Red Cells Continued Flashcards
What does PNH stand for?
Paroxysmal nocturnal haemoglobinuria
What is PNH?
Acquired disorder leading to haemolysis (mainly intravascular) of haematological cells
Pathology of PNH
Increased sensitivity to the cell membranes of complement due to the lack of GPI
What are patients with PNH more prone to?
Thrombosis
Presentation of PNH
Haemolytic anaemia May have pancytopenia Haemoglobinuria Thrombosis e.g. Budd chiari syndrome Some patients may develop aplastic anaemia
What is haemoglobinuria?
Classically dark coloured urine in the morning
Can occur throughout the day
Investigation of PNH
Hams test
What is hams test?
Acid induced haemolysis (normal red cells would not)
Treatment of PNH
Blood product replacement
Anticoagulation
Stem cell transplant
What is the most common cause of haemolytic anaemia in patients with G6PD deficiency?
Ciprofloxacin
Who with sickle cell anaemia should have a low threshold for hospital admission?
In a child
Person with temp over 38C (risk of rapid deterioration)
Person with chest symptoms (as acute chest syndrome may develop quickly)
Investigation for hereditary spherocytosis
EMA binding test
When does intravascular haemolysis occur?
RBCs rupture in the vessel and are bound to haptoglobin to be excreted in the urine
When does extravascular haemolysis occur?
Phagocytosis of RBCs
What systemic disease is a cause of autoimmune haemolytic anaemia?
SLE
How long does oral iron tablets take to work?
2 - 4 weeks
How long does it take for oral iron tablets to change blood results?
2 - 3 months
What is mixed anaemia and what may it present as?
Both vit B12 and iron deficiency anaemias
Normocytic anaemia
What crises are recognised with sickle cell disease?
Chest crisis Thrombotic 'painful' crisis Sequestration Aplastic Haemolytic
Thrombotic crisis is also known as what?
Painful crisis
Vaso-occlusive crisis
What is thrombotic crisis precipitated by?
Infection
Dehydration
Deoxygenation
Features of thrombotic crisis
Infarcts occur in various organs including
- Bones (e.g. avascular necrosis of the hip)
- hand foot syndrome in children
- lung
- spleen
- brain
Explain sequestration crisis
Sickling within organs such as the spleen or the lungs, causing pooling of blood with the worsening of anaemia
Increased reticulocytes
What is the most common cause of death in sickle cell disease after childhood?
Acute chest crisis
What is aplastic crisis caused by?
Infection with parovirus
What does aplastic crisis cause?
Sudden fall in Hb
Reduced reticulocytes
Pathology of haemolytic crisis
Fall in Hb due to an increased rate in haemolysis
How often do sickle cell patients receive a pneumococcal vaccine?
Every 5 years
What type of diet is a risk factor for B12 deficiency?
Vegan
What anaemia does sickle cell disease cause?
Normocytic with increased retics
Explain hand foot syndrome in children
Sickling of RBCs interfering with the circulation in the hands and feet
Results in swelling, pain and erythema with a sudden onset
Sickle cell disease
What symptom would point towards splenomegaly?
“Stomach fullness”
In all people with iron deficiency anaemia, what should they be screened for?
Coeliac disease
What does a disproportionally low microcytic anaemia indicate?
Beta-thalassaemia trait
What can parovirus precipitate if you have hereditary spherocytosis?
Haemolytic crisis
