuryOpen →11.06Viral hepatitisA–E features · HBV serology timeline · chronic outcomesOpen →11.07Alcoholic & fatty liver disease, cirrhosisSteatosis → hepatitis → cirrhosis · NAFLD · portal hypertensionOpen →11.08Inherited & metabolic liver diseaseHemochromatosis · Wilson · α1-antitrypsin deficiency · ReyeOpen →11.09Cholestatic & biliary diseasesPBC · PSC · biliary atresiaOpen →11.10Liver tumors & vascular disordersHCC · hepatic adenoma · hemangioma · Budd-Chiari · metastasesOpen →
12

Kidney & Urinary Tract

12 pages
12.01Congenital & cystic kidney diseaseHorseshoe kidney · agenesis · ADPKD vs ARPKD · medullary cysticOpen →12.02Acute kidney injuryPrerenal vs intrinsic vs postrenal · BUN:Cr · FENa · ATN phasesOpen →12.03Interstitial nephritis & papillary necrosisDrug-induced AIN · papillary necrosis · Fanconi · RTA types 1, 2, 4Open →12.04Nephrotic syndrome IMinimal change · FSGS · membranous nephropathyOpen →12.05Nephrotic syndrome IIMembranoproliferative · diabetic nephropathy · amyloid · lupus classes IV & VOpen →12.06Nephritic syndrome IPoststreptococcal GN · IgA nephropathy · AlportOpen →12.07Nephritic syndrome II — RPGNAnti-GBM · immune complex · pauci-immune · crescentsOpen →12.08Urinalysis & castsCast type → location → diseaseOpen →12.09Kidney stonesCalcium · struvite · uric acid · cystine — causes, crystals, imagingOpen →12.10Chronic kidney diseaseConsequences: anemia, bone disease, uremia, acidosisOpen →12.11Urinary tract infection & obstructionCystitis vs pyelonephritis · hydronephrosis · refluxOpen →12.12Renal & urothelial tumorsRCC · oncocytoma · angiomyolipoma · Wilms · urothelial carcinomaOpen →
13

Female Genital Tract, Pregnancy & Breast

11 pages
13.01Vulva & vaginaLichen sclerosus · vulvar carcinoma · Paget · clear cell adenocarcinoma · sarcoma botryoidesOpen →13.02CervixHPV types · CIN grades · squamous carcinoma · screening logicOpen →13.03EndometriumHyperplasia · carcinoma types · endometriosis · adenomyosis · polypsOpen →13.04MyometriumLeiomyoma vs leiomyosarcoma · stromal sarcoma · Müllerian anomaliesOpen →13.05Ovary — non-neoplasticFollicular & corpus luteum cysts · PCOS · torsionOpen →13.06Ovarian epithelial tumorsSerous · mucinous · endometrioid · clear cell · Brenner · markersOpen →13.07Ovarian germ cell & sex cord–stromal tumorsTeratoma · dysgerminoma · yolk sac · granulosa · Sertoli-Leydig · fibromaOpen →13.08Pregnancy pathologyEctopic · placenta previa/accreta/abruption · preeclampsia, HELLPOpen →13.09Gestational trophoblastic diseaseComplete vs partial mole · choriocarcinomaOpen →13.10Benign breast diseaseFibrocystic change · fibroadenoma · intraductal papilloma · phyllodes · mastitisOpen →13.11Breast carcinomaDCIS · LCIS · invasive types · receptors · risk factors · inflammatory, PagetOpen →
14

Male Genital Tract

6 pages
14.01Penis & urethraHypospadias · epispadias · penile SCC · PeyronieOpen →14.02Testis & scrotum — non-neoplasticCryptorchidism · torsion · varicocele · hydrocele · orchitisOpen →14.03Testicular germ cell tumorsSeminoma vs nonseminomatous · markers · mixed tumorsOpen →14.04Testicular sex cord–stromal tumors & lymphomaLeydig · Sertoli · testicular lymphoma in older menOpen →14.05Prostate — benignBPH · acute vs chronic prostatitisOpen →14.06Prostate carcinomaZone · spread to bone · PSA · GleasonOpen →
15

Endocrine Pathology

11 pages
15.01Anterior pituitaryAdenomas by hormone · hypopituitarism · Sheehan · empty sellaOpen →15.02Posterior pituitary & water balanceCentral vs nephrogenic DI vs SIADHOpen →15.03HyperthyroidismGraves · toxic multinodular goiter · toxic adenoma · thyroid stormOpen →15.04Hypothyroidism & thyroiditisHashimoto · subacute granulomatous · painless · Riedel · congenitalOpen →15.05Thyroid neoplasmsPapillary · follicular · medullary · anaplastic · nodule workup logicOpen →15.06Parathyroid & calcium disordersPrimary/secondary/tertiary hyperparathyroidism · hypoparathyroidism · PTH-rPOpen →15.07Diabetes mellitusType 1 vs type 2 pathogenesis · DKA vs HHS · chronic complicationsOpen →15.08Adrenal cortex excessCushing syndrome causes & testing · hyperaldosteronismOpen →15.09Adrenal insufficiency & CAHAddison · Waterhouse-Friderichsen · 21-, 11β-, 17α-hydroxylase deficiencyOpen →15.10Adrenal medulla tumorsPheochromocytoma · neuroblastomaOpen →15.11MEN & hereditary endocrine syndromesMEN1, 2A, 2B · VHL · NF1 · Carney · McCune-Albright · APS-1/2 · islet tumor recapOpen →
16

Nervous System Pathology

14 pages
16.01Developmental CNS anomaliesNeural tube defects · Chiari I & II · Dandy-Walker · holoprosencephalyOpen →16.02Spinal cord lesionsPolio · SMA · ALS · ASA occlusion · tabes · SCD · syrinx · Brown-Séquard · cauda equinaOpen →16.03Brainstem & cortical lesion localizationMedial vs lateral brainstem syndromes · lobe lesions · aphasiasOpen →16.04StrokeIschemic types · vascular territories · hemorrhagic stroke · lacunesOpen →16.05Intracranial hemorrhageEpidural · subdural · subarachnoid · intraparenchymalOpen →16.06Raised ICP, herniation & hydrocephalusHerniation types & signs · communicating vs noncommunicating · NPHOpen →16.07CNS infectionsMeningitis CSF patterns · encephalitis · abscess · prion diseaseOpen →16.08Demyelinating disordersMultiple sclerosis · PML · osmotic demyelination · leukodystrophiesOpen →16.09DementiasAlzheimer · frontotemporal · Lewy body · vascular · Creutzfeldt-JakobOpen →16.10Movement disordersParkinson disease · Huntington disease · other basal ganglia lesionsOpen →16.11Adult brain tumorsGlioblastoma · meningioma · schwannoma · oligodendroglioma · pituitary · metastasesOpen →16.12Pediatric brain tumorsPilocytic astrocytoma · medulloblastoma · ependymoma · craniopharyngiomaOpen →16.13Neurocutaneous syndromesNF1 · NF2 · tuberous sclerosis · Sturge-Weber · von Hippel-LindauOpen →16.14Peripheral nerve & neuromuscular junctionGuillain-Barré · CIDP · myasthenia gravis · Lambert-EatonOpen →
17

Musculoskeletal Pathology

10 pages
17.01Skeletal development disordersAchondroplasia · osteogenesis imperfecta · osteopetrosisOpen →17.02Metabolic bone diseaseOsteoporosis · osteomalacia/rickets · Paget · lab comparison tableOpen →17.03Osteomyelitis & osteonecrosisOrganisms by host · avascular necrosis causesOpen →17.04Benign bone tumorsOsteochondroma · osteoid osteoma · osteoblastoma · giant cell tumor · enchondromaOpen →17.05Malignant bone tumorsOsteosarcoma · Ewing sarcoma · chondrosarcoma · metastasesOpen →17.06Osteoarthritis vs rheumatoid arthritisJoints · mechanism · imaging · labs · extra-articular featuresOpen →17.07Seronegative spondyloarthropathiesAnkylosing spondylitis · reactive · psoriatic · IBD-associatedOpen →17.08Crystal & infectious arthritisGout vs pseudogout crystals · septic arthritis · LymeOpen →17.09Muscle diseaseDuchenne vs Becker · myotonic dystrophy · inflammatory myopathiesOpen →17.10Soft tissue tumorsLipoma vs liposarcoma · rhabdomyosarcoma · desmoid · synovial sarcomaOpen →
18

Skin Pathology

7 pages
18.01Inflammatory dermatosesPsoriasis · lichen planus · eczema · seborrheic dermatitis · urticariaOpen →18.02Blistering diseasesPemphigus vulgaris vs bullous pemphigoid · dermatitis herpetiformis · EM, SJS/TENOpen →18.03Pigment disorders & neviVitiligo · albinism · melasma · nevus typesOpen →18.04MelanomaSubtypes · growth phases · prognosis by depth · risk factorsOpen →18.05Keratinocyte tumorsSeborrheic keratosis · actinic keratosis · SCC · basal cell carcinoma · keratoacanthomaOpen →18.06Skin infectionsImpetigo · cellulitis · necrotizing fasciitis · warts · molluscum · tineaOpen →18.07Skin signs of systemic diseaseAcanthosis nigricans · erythema nodosum · Leser-Trélat · xanthomasOpen →
PART IVFinal Rapid-Fire ReviewChapters 19 · 6 pages