Clinical Pathology Flashcards
What is the average life of a platelet?
10d
Which blood cell component has the shortest life span?
Neutrophils
How long do RBCs last in cats and dogs?
Cat 70d
Dog 110d
An increase of what signals an extravascular lysis?
Bilirubin?
An increase of what signals an intravascular lysis?
Free Hb
What change to neutrophil populations may be seen with severe inflammation?
Juvenile (Band) neutrophils present – called Left Shift.
If v severe - neutropenia
When are nucleated RBCs seen in circulation?
accelerated erythropoesis OR BM damage
When are reticulocytes seen in circulation?
inc # in accelerated erythropoesis
Which stain canbe used to visualise reticulocytes clearly?
New Methylene Blue
Where is EPO produced?
Kidney - response to O2 insufficiency
Where is TPO produced?
liver - constantly
Which tube should be used for routine haematology?
EDTA
Which tube should be used for a blood smear?
syringe/sterile
What does MCV assess? How does it help to classify anaemia?
RBC size (Avg)
Macro/normo/microcytic
What does MCHC assess?
Average RBC Hb concentration
Which type of anaemia is indicated by macrocytosis?
Regenerative
Which type of anaemia is indicated with normoocytosis?
non-regenerative
Which type of anaemia is indicated by microcytosis?
Iron Deficiency
Which type of anaemia is indicated with hypochromic RBCs?
Regenerative or Iron Deficiency
What is the most sensitive way of assessing if an anaemia is regenerative?
BM examination
What is the most commonly used way of assessing if an anaemia is regenerative?
Reiculocyte Enmeration - BM assessment invasive and expensive
If assessing RBC regeneration via polychromasia, what value indicates non-regenerative anaemia?
<2 polychromatophils/HPF (x100)
What changes can be seen on haematology of a patient who has suffered a haemorrhage in recent hours?
Dilution –> reduced Hct and TP
The presence of which cells indicate IMHA?
Shperocytes - small, without central pallor
What RBC clumping pattern is suggestive of IMHA?
Agglutination
What RBC clumping pattern is normal in horses?
Rouleaux
In the saline Agglutination test - do rouleaux or agglutinates persist?
Agglutinates!
An increase of which WBC may indicate adrenaline release in cats?
Lymphocytes
What does a monocytosis indicate?
Chronic inflammation
What does a moderate lymphocytosis indicate?
Chronic inflammation
What does a severe lymphocytosis indicate?
Leukaemia
What does a lymphopenia indicate? (3)
Acute inflammation
Stress leucogram
Viral Infection
What does a Neutrophilia indicate?
Inflammation
What does a Neutropenia indicate?
Overwhelming demand
Reduced BM production
Inc destruction
What does a left shift indicate?
Severe acute inflammation
What may an eosinophilia indicate?
Worm parasitism
Allergy (T1 hypersensitivity)
What are the 4 classes of thrombocytopenia?
Destructive
Consumptive
Reduced Production
Distributional
What are the possible causes of a destructive thrombocytopenia?
IMTP: AI, drug reaction, ID, neoplasia
What are the possible causes of a consumptive thrombocytopenia? (4)
DIC
Thrombosis
Vessel Inflm
Acute, severe blood loss
What is the cause of a reduced production thrombocytopenia?
BM damage
What are the possible causes of a distributive thrombocytopenia?
Splenomegaly
Severe Hypothermia
Endotoxaemia
What is the clinical significance of thrombocytosis?
None
What are the 3 main characteristics of ACUTE inflammation?
Oedema
Neutrophils
Inc Blood Flow
What are the 4 main characteristics of CHRONIC inflammation?
Lymphocytes/mø
BV proliferation
Fibrosis
Necrosis
Define Exudate
Escape of fluid, protein AND blood cells FROM vascular system.
What is the gross appearance of an exudate?
Turbid, opaque, variable colour
Define Pus.
Inflammatory exudate rich in leukocytes and cell debris
What are the two changes to the vasculature which occur with acute inflammation?
Vasodilation
Increased vasc permeability
What are the 5 stages of leukocyte extravasation?
Rolling Activation Adherence Transmigration Migration
When do neutrophils predominate at the site of inflammation?
6-24h
When do macrophages predominate at the site of inflammation?
24-48h
What is the first stage of fibrosis?
Granulation tissue formation
What are the 4 stages of CT repair?
Angiogenesis
Mig/prolif of fibroblasts
ECM deposition
Remodelling of fibrous tissue
What is the predominant cell type in granulomatous inflammation?
Activated Mø
Describe the structure of a granuloma.
Centre: caseous necrosis w/calcification
Surrounded by epithelioid møs
Periphery: lymphocytes
Which agent is most known for inducting granulomatous inflammation?
Mycobacteria
What is healing under primary intention?
Wounds with opposed edges - surgical
What is healing via secondary intention?
more inflammation, larger granulation tissue and wound contraction present
How long does a blood clot take to form in 1e vs 2e intention healing?
1: 24h
2: 2-3d
How long does a granulation take to heal the gap in 1e vs 2e intention healing?
1: 2-7d
2: 1-2w
How long does a initial, weak scarring take to form in 1e vs 2e intention healing?
1: 2-4w
2: 3-6w
Which 2 systemic factors influence wound healing?
Nutrition
Hormones