KEY ANAEMIA Flashcards
Define anaemia.
Hb level 2 standard deviations below the normal range for age and sex.
Normal Hb range for men.
130-180.
Normal Hb range for women.
115-165.
5 causes of microcytic anaemia.
IDA Anaemia of chronic disease Thalassemia Sideroblastic anaemia Lead poisoning
5 causes of normocytic anaemia.
Haemorrhage Haemolytic anaemias Leukaemia Pure red cell aplasia Aplastic anaemia
6 causes of macrocytic anaemia.
B12/ folate deficiency. Pregnancy Chronic alcohol misuse Drug induced (methotrexate) Hypothyroidism Myelodysplastic syndromes
MCV for microcytic anaemia?
<80
MCV for normocytic anaemia?
80-100
MCV for macrocytic anaemia?
> 100
How are microcytic anaemias further classified?
Iron studies.
How are normocytic anaemias further classified?
Reticulocyte count.
How are macrocytic anaemias further classified?
Megaloblastic vs. non-megaloblastic.
What can a mixed iron + B12/folate deficiency cause?
A normocytic anaemia (look at RDW to detect).
Iron studies in iron deficiency anaemia?
Low serum iron
Low ferritin
High transferrin/ TIBC
Iron studies in anaemia of chronic disease?
Low/ normal serum iron
Low/ normal ferritin
Low transferrin/ TIBC
Test used to detect Thalassemia?
Mentzer index (MCV/RBC)
<13 = Thalassemia
Causes of normocytic anaemia with <2% reticulocytes.
<2% reticulocytes = hypoproliferative:
Leukaemias
Aplastic anaemia
Pure red cell aplasia
Causes of normocytic anaemia with >2% reticulocytes.
> 2% reticulocytes = hyper proliferative:
Haemolytic anaemias
Haemorrhage
What does megaloblastic mean?
Presence of megalocytes with hyperhsegmented neutrophils.
Causes of megaloblastic macrocytic anaemia.
B12 deficiency
Folate deficiency
Drug-induced (methotrexate)
Causes of non-megaloblastic microcytic anaemia.
Alcohol abuse
Hypothyroidism
Pregnancy
Myelodysplastic syndromes
Where is iron absorbed?
Duodenum
How does iron travel in the blood?
Bound to transferrin.
How is iron stored in the blood?
By ferritin.
Iron studies in sideroblastic anaemia?
High iron
High ferritin
Low transferrin/ TIBC.
4 main categories of cause for iron deficiency anaemia.
Decreased intake
Decreased absorption
Increased loss
Increased demand
Why is it common to get a macrocytic anaemia a couple of days after a GI bleed or traumatic bleed?
Because bone marrow responds by producing large numbers of reticulocytes.
Drugs which can cause macrocytic megaloblastic anaemia.
Methotrexate
Azathioprine
Trimethoprim
Phenytoin
Why does B12 deficiency need to be corrected before folate deficiency?
Giving folate first can cause subacute degeneration of the cord.
Where is B12 absorbed?
Terminal ileum.
Where is Folate absorbed?
Jejunum
Food substances containing B12?
Meat and dairy.
Food substances containing folate?
Green, leafy vegetables
Beta thalassemia inheritance pattern?
Autosomal recessive.§
When does Beta Thalassemia present?
Childhood.
Blood film finding in sideroblastic anaemia?
Ringed sideroblasts (Iron-engorged peri-nuclear mitochondria in developing RBCs).
5 causes of B12 deficiency?
Pernicious anaemia IBD Gastric bypass/ gastrectomy Poor dietary intake Veganism
5 causes of folate deficiency?
Elderly Alcohol dependent Haemolysis Pregnancy Malabsorption Anti-folate drugs (methotrexate)
The only anaemia to cause neurological symptoms?
B12 deficiency
Neurological symptoms of B12 deficiency?
Confusion
Drowsiness
Poor concentration
Poor memory
Patients with pernicious are at an increased risk of what?
Gastric cancer
Pathognomonic blood findings in pernicious anaemia?
Increased IgA antibodies against intrinsic factor/ parietal cells
2 categories of haemolytic anaemia?
INTRAVASCULAR: RBCs broken down in blood vessels.
EXTRAVASCULAR: RBCs broken down in spleen (more common)
3 categories of congenital causes of haemolytic anaemia?
Membrane abnormalities
Metabolic machinery abnormalities
Haemoglobin molecule abnormalities
2 forms of acquired haemolytic anaemia?
Cold autoimmune haemolytic anaemia
Warm autoimmune haemolytic anaemia.
Main cause of haemolytic anaemia caused by membrane abnormalities?
Hereditary spherocytosis.
Findings in hereditary spherocytosis?
Circular cells
Low Hb
Raised reticulocytes
Main cause of haemolytic anaemia resulting due to a metabolic machinery abnormality?
G6PD deficiency.
Inheritance pattern of G6PD deficiency?
X-linked recessive.
Pathognomonic blood film finding in G6PD deficiency?
Heinz bodies.
2 forms of haemolytic anaemia that affect the haemoglobin molecule?
SCD
Thalassemia
Difference between warm and cold AIHA?
Warm occurs at body temperature
Cold occurs in the peripheries at lower temperatures
3 conditions warm AIHA is associated with?
CLL
Lymphoma
SLE
Warm AIHA is mainly caused by which antibodies?
IgG.
3 conditions cold AIHA is associated with?
Mycoplasma pneumonia
Infectious mononucleosis
Lymphomas
Cold AIHA is mainly caused by which antibodies?
IgM
Non-immune causes of acquired haemolytic anaemia?
Mechanical trauma
Infections
Hypersplenism
Urinary finding in those with haemolytic anaemia?
Haemosiderinuria
Test for autoimmune haemolytic anaemia?
Direct Coombs test
How is acute chest syndrome in those with SCA diagnosed?
Fever or respiratory symptoms + presence of infiltrates on XR.
Most common cause of osteomyelitis in those with SCA?
Salmonella.
Classic triad of haemochromatosis?
DM
Bronze skin
Hepatomegaly
Management for haemochromatosis?
Venesection
Prophylaxis for what condition can trigger haemolytic anaemia in those with G6PD deficiency?
Malaria.
RBC transfusion cut off in anaemia?
<60
RBC transfusion cut off in those who are anaemic with an ACS?
<80
