Ch 20: WBCs Flashcards
Neutrophil count that defines neutropenia? (List ranges for mild, moderate, and severe)
Mild: 1000-1500/ µL Moderate: 500-1000/ µL Severe: <500/ µL
What are the general principles that lead to neutropenia?
Decreased production, ineffective production, or increased destruction
List some causes of decreased production of neutrophils
Irradiation, drug induced, viral infection, congenital (Kostmann syndrome or infantile genetic agranulocytosis), cyclic
List causes of ineffective production of neutrophils
Megaloblastic anemia, myelodysplastic syndromes
List causes of increased destruction of neutrophils
isoimmune neonatal, autoimmune, idiopathic, drug induced, Felty syndrome, SLE, dialysis, splenic sequestration, increased margination **BIG PICTURE: 1) too much consumption, like in infection 2) too much sequestration, like in hypersplenism 3) too much Ab destruction
Neutrophil count that defines neutrophilia?
Above 7000/ µL
Causes of neutrophilia?
1) increased mobilization from bone marrow 2) enhanced release from marginal pool 3) stimulation of granulopoiesis
Huge elevation of WBCs, usually in response to acute infections or severe hemorrhage. May be mistaken for leukemia, esp CML. Distinguished by segmented neutrophils, high leukocyte alkaline phosphatase activity, and blue cytoplasmic inclusions (Dohle bodies).
LEUKEMOID REACTION
Seen in response to allergic reactions, parasitic infections, or persistent Ag-Ab complexes. Leads to necrosis, especially of myocardium and nervous system.
Eosinophilia - remember major basic protein causes the cell injury!
Commonly observed in immediate-type hypersensitivity reactions and chronic myeloproliferative neoplasms. Think histamine, chondroitin sulfate, leukotrienes.
Basophilia
Often occurs in neutropenic states as a compensatory mechanism
Monocytosis
Myeloproliferative neoplasm, derived from abnormal pluripotent stem cell, strong association with Philadelphia chromosome, BCR/ABL, t(9;22)
Chronic Myelogenous Leukemia
Phase of CML associated with lower blasts, normal platelets, hypercellularity in BM, and clusters of megakaryocytes.
Chronic phase
Phase of CML associated with increasing WBC count, increasing splenomegaly, persistent thrombocytopenia, and 10-20% blasts
Accelerated phase
Phase of CML associated with at least 20% blasts, extramedullary proliferation of blasts, clusters of blasts (hint: ___ from the past)
Blast phase
Myeloproliferative neoplasm from clonal hematopoietic stem cell that leads to autonomous production of RBCs not regulated by EPO. Associated with JAK2 mutation. Hyperplasia of all hematopoietic elements.
Polycythemia Vera
List the 3 stages of PV, and the erythropoietic pattern for each
1) Prepolycythemic - erythroid precursors abundant, maturation of cells normal 2) Polycythemic - erythroid precursors abundant, maturation of cells normal 3) Postpolycythemic - erythropoiesis ceases and there is an increase in extramedullary hematopoiesis (spleen!). Despite this EMH, stage characterized by anemia.
So PV is an unregulated increase of RBC production. How high can the lab values actually go?
Hemoglobin can exceed 20 g/dL. Hematocrit surpasses 60%. Whoa. This implies all kinds of circulation difficulties including angina pectoris, claudication, GI ulcers, thrombosis (stroke, MI)
Myeloproliferative neoplasm characterized by megakaryopoiesis, granulopoiesis, and marrow fibrosis
Primary myelofibrosis
Stage of primary myelofibrosis presenting with thrombocytosis, hypercellular bone marrow, and megakaryocytes with atypical “cloud-like” nuclei
Prefibrotic (early stage)
Stage of primary myelofibrosis presenting with tear drop RBCs, a characteristic reticulin or collagen fibrosis in the marrow, and extramedullary hematopoiesis
Fibrotic (late stage)
Myeloproliferative neoplasm associated with JAK2 mutation or MPL mutation. Peak incidence ~70yo. In rare cases, can transform to AML.
Primary myelofibrosis
What do the megakaryocytes distinctly look like in essential thrombocytopenia?
Stag-horn-shaped
Uncontrolled proliferation of megakaryocytes, accompanied by recurrent episodes of thrombosis and hemorrhage?
Essential thrombocytopenia
