Quantitative WBC Abnormalities Flashcards
Normal WBC count
4.5-11.5 x 10^9/L
Definition of leukocytosis
Any WBC count over 11.5 x 10^9/L
3 general mechanisms for all types of leukocytosis
- Cells from BM (increased flow from BM)
- Shift of cells from marginal granulocyte pool to circulating granulocyte pool
- Decreased outflow of cells from blood
5 physiological causes of leukocytosis
- Exercise
- Stress
- Hypoxia
- Labor
- Shfit from marginal pool to circulating pool?
6 pathological causes of leukocytosis
- Disease or tissue damage
- Infection
- Toxins (drugs, chemicals)
- Necross (MI, burns surgery)
- Hemorrhage
- Hemolysis
Definition of leukemoid reaction
Excessive leukocytosis
- WBC > 50.0 x 10^9/L WITH a left shift
- Shift to the left in myeloid series (immature cells in PB)
2 types of leukemoid reactions
- Neutrophilic
- Lymphocytic
Production of bands, myelos, metas - sometimes difficult to differentiate from chronic myelogenous leukemia and occurs with infections, hemolysis, and burns
Neutrophilic leukemoid reaction
Produces lymphs- maybe be hard to distinguish from Chronic Lymphocytic Leukemia and these reactions can occur in Pertussis, mononucleosis, and viral infeactions
Lymphocytic leukemoid reaction
CML vs. leukemoid reaction
- Incrase in what cells?
- CML: increases in all granulocytes including eosinophils and basophilis
- Leukemoid: increase in granulocytes BUT it is uncommon for increases in eosinophils and basophils
CML vs. leukemoid reaction
- Dyspoietic morphology (mixed granulation)
- CML: dyspoietic morphology
- Leukemoid: no dyspoietic morphology
CML vs. leukemeoid reaction
- Platelets
- CML: giant and hypogranular platelets
- Leukemoid: Normal platelet morphology
Define leukoerythroblastosis
Presence of both immature neutrophils and nucleated RBCs in the PB
Cause of leukoerythroblastosis
Caused by a space occupying lesion in the bone marrow (fibrosis, metastic tumor, lymphoma, leukemia)
Define leukopenia
Any WBC count < 4.5 x 10^9/L
Mechanisms of leukopenia
- Decreased flow of cells from bone marrow
- Shift from CGP to MGP
- Increased outflow from blood
Causes of leukopenia
- Viral infections
- Drugs (some antibiotics, chemotherapy)
- Radiation
- Hematologic disorders (pernicious anemia, aplastic anemia, MDS)
What is a relative value?
% of cell type in specified volume
What is an absolute value?
of cell type in specified volume
Calculation for the absolute value
Absolute = total WBC x % cell type (add up segs and bands for neutrophil count)
Definition of neutrophilia
Increase in neutrophils > 8.1 x 10^9/L
Causes of neutrophilia
- Physiologic: stress, exercise, pregnancy
- Acute infection, usually bacterial
- Chronic inflammation (gout, RA, burns)
- Steroids (cause demarginalization and inhibit neutrophil apoptosis)
Define neutropenia
Decrease in neutrophils < 2.3 x 10^9/L
Neutropenia mechanisms
- Decreased BM production
- Shift from CGP to MGP
- Increase in rate of outflow of neutrophils from blood
Neutropenia severity
- Severe w/ increased risk of infection
< 1.5 x 10^9/L
Neutropenia severity
- Increased risk of auto-infection
< 1.0 x 10^9/L
Neutropenia severity
- Very serious risk, reverse isolation and/or prophylactic antibiotics
< 0.5 x 10^9/L
Definition of eosinophilia
Increase in eosinophils > 0.6 x 10^9/L
Causes of eosinophilia
- Allergic responses
- Skin disorders
- Parasitic infections, especially helminths (worms)
- Infectious disease
- Hematologic disorders
Definition of eosinopenia
Decrease in eosinophils; usually not significant and is difficult to measure
Causes of eosinopenia
- Stress
- Bacterial infections
- Viral infections
- Steroids
Definition of basophilia
Increase in basophils > 0.2 x 10^9/L
Causes of basophilia
- Allergies
- Hypothyroidism
- MPN
Definition of basopenia
Decrease in basophils is difficult to measure and is not significant
Causes of basopenia
- Hyperthyroidism
- Stress
- Infection
Definition of monocytosis
Increase in monocytes > 1.3 x 10^9/L
Causes of monocytosis
- Hematologic disorders (MDS, AMML, CMML, AMoL)
- Connective tissue disorders
- Infections (recovery from infection is a good prognosis)
Definition of monocytopenia
Decrease in monocytes < 0.1 x 10^9/L
Causes of monocytopenia
- Hairy cell leukemia
- Counts fall transiently after administration of prednisone
Definition of lymphocytosis
Depends on age
- Adults: > 4.5 x 10^9/L
- Children: > 11.1 x 10^9/L
Causes of lymphocytosis
- Infectious mononucleosis (EBV most common)
- Infectious lymphocytosis
- Bordetella pertussis (in children)
Definition of lymphocytopenia/lymphopenia
Depends on age
- Adults: < 0.8 x 10^9/L
- Children: < 1.5 x 10^9/L
Causes of lymphocytopenia
- Immunologic disorders (SCID, DiGeorge Syndrome)
- Chemotherapy, radiation
- Immunosuppressive agent (steroids)
What is the significance of the absolute neutrophilc count (ANC) to an oncologist?
It’s an assessment of the patient’s risk of contracting a potentially life-threatening infection
