Paediatric haemotology Flashcards
what is the structure of foetal haemoglobin
2 alpha chains
2 gamma chains
haematopoiesis- where does it start in a fetes and where does it end up in an adult
o Initially yolk sac until 2..5 months, then stops
o Liver- 1 month peaks at 4/5 months
o Spleen makes RBC again at 1 month and stops 7 months
o Bone marrow makes RBC by birth
If you have a problem with you bone marrow which 2 organs take of the haematopoiesis function
spleen and liver.
when does haemoglobin with take place from foetal to adult
at birth.
chromosome 16 gives rise to which globulin chains
alpha, zeta
chromosome 11 gives rise to which globulin chains
gamma, beta, delta, epsilon
what chains does HB gower consist of.
zeta/epsilon
what chains does Hb portalnd consist of.
zeta/gamma
which immunglobulin crosses the placenta
IgG
breast milk contains which antibodies
Ig A, IgD, IgE, IgG, IgM
Are the WBC, same, lower or higher in children in comparison to adults
same.
at what age can you make a satisfactory immune response
6 months.
at what age do you start producing your own antibodies
2 to 3 months.
Are platelets the same, lower or higher in children in comparison to adults.
higher
Birth is a bloody process to develop platelets to prevent affects of haemorrhage.
what clotting cascade factors are normal at birth.
Only fibrinogen, FV, FVIII, FXIII
at what age do all haemostatic (clotting cascade) parameters each normal.
by 6 months
Is Vitamin K level the same, lower or higher in newborns
foetal vitamin K is 10% mother
what is done in order to make sure that neonates are not vitamin K dependent
given a dose of vitamin K at birth.
what blood thinner is teratogenic
warfarin
what drug use exacerbates vitamin K deficiency
anti-convulsants.
what factors are vitamin k dependent
2,7,9,10, protein C, protein S.
what are the congenital causes of anaemia in childhood
- Haemoglobin synthesis problem- haemoglobinopathy
- Bone marrow failure syndrome.
- Bone marrow infiltration- storage disorders.
- Peripheral destruction
- Blood- losing blood.
name 2 common haemoglobinopathies
- Thalassemia- cell look random shape and sizes.
* Sickle cell disease- (irreversible sickle cell)- not flexible and clog up blood vessel.
how are haemoglobinoptathies diagnosed before the childs birth.
antenatal screening
main causes of peripheral destruction blood disorders
- Rh/ABO or other incompatibility
- Membrane defect: hereditary spherocytosis (haemoglobin pressed into a dense compact manner causing them to be brittle)
- Enzyme defect G6PD deficiency, PK deficiency
- Infection.
which more prevelanet prenatally ABO or Rh incompatibility and why
o ABO incompatibility- make IgM which cannot cross placenta, ABO on RBC after birth, not common prenatally.
o Rh- has significant effects prenatally.
what is the prenatal treatment for Rh incompatibility
Given anti-D prophylaxis, so it removes antibodies that the mother develops.
what causes acquired childhood anaemias
- Nutritional deficiency: iron (common in 2-4 yrs old- due to milk based diet), B12 (rare), folate (very rare).
- Bone marrow failure- Aplastic anaemia- idiopathic or liver disease associated.
- Bone marrow infiltration- stops anything else from happen in in the bone marrow.
- Peripheral destruction: haemolysis
- Blood loss.
congential bleeding problems
- Platelet problems- most common, low platelet due to mothers taking medicines e.g for ITP, gestational thrombocytopenia.
- Clotting factor e.g. circumcision
- Connective tissue disorder.
acquired bleeding problems
• Trauma: accidental, non accidental
• Tumour e.g. leukaemia, can cause bleeding.
• Infection: acute eg meningococcus (treatment platelets), chronic eg HIV
• Immune disorder primary- immune thrombocytopenia, TTP (similar symptoms to meningioccous)
Secondary-SLE, ALPS (Autoimmune lymphoproliferative syndrome- range of autoimmune conditions- difficult to mamage)
• Bone marrow failure
• Drug related.
