White Blood Cell Disorders Flashcards
Signs + symptoms of infectious mononucleosis.
- fever
- sore throat
- pharyngitis
- generalized lymphadenopathy
- hepatosplenomegaly
- (antibody + T cell response)
Cause of infectious mononucleosis?
-Typically EBV
can also be CMV.
Serologically: EBV –> heterophile positive
CMV heterophile negative
What does mono mainly infect in the body, and then how does our body respond?
- oral mucosa –> Pharyngitis
- liver –> elevating liver enzymes, causing hepatomegaly
- B cells
Response: - Cytotoxic T cells (increase) cause T cell hyperplasia in lymph causing general lymphadenopathy
- T cell hyperplasia in PALS causing splenomegaly
- high WBC count with atypical lymphocytes n the blood
How can you distinguish Hodgkins and non-hodgkins histologically?
Hodgkins –> Reed-sternberg giant cells (neoplastic cells)
What are the 3 main neoplastic proliferations of white blood cells?
1) Lymphoid neoplasms
2) Myeloid neoplasms
3) Histiocytic
What are the 3 main groups of myeloid neoplasms?
1) Acute myelogenous leukaemia
2) Chronic myeloproliferative disorders
3) Myelodysplastic syndromes
Explain pathophysiology of acute myeloid leukaemia?
Genetic mutation causing a “maturation block” that interferes with the differentiation of early myeloid cells, thus leads to accumulation of myeloid blast cells in the bone marrow.
How can acute promyelocytic leukaemia be distinguished from acute monocytic and acute megakaryoblastic leukaemia?
Acute promyelocytic leukaemia has myeloperoxidase (MPO) in it’s cytoplasm.
How is acute promyelocytic leukemia treated?
All-trans-retinoic acid (ATRA) is given. It binds to altered receptors causing myeloblasts to mature, and eventually die (lifespan 6 hrs), clearing the tumour quite quickly.
How are lymphoblasts differentiated from myeloblasts and mature lymphocytes?
Lymphoblasts have a positive nuclear stain for TdT (DNA polymerase)
What type of cells are involved in chronic lymphocytic leukemia (CLL)?
Neoplastic proliferation of naive B cells.
Complications of CLL:
- hypogammaglobulinemia –> infections
- autoimmune hemolytic anemia
- transformation to diffuse large B-cell lymphoma (Richter transformation)
What is the Richter transformation? Which disease states can it occur in?
The transformation to diffuse large B-cell lymphoma.
Can occur in:
- CLL (chronic lymphoid leukemia)
- hairy cell leukaemia
What type of cell(s) are involved in hairy cell leukaemia?
Neoplastic proliferation of mature B cells
What type of leukaemia is the most common in adults?
CLL (chronic lymphocytic leukemia)
In what leukemia do you find “dry tap” from the bone marrow aspiration?
- Hairy cell leukemia
- myelofibrosis
Due to marrow fibrosis.
What do you clinically find in hairy cell leukaemia?
- massive splenomegaly
- pancytopenia
- dry tap in marrow aspiration
- NO lympadenopathy!! (vs CLL, where there is)
- (+) For TRAP (tartrate resistant acid phosphatase)
What are Pautrier microbabscesses? What condition do you find them in?
They are little aggregations of neoplastic cells in the epidermis.
Found in mycosis fungoides (leukaemia)
What can mycosis fungoides progress to?
Sezary syndrome (T cell leukaemia)
What are cells (+) for in hairy cell leukaemia?
TRAP
What does TRAP (+) indicate?
Hairy cell leukaemia
What is the leukamoid reaction?
Increase in WBCs due to infection.
Looks like it mimics CML
How can you distinguish CML and leukamoid reaction?
CML is:
- negative for LAP stain
- high basophils
- presence of t(9;22), the Philadelphia chromosome
How do you treat CML?
Tyrosine kinase inhibitor
imatinab
What does CML present with? What can it progress to?
- Massive splenomegaly
- Increased WBCs, mainly basophils
Can progress to:
- AML (2/3s of cases)
- ALL (1/3)
What is polycythemia?
What is absolute and relative polycythemia?
Polycythemia is disease state with high hematocrit.
Absolute polycythemia = increase in RBCs causing the increase in Ht
Relative polycythemia = decrease in volume of plasma
What is polycythemia vera?
Neoplastic proliferation of mature myeloid cells, with high RBCs mainly, but also high granulocytes and platelets.
Signs + symptoms for polycythemia vera?
- headache + blurry vision
- flushed skin/face (high RBC)
- risk of venous THROMBOSIS!! (hepatic v., portal v., dural sinus)
- itching (after bath from high mast cells)
Treatment for polycythemia vera?
- phlebotomy
- hydroxyurea
What is hydroxurea used to treat?
- sickle cell anemia
- polycythemia vera (PV)
- CML
- cervical cancer
What type of mutation is present in polycythemia vera?
JAK-2 kinase mutation
Explain EPO production in reactive polycythemia
High EPO from ectopic production. Due to renal cell carcinoma
What is myelofibrosis?
Neoplastic proliferation of mature myeloid cells, especially megakaryocytes.
They overproduce PDGF (platelet derived growth factor) and cause marrow fibrosis.
Clinical/histo signs of myelofibrosis?
- splenomegaly
- tear drop RBCs
- nucleated RBCs
- immature granulocytes
What condition do you find tear drop RBCs?
Myelofibrosis
