Download basic haematology - Woodley Equipment

BASIC HAEMATOLOGY
BLOOD CONSTITUENTS
RBC’S
WBC’S
PLT’S
PLASMA
BONE MARROW
STEM CELLS
WBC’S
Late normoblasts
Reticulocytes
RBC’S
Megakaryocytes
Granulocytes
Non-granulocytes
Neutrophils
Lymphocytes
Eosinophils
Monocytes
PLT’S
Basophils
Notes
RBC’s – Live ~ 120 days
Spleen; Hb broken down in Liver to Bile Acids
& Bilirubin. NB. Decrease in size as they get older.
Lymphocytes
B-Lymphocytes (Bone Marrow) – Produce Ab’s against invading antigens eg.
Viruses.
T-Lymphocytes (Thymus) – Ab’s are bound to the cell membrane (“Killer” T
cells).
Monocytes
Phagocytic - “eat foreign bodies, antigens, debris, etc.
Neutrophils & Eosinophils
Contain proteolytic enzymes to break down cell walls.
Basophils contain Histamine & Heparin (Inflammatory processes) and are also
thought to be involved in the metabolism of Fat.
Erythropoietin – produced by Kidneys in response to low O2 levels in blood gives
increase in RBC’s.
RED BLOOD CELLS – ERYTHROCYTES
ANAEMIA
Decrease in Hb, HCT, & RBC’s
 Blood Loss (Internal/External Bleeding)
 Haemolysis (destruction)
 Bone Marrow Disease
 Iron Deficiency (Haemoglobin)
Bone Marrow Disease
 Non-regenerative Anaemia – No Retics despite Anaemia
 Regenerative Anaemia – Bone Marrow
Retics
RDW
RDW
RBC
No’s
RBC Size
Retics present
Retics Present
(Larger RDW)
Increased MCV
Decreased MCHC
Iron Deficiency
Lack of Hb
Smaller RBC’S with less Hb
(MCV Decreased) (MCHC Decreased)
NB. Decreased MCV also results from Porto-systemic shunts due to Iron
assimilation in the Liver.
POLYCYTHAEMIA
Increase in RBC’s
 Dehydration
 Bone Marrow disease
 Rarely – Cardiovascular Disease; Kidney malfunction; Polycythaemia vera
Megakaryocytes
PLATELETS – THROMBOCYTES
Platelets
Blood Clots
Thrombocytopenia (increase) – If MPV unchanged evaluate bone marrow.
Thrombocytosis (decrease) – Blood loss; Iron deficiency;
Bone Marrow Cancer.
WHITE CELLS – LEUCOCYTES
LYMPHOCYTES
Produce Ab’s against non-bacterial diseases ie. Viruses
Lymphocytosis (Increase)
 Viral diseases
 Stress (Cats & Horses) due to Adrenaline.
 Leukemia
Lymphopenia (decrease)
 Steroid therapy
 Steroid release from Adrenals (Cushings)
 Distemper or Parvo
MONOCYTES
2nd line of defence against Micro-organisms/Bacteria (after Neutrophils)
Monocytosis – Chronic disease; Stress; Steroid diseases
Monocytopenia – Irrelevant in Vet. Medicine
NEUTROPHILS
1st line of defence against Micro-organisms/Bacteria or inflammatory diseases.
Neutrophilia – Band Neutrophils (immature forms) released form Bone Marrow in
response to inflammation. (Left – shift).
- Chronic stress – due to steroid release (eg. Cushings) but no
bands.
Neutropenia – Invader is winning
EOSINOPHILS
Eosinophilia – Hypersensitivity (Allergic Reactions)
- Parasites (Fleas, Ticks, worms in horses)
Eosinopenia – Steroid mediated stress.
BASOPHILS
Normal to have none.
Basophilia – Very rare in Vet. Medicine
- Hypersensitivity (as above)
- Very rare cancers in dogs.
Basopenia – Does not exist.
HAEMATOLOGY ANALYSERS
12ul sample
~6 x 106 /mm RBC’s
PLT’s
(+WBC’s very small nos)
~10 x 103 /mm WBC’s
Hb
(RBC’s lysed
Hb)
1/20,000 Dilution
1/300 Dilution
REQUIRE A FLOW OF SINGLE CELLS
Two commonly used methods:
Laminar flow Cytology
(Hydrodynamic Focusing)
0
0
0
0
Small aperture aspiration
o
0
24 hour maintenance.
 CDC – WBC’s & RBC’s
 Sysmex – WBC’s
 Celldyne – WBC’s & RBC’s
Partial
vacuum
ABC – WBC’s & RBC’s
HMT – WBC’s & RBC’s (MS5)
Sysmex – RBC’s
Celldyne – WBC’s & RBC’s
Cellyvet – Vetlab
Medonic – Menarini
COUNTING METHODS
a) Impedance
To achieve diff use “lyse” reagent that shrinks white cells.
Eg. ABC: Lympho’s>Mono’s>Neutro’s>Eosino’s
b) Laser Scatter (eg. Sysmex, Celldyne, Lazercyte)
Sensor
Source
Side Scatter
Front
Scatter
Monocytes
Sensor
Lymphocytes
Front Scatter
Side Scatter
OTHER TYPES OF HAEMATOLOGY ANALYSERS
a) VS2000 – Hematek
OHP’s
b) QBC – Quantitative Buffy – Coat
Haematocrit tubes coated with fluorescent dye which results in differential
staining of DNA & RNA in the White cells, Reticulocytes & Platelets.
Uses small plastic “float” to separate white cells in Buffy Coat.
Buffy Coat
P BENM L R
PLASMA
Detector
RBC’s
UV Source
NB. Floating discriminators in Impedance/ Laser Scatter Counters simply refer to
the ability to change cut-off points between different types of cells in different
species.
Viz a viz Smart Cards in the ABC.