Ch 14 Key Concepts Flashcards Preview

SBL Exam 1 > Ch 14 Key Concepts > Flashcards

Flashcards in Ch 14 Key Concepts Deck (17)
Loading flashcards...

caused by deficiencies of folate of vit B12 that lead to inadequate synthesis of thymidine and defective DNA replication

megaloblastic anemia
- results in enlarged abnormal hematopoietic precursors, ineffective hematopoiesis, macrocytic anemia, and pancytopenia


what is vit B12 deficiency also associated with?

neurologic damage
- particularly in the posterior and lateral tracts of the spinal cord


caused by chronic bleeding or inadequate iron intake

iron deficiency anemia
- results in insufficient hemoglobin synthesis and hypochromic, microcytic red cells


caused by inflammatory cytokines, which increase hepcidin levels and thereby sequester iron in macrophages
- also suppress erythropoietin production

anemia of chronic disease


caused by bone marrow failure (hypocellularity) due to diverse causes, including exposures to toxins and radiation, idiosyncratic reactions to drugs and viruses, and inherited defects in telomerase and DNA repair

aplastic anemia


what are the two forms of pure red cell aplasia?

1. acute: parvovirus B19 infection
2. chronic: associated with thymoma, large granular lymphocytic leukemia, presence of neutralizing antibodies against erythropoietin, and other autoimmune phonemona


what are the other causes of underproduction anemias?

marrow replacement (tumors, granulomatous disease; so-called myelophthisic anemias), renal failure, endocrine disorders, liver failure


caused by autoantibodies against platelet antigens
- may be triggered by drugs, infections, lymphomas, or may be idiopathic

immune thrombocytopenia purpura


what two disorders manifest with:
- thrombocytopenia, microangiopathic hemolytic anemia, and renal failure

thrombotic thrombocytopenic purpura and hemolytic uremic syndrome


caused by acquired or inherited deficiencies of ADAMTS 13, a plasma metalloprotease that cleaves very-high molecular weight multimers of vWF

- fever and CNS involvement common


what does deficiency of ADAMTS13 result in?

abnormally large vWF multimers that activate platelets


caused by deficiencies of complement regulatory proteins or agents that damage endothelial cells, such as Shiga-like toxin elaborated by E.coli strain O157:H7

- the abnormalities initiate platelet activation, platelet aggregation, and microvascular thrombosis


AD disorder caused by mutations in vWF, a large protein that promotes the adhesion of platelets to subendothelial collagen
- typically causes a mild to moderate bleeding disorder resembling that associated with thrombocytopenia

Von Willebrand disease


X-linked disorder caused by mutations in factor 8
- affected males typically present with severe bleeding into soft tissues and joints have a PTT

hemophilia A


X-linked disorder caused by mutations in coagulation factor 9
- clinically identical to hemophilia A

hemophilia B


syndrome in which systemic activation of the coagulation leads to consumption of coagulation factors and platelets
- can produce bleeding, vascular occlusion, or tissue hypoxemia

disseminated intravascular coagulation


what are the common triggers of disseminated intravascular coagulation?

sepsis, major trauma, certain cancers, obstetric complications