Week 1 - Day 3 - Pediatric anaemia - Iron deficiency anaemia, Thalassemia/Sideroblastic anaemia, Hereditary spherocytosis

Question 1

Scenario 1

A 1 year old boy, breast fed from birth is noted to be pale at the GP surgery. Mum and Dad are vegans and wish the child to be brought up to enjoy a similar diet. Blood results are: :

• Hb 70 g/L
• MCV 60 fl
• WBC 6 x 109/l (4.0-11.0 x10^9/L )
• Platelets 550 x 109/l (150-400 x10^9/L)
• Ferritin 5 µg/l - (30-400 ug/L)

 Identify the abnormalities from the laboratory tests.

Answer 1

Hb levels in the boy are low (less than 130g/L in males)
The mean cell volume is low in this child (less than 80fl)

WBC count normal
Platelets are high

Serum ferritin is low - this shows iron stores are low

The blood results shows the patient is likely to have hypochormic microcytic anaemia due to iron deficiency

Question 2

A 1 year old boy, breast fed from birth is noted to be pale at the GP surgery. Mum and Dad are vegans and wish the child to be brought up to enjoy a similar diet. Blood results are: :

• Hb 70 g/L
• MCV 60 fl
• WBC 6 x 109/l (4.0-11.0 x10^9/L )
• Platelets 550 x 109/l (150-400 x10^9/L)
• Ferritin 5 µg/l - (30-400 ug/L) What are the likely underlying pathophysiological mechanisms producing these abnormalities in Hb, MCV and ferritin?

Answer 2

It is likely that the child is iron deficient from the diet -
Iron is a main constituent of the haem portion of haemoglobin - if there is a low iron, then there is problem with haemoglobinisation - this means that there isnt enough hamegolobin in the cells (Hb is a major contributer to the MCV) and therefore not enough oxygen can be held (cells are pale) (low Hb, low MCV, low MCH)
As not enough iron, there wont be enough iron stores and therefore the ferritin levels are low

Question 3

Why would the platelet levels be risen in the child with IDA?

Answer 3

This is because in response to the tissue hypoxia - the interstitial fibroblasts of the kidneys will produce erythropoeitin to stimulate eryhtopoeisis to try and produce more red blood cells (EPO is though to act on both red blood cell and platelet precursors however causing a rise in the platelets level), RBC would be decreased as the iron body stores are too low to support normal red blood cell production

Question 4

What are different differentials for the boy?

Answer 4

Iron deficiency anaemia

Thalassemia - alpha/beta thal trait - both are usually asymptomatic

Question 5

If iron deficiency anaemia
 How would you treat this anaemia and what would be the mechanism of action of this treatment.

What ae side effects?

Answer 5

Treat with oral iron supplements - ferrous fumurate or sulphate
This provides the body with iron to therefore replenish the iron stores to make normal Hb (returns ferritin and Hb to normal and MCV to normal)

Side effects - constipation, black stools, nausea, abdo discomfort

Question 6

If correcting the iron deficiency and Hb normalises, then Ida is the cause

At what rate should the Hb pick up?

If it does not normalise, what do you then start to think?

Answer 6

When on treatment for IDA, Hb should rise by 10g/L per week
Continue treatment until Hb returns to normal and then for 3 months to replenish iron stores

If the Hb does not normalise, then consider thalassemia (if after correcting the problem with the haem synthesis, the problem could be with globin synthesis) or sideroblastic anaemia (this could be the other cause of problem with the haem synthesis - iron deifiency could be masking that they have this as a cause)

Question 7

How would you look for thalassemia or sideroblastic anaemia?

Answer 7

Measure the different haemoglobin levels for thalassemia

Blood film for sideroblastic anaemia - expect to see sideroblasts

Question 8

Scenario 2
A 6 month old baby is brought from India by its parents. The child is noted to be very pale and lethargic and is failing to thrive. Two brothers have died from “anaemia” within 6 months of birth. The child apparently drinks bottled baby food and has normal stools.
Following blood results:

• Hb 70 g/L, MCV 60 fl , WBC 6 x 109/l
• Platelets 350 x 109/l , Ferritin 550 µg/l

 Identify the abnormalities from the laboratory tests.

Answer 8

Hb is low
MCV is low

WBC is normal
Platelets are normal
Ferritin is normal/high in this age range

Microcytic anaemia with normal iron is shown - so iron defiency aenami is not shown to be the cause

Question 9

What is the normal platelet level?

State other causes of microcytic anaemia other than iron?

Answer 9

Normal platelet level - 150-400x10^9/L

Thalassemia

Sideroblastic anaemia - pyrodoxine repsonsive anaemia
Anaemia of conic disease

Question 10

A 6 month old baby is brought from India by its parents. The child is noted to be very pale and lethargic and is failing to thrive. Two brothers have died from “anaemia” within 6 months of birth. The child apparently drinks bottled baby food and has normal stools.
Remember microcytic with normal ferrtin

What is the likely cause of the babies anemia?

Answer 10

Thalassemia - two brothers died within 6 months of birth
Beta-thalassemia major

Sideroblastic anaemia - due to problems with haem molecule (ALA synthase enzyme mutation)

Question 11

 Which further laboratory investigations are necessary and explain what pathophysiological mechanisms they are measuring?

What will be seen on haemoglobin studies in beta thalassemia major, intermedia and minor?

Answer 11

Thalassemia - if major
Carry out haemoglobin studies

HPLC

• Major - will have minimal to no HbA, very HbF and variable HbA2
• Intermedia - some HbA - elevated HbF and some A2
• Minor - mostly HbA - elevated HbA2 >3.5% % raised HbF often

Sideroblastic anaemia - if Hb studies come back normal - can do a bone marrow aspirate under Prussian blue stain

Question 12

 How would you treat this anaemia and what would be the mechanism of action of this treatment.
Saying it is beta thalassemia major
Saying it was sideroblastic anaemia

Answer 12

Beta thalassemia major
Repeated transfusion - hopes to suppress ineffective erythropoiesis and replenish O2/iron
Need iron chelating agaent - eg desferasirox

Sideroblastic anaemia - give pyridoxine - vitamin B6

Can give tranfusions if required

Question 13

Scenario 3
A 7-year-old girl has a history of intermittent jaundice and fatigue, usually occurring just after she has had a cold. Her Dad had a splenectomy as a child. Her laboratory results are as follows:

• Hb 90 g/L MCV 85 fl
• WBC 6 x 109/l Platelets 550 x 109/l
• Bilirubin 50 µmol/l Blood film shows spherocytes

 Identify the abnormalities from the laboratory tests.

Answer 13

Hb is low
WBC is normal
MCV is normal

Bilirubin is raised

Platelets are raised

Spherecoytes are abnormal - caused by spleen damaging the red blood cells

Patient has a normocytic anaemia with thrombocytosis and hyperbilirubinaemia

Question 14

• Child is breaking down her red blood cells too quickly and haemoglobin is low
• EPO levels increasing causing platelets to increase in their attempt to correct levels

Could measure reticulocytes to measure bone marrow compensation - compensation fails when she has a cold

WHat is causing the shperoctye production? (Basically asking for differntials)

Answer 14

G6PD deficiency - this would result in increased haemolysis but not any abnromality in red cell shape so no spherocytes

Hereditary spherocytosis - there is an abnormality in the proteins of the red cell membrane preventing the proteins from changing shape - this therefore resulting in spherical shaped rather than biconcave shaped RBCs

Autoimmune hameolytic anaemia

Question 15

What is the treatment of hereditary spherocytosis?

Remember there is a huge increase icnreased RBC turnover here

Answer 15

Treatment - blood transfusions and supportivve care until probably splenectomy at age 5 if condition cannot be controlled

Folic acid supplmentation also due to increased RBC using up the folate stores