Heme Onc Flashcards
Lead poisoning
Affecting ferrochelatase and ALA dehydrase
(Heme synthesis starts w glycine and succinylCoA w cofactors B6 and delta ALA synthase)
Leads to accumulation of protoporphyrin and delta ALA
Cause microcytic anemia due to lack of heme
Also
Paroxysmal nocturnal hemoglobinuriA
Increased complement mediated RBC lysis due to impaired GPI anchor that protects RBC from complement
Located on X chromosome so only one copy of gene is active at a time
acquired mutation in hematopoietic stem cell leads to hemolysis
Hemophilia
Deficiency in intrinsic pathway
A: VIII, B: IX
Increases PTT
Vitamin K deficiency (warfin)
General coagulation defect
Decreases synthesis of 1972 C and S
Increased PTT and PT
Bernard Soulier syndrome
Defect in platelet plug formation
Decreased GpIb leading to defect in platelet vWF adhesion
Increased bleeding time, decreased platelet count
Glanzamann thrombasthenia
Defect in platelet plug formation
Decreased GpIIb/IIIa leading to decreased platelet to platelet aggregation
Increased bleeding time
Immune thrombocytopenia
Anti GpIIb/IIIa antibodies leading to macrophage destruction of platelet antibody complex
Decreased platelet survival
Thrombotic thrombocytopenia
Inhibition or deficiency of ADAMTS 13 leading to decreased degradation of vWF and unnecessary platelet aggregation and thrombosis
Decreased platelet survival time
Von Willebrand disease
Intrinsic pathway coagulation defect
Decreased vWF leading to decreased factor VIII and decreased platelet plug formation
Normal PT and increased PTT
Treat w DDAVP (desmopressin, releasing vWF from endothelium)
DIC
Widespread activation of clotting leading to deficiency in clotting factors
Caused by sepsis, trauma, malignancy, transfusion
Increased bleeding time, PT, PTT, decreased platelet count
Factor V Leiden
Production of mutant factor V that is resistant to degradation by activation of protein C
Most common cause of hypercoaguability
Hodgkin lymphoma
Localized single group of nodes, extra nodal rare
Contiguous spread
Constitutional B symptoms: low grade fever, night sweats, weight loss
Good prognosis
50 percent cases associated w EBV
Young adults and greater than 55
Non-Hodgkin lymphoma
Multiple peripheral nodes w extra nodal involvement common
Noncontiguous spread
Fewer constitutional symptoms
Peak incidence 20-40
May be associated w HIV and immunosuppression
Reed Steenberg cell
Tumor giant cell seen in Hodgkin lymphoma
Binucleated or bilobed w halves as mirror images (owl eye)
Better prognosis w strong stromal or lymphocytic reaction against RS cells
Burkett lymphoma
T(8;14) translocation of c-myc
Starry sky appearance
Associated with EBV