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Flashcards in Haematological Disorders Deck (139)
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When is HbF very low in healthy children - when is it not?

By age 1
Increased proportions of HbF are indicators of severe inherited disorders of haemoglobin production - haemoglobinopathies


Hb at birth

14-21.5g/dl to compensate for low oxygen concentration in fetus


What happens to Hb after birth

Falls over first few weeks of life, mainly due to reduced red cell production, to 10g/dl at 2 months of age


What happens to Hb after birth in pre-term babies?

It has a steaper fall to a mean of 6.5-9g/dl at 4-8 weeks chronological age


What are the iron, B12 and folic acid stores like in term and preterm infants at birth and after birth?

Iron, B12 and folic acid are adequate at birth in term and preterm babies
However in preterm babies stores of iron and folic acid are lower and are depleted more quickly leading to deficiency after 2-4months if recommended daily intakes are not maintained by supplements


Anaemia value in neonate

Hb less than 14g/dl


Anaemia value in 1-12months old

Hb less than 10g/dl


Anaemia value in 1-12 years

Hb less than 11g/dl


What is red cell aplasia

Complete absence of red cell production


What is ineffective erythropoeisis?

Red cell production is normal/increased rate but differentiation or survival of red cells is defective


What are the main causes of iron deficiency anaemia x3

Inadequate intake (common in infants)
Blood loss


Which milk is not good for maintaining infant iron levels?

Cows milk because it has a higher iron content than breast milk but only 10% of the iron is absorbed
Therefore infants should not be fed unmodified cows milk


At what Hb level do children become symptomatic with anaemia?



How do children with iron deficiency anaemia present?

Pica- eating non-food materials such as soil, chalk, gravel or foam rubber


What are indicators on blood tests of iron deficiency anaemia

Microcytic, hypochromic anaemia (low MCV and MCH)
Low serum ferritin


Management of iron deficiency anaemia in infants?

Increase oral iron intake with supplementation - Sytron or Niferex are best tolerated preparations
Or just increase iron rich foods


What are the 3 main causes of red cell aplasia in children?

1) Diamond-Blackfan anaemia - congenital red cell aplasia
2) Transient erythroblastopenia of childhood
3) Parvovirus B19 infection in children with haemolytic anaemia


Diagnostic features of red cell aplasia x4

Low reticulocyte count despite normal Hb
Normal bilirubin
Negative direct antiglobulin/Coombs test
Absent red cell precursors on bone marrow examination


What is Diamond-Blackfan anaemia?

It is a rare congenital disease of red cell aplasia


Inheritance of Diamond-Blackfan anaemia

20% family history - remaining 80% are sporadic mutations
RPS (ribosomal protein) genes implicated in some cases


Presentation of Diamond-Blackfan anaemia

Most present at 2-3 months of age but 25% present at birth


Features of Diamond-Blackfan anaemia x2

Also congenital abnormalities such as short stature or abnormal thumbs


Treatment of Diamond-Blackfan anaemia x2

Oral steroids
Monthly red cell transfusions for children not responsive to steroids


What is transient erythoblastopenia of childhood?

Red cell aplasia usually triggered by viral infections
Same haemotological features as D-Blackfan anaemia


Prognosis of transient erythroblastopenia of childhood

Always recovers - usually within several weeks (hence differs from d-blackfan)


Inheritance of transient erythroblastopenia of childhood

No family history


When does haemolysis lead to anaemia?

When the bone marrow can no longer increase red cell production to compensate for the premature destruction of red cells


Main causes of haemolytic anaemias in children? What is uncommon children

Intrinsic abnormalities of RBCs (membrane and enzyme disorders and haemoglobinopathies)
Immune haemolysis is uncommon


What does haemolysis from increased RBC breakdown lead to? x4

Hepatomegaly and splenomegaly
Increased blood levels of unconjugated bilirubin
Increased urinary urobilinogen


Diagnostic clues to haemolytic anaemia x4

Increased reticulocyte count
Unconjugated bilirubinaemia and urinary urobilinogen
Abnormal appearance of red blood cells on film (spherocytes, sickle shaped or very hypochromic)
Increased red blood cell precursors in bone marrow