Lecture 11 - Introduction to Disorders of WBC - Non-neoplastic Disorders

Question 1

Reactive Haematological Disorders

Answer 1

Changes in haematological values that occur in response to stimulus
- = non-neoplastic
With respect to leukocytes may be
- Quantitative - altered concentration of leukocyte(s)
- Qualitative - altered morphology of function of leukocytes

Question 2

Quantitative Disorders: Temporal Effects

Answer 2

The [WBC], [neutrophil] etc. may change throughout the course of a disorder:

1. ‘Natural course of a disorder => inflammation
   - emigration of neutrophils from circulation
   - release of neutrophils in bone marrow
   - increased myelopoiesis
2. In response to intervention
   - e.g. antibiotic therapy, surgical removal of the site of inflammation

Question 3

Qualitative Disorders

Answer 3

Function of neutrophils typically not assessed by automated haematology analysis (FBC)
May be assessed by blood film examination
- morphology

Question 4

Appendicitis

Answer 4

Inflammation of the appendix
Leukocyte changes commonly present
The WBC count for stages of appendicitis:
1. Early appendicitis - 14.5 +- 5
2. Suppurative appendicitis - 17 +- 5
3. Perforative appendicitis - 20 +- 7.5

Question 5

Why is there often a wide range of WBC values encountered in inflammatory disorders?

Answer 5

Variation of the disease
Progression of the disease
‘Balance’ of emigration of cells from the blood and production/release of cells from the bone marrow
Therapeutic interventions

Question 6

Sepsis

Answer 6

Systemic inflammatory response to microbial infection
Is rapidly progressing, life-threatening condition that can cause shock and organ failure
FBC leukocyte characteristics include:
1. Variable leukocyte response
- leukocytosis, leukopenia, normal
2. Variable neutrophil response
- neutrophilia, neutropenia, normal
3. Morphological atypia
- left shift
- Dohle bodies
- toxic granulation
- vacuolation
4. Presence of microorganisms
Typically increased WBC and neutrophils compared to controls

Question 7

Severe Sepsis

Answer 7

Typically increased WBC and neutrophils compared to controls
Severity of sepsis not necessarily reflected in the magnitude of the [WBC]
- some results within the range of control values
Consider left shift, morphology of WBC as well as [WBC]

Question 8

WBC Count, % Neutrophils, and Total Neutrophil Counts for Normal and Severe Sepsis

Answer 8

Sepsis:
WBC count - 8.8-12.6
% - 86-92
Neutrophils - 6.5-15.6
Severe Sepsis 
WBC count - 6.8-10.8
% - 84-95
Neutrophils - 3.4-13.5

Question 9

Systemic Inflammatory Response Syndrome (SIRS)

Answer 9

Inflammatory state affecting the whole body, frequently a response of the immune system to infection
Related to sepsis 
Counts:
WBC count - 7.5-12
% - 73-86.6
Neutrophils - 3.2-11

Question 10

Infectious Organisms

Answer 10

Some infectious organisms may be observed in peripheral blood
These may be observed:
- circulating within the blood 
- phagocytosed by leukocytes
Include:
- bacteria
- fungi

Question 11

Bacteria

Answer 11

Many possible bacteria may be encountered in the peripheral blood
Increased likelihood in immunocompromised patients
Granulocytes contain toxic vacuoles and intracellular rod shaped structures suggestive of phagocytosed bacilli

Question 12

Fungi - Candida Albicans and Histoplasma Capsulatum

Answer 12

Candida albicans
- yeast form fungus
- typically in immunocompromised patients
Histoplasma capsulatum
- yeast form fungus
- inhalation of spores => progressive dissemination

Question 13

Infectious Mononucleosis

Answer 13

Lymphoproliferative disease
Infects B lymphocytes
Infection controlled by cell mediated responses (T lymphocytes)
Usually occurs in young adults
Transmission through saliva
Disease is self-limiting; recovery weeks to months
Laboratory findings:
WCC
- 12-25 x 10^9/L
- lymphocytosis; > 50%
Morphology
- t lymphocytes 'reacting' to infected B lymphocytes
- => reactive lymphocytes present
- atypical 
Confirmation based on serology
- monospot test
- EBV IgM, IgG

Question 14

Reactive Lymphocytes

Answer 14

May occur with viral diseases
- e.g. cytomegalovirus
- chicken pox
May occur with some bacterial diseases
- e.g. whooping cough
May occur with antigenic stimulation
- e.g. vaccination

Question 15

Examples of Qualitative Disorders - Congenital and Acquired

Answer 15

Congenital & Acquired
- adhesion defects
- granule defects
- phagocytic defects
- chemotactic defects
Different examples in each for congenital and acquired but fuck me there's heaps and I cbf writing them all down

Question 16

Chediak-Higashi Granules

Answer 16

Granule defect of congenital origin
Grey granules in neutrophil cytoplasm
- also platelet melanocytes
Autosomal recessive disorder of storage/secretory granules
- => dysfunctional bactericidal activity