Abnormal white cell count Flashcards
What is haemopoeisis?
Production of blood cells in marrow
- Normal haemopoiesis - polyclonal healthy/reactive (normal marrow, reactive marrow)
- Malignant hamopoiesis - abnormal/clonal (leukaemia –> all from the same stem cell mother)
What is the process of differentiation and maturation?
In the bone marrow.
Myeloblast (very large and poorly differentiated - similar to lymphoblast (differentiated by the granules in the myeloblast) –> high nucleus to cytoplasm ration.
—–> Promyelocyte (smaller nucleus and more granules)
—> myelocytes
—> metamyelocyte (nucleus is starting to fold)
–> band cells
–> Neutrophils
(in normal conditions should only see the mature neutrophils in the peripheral blood - only see the myeloid precursors in leukaemia + sepsis)
How are the cell number controlled?
Cytokines influence differentiation and proliferation G-CSF (granulocyte) and M-CSF (myleocyte)
DNA directed differentiation and proliferation ; DNA damage = cancer
If a person is anaemic can be given recombinant erythropoietin.
What are the causes of an abnormal WBC count?
Cell production:
- Reactive (infection + inflammation) [increase]
- Malignant (leukaemia + myeloproliferative) [Increase]
- Impaired BM function [decrease]
- B12 or folate deficiency [decrease]
Cell survival:
- Failure of apoptosis (e.g. due to cancer) [increase]
- Immune breakdown [decrease]
What are the WBC found in the bone marrow?
Myleoblasts
Pronyleoblasts
Myleocytes
Metamylecoytes
What is eosinophilia?
An increased number of eosinophils
Normal production stimulated by:
- inflammation
- infection
- increase cytokine production
Abnormal production due to:
- Cancers of haemopoietic cells
- Leukaemia (myeloid or lymphoid, chronic or acute)
- Myeloproliferative disorders
What is the process of malignant haematopoiesis?
Mutation is at a very early stage of stem cell differentiation.
Very high white blood cell count especially neutrophils
How to investigate an raised WBC count?
History and examination - fatigue, weight loss (investigate symptoms) , recreational lifestyle (smokers have high neutrophil count)
Hb and platelet count
Automated differential
Examine blood film
What are the causes of elevated WCC?
Mature cells:
-Reactive/infection
–> all lineages
Lymphocytes
Mature + immature:
–> neutrophils + myleocytes + basophills (chronic leukaemia)
Immature:
–> Blasts + low hb + low platelets (acute leukaemia)
…………..
Describe neutrophils :
Life span 2-3 days
In Bone marrow, blood and tissues
develop in minutes to ————-
What are the causes of neutrophilia?
Infection
Tissue inflammation
Physical stress, adrenaline, corticosteroids
Underlying neoplasia
Malignant neutrophilia
- myeloproliferative disorders
- CML
In infection - localised and systemic
What are the causes of eosinophilia?
Parastic infection
Allergic diseases
Neoplasms
Hypereosinophilic syndrome
Malignant chronic eosinophilic leukaemia
What is monocytosis?
what is lymphocytosis?
In elderly patients
Mature lymphocytes
To distinguish:
- Morphology
- Immunophenotype
- Gene re-arrangement
What is reactive lymphocytosis?
