Hematology Disorders Flashcards
Leukopenia
Decrease in total number of leukocytes in the blood, most often affecting neutrophils
Agranulocytosis
absence of neutrophils
Aplastic anemia
All myeloid stem cells are affected, resulting in thrombocytopenia, agranulocytosis, and anemia.
Lab value for neutropenia
- commonly defined as a circulating neutrophil count of less than 1500/μL
- mild (1000 to 1500/μL)
- moderate (500 to 1000/μL)
- severe (<500/μL)
Cyclic neutropenia
autosomal dominant neutropenia begining in infancy, which occurs every ~21 days and lasts for 2-3 days
Kostmann Syndrome
Severe congenital neutropenia
What can cause acquired neutropenia?
- Cancer
- autoimmune disorders
- Infection related
- Felty Syndrome
- Radiation to bones
- Drug related (depresses bone marrow function)
- Splenomegaly (neutrophils get trapped in the spleen)
What is Felty Syndrome?
A type of rhematoid arthritis in which neutrophils gets destroyed in the spleen
Common symptoms of neutropenia
- Skin infections and ulcerative necrotizing lesions of the mouth
- Respiratory tract infections
- Pus is absent from infections because pus consists of tissue, WBCs, and pathogens that are liquified by neutrophil enzymes
Infectious mononucleosis
self-limiting lymphoproliferative disorder caused by the Epstein-Barr virus (EBV), a member of the herpesvirus family
Pathogenesis of mononucleosis
- Spreads to oropharyngeal lymphoid tissue and to B lymphocytes, which have receptors for EBV
- Infection may kill infected B cell, or virus may incorporate itself into the cell’s genome. The B cells with the EBV genome proliferate and produce heterophil antibodies (diagnostic test).
- normal immune response is important in controlling proliferation of EBV-infected B cells with cytotoxic T cells and NK.
- virus remains in a few transformed B cells in the oropharyn- geal region and is shed in the saliva. Once infected with the virus, asymptomatically infected for life
Incubation period for mononucleosis
4-8 weeks
Most common leukemia among children
Acute Lymphocytic Leukemia
Most common leukemias among adults
Chronic Lymphocytic Leukemia
Acute Myeloid Leukemia
Risk factor for leukemia
- Radiation
- Chemical exposure (formaldehyde and benzene)
- Chemotherapy
- Family hx
- Down syndrome
Translocation involved in CML
Philadelphia chromosome: translocation between long arms of c22 and c9.
Sign and symptoms of AML and ALL
- Sudden onset
- Night sweats
- Anemia
- Fever
- Bone pain
- Bleeding and bruising
- Potential CNS involvement: headaches, nausea, palsies
Long term survival for adults with ALL or AML
30-40%
Age group for CLL and CML
Primarily older with average age 72 yrs (CLL) and 67 yrs (CML) at diagnosis
Hodgkin Lymphoma
cancers characterized by Reed-Sternberg cells that begins as a malignancy in a single lymph node and then spreads to contiguous lymph nodes
Non Hodgkin Lymphoma
originate in the lymph nodes, are multicentric in origin
and spread early to various lymphoid tissues throughout the body, especially the liver, spleen, and bone marrow
Signs and symptoms of CML and CLL
Multiple myeloma
B cell malignancy of terminally differentiated plasma cells involving bone and bone marrow
Why are people with multiple myeloma at risk for fractures and hypercalcemia?
It involves proliferation of osteoclasts, causing increased bone resorption and destruction
What is hemostasis?
multistep physiological process that preserves vascular integrity by balancing the processes that maintain blood
in a fluid state and **prevent excessive bleeding **following injury
What disorders would be associated with increased platelet numbers?
Reactive disorder (iron-deficiency anemia, splenectomy, cancer, chronic inflammatory conditions)
Myeloproliferative disorders (polycythemia vera)
Lab value of thrombocytosis
elevations in the platelet count above 1,000,000/μL
How do atherosclerotic plaques increase platelet function?
Atherosclerotic plaques disturb blood flow, causing endothelial damage and promoting platelet adherence.
Platelets adhere to the vessel wall, release growth factors, and cause proliferation of smooth muscle to contribute to the development of atherosclerosis
What does thrombus formation result from?
Primary (genetic) or secondary (acquired) disorders that affect the coagulation components of the blood clotting cascade
Common inherited factors causing hypercoagulability
Mutation in the factor V gene (factor V Leiden)
Mutation in the prothrombin gene
What population is at risk for mutation in factor V gene?
- Carried by 2-5% of white people
- Mutation found in majority of people who have recurrent DVTs
- One of the most common causes of primary and recurrent thromboembolism in pregnancy
- associated with abruptio placentae (premature placental separation) and fetal growth disturbance
What are conditions associated with acquired hypercoagulability?
Prolonged bed rest or immobility
Oral contraceptive agents and pregnancy
Myocardial infarction
Heart failure
Malignant diseases
Antiphospholipid antibody syndrome
What is antiphospholipid syndrome?
- autoantibodies directed against several negatively charged phospholipids, causing an increase in coagulation activity (mechanism unclear)
- causes recurrent thrombosis, repeated fetal loss, and thrombocytopenia
- seen with lupus
What types of conditions are associated with arterial thrombi?
conditions that produce an increase in platelet numbers or turbulence in blood flow with platelet adhesion
What conditions are associated with venous thrombi?
inherited or acquired conditions that cause a decrease in anticoagulation factors or
produce a stasis of blood, thereby causing an increase in procoagulation factors
How does smoking cause thrombi?
increases sensitivity of platelets to factors that promote adhesiveness and aggregation
Lab value of thrombocytopenia
decrease in the number of circulating platelets to a level less than 100,000/ μL
Causes of thrombocytopenia
decreased platelet production
decreased platelet survival
splenic sequestration
dilution
What conditions reduce platelet production?
- leukemia
- radiation and chemotherapy
- anemia
What causes reduced platelet survival
antiplatelet antibodies directed against platelet self-antigens or against antigens formed on platelets after blood transfusion or pregnancy
acute disseminated intravascular clotting or thrombotic thrombocytopenic purpura (TTP): platelets get used up with excessive clotting and leads to a deficiency.
What is dilutional thrombocytopenia?
Massive blood or plasma transfusions may cause a dilutional thrombocytopenia because blood stored for more than 24 hours has no viable platelets
