Haematology (2) Flashcards
What are the signs of Beta Thalassemia Major and how are they different from Beta Thalassaemia trait?
Beta thalassemia Major:
- Extramedullary haematopoiesis (bone expansion, hepatosplenomegaly, frontal bossing)
- Anaemia: heart failure, growth retardation
- Iron Overolad: heart failure, gonadal failure
Beta thalassemia Trait:
- Asymptomatic
- Microcytosis (normal/low-normal haemoglobin)
Thalassaemia is the direct result of a decreased production of beta-haemoglibin chain (differs from sickle cell which refers to structurally abnormal production)
What are the main investigations for Thalassaemia and what do you expect to find ?
Haemoglobin electrophoresis: GOLD standard
Blood film: microcytic red cells, tear drop cells, target cells, shistocytes, nucleated RBC’s
How does Haemolytic Disease of the Newborn occur and what are the main presentations?
Maternal Anti-D antibodies, which were created during first birth (mother was Rh-, father Rh+, baby Rh+ and mother during dilevery created anti-d antibodies )
Symptoms:
1. Yellow amniotic fluid
2. Hydrops fetalis (with hepatosleponocardiomegaly, since the fetus needed to create new red blood cells)
3. Jaundice 24-36hrs after birth (<2days)
4. Pallor
What is the appropriate prevention to avoid Haemolytic Disease of the Newborn?
What test can indicate the need for more prophylaxis?
You need to provide prophylaxis medication to mother after sensitising event (<72hrs) to stop her from making ani-D antibodies in the future
RhoGAM Suppresses the mother’s immune response and antibody formation against the fetal Rh positive blood cells (fake anti-D antibodies)
Kleiheur test can determine the need for more
How do you manage a baby with Haemolitic Disease of the Newborn (during and after pregnancy?)
Phototherapy (uBR) and IVIG (if bilirubin is rising >8.5 umol/L/hr)
Severe or in utero–> transfusion (O, Rh -ve blood) into umbilical vein–> delivery 37-38w
IVIG: is an examle of competitive inhibition, preventing neonatal eythrocytes from being destroyed
What does G6PDD deficiency entail?
X-linked autosomal recessive condition, where due to the absence of G6PDD from the cell wall there is inbalanced oxidative stress which leads to haemolysis
More common in people from Africa, Mediterranean, Middle east
What causes G6PDD deficiency?
- Anti-malarial drugs (quinine)
- Antibiotics (nitrofurantoin)
- Analgesics (high dose aspirin)
- Fava beans
What are the main symptoms for someone with G6PDD deficiency?
Dark Urine (haemoglobin in urine)
Pain in the back (due to nephrotoxicity)
Jaundice in neonates (<3/7 of life and might require transfussion )
What are the appropriate investigations for G6PDD, what does it show?
What is the management?
- Blood film: Heinz cells and bite cells
- Reduced G6PDD after a haemolytic episode and increased during one (with higher reticulocyte count)
Management: avoid triggers and be aware of the signs of haemolysis
if acute haemolysis then requires supportive care+ folic acid (blood transfusion is rarely required)
What is the aetiology of Gaucher’s disease?
What are the different types and how do they differ?
It is an autosomal recessive condition, most common in Ashkenazi Jew
The enzyme GBA is missing and Glucocerebroside (toxic substance) cannot be broken down, in eaten by macrophages giving them a fatty appearance. Then it accumulates in the bone marrow, liver, spleen and secrete lysosomal enzymes and inflammatory signals.
Type 1: asymptomatic or BM fibrosis, decreased production of RBC’s–> anaemia and fatigue or bone infraction (decreased blood flow, decreased bone crisis)
Type 2: acute with brain involvment (muscle spasm, truoble swallowing–> broblmes breathing and feeding, decreased muscle tone, loss of motor skill)
Type 3: chronic with slowere progression of type 2 symptoms (also seizures)
How does a child with Gaucher syndrome present?
Acute infantile form:
* Hepatosplenomegaly
* Neurological degeneration with seizures
Chronic Infantile form:
* Hepatosplenomegaly
* BM supression (with anaemia)
What are the appropriate investigations for Gaucher Diseae and what is the management?
Investigations:
FBC and blood film
LFTs and clotting
USS of liver and spleen (BM aspirate –>Gaucher cells)
Management:
1. Enzyme replacment therapy (IV recombinant glucocerebrosidade)
2. **Substrate reduction therapy **(which block the enzyme that produced glucocerebroside)
What is the Aetiology of Galactosaemia and what are the presenting symptoms?
Inability to break down milk, which remains in the blood and can built up in liver, kidney, brain and eyes. (deficiency of galactosel phosphate)
Presentation:
- Hepatomegaly
- Hypoglycaemia (ususally picked up in neonatal life)
- Sepsis
- high concentration of Gal-1 phosphate can also lead to bilateral cataracts
- Usually symptoms improve by abstaining from milk
What are the appropriate investigations and Management for Galactosaemia?
Investiations:
1. High Galactose in Urine
2. Red cell Gal-1-PUT
Management: avoid galactose
What are the main types of Glycogen Storage Disease?
Von Gierke’s :
Glucose cannot be liberated from glucose-6-phosphate (G6P builds up inside the cells as G6-phosphotase is used to remove the high-energy phosphate group so the glucose can leave the cell)
McArdle :
Often has muscle cramps / weakness after first few minutes of exercise –> ‘second wind’ of energy
