Related Subjects:
|Leukaemias in General
|Acute Promyelocytic Leukaemia
|Acute Myeloblastic Leukaemia (AML)
|Acute Lymphoblastic Leukaemia (ALL)
|Chronic Lymphocytic leukaemia (CLL)
|Chronic Myeloid Leukaemia (CML)
|Hairy Cell Leukaemia
|Differentiation syndrome
|Tretinoin (All-trans-retinoic acid (ATRA) )
|Haemolytic anaemia
|Immune(Idiopathic) Thrombocytopenic Purpura (ITP)
Give all-trans-retinoic acid (ATRA), stimulates
the cells to resume differentiation. Know Translocation t(15;17)
About
- A form of AML with a predisposition to DIC
- It can be treated with all trans retinoic acid (ATRA)
- ATRA allows the further differentiation of promyelocytes
- APML may cause DIC which can worsen with therapy
Aetiology
- AML is due to the formation of clonal proliferation of myeloid precursors with reduced capacity to differentiate into more mature cellular elements.
- The increased production of malignant cells, along with a reduction in these mature elements, result in a variety of systemic symptoms, anaemia, bleeding, and an increased risk of infection.
- There is a translocation between chromosomes t(15;17) translocation
- The gene on chromosome 17 codes for retinoic acid receptor alpha - RARa
- The gene on chromosome 15 is the promyelocytic gene (PML gene)
- PML-RARa fusion has reduced sensitivity to retinoic acid which blocks differentiation of myeloid cells
Auer rods in APML
Clinical
- Fatigue and weight loss. Anorexia. Evidence of infection or hemorrhage
- Marrow failure with anaemia, low platelets and abnormal WCC
- Severe bleeding, associated with Disseminated Intravascular Coagulation which may occur or be precipitated by cytotoxic treatment
Investigations
- FBC : anaemia, low platelets, high WCC
- Leukaemic forms in the bone marrow, peripheral blood, and other tissues
- Abundance of promyelocytes with Auer rods found
- Marked Low red cells, platelets, WBC (neutrophils) count
- Low fibrinogen, Coagulopathy
Management(See treatment of AML)
- Treat with chemotherapy + ATRA, FFP, Keep platelets > 30-50
- The differentiation can be improved with all trans retinoic acid (ATRA)
- This is a vitamin A derivative that can cause clinical remission.
- The drug allows the neutrophils to continue to develop to maturation.
- Coagulopathy - give platelets, fibrinogen, ATRA
Retinoic acid syndrome.
- Retinoic acid syndrome from ATRA is usually < 3 weeks of treatment.
- Chest pain, fever, and dyspnea. Hypoxia is common
- CXR: diffuse alveolar infiltrates with pleural effusions. Pericardial effusions
- Release of cytokines. Mortality of retinoic acid syndrome is 10%.
- High dose
glucocorticoid therapy is usually effective in treatment