Paediatric haemotology

Question 1

Haemotological difference between neonates/children/adults

Answer 1

Children can make blood from all bone marrow unlike adults who can only make it in pelvis

Question 2

Childrens RBC

Answer 2

bigger in children
at birth 60% hb is hbF
haematocrit is higher in children =  (vol%) of red blood cells in blood
Hb switching in fetus 
Chr 16--> alpha chains 
Chr 11--> beta chains

Question 3

Childrens WBC

Answer 3

Similar number but higher lymphocyte counts
IgG crosses the placenta. breast milk has igA,D,E,G&M = passive immunity
-produce antibodies from 3 months and satisfactory responses by 12months

Question 4

Childrens Platelets

Answer 4

reach adult numbers by 18 weeks of gestation
initially larger platelets but but same size at birth
hyperrresponsive platelets to vWF but hyporesponsive to some agnoists so balanced out.

Question 5

Haemostasis in children

Answer 5

coagulaiton proteins dont cross the placenta effectively so the umbilical cord doesnt clot.
Only F5,8 & 13 are normal at birth.

Question 6

summary of neonatal haemostasis

Answer 6

procoagulatn proteins refuced: F 2,7,9, 10,11, 12 & prekallikrein
reduced concentration of coagulation inhibitors
raised D dimers and vWF

Question 7

Vitamin K

Answer 7

Factor 2,7,9 & 10 are vit k dependent.
placental gradient means 10% vit K is from mother
hameorrhagic disease of newborn –> bleed to death prevented by routine injeciton of neonatal vit K
mother needs oral vit k. warfarin teratogenic.

Question 8

Congenital causes of anaemia in childhood

Answer 8

• Hameoglobin synthesis problem: haemaglobinopathy
  5% worldwide carry population carry abnormal gene ie thalassaemia.
  -bone marrow failure, infiltration
  -peripheral destruction Rh/abo incompatability or membrane defect ie hereditary sphereocytosis (sphere shaped rbc) and blood loss

Question 9

Acquired causes of anaemia in childhood

Answer 9

• neutritional deficicency i.e b12 folate/iron
• blood loss
• bone marrow failure syndromes
• bone marrow infiltration (Anemia characterized by appearance of immature myeloid and nucleated erythrocytes in the peripheral blood, resulting from infiltration of the bone marrow by foreign or abnormal tissue. )
• Peripheral destruction: heamolysis
• blood loss: i.e twin to twin transfusion

Question 10

Congenital causes of bleeding in neonates/children

Answer 10

Platelet problem
Clotting factor problem
Connective tissue disorder

Question 11

Acquired causes of bleeding in neonates/children

Answer 11

Trauma: accidental, non-accidental
Tumour
Infection: acute eg meningococcus, chronic eg HIV
Immune disorder: primary - immune thrombocytopenia, TTP: secondary - SLE, ALPS
Bone marrow failure
Drug related