Haematological lecture Flashcards
What are the three main functions of blood?
- Regulation
- Transportation
- Protection.
What are the main components of blood?
1- Plasma (extracellular matrix that contains dissolved substances)
2- formed elements (cells and fragments) - WBCs RBCs and platelets.
What is the function of RBC, WBC and Platelets
- RBCs - carry the o2 via haemoglobin
- WBCs - fight infection (2 main types; neutrophils and lymphocytes
- Platelets are for clotting and preventing/stopping bleeding.
What is haematopoiesis?
- Process of creating blood cells
- all blood cells come from step cells in the bone marrow.
What is leukaemia?
- neoplastic proliferation of WBCs
What is the function of different WBCs?
monocyte - mobile and phagocytic
lymphocyte - t-cell, immunity
granulocyte - neutrophil, protects against foreign material
What are the 3 types of haematological malignancies?
- leukamia
- polycythemia rubra vera
- multiple myeloma
How is leukaemia characterised?
- Leukaemia cells take up all of the space in the marrow so no room left for normal cells to grow
What are the four types of leukaemia and what groups do they affect?
ALL - Acute Lymphoblastic Leukaemia
- occurs mainly in children/ rarely in adults
- develops quickly/ appears suddenly
AML - Acute Myeloid Leukaemia
- occurs mainly in adults although can occur in children and adolescents
CLL - Chronic Lymphocytic Leukaemia
- Occurs in adults, does not occur in children
CML - Chronic Myeloid Leukaemia
- Occurs at any age but rare >20yo
- appears gradually and develops slowly.
What is ALL? + Pathology
- Occurs mainly in children, rarely in adults
- too many stem cells become lymphocytes = infection, easy bleeding and anaemia.
Pathology = increased number of immature lymphoblasts in the reticular-endothelial system.
What are the risk factors for ALL?
- DOWN SYNDROME
- Environmental exposure to benzene
- Mother smoked marijuna/ was exposed to benzene during pregnancy
- young age
- some viral causes
- blooms syndrome (causes chromosome breakage)
- rad exposure as a child – ionising rad is leukomongic
What are the signs and symptoms of ALL?
- shortness of breath
- weight loss
- fever due to infection
- bone marrow failure leading to leucopenia and thrombocytopenia which case bruising and infection
- splenomegaly
- palpable liver
- petechiae
- peripheral lymphadeneopathy.
a child will generally present:
- pale
- few weeks of malaise
- tender bones esp. over sternum
- bone pain particularly in the long bone
- could be menenigeal involvement leading to headaches, stiff neck and vomiting and vomiting
- haemorrhages in the eye
- mucosal ulceration and gingivitis.
What are some of the adverse prognostic indicators for ALL?
- Philadelphia chromosome present
- T-cell phenotype
- CNS involvement at presentation
- testicular relapse
- adverse cytogenic markers
- early marrow relapse
- WBC count >20000
- if it spreads to the spinal cord or the brain
- whether it is a relapse that is being treated.
What are some of the clinical investigations that can be done for ALL? (8)
- clinical examination – get pts history and look for anything unusual
- cytogenic analysis – look for abnormalities in chromosomes using bone marrow/ blood samples. e.g. the Philadelphia chromosome.
- Blood count - looking at the counts of everything
- Peripheral blood smear - look for the presence of blast cells, platelets, and changes in the shape of WBCs.
- Liver examination
- Immunophenotyping
- radiography
- Bone marrow aspiration or biopsy - a needle is inserted through the hip/pelvic bones from skin to marrow and a small sample of bone marrow is taken. Done under general anaesthesia in the ward, takes 15mins. Looks for anything abnormal. Sometimes need a core of Bone marrow (trephine biopsy).
What staging system is used for ALL?
- No specific staging system used.
What is AML characterised by?
- Occurs in mainly adults can occur in younger people but rare under 20.
- over production of white blood cells called myeoblasts / leukaemic blasts.
- thought to be associated with damage to the chromosome that cause blood development.
What are the risk factors for AML?
- No links to environmental agents
- those who have had rad exposure and some chemos
- downs syndrome
- pts who have some specific blood disorders e.g. myodisplastic syndrome
- CHROMOSOMAL ABNORMALITIES
What are the signs and symptoms (aetiology) of AML?
- infection
- decreased platelet count/ healthy WBC/ RBC
- anemia causing them to feel tired and look pale
- bone marrow failure (lc)
- malaise
- UNUSUAL BLEEDING AND BRUISING
- ACHING BONES AND JOINTS
- bone pain (lc)
- leukostasis (lc)
What are some of the clinical investigations done for AML?
- Radiography to see the extent of infection
- clinical examination
- CHROMOSOME ANALYSIS
- BIOCHEMISTRY – shows abnormal liver function
- full blood count
What is the classification used for AML?
-FAB (French-American-British)
What are the characteristics of CML?
- common in adults, rare >20
- excess amount of granulocytes
- chronic period of 2-4 years, acute period of 3-9 months
What is the only cure for CML?
- Stem cell transplant
CML risk factors
- unknown
- Philadelphia chromosome in most cases
- some cases due to exposure to ionising radiation
CML signs and symptoms
- splenomegaly
- ITCHING
- lymphadectomy
- increased WBC count
- womens periods become heavier
- weight loss
- petechiae
- bone pain
- fevers
- UNUSUAL EXCESSVE BLEEDING
What are some investigations that may be done for CM
- ultrasound to confirm hepatomegaly and splenomegaly
- bone marrow biopsy/ aspiration – show BCR - ABL gene
- blood cell count
What are the three phases of CML?
chronic phase
- tx usually performed as outpatient who has regular blood tests
- rarely symptoms
- usually lasts 4-5 years
- disease progresses slowly
accelerated phase
- disease accelerates
- inpatient
- increased symptoms
- not everyone goes through this phase
- patient will become very tired
- increase in the number of blast cells
blast phase
- disease becomes more like acute leukaemia
- increase in the blast cells (much of the bone marrow replaced by these)
- blast crisis = enlarged spleen, increased temp and fevers
- myelofibrosis = doesn’t occur in every patient but due to fibrosis bone marrow can’t produce new cells.
For CML what is considered remission and what is complete remission
revision - when the number of blast cells returns to normal.
complete remission - philideliphia chromosome not found by even the most sensitive test. (PCR test)
What characterises CLL?
Chronic lymphocytic leukaemia
- damage to dna causing uncontrolled growth and production of B lymphocytic cells.
- important distinction from ALL is that it doesn’t impede the production of blood when it accumulates in the marrow as much.
What are the risk factors for ALL?
- NOT associated with radiation exposure like the rest of them
- maybe fam history
- not really known though
What are the signs and symptoms of ALL?
- peripheral lymphadenopathy
- splenomegaly
- hepatomegaly
- anemia
- RECURRANT INFECTIONS OF THE KIDNEY AND SKIN
- fever
- sweats
- weight loss
Investigations
- Immunophenotyping
- Bone marrow biopsy to show excess lymphoid cells
- blood count
What is the prognosis for CLL?
- remission easily achieved but pts never really cured.
- pt can live many years in remission
What is hairy cell leukaemia?
- over production of b-lymphocytic cells with hair like projections.
- these cells get caught in the spleen causing it to become enlarged, which also further worsens conditions like anaemia etc.
- don’t know why it happens
- predominantly occurs in 40-60yo
- develops slowly and may not cause signs and symptoms for a long time.
How is multiple myeloma characterised?
- increased production of immature abnormal plasma cells and monoclonal immunoglobins.
What are the risk factors in multiple myeloma
- race
- increasing age
- BRACA 1 / 2 gene
- rad exposure
What are the signs and symptoms for multiple myeloma?
- depends on how far the immunoglobin involved
- pts can be assymtomatic for years
- diffuse bone = major complaint
- skeletal abnormalities - leads to pathological fractures and vertebral crush
- weakness and fatigue
- anorexia and weight loss
- anemia
- hypercalcemia
- paraprotein = leads to renal failure
