Hematology Flashcards

Question

Hemostasis

Answer 1

1.) Vasoconstriction/ Vasospasm 2.) Platelet plug Requires von Willbrand Factor (vWF) produced by endothelial cells 3. ) Activation of clotting cascade: Formation of fibrin from fibrinogen, Intrinsic, Extrinsic & Final common pathway, Results in fibrin meshwork that stabilizes the plug 4. ) Blood clot formation 5.) Clot retraction 6.) Clot lysis- mediated by plasmin. plamin splits fibrinogen into Fibrin Degredation Product (FDPs), which dissolve the clot. If blood vessel injury is minor, platelet plugs may be sufficient to result in hemostasis w/o the clotting cascade

Answer 2

Platelet count 150,000- 400,000 Partial Thromboplastin Time (PTT) Measures activity of Intrinsic & Final common pathway Normal= 21-35 sec Prothrombin Time (PT) Measures activity of the Extrinsic and Final common pathways Normal= ~11-13 sec International Normalized Ratio (INR) Standardizes evaluation of extrinsic pathway Normal= 1.0

Answer 3

Plasma proteins Most are synthesized by liver von Willebrand factor made by endothelium Circulate as inactive procoagulation factors Calcium Required for clotting process

Answer 4

Ecchymosis Purpura- > 0.5 cm diameter Petechiae- < 0.5 cm diameter ``` Hemorrhage Epistaxis Hemoptysis Hematemesis Coffee Ground emesis Hematechezia Melena ```

Answer 5

Platelet count <100,000 <50,000= Bleeding potential <20,000= High risk for spontaneous bleeding Causes Decreased platelet production (bone marrow depression; HIV) Increased platelet destruction (immune or nonimmune) Disordered platelet distribution (pooling of platelets in spleen) Examples Immune Thrombocytopenia Purpura (ITP) – autoimmune Drug-induced thrombocytopenia Thrombotic Thrombocytopenia Purpura (TTP) –widespread platelet thrombi

Answer 6

Thrombocytopenia, Anemia (not enough platelets)

Answer 7

Necessary for the production of Prothrombin, Factors II, VII, IX, & X Fat soluble vitamin #1 source: green leafy vegetables Resident intestinal bacteria Causes Insufficient dietary intake Absence of bile salts necessary for Vit K Intestinal malabsorption syndromes Oral antibiotics that kill resident intestinal bacteria Neonates- immature liver & lack of normal intestinal flora

Answer 8

X-linked recessive, primarily affecting males Possibly a new mutation of factor VIII gene Mild, moderate, severe forms (<1% with severe forms) Avoid ASA, NSAIDS Factor VIII replacement Gene replacement therapy being studied

Answer 9

Deficiency of or defect in vWF Autosomal dominant or rarely—several autosomal recessive variants identified (severe manifestations d/t severely ↓vWF) Most cases mild Clinical manifestations of spontaneous bleeding w/ normal platelet count

Answer 10

Acquired coagulopathy in which clotting & hemorrhage occur within the vascular system Etiology Clinical conditions that activate clotting mechanisms (infection, hemorrhage, shock). Widespread clotting occurs → vessel occlusion, tissue ischemia Consumption of platelets and coagulation factors results Viscous cycle of clotting and bleeding results Treatment: Remove precipitating cause Restore balance between coagulation & fibrinolysis Maintain organ viability

Answer 11

Leukopenia Neutropenia (agranulocytosis) Aplastic anemia Infectious mononucleosis

Answer 12

Neoplasms arising here (bone marrow) cause leukemias or plasma cell dyscrasias Neoplasms arising here (lymph nodes) are lymphomas

Answer 13

Malignant neoplasms of hematopoietic stem cells In bone marrow Create abnormal white blood cells Lymphocytic immature lymphocytes originating in bone marrow, infiltrating spleen, lymph nodes, CNS, and other tissues Myelogenous Involve myeloid pluripotent stem cells in bone marrow, interfering w/ maturation of all blood cells (granulocytes, erythrocytes, thrombocytes).

Answer 14

Mutation of myeloid cell line Overproduction of abnormal monocytes or granulocytes Production of other cell types decreases

Answer 15

Mutation of lymphoid cell line Overproduction of abnormal immune cells Production of other cell types decreases

Answer 16

Definition- malignant neoplasms of the hematopoietic stem cells Types: Acute ALL AML Chronic CLL CML

Answer 17

More common Random, non-contiguous spread B cell T cell

Answer 18

Malignancy of lymphoid tissue Begins in a single lymph node then spreads contiguously Characterized by presence of Reed-Sternberg cell (B cell origin)

Answer 19

Abnormal B cells proliferation Excessive production of monoclonal antibody Can form tumors in bones & soft tissue Produce abnormal antibodies M protein or Bence Jones protein…toxic to renal tubules Immune depression due to decreased levels of normal immunoglobulins Proteins increase blood viscosity. Proteins may break into amyloid & cause heart failure and neuphropathy. Proliferation and activation of osteoclasts Osteolytic bone lesions- breakdown of bone…hypercalcemia Compression fractures

Answer 20

Lymphoma, Thrombocytopenia, Anemia, Potassium is now floating extracellularly