6: Haematology 4 Flashcards
Which cytokines stimulate myeloblast production?
IL-1 and IL-6
When are IL-1 and IL-6 produced?
Inflammation
In which pool do myeloblasts become myelocytes?
Proliferative
In which pool do metamyelocytes become mature cells?
Maturational pool
Which pool are myeloid cells released from during inflammation?
Storage
What is the half life of a lecuocyte?
6-14 hours
In health, where are lecocytes lost?
Across mucosa or phagocytosed in liver/spleen
Which are the two leucocyte pools in the blood?
Circulating and marginating (on endothelium)
Which leucocyte pool is measured?
Circulating
Which conditions can decrease leucocyte adhesion?
Endotoxaemia, steroids, glucocorticoids
What is the usual marginating:circulating leucocyte ratio?
1:1
What is the marginating:circulating leucocyte ratio in cats?
3:1
How do cytokines affect marginating pool?
Increase
How many lobules does the neutrophil nucleus have?
3-5
Does acute or chronic inflammation cause neutrophilia?
Both
Which pool are neutrophils released from following inflammatory mediators in acute inflammation?
Storage or maturational
Which kind of inflammation causes granulocytic hyperplasia?
Chronic
Why do you only see mature neutrophils in chronic inflammation?
Although proliferative and maturational pool size increase, neutrophil must be mature before release
Which cells can show left shift and toxic changes?
Neutrophils, lymphocytes, eosinophils
What does the nucleus look like in left shift?
Non-lobulated
What kind of neutrophils are released in left shift?
Band
Where are band neutrophils released from?
Bone marrow
Which kind of diseases cause toxic changes?
Infectious (severe)
In which species are Dohle bodies normal?
Cats
What do toxic changes look like?
Basophilia, vacuolation, doughnut nuclei, giant cells
What is the leukaemoid response?
Marked neutrophilia from severe inflammation
What neoplastic condition resembles the leukaemoid response?
Chronic granulocytic leukaemia
When may chronic inflammatory neutrophilia show left shift?
If inflammatory stimulus is large
Which cell number changes do you also see in chronic inflammatory neutrophilia?
Monocytosis, lymphocytosis, eosinophilia
Which shift can you get in chronic inflammatory neutrophilia?
Right or left - but usually mature
What do right shift neutrophils look like?
Hypersegmented older cells
What normally causes right shift?
Steroid therapy or chronic inflammation
What does bone marrow show in chronic inflammatory neutrophilia?
Granulocytic hyperplasia
Why do cattle not show neutrophilia in infection?
Limited storage pool
Why do cows get neutropenic in infection?
Cells move into tissues
What 3 conditions can cause stress-induced neutrophilia?
Stress, steroids, Cushings
What two processes cause the neutrophilia following stress?
Lose endothelium adhesion, more released from marrow storage pool
Which species gets marked stress-induced neutrophilia?
Cats
Why is stress-induced neutrophilia only 2-4x the reference interval?
Limited number in marginating pool
What does a stress leukogram look like?
Neutrophilia, monocytosis, lymphopenia, eosinopenia
What happens during excitement neutrophilia?
Redistribution to circulating pool
How fast does excitement neutrophilia normalise?
Quickly, esp healthy animals
How many times reference interval does excitement neutrophilia cause?
2-4x
Which cells are also increased in excitement neutrophilia?
Lymphocytosis but no monocytosis
How common is granulocytic leukaemia?
Uncommon
What do cells look like in granulocytic leukaemia?
Morphologically normal, high neutrophil count with left shift
How do you diagnose granulocytic leukaemia?
Exclusion
Which condition does granulocytic leukaemia resemble?
Leukaemoid response in inflammation
Which proteins are helpful to diagnose granulocytic leukaemia?
Acute phase proteins (will be high in inflammation)
What causes paraneoplastic neutrophilia?
Neoplasms release cytokines and stimulate granulopoiesis
How can paraneoplastic neutrophilia resolve?
treatment or tumour removal
What do neutrophils look like in paraneoplastic neutrophilia?
Left shift
How does sedation affect neutrophils?
Neutropenia
Which breed has especially low neutrophils?
Greyhounds
What is happening during inflammatory neutropenia?
Overwhelms white cell production - more moves to tissues than released
Which conditions often cause inflammatory neutropenia?
Pyo, metritis
Which kind of bacteria can often cause inflammatory neutropenia?
Gram -ve
In which species is inflammatory neutropenia common?
Cattle
Which conditions can cause bone marrow hypoplasia?
Toxins esp oestrogen, chemo, infections esp FeLV, parvo
Which conditions can cause myelophthesis?
Neoplasia, myelofibrosis
Which breed gets cyclic haematopoiesis so see severe neutropenia then recovery?
Grey collies
How do you tell bone marrow hypoplasia and inflammatory neutropenia apart?
No left shift/toxic changes in bone marrow hypoplasia
Which WBC is most common in cattle?
Lymphocytes
What size are lymphocytes compared to neutrophils?
Smaller
When do you see large lymphocytes?
Immune stimulation or lymphoma/leukaemia
How are lymphocytes affected during excitement?
Mild increase
How can vaccination affect lymphocytes?
Lymphocytosis if young
How can Addisons affect lyphocytes and eosinophils?
Lymphocytosis, eosinophilia
How does acute inflammation affect lymphocytes?
Lymphopenia
How does loss of lymph affect lymphocytes?
Lymphopenia
What shape are eosinophils in cats?
Rod-shaped
Which kind of inflammation causes eosinophilia?
Parasitic and allergic
Which areas of the body do eosinophils release caustic enzymes in?
Skin, GI tract, resp tract
How does Addisons affect eosinophils?
Inverse stress leukogram - so eosinophilia, leukocytosis
Why do mast cells especially cause paraneoplastic eosinophilia?
Histamine stimulates eosinophils
Which species gets hypereosinophilic syndrome?
Cats
Which organs are infiltrated by eosinophils in hypereosinophilic syndrome?
Liver, spleen, GI tract, bone marrow
What may possibly cause hypereosinophilic syndrome?
Eosinophilic leukaemia
How common is eosinopenia?
Rare and not relevant
What may cause eosinopenia?
Acute inflammation or stress/steroids
For how long do monocyes remain as macrophages?
years
How common in monocytic leukaemia?
Rare
How common is paraneoplastic monocytosis?
Rare
Which conditions cause increased basophils?
Parasitic or allergic
Which cell changes do basophils mirror?
Eosinophil
Which cells produce thrombopoietin?
Hepatocytes and renal tubular cells
Which cells does thrombopoietin act on?
Megakaryoblast and megakaryocyte
When is TPO produced?
Constantly
How is TPO cleared?
When taken up by platelets and megakaryocytes
Which hormone controls platelet production?
TPO
What happens to TPO if there is less platelets?
More
What happens to TPO secretion in inflammation?
Increases
How long does platelet production take?
3 days
How long do platelets live before they are cleared by the spleen?
6 days
What breeds especially get pseudothrombocytopenia?
CKCS, sighthounds
What can happen to large platelets causing low platelet count?
Sequestered in spleen
Which conditions cause increased platelet consumption?
DIC, vasculities, endocarditis
Which conditions causes increased platelet destruction?
IMTP
Which conditions can cause decreased platelet production?
Drugs, infectious agent, myelophthesis
WHat do stress leukogram and chronic inflammatory neutrophilia both show?
Neutrophilia, monocytosis
What are lymphocytes and eosinophils like in stress leukogram vs chronic inflammatory neutrophilia?
Stress leukogram has lymphopenia and eosinopenia but CIN has the opposite
How does thrombocytosis cause pseudohyperK?
Platelets release potassium when they clot
Is thrombocytosis clinically relevant?
No
How common is megakaryocyte neoplasia?
Rare
What condition can cause decreased platelet removal?
Splenectomy
What happens to platelets in excitement?
Released from spleen
Which four conditions can cause increased platelet production?
TPO in inflammation, iron deficiency, vincristine therapy, rebound after thrombocytopenia
