Adequacy of extrinsic and common coagulation pathways

Time needed for plasma to clot in presence of exogenous tissue thromboplastin and Ca2+

Intrinsic and common clotting pathways

Time needed for plasma to clot in presnence of kaolin (activates factor 12)

Release of tissue factor or thromboplastic substances into circulation

Activation of Factor 12 or surface contact, collagen, or neg. charged sub.

Idiopathic (ITP)

Chronic Primary ITP: Anitplatelet Ig (Gp IIb/ IIIa or Ib/IX complexes)

Chromic Primary ITP: Bone marry has increased # of megakaryocytes

Diagnosis: exclusion of secondary ITP

Clinical findings: petechiae (bruising), epistaxis (gum bleeding), and hemorrhages

Clinic: 3-5% treated w/ unfractioned heparin

IgG antibodies that bind factor 4, heparin dependant

Cessation of heparin therapy breaks the cycle

Pentad- renal failiure

ADAMTS13 degrades vWF

Patient deficient in metalloprotease (ADMTS13)

Dominance of renal failure and no neurological symptoms (childhood)

ADAMTS13 levels normal

X-linked Recessive: Hemophillia A (Factor VIII)- Classic

X-linked: Hemophillia B (Factor IX)- Christmas

Autosomal: Von Willebrand Disease

deficiency in clotting factors- more common

Vit. K essential for factors 7, 9, 10

Epithelial cell neoplasia

T cells (thymocytes) neoplastic

Malignant- Type I: cytologically benign, biologically aggressive

Malignant-Type II: thymic carcinoma