Haematology

Parameter PARAMETER LASERCYTE QBC VETAUTOREAD IMPEDANZ SYSTEM Hct Yes Hgb RBC Retics Up to 4% MCV RDW MCHC MCH WBC LYM Yes ( Small ) MONO Yes ( Middle ) NEU Yes ( Large ) EOS Dogs and Cows BASO PLT PCT PDW MPV FIBRINOGEN NRBC’s

Eosinophils Eosinophilia Most frequent causes Least frequent cause Parasitic and allergic processes Heartworm, Strongyle, Lung Flukes Feline asthma, Flea bite dermatitis Least frequent cause Neoplasia, Fungal Infecion Viral Infection ( FeLV ) Eosinopenia When concurrent with lymphopenia is usually due to stress QBC in dogs

What can cause changes in blood values? Infections Bacteria Viral Funghi Inflammation Intoxication Stress Anaemia Tumors Bleeding disorders Autoimmun diseases

Why run Haematology inhouse? Blood samples consist of living cells and should therefore be analysed as quickly as possible, to avoid: Changes in cells because of storage and transport To minimise artefacts which can develop if the sample has contact to EDTA for a longer period of time So treatment decisions are based on todays situation and not yesterdays Alterungsprozesse: 4h Katze und Hund –8h Pferd Agglutinieren, Größe und Morphologie verändert sich Z.B Schwellen Erys nach 6-24 an und können so den HKT fälschlicherweise erhöhen und den MCHC erniedrigen

Fresh Sample versus 48hr Sample

CBC Granulocytes Agranulocytes Red cells (Erythrocytes) White cells (Leucocytes) Granulocytes - Neutrophiles - Eosinophiles - Basophiles Agranulocytes - Lymphocytes - Monocytes Platelets (Trombocytes)

White differentials Typical “2 part” Diff Typical “5 part” Diff Agranulocytes Granulocytes Typical “3 part” Diff Lymphocytes Monocytes Typical “5 part” Diff Lymphocytes Monocytes Neutrophile Grans Eosinophile Grans Basophile Grans Bezieht sich nur auf Weißes Blutbild beziehungsweise die Unterteilung der Leukozyten in Agran und Gran Dann Unterscheidung der Agranulozyten in in Lymp/Mono Dann Gran in N, E, B

What differentials do you get with.. QBC Autoread LaserCyte ? QBC 2 teilig Impedanz 3 teilig Impedance System

Why can’t an impedance system give you a 5 part diff SIZE MATTERS ! A) basophil B) neutrophil C) eosinophil

LaserCyte…. Cells focused into a stream that passes through a laser light that interrogates them. Light scatter is sensed by four photodiodes. Time of flight measurement also taken. Initial RBC count and platelet count taken. The RBC’s are then lysed using a mild agent. 5 part differential then performed qualiBeads are run with every sample. These act as an internal standard for quality assurance.

LaserCyte Technologie...

QBC Autoread… The QBC uses centrifugation to separate cells by density. The ‘float’ in the QBC tube reduces the volume of lumen in the area of the buffy coat. This causes the cells to be spread out over a greater distance. Cells take up the ‘acridine orange’ present in the tube (DNA and RNA/Lipoproteins). Cell types are differentiated by the location and intensity of dye.

QBC VetAutoread

Coulter® Principle Impedance counters rely on the Coulter principle. When a particle passes through a narrow orifice, it causes a change in resistance. The magnitude of the change corresponds to cell size and the number of changes corresponds to cell size.

Interfering Substances 3 Part Impedance Technology Giant / Clumped Platelets Results in erroneously low platelet counts. Erroneously high WBC count. Can also be misclassified as RBC’s. nRBC’s and unlysed RBC’s Unable to classify nRBC’s. nRBC’s result in erroneously high WBC count Excessive eosinophils, metamyelocytes, blasts and plasma cells. Can cause erroneous monocyte count Leukaemia and chemotherapy Harsh lysing agent can damage fragile cells

Interfering Substances.. High WBC count WBC’s counted during RBC count. This can effect the red cell parameters. (Hct, RDW,MCV and RBC) Agglutinated red cells Can cause erroneously low RBC and can trap platelets. Microcytic cells and fragments Can effect platelet count Microzyten: sehr kleine Erys, meist degeneriert oder Mangelbildungen

Interfering Substances…. How does the operator know if you have abnormal cells present that may affect the results ? How do they know if the results are due to the clinical condition or erroneous reading caused by abnormal cells? Would you trust a system that could not flag ‘suspect’ results ?

Parameter PARAMETER LASERCYTE QBC VETAUTOREAD IMPEDANZ SYSTEM Hct Yes Hgb RBC Retics Up to 4% MCV RDW MCHC MCH WBC LYM Yes ( Small ) MONO Yes ( Middle ) NEU Yes ( Large ) EOS Dogs and Cows BASO PLT PCT PDW MPV FIBRINOGEN NRBC’s

ABC Analyser – The Bad ! No retic information 3 Part Diff Impedance technology Interfering substances 160 cycles include calibration / flushes / start up runs etc No data storage Few or no flags on abnormal samples Needs recalibrating every 6 months Different smart card per species Problematisch: Thrombozytenagglutinate bei Katzen, aber auch Thrombos und Erys bei Katze generell ähnlich groß nRBC, Hülle lysiert, Kern nicht wird als Leukozyt gezählt große Lymphozyten und kleine Neutrophilenkerne werden als Monocyten gezählt Da nur Partikelgrößenmessung: Fehlinterpretation von Thrombozytenaggregaten, nRBC und großen Thrombozyten als z.B. Leukozyten