Leukaemia, Acute Myeloblastic (AML)

Question 1

Define

Answer 1

DEFINITION: malignancy of primitive myeloid lineage white blood cells (myeloblasts) with proliferation in the bone marrow and blood

Classified using the FAB (French-American-British) System into EIGHT morphological variants

Question 2

Causes

Answer 2

Myeloblasts undergo malignant transformation and proliferation

This leads to replacement of normal marrow and bone marrow failure

Question 3

Epidemiology

Answer 3

MOST COMMON acute leukaemia in ADULTS

Incidence INCREASES with age

Question 4

Symptoms

Answer 4

Symptoms of Bone Marrow Failure:

• Anaemia (lethargy, dyspnoea)
• Bleeding (due to thrombocytopaenia or DIC)
• Opportunistic or recurrent infections

Symptoms of Tissue Infiltration:

• Gum swelling or bleeding
• CNS involvement (headaches, nausea, diplopia)

Question 5

Signs

Answer 5

Signs of Bone Marrow Failure:

• Pallor
• Cardiac flow murmur
• Ecchymosis
• Bleeding
• Opportunistic or recurrent infections (e.g. fever, mouth ulcers, skin infections)

Signs of Tissue Infiltration:

• Skin rashes
• Gum hypertrophy
• Deposit of leukaemic blasts in the eye, tongue and bone (RARE)

Question 6

Investigations

Answer 6

Bloods

• FBC - low Hb, low platelets, variable WCC
• High uric acid
• High LDH
• Clotting studies, fibrinogen and D-dimers (to check for DIC)

Blood Film

• Myeloblasts

Bone Marrow Aspirate or Biopsy

• Hypercellular with > 20% blasts

Immunophenotyping

• Antibodies against surface antigens used to classify the lineage of the abnormal clones

Cytogenetics

Immunocytochemistry