CLL Flashcards
What is CLL and how does it arise?
o Increased clonal proliferation of small mature B cells.
o No clear cause but has been found to be linked with epigenetic changes including trisomy 21 and 17p deletion.
What are the symptoms and their explanations?
o Lethargy, pallor, and fatigue/anaemia – this is due to the over-proliferation of lymphoid blasts, causing myelosuppression and inhibiting erythropoiesis.
o Recurrent infections – this is due to the over-proliferation of immature lymphocytes, meaning there are not enough functioning lymphocytes to fight infections. These blasts also overcrowd the bone marrow meaning they negatively impact normal leucopoiesis, reducing numbers of other WBCs. Hypogammaglobulinemia (not enough IgG) and immune dysfunction is seen.
o Bruising – this is due to the over-proliferation of lymphoid blasts overcrowding the bone marrow and negatively impacting thrombopoiesis. This decreases the number of platelets, which means that blood doesn’t clot properly and minor injuries to capillaries do not clot properly so bruise easily instead.
o Splenomegaly – this is due to many immature lymphocytes being trapped in the reticuloendothelial system and the spleen, causing enlargement.
o Lymphadenopathy – this is due to overcrowding of immature lymphoid cells in the bone marrow, causing enlarged lymph nodes where these cells reside.
What are the laboratory findings?
o Normochromic, normocytic anaemia – low RBC count and Hb.
o Hyperleukocytosis – increased number of WBCs.
o Thrombocytopenia – decreased number of platelets.
o Lymphocytosis – increased number of lymphocytes.
o High number of monocytes.
o Reduced Igs.
o Blood film shows small lymphocytes and smudge cells.
o Bone marrow trephine shows small cells with scanty cytoplasm and condensed nuclear chromatin.
What further tests can be done?
o Immunophenotyping – looks for presence of certain markers like CD19 and CD20.
o Biochemistry tests – Igs to look for hypogammaglobulinemia.
o Cytogenetics – looks for genetic abnormalities and markers such as ZAP-70, a protein kinase in signalling.
o DAT – looks for the presence of autoantibodies against erythrocytes as autoimmune haemolysis can occur in CLL.
How is CLL treated?
o Rituximab and chemotherapy – started when symptoms are significant.
o Corticosteroids – aids in recovery from pancytopenia (low blood cells).
o Splenectomy – reduces pain due to splenomegaly which doesn’t respond to steroid treatment.
o Immunoglobulin replacement – replaces IgGs which are low in these patients – well tolerated and improves quality of life.
