Kumar and Clark Haematology Flashcards
What are the lifespans of blood cells
RBC= 120
Platelets = 7 days
Granulocytes = 7 hours.
production sites of T and B cells
T= Thymus
B= Bone marrow
Where is Thrombopethin produced ?
kidneys, liver and certain bone marrow stromal cells
What is the use of granulocyte-colony-stimulating factor (G-CSF)?
To accelerate haemopoietic recovery after chemotherapy and haemopoietic cell transplantation
What is the use of erythropoethin ?
It is used to treat anaemia in patients with chronic kidney disease and in patients with certain blood cancers.
What is the use of thrombopoietin receptor agonists such as Romiplostim?
To treat immune thrombocytopenic purpura.
What is RDW?
It s a measure of the variability in size of red blood cells. An elevated RDW suggests increased variation in red cell size – that is, anisocytosis – and this is seen in iron deficiency.
What is ESR?
It is the rate of fall of red cells in a column of blood and is a measure of the acute-phase response.
What does an elevated ESR indicates ?
It reflects an increase in the plasma concentration of large proteins, such as fibrinogen and immunoglobulins. These proteins cause rouleaux formation which causes red cells clumping together and therefore falling more rapidly.
What are CRPs ?
It is a protein produced in the acute-phase response. It is synthesized exclusively in the liver and rises within 6hours of an acute event.
What are the signs of anaemia ?
- Pallor.
- Tachycardia.
- Systolic flow murmur.
- Cardiac failure.
Koilonychia is pathognomonic for what type of anaemia ?
Chronic iron deficiency anaemia.
Jaundice found in what type of anaemia
Hemolytic anaemia
Bone deformities found in what type of anaemia ?
Thalassaemia major
Leg ulcer occur in what type of anaemia ?
Sickle cell anaemia.
What are the peripheral blood investigations in Anaemia ?
- red cell indices
- WCC
- platelet count
- reticulocyte count (as this indicates marrow activity)
- blood film, as abnormal red cell morphology may indicate the diagnosis.
Dry bone marrow tap indicates ?
Myelofibrosis or aplastic anaemia
What are the causes of microcytic hypochromic anaemia?
- Iron deficiency
- defect in globin production such as thalassaemias.
- defect in haem synthesis, termed sideroblastic anaemia.
- Chronic anaemia of chronic disease.
What are the causes of iron deficiency anaemia ?
- blood loss
- increased demands, e.g. growth and pregnancy
- decreased absorption (e.g. post-gastrectomy)
- poor intake.
what are the symptoms of chronic Iron deficiency anaemia ?
- brittle nails
- spoon-shaped nails (koilonychia)
- atrophy of the papillae of the tongue
- angular stomatitis
- brittle hair
- Plummor-Vinson syndrome.
What is the clinical picture of Iron deficiency anaemia ?
MCV <80
MCH < 27 pg
Anisopoikilocytosis
Serum Iron and ferritin decreased
Serum TIBC increased
Iron in marrow and erythroblasts are absent.
Why is ferritin sometimes elevated in Iron deficiency anaemia ?
It is an acute phase reactant. Therefore, it may be elevated in the presence of inflammatory or malignant diseases and also in the presence of liver damage
What is the utility of serum soluble transferrin receptors in anaemia.
The number of transferrin receptors released into the serum from bone marrow erythroblasts increases in iron deficiency. It will help to differentiate between iron deficiency anaemia and anaemia of chronic disease in which it is low.
What is the approximate time it takes to replenish iron stores and low haemoglobin ?
6 moths
What is the pathophysiology of anaemia of chronic disease ?
It is the most common type of anaemia in hospitalised patients and in patients with chronic diseases.
The pathophysiology consist of Low iron release from bone marrow to developing erythroblasts and inadequate EPO response to anaemia + high hepcidin levels -> Low red cell survival > Low TIBC, normal or increased ferritin.
What is a novel marker to differentiate iron deficiency anaemia from anaemia of chronic disease
Serum hepcedin levels as they are normal or decreased in Iron deficiency anaemia and increased i anaemia of chronic disease.
What is the cause of vast majority sedorrhoblastic anaemia in adults ?
primary acquired sideroblastic anaemia: a myelodysplastic syndrome.
acquired causes of sedorrhoblastic anaemia ?
- Isoneazide,
- alcohol
- Led toxicity.
What are the causes of normocytic, normochromic anaemias?
- acute blood loss
- endocrine disorders: hypopituitarism, hypothyroidism and hypoadrenalism.
- haematological disorders: aplastic anaemia and some haemolytic anaemias.
What are Macrocytic Megaloblastic anaemia?
Megaloblastic anaemia is characterized by the presence in the bone marrow of erythroblasts with delayed nuclear maturation because of defective DNA synthesis ( Megaloblasts).
What are the causes Macrocytic Megaloblastic anaemia?
-B12 deficiency or metabolism defects.
- Folic acid deficiency or metabolism defects.
- congenital enzyme deficiencies in DNA synthesis (e.g. orotic aciduria)
- drugs interfering with DNA synthesis: hydroxycarbamide (hydroxyurea), azathioprine
-myelodysplasia due to dyserythropoiesis.
Laboratory findings in Macrocytic Megaloblastic anaemia?
High MCV
Peripheral blood smear shows oval macrocytes + multilobbed polymorphs.
- If severe, there may be leucopenia and thrombocytopenia.
- LDH is typically elevated reflecting ineffective erythropoiesis.
What are the causes of B12 deficiency?
Low dietary intake
* Veganism
Impaired absorption
Stomach
* Pernicious anaemia
* Gastrectomy
* Congenital deficiency of intrinsic factor
Small bowel
* Ileal disease or resection
* Bacterial overgrowth
* Tropical sprue
* Fish tapeworm ( Diphyllobothrium latum )
Abnormal utilization
* Congenital transcobalamin II deficiency
* Nitrous oxide (inactivates B 12 )
What is pernicious anaemia ?
Pernicious anaemia (PA) is an autoimmune disorder in which there is atrophic gastritis with loss of parietal cells in the gastric mucosa and consequent failure of intrinsic factor production and vitamin B 12 malabsorption.
What is the Tx of B12 deficency ?
Hydroxocobalamin 1000 μg can be given intramuscularly to a total of 5–6 mg over the course of 2weeks; 1000 μg is then necessary every 3months for the rest of the patient’s life.
What are the causes Macrocytosis without megaloblastic changes?
- alcohol excess
- liver disease
- reticulocytosis (e.g. due to haemolysis)
- hypothyroidism
- some haematological disorders (e.g. aplastic anaemia, myelodysplasia, pure red cell aplasia, multiple myeloma)
- drugs (e.g. hydroxycarbamide, azathioprine)
- cold agglutinins due to autoagglutination of red cells