Haematology 1 - Acute leukaemia Flashcards
Which cells are affected in the different leukaemias?
AML- can affect ay of the cells in the myeloid lineage
CML- affects pluripotent haemoatopoietic stem cell
- In chronic phase, it is characterised by overproduction of myelocytes
- In acute phase, they can undergo a lymphoblastic transformation (lymphoblastic crisis)
ALL- affects mature T cells or B cells
CLL- affects mature B cells (*T cell is uncommon)
What is the median age of presentation of AML?
65-70
what are the two types of mutation that result in AML?
Type 1: promotes proliferation and survival eg FLT3-ITD
Type 2: blocks differetiation (differentiation is good, and usually followed by apoptosis) eg PML-RARA
Recall some genetic associations of AML
a) translocation: t(15;17) >>> PML-RARA fusion gene >>> APML
b) inversion of chromosome 16
c) trisomies/duplications
- Trisomy 21- Downs or Trisomy 8
d) deletions - 5q deletion
- 7q deletion
Which chromosome abberation causes APML?
WHat are the type 1 and type 2 mutations that cause APML?
Type 1 mutation: FLT3-ITD
Type 2:
- t(15,17)
- Fusion of PML-RARA
Which type of leukaemia is most likely to cause haemorrhage?
Acute Promyelocytic leukaemia (APML)
Which type of leukaemia is most likely to cause DIC + hyperactive fibrinolysis
and what would you see in clotting studies
APML
- Prolonged PT
- Prolonged/short APTT
- Low fibrinogen
What is the key triad of clinical features of AML + ALL
Anaemia
Thrombocytopaenia
Neutropaenia - although high WCC on FBC due to increase of blast cells
How can myeloid lineage be proved on blood film?
Presence of auer rods
*but if you don’t see auer rods you can’t be sure whether its myeloid or lymphoid
hence will need to do further tests
Recall some useful supportive therapies for AML+ ALL
Blood products: red cells, platelets and FFP
Antibiotics: PCP prophylaxis, broad-spec for fever
Long line
Allopurinol (as uric acid may be released from dying cells when treatment is started)
FLuid and electrolytes
Which type of leukaemia is most likely to present with long bone pain?
ALL
Recall some sites of leukaemic involvement in ALL that you wouldnt see in AML
Thymus, testes, CNS, bone pain
lymphadenopathy- less common in AML
Which ALL patients are appropriate for imatinib treatment?
Philadelphia chromosome positive
What is the best technique to differentiate between AML and ALL?
Immunophenotyping
- immunocytochemistry
- immunohistochemistry
This has replaced cytochemistry ((Myeloperoxidase, Sudan Black, Non-specific Esterase) etc..
What is aleukaemic leukaemia?
type of AML
When the leukaemic cells are not in the peripheral blood, they are restricted to the bone marrow