WBC Physiology Flashcards
(29 cards)
Myelocytic Maturation series
myeloblast
promyelocyte
myelocyte
metamyelocyte
*non-segmented granulocyte (band neutrophil)
*segmented granulocyte (segmented neutrophil)
What regulates leukopoiesis?
Colony stimulating factors (CSF) such as:
- CSF-GM: stimulates granulocytes and monocytes
- CSF-G: stimulate neutrophils (granulocyes)
*these factors stimulate maturation events
Name some of the nuclear and cytoplasmic “altered” cell morphologies
Nuclear:
-Pelger-Huet: autosomal dominant genetic disorder leading to hyposegmentation
Cytoplasmic:
-Gaucher: glucocerebroside accumulates in cells of liver and spleen. Massive hepatomegaly andd splenomegaly.
- Niemann-Pick: myelin accumulation in cells (lysosomes)
- Toxic Granulation: changes in granulocytes on peripheral blood smear(coarse deeply colored granules), occurs w/ infections of cell surface
-Dohle Bodies:
grey-ish blue areas in the cytoplasm representing residual ribosomes/RNA.
Vacuolization: occurs under stress, holes?
Leukocyte Differential: expected % seen in peripheral blood smear.
Segmented Neutrophil: 50-70%
Lymphocytes: 20-40%
- -60-80% T cells
- -10-20% B Cells
- -5-10% NK
Monocytes: 0-7%
Neutrophil Bands 0-5%
Eosinophils 0-5%
Basophils 0-1%
When would you see an increase in the number of neutrophil bands on peripheral blood smear?
-pyogenic infection
What are two type of electronic blood cell counters?
- Coulter Principle
- Flow Cytometry
- -forward scatter: size
- -side scatter: granularity
What is hypersegmentation?
First hematologic abnormality seen in what disorders?
- abnormally increased nuclear lobulation
- megaloblastic, B12 and Folate deficiency, iron deficiency anemia
On average how many lobes does a mature circulating neutrophil have?
eosinophil?
basophil?
-3-5
-
What are the requirements for hypersegmentation?
aka
- more than 3 cells having 5 lobes or a single cell with 6 lobes found in the course of 100 cells is evidence of hypersegmentation.
- “right shift”
What is hyposegmentation?
-neutrophils with few than 3 lobes
What is the cause of toxic granulation?
- seveere inflamm states (sepsis)
- thought to be d/t impaired cytoplasmic maturation, in the effort to rapidly generate large numbers of granulocytes
What is vaculoization helpful in diagnosing?
-dx of septicemia(blood poisoning)
What are the suffixes used to describe quantitative disorders of WBC?
- penia (low count)
- philia (high count)
What is the cause of pseudneutrophilia?
Left shift?
Sustained neutrophilia?
- demargination of marginated pools of cells. (dbling of count)– Stress
- acute inflamm
- chronic infection
What is the consequence of giving glucocorticoids during an infection in relation to the leukocytes?
it decreases extravasation into the tissues leading to leukocytosis in the circulating pool.
What artifacts suggest “toxic” cell appearance in neutrophilia?
- Dohle Bodies
- Vacuoles
- Intra-cellular microbes
When are Dohle Bodies present in the cytoplasm of cells?
-infections, poisoning, burns, and following chemotherapy, neoplastic disease, myeloproliferative disorders, pregnancy
What are some causes of neutrophilia?
- Physiologic:
- -emotional stimuli: fear, panic, joy, excitement, depression
–Physical stimuli: cold, heat, exercise, pain, menstruation, labor, pregnancy, vomiting, smoking
- Infections/inflamm
- -bacterial
- -parasitic
- Tissue Necrosis:
- -acute gout
- -burns
- -trauma
- infarcts
Metabolic:
- ketoacidosis
- uremia
- eclampsia
- thyrotoxicosis
Other:
- -autoimmune
- -myeloproliferative disorders
- Drugs/Hormones:
- -epinepherine
- -steroids
- -lithium
- -venoms/poisons/toxins
What can cause neutropenia?
- age
- race (african, middle eastern)
- rxn to drug
- infections (HIV/Hepatitits, TB, Malaria)
- immune disorders (SLE)
- Neoplasm
- BM failure (megaloblastic anemia, aplastic anemia)
- Idiopathic
Pathophys of Neutropenia?
Defects inside or outside the BM
- decreased proliferation (aplasia)
- decreased maturation (insufficient number of precursors)
- decreased survival (increased destruction)
- Distribution (total body pools are normal, circulating numbers reduced) (Increased margination)
Causes of Lymphocytosis
- infection
- -viral (CMV, EBV)
- -bacterial (Pertussis)
- Meds (Dilantin)
- Rx
- Neoplasm
- -leukemias
- -lymphomas
Pathophys of Lymphopenia
- decreased production
- increased destruction
- changes in distribution
Causes of lymphopenia
- Decreased production:
- -SCID (severe combined immunodeficiency)
- -protein-calorie malnutrition
- -zinc deficiency
- Increased Destruction
- -HIV
- -Radiation therapy
- -chemotherapy
- -SLE
- Redistribution:
- -glucocorticoid therapy
- Anesthesia
- TB
- Flu
- Burns
HEMATOLOGIC DISORDERS
Causes of Monocytosis
- Hematolgic disorders
- -leukemia
- -lymphoma
- Infections
- -TB
- -SBE (Subacute bacterial endocarditis)
- Fever of unknown origin
- GI disorder
- Collagen vascular disorders
