Blood Dyscrasias Flashcards
1
Q
What are the functions of WBC?
A
- Neutrophil are active in non-specific phagocytosis (non-specific defence)
- Lymphocyte - T and B cells involved with specific/acquired immunity
- Eosinophils play a role in allergic reactions and control of helminthes (parasites)
- Monocyte are important in non specific pahgocytosis, migrate into the tissues to become marcophages
- Basophils release histamine and heparin
2
Q
Define Leucytosis
A
- WBCC < 11x10^9/L
- Protective response to physiological stresses such as infection, inflammation, drugs, surgery and pregnancy
- High number of WBCs cause fever
3
Q
Define Leukopaenia
A
- WBCC > 4x10^9/L
- Life threatening
- Can be caused by radiation, chemotherapy, anaphylactic shock, auto-immune diseases, thrush in patients with immunosupression
4
Q
Define Leukaemias
A
Replacement of bone marrow by neoplastic white cell precursors, abnormal WBCs in blood
Classified as
- Acute - immature cells predominate and divide rapidly (fatal if untreated, prognosis is better - targeting with chemotherapy)
- Chronic - predominance of more mature cells which divide slowly (difficult to treat)
- Lymphocytic
- Non-Lymphocytic
5
Q
What are the causes of leukaemia?
A
- Hereditary factors - fragile chromosomes
- Chromosomes abnormalities e.g. down’s syndrome
- Haematological disease
- Viruses
- Chemical Carcinogens
- Radiation
6
Q
How do you manage leukemia?
A
- Big ICE and G-CSF chemotherapy
- Etoposide - mitotic poison
- Idarubicin
- Cytrarabine
7
Q
Define Neutropoenia
A
- Decrease in absolute neutrophil count
Effects
- Risk of life threatening infection, and ulceration of mouth and GIT, diarrhoea, and skin infections
Treatments
- Isolation to reduce further infections
- Oral care to minimise thrush
- G-CSF to stimulate BM
8
Q
Define Hodgkin’s Lymphoma
A
- Cancer from WBC called lymphocytes
- Swollen but painless lymph nodes
- Presence of giant Reed-Sternberg cells
- Good prognosis compared to Non-Hodgkins
- Well managed by radiation or chemotherapy
9
Q
Define Non-Hodgkins Lymphona
A
- Massive cervical lymphadenopathy
- Weakened immune system
- Different subtypes depending on rate of growth of malignant cells
10
Q
Define Multiple Myeloma
A
- Malignancy involving plasma cells in BM
- 2nd most common blood cancer after Non-Hodgkins Lymphoma
- Oncogene on chromosome 14, higher risk to petrol industry and metal workers
- High number of plasma cells cause increased pressure on bones creating holes and high blood Ca2+
- Blood becomes very viscous due to high concentration of antibodies and Ca2+ which can cause renal damages
11
Q
RBC Structure
A
- maximise Hb content
- faciliates diffusion of gases
12
Q
How does the body handle old RBCs
A
- removed by marcophages in spleen and liver
13
Q
Define Anaemia
A
- Blood is deficient in quality or quantity of Hb
- leads to hypoxia as RBC cannot transport sufficient O2
Causes
- impaired RBC production (bone marrow defect)
- blood loss
- RBC destruction e.g. malaria
14
Q
What the clinical manifestation of anaemia?
A
- Fatigue - insufficient O2
- Cold - reduced peripheral circulation
- Pallor of mucous membranes, conjuctiva and skin
- Tachycardia
- Palpitations
- Dyspnoea
- Dizziness
- Jaundice
15
Q
How does the body respond to Anaemia?
A
- Redistribution of blood to tissues that have a high O2 need
- removal of more O2 by tissues
- Increased HR or SV
- Increased production of RBCs