Leukaemia - Acute Myeloid Leukaemia Flashcards
Leukaemia definition
WBC/progenitors lose ability to differentiate but maintain ability to replicate
= neoplastic proliferation of WBC (myeloblast/lymphoblast)
= decreased production of other haematopoietic cells therefore functional pancytopenia
= Sx generally = BM failure = bone pain, bleeding, infections, anaemia + TATT
Epidemiology
~ 75 years
Uncommon before 45
Associated with Down Syndrome
RAPID PROGRESSION IF NO Tx ASAP - 3 yr survival = 20% = v.severe
Risk factors
Myelodysplastic syndromes
Previous chemotherapy or radiation exposure
Benzene exposure: painters, petroleum, rubber manufacturers
Aetiology
t(15:17) genetic mutation in one of the precursor cells in bone marrow = excessive production of single cell line
Pathophysiology
Proliferation of myeloblasts and MOST COMMON acute leukaemia in adults
(myeloblasts usually become neutrophils, eosinophil’s, and basophils)
Excessive production of one type of cell can lead to suppression of other cell lines = PANCYTOPENIA
AML + DIC = common subtype = acute promyelocytic leukaemia
Eventual bone marrow failure
Myeloblasts contain crystal aggregates of myeloperoxidase referred to as AURER RODS
Signs
GUM INFILTRATION
Pallor
Lymphadenopathy
Hepatosplenomegaly
Symptoms
Fatigue
Loss of appetite
Bruising + mucosal bleeding due to thrombocytopenia
Weight loss
Fever
Recurrent infections
Diagnosis
FIRST LINE = FBC + Blood film:
- pancytopenia
- myeloperoxidase +ve and AURER RODS
- abnormal leukaemic blast cells
GOLD STANDARD = BM biopsy >20% myeloblasts
Clotting screen: DIC associated with acute promyelocytic leukaemia
Cytogenic testing: t(15:17)
Treatment
FIRST LINE = CYTARABINE + DAUNORUBICIN
+ All-trans retinoic acid (ATRA) - if acute promyelocytic leukaemia
ALLOPURINOL to prevent tumour lysis syndrome
Abx
LAST RESORT = BM transplant
Complications
Tumour lysis syndrome
DIC
Myelosuppression and neutropaenic sepsis
