haematology Flashcards
what is ALL?
acute lymphoblastic leukaemia
This is the malignant proliferation of immature lymphoblasts. It the commonest cause of death in childhood. An arrest in maturation promotes uncontrolled proliferation of immature blast cells, with marrow failure and tissue infiltration.
how does ALL present?
- anaemia
- infection
- bleeding
- hepatosplenomegaly due to infiltration
how is ALL treated?
- CNS direct therapy
- stem cell transplant
what is AML?
AML is the neoplastic proliferation of blast cells derived from marrow myeloid elements. The incidence of AML increases with age and there must be at least 20% blast cells present in the bone marrow for diagnosis.
How is AML diagnosed?
bone marrow biopsy- must be at least 20% blast cells for diagnosis
how is AML treated?
- Chemotherapy
- Supportive measures
- Intensive vs non-intensive approach
- Bone marrow transplant
what can cause microcytic anaemia?
iron-deficiency, anaemia of chronic disease and thalassaemia
what can cause normocytic anaemia?
acute blood loss, anaemia of chronic disease and bone marrow failure
what can cause macrocytic anaemia?
folate deficiency, alcohol excess, hypothyroidism
what can cause iron-deficiency anaemia?
- Blood loos- menorrhagia or GI bleeding
- Poor diet
- Malabsorption- coeliac disease
- Hookworm- very common
how does iron-deficiency anaemia present clinically?
- Can be asymptomatic
- Tiredness, breathless on exertion
- Koilonychia, angular chelitis and glossitis
on a blood film what will iron-deficient RBC appear as?
microcytic hypochromic
what can cause anaemia of chronic disease?
Chronic infection, vasculitis, rheumatoid arthritis, malignancy, renal failure
how do the RBC’s appear in anaemia of chronic disease?
normocytic normochromic
what is sideroblastic anaemia?
acquired or inherited disorder in which the body has enough iron but cannot incorporate it into Hb
what is pernicious anaemia?
lack of parietal and chief cells results in absent intrinsic factor secretion- so less B12 can be absorbed
what can cause pernicious anaemia?
- Autoimmune atrophic gastritis, leading to achlorhydria and lack of gastric IF- B12 malabsorption
- Associated with vitiligo, addisons, hypoparathyroidism, thyroid disease
what can cause folate deficiency?
- Poor diet
- Increased demand- pregnancy/ increased cell turnover
- Malabsorption- coeliac disease
- Alcohol, drugs excess
why do megaloblasts form in a patient with folate deficiency?
B12 and folate are required for DNA synthesis- in the absence of these cells can’t divide
what is haemolytic anaemia?
anaemia caused by the destruction of RBC before their normal life span
what can cause haemolytic anaemia?
- hereditary- G6PD deficiency, pyruvate kinase deficiency
- membrane defects- spherocytosis, elliptocytosis
- haemoglobinopathies- sickle cell disease, thalassaemia
what is aplastic anaemia?
pancytopenia with hypo plastic marrow
what is pancytopenia?
reduced numbers of all major cell lines
what can cause DIC?
DIC= disseminated intravascular coagulation
-Massive action of clotting cascade
-Major initiating factors- release/ expression of tissue factor, or enhanced expression of tissue factor by monocytes
Sepsis
-Major trauma/ tissue destruction- surgery, burns
-Advanced cancer
-Obstetric complications
-Acute promyelocytic leukaemia
clinically how does sickle cell anaemia present?
vaso-occlusive crisis pulmonary hypertension acute chest syndrome splenic sequestration bone marrow aplasia
how is sickle cell anaemia treated?
hydroxycarbamide
prophylatic antibiotics