Histochemical stainsPrussian blue – iron Congo red – amyloid Acid fast (Ziel-Neelsen, Fite) – acid-fast bacilli Periodic acid Schiff (PAS) – high carbohydrate content molecules Trichrome – cells and connective ...
Antibody stainsCytokeratin – epithelial cells Vimentin – cells of mesenchymal origin except the 3 muscle types; stains many sarcomas Desmin – smooth, cardiac, and skeletal myosin
Hematoxylin and EosinHematoxylin: Stains blue to purple- Nucleus and nucleolus- Calcium- Bacteria Eosin: Stains pink to red- Cytoplasm- Collagen- Fibrin- RBCs- Thyroid colloid
Contents of platelet granulesAlpha granules:- Fibrinogen- Fibronectin- Factor V and vWF- Platelet factor 4- PDGR Dense bodies:- ADP- Ca2+- Histamine and serotonine- Epinephrin
Immune thrombocytopenia purpura (ITP)Immune-mediated attack (usually IgG antiplatelet antibodies) against platelets leading to decreased platelets (thrombocytopenia) which result in petechiae, purpura (bruises), and a bleeding diathesis ...
Thrombotic thrombocytopenic purpura (TTP)Rare disorder of hemostasis in which there is a widespread intravascular formation of fibrin-platelet thrombi. It is sometimes associated with an acquired or inherited deficiency of the enzyme ADAMTS13, ...
Hemolytic uremic syndrome (HUS)Thrombotic microangiopathy due to endothelial cell damage. - Occurs mostly in children, typically after a gastroenteritis (typically due to Shiga toxin-producing E coli 0157:H7) - Abdominal pain, diarhhea- ...
Coagulation factorsThe intrinsic pathway is activated by the contact factors, which include:- Subendothelial collagen- High molecular weight kininogen (HMWK)- KallikreinXII → XIIa The extrinsic pathway is activated by ...
Coagulation lab testsProthrombin time (PT): Tests extrinsic and common coagulation pathways- VII, X, V, prothrombin, fibrinogen- INR standardizes the PT Partial thromboplastin time (PTT): Tests instrinsic and common coagulation ...
Thrombus vs blood clotThrombus- Location: Intravascular- Composition: Platelets, fibrin, RBCs and WBCs- Lines of Zahn: Present- Shape: Has shape Blood clot- Location: Extravascular or intravascular (postmortem)- Composition: ...
Major causes of shockCardiogenic shock (pump failure): myocardial infarction, cardiac arrhythmias, pulmonary embolism, cardiac tamponade Hypovolemic shock (reduced blood volume): hemorrhage, fluid loss secondary to severe ...
Mönkeberg medial calcific sclerosisMedial calcification of medium-sized (muscular) arteries, such as femoral, tibial, radial, and ulnar arteries. - Asymptomatic, but may be detected by x-ray.
Arteriolosclerosis- Affects small arteries and arterioles. - Hyaline arteriolosclerosis: pink, glassy arterial wall thickening with luminal narrowing seen in benign hypertension, diabetes, and aging- Hyperplastic arteriolosclerosis: ...
Syphilitic aneurysmsInvolve the ascending aorta in tertiary syphilis. Syphilitic aortitis causes an obliterative endarteritis of the vasa vasorum, leading to ischemia and smooth-muscle atrophy of the aortic media. Syphilitic ...
Vascular ectasiasNevus flammeus nuchae: Neck "birthmark" or "stork bite" that regresses. Port wine stain: Vascular birthmark that does not regress. Spider telangiectasias: Occur on the face, blanch with pressure, and ...
Glomus tumorBenign, small, painful tumor of the glomus body that usually occurs under fingernails.