Chronic Leukemias, Thrombocytopenia

What is chronic leukemia?

The slow growth of mature (differentiated) cells which do not function normally

What is the onset and survival time of chronic leukemia?

Onset is gradual, survival time is longer than acute

What are the two types of chronic leukemia?

1. Chronic lymphocytic leukemia (CLL)

2. Chronic myelogenous leukemia (CLM)

Which type of cell does Chronic lymphocytic leukemia affect?

CLL primarily affects B cells

What happens to the B cells in CLL?

The B cells refuse apoptosis commands and accumulate while being inactive, leading to no antibody production

What three cytopenias does CLL cause?

CLL causes anemia, thrombocytopenia, and neutropenia

What type of cell does Chronic myelogenous leukemia affect and what does it lead to?

CML affects stem cells, leading to excessive amounts of marrow granulocytes, RBC precursors, and megakaryocytes

What are the three phases of CML?

1. Chronic (lasts 2-5 yrs): may be asymptomatic

2. Accelerated: (lasts 6-18 months): primary symptoms develop, with more immature cells in the bone marrow and blood

3. Terminal blast phase (lasts 3-6 months): blast cells proliferate with symptoms becoming more severe

   1. Resembles AML

What chromosome is observed in 95% of CML cases?

The Philadelphia chromosome is observed in 95% of CML cases

How is Philadelphia chromosome made?

Chromosomes 22 and 9 exchange long ends, with the smaller 22 being known as Philadelphia chromosome

How are chronic leukemias evaluated?

Chronic leukemias are evaluated through blood tests and bone marrow biopsy

Treatments for Chronic Leukemias

• Bone marrow transplant

• Biological response modifiers: increases body’s immune response

  • Ex: interferon alpha

• Combination chemotherapy

What is CLL’s survival rate?

CLL’s survival rate is highly variable

What is CML’s survival rate?

CML’s survival rate is 90%

What is death usually caused by in chronic leukemias?

Death is usually caused by infection or hemorrhage due to metastatic infiltration of tissues

What is thrombocytopenia?

Thrombocytopenia is when there is a low number of platelets

What are the dangers of thrombocytopenia?

Risk of hemorrhage can occur with minor trauma

Spontaneous bleeding can occur without any trauma (petechiae, purpura)

What is Heparin-induced thrombocytopenia (HIT)?

HIT is when the immune system reacts to heparin (anticoagulant) and platelet factor 4, causing platelets to clot together and form dangerous blood clots while lowering the platelet count

What is Immune thrombocytopenic purpura (ITP)?

ITP is when the immune system attacks the body’s own platelets. Antibodies attach and mark platelets for destruction for immune cells in the spleen.

What is Thrombocythemia?

Thrombocythemia is when there is a high number of platelets

What is thrombopoietin’s function?

Thrombopoietin’s function is to stimulate platelet production

What is primary thrombocythemia?

Primary thrombocythemia

• Platelet production increases due to defects in thrombopoietin receptors on the platelets

• The thrombopoietin receptor can’t bind and remove thrombopoietin from the blood, resulting in more platelet production

What is Secondary thrombocythemia?

Secondary thrombocythemia

• Occurs by any disease that stimulates thrombopoietin production

What are people with thrombocythemia at high risk of?

High risk of large-vessel thrombosis