Paediatric haematology

Question 1

Important haematological conditions in children

Answer 1

Iron deficiency anaemia. Acute lymphoblastic leukaemia (ALL)
Sickle cell disease. Thalassaemia
Immune/idiopathic thrombocytopenic purpura (ITP). Haemophilia A

Question 2

Definition of anaemia

Answer 2

A reduction of Hb below the normal range

Adult male - if <160g/L

Question 3

Causes of anaemia

Answer 3

Failure of production (reticulocytes will be low)

Excessive loss from bleeding or haemolysis (reticulocytes high or normal)

Question 4

Iron deficiency

Answer 4

Adults need 1mg/day iron — absorbed through duodenum
Depletion of iron stores (low ferritin) – anaemia (hypochromic and microcytic) leads to growth and developmental delay with stomatitis and kolionychia

Question 5

Causes of iron deficiency in children

Answer 5

Dietary deficiency –> children are fussy, vegan/vegetarian as children are worse at absorbing non-haem iron, delayed weaning/large milk intake, poverty, coeliac disease, parasite infections (hookworm)

Question 6

Treatment of iron deficiency anaemia in children

Answer 6

Dietary advice –> less milk and more meat, oral or IV iron supplements, if severe can need transfusions
Treat parasite infection and any other causes

Question 7

Acute lymphoblastic leukaemia (ALL)

Answer 7

Commonest Ca in childhood – 500 new cases/yr
Diagnosis - blood count (anaemia, thrombocytopenia, neutropenia) – blood film shows blasts – lymphtyping shows lymphoblasts – marrow aspiration will show >30% blasts

Question 8

Causes of Acute lymphoblastic leukaemia (ALL)

Answer 8

Usually idiopathic but increased risk if exposed to radiation, chemicals, EM fields
Increased risk if downs or Fanconi anaemia

Question 9

Treatment of Acute lymphoblastic leukaemia (ALL)

Answer 9

Myeloablative chemotherapy – Intensive induction of remission –> followed by intensification blocks to kill any remaining cells –> followed by 2-3yrs of low dose OP maintenance treatment
This can be done intrathecally

Question 10

Outcomes of ALL treatment

Answer 10

70-80% of children ‘cured’ - best prognosis if: female, between 1 and 16yrs, if WCC was low at presentation, rapid response, hyperdiploidy

Question 11

Side effects of ALL treatment

Answer 11

Acute –> Naesea and vomiting, pancytopenia (bleeding and infection risk), hair loss
Long term –> Growth/cogntive problems, behavioural/psychological problems, cardiomyopathy, subfertility

Question 12

ALL relapse

Answer 12

If relapse occurs further intensive therapy is started
consider bone marrow donor if remission occurs
Ideally – HLA identical or Haploidentical (sibling or parent)

Question 13

Epidemiology of Sickle cell disease in children

Answer 13

10,000 children with SCD in london - 12,000 in UK
Most common and fastest growing serious genetic disease in Britain
Screened as part of heel prick and can now be screened antenatally

Question 14

Symptoms of SCD in children

Answer 14

Pain from crises - acute and chronic
Stroke risk and protect cognitive function
Pulmonary HTN and acute chest syndrome
Priapism

Question 15

Hydroxycarbamide

Answer 15

Reduces frequency of Sickle cell crises by increasing the production of fetal haemoglobin which prevents sickling

Question 16

Thalassaemia

Answer 16

Quantitative defect in globin chain production – carriers are asymptomatic
Thalassaemia intermedia - some symptoms
Thalassaemia major - if Beta will die without regular transfusions, if alpha die in utero

Question 17

Immune/idiopathic thrombocytopenic purpura (ITP)

Answer 17

Acquired, immune mediated destruction of platelets
Symptoms are purpura and bleeding
Diagnosed by isolated low platelet count
Megkaryocytes in marrow can be normal or increased

Question 18

Treatment of ITP

Answer 18

80% of children will recover in 6months and life-threatening bleeds are rare
Treatment is supportive with immunoglobulins or corticosteroids - if severe may need splenectomy, other immunosuppresants or biologics

Question 19

Wilms Tumour (Nephroblastoma)

Answer 19

Presents <5 (median 3) with abdominal mass (also haematuria, flank pain, anorexia, fever). Unilateral in 95% of cases. 20% will spread to lung. Treat with nephrectomy, chemotherapy and radiotherapy. 80% cure rate

Question 20

Associations of Wilm’s tumour

Answer 20

Beckwith-wiedemann syndrome
WAGR syndrome (Aniridia, GU malformations,mental retardation)
Hemihypertrophy. 1/3 of cases are associated with a mutation of the WT1 gene on chr 11

Question 21

Hand-foot syndrome

Answer 21

Vaso-occulusive crises in pre-school children with Sickle cell. This can be dactylyitis (fingers) or in the feet.

Question 22

Asplenism

Answer 22

Can occur due to surgical removal, sickle cell or rarely coeliac. Can lead to Howell-jolly bodies (basophilic nuclear fragments), pappenheimer bodies and target cells (RBCs with peripherial depigmentation).

Question 23

Acute Myeloid Leukaemia (AML)

Answer 23

Commonest acute leukaemia in adults - risk is increased in downs children (and for ALL).
Mild splenomegaly & fever/fatigue/weight loss/anorexia. Auer Rods are cellular inclusions in bone marrow blast cells which are pathognomic of AML.

Question 24

Polycythaemia

Answer 24

Central Venous Haematocrit of more than 0.65. This hyperviscosity can present with lethargy, hypotonia, hyperbilirubinaemia, hypoglycaemia, seizures, stroke, renal vein thrombosis and NEC

Question 25

Acute intermittent Porphyria (AIP)

Answer 25

A rare autosomal dominant condition resulting in toxic acculation of prophobilinogen and delta aminolaevulinic acid. (5:1/F:M) leading to abdominal pain/vomiting and neuropsychiatric symptoms (motor neuropathy, depression, hypertension & tachycardia) in 20-40yrs. Urine will turn ‘deep red’ on standing.

Question 26

Drug triggers of AIP

Answer 26

Barbiturates, benzo & halothane

Alcohol, COC and sulphonamides.

Question 27

Neonatal jaundice in the presence of haematological conditions

Answer 27

Neonates will already by jaundiced —> any haemaglobinopathy will make this worse.

Question 28

Sickle Cell and UTIs

Answer 28

People with sickle cell are at an increased risk of UTIs

Question 29

Types of sickle cell crisis

Answer 29

Thrombotic (painful) - bones, fingers/feet, spleen, lungs, brain
Sequestration - pooling of blood in spleen or lungs. Causes acute chest syndrome
Aplastic – sudden drop in Hb due to infection by parvovirus
Haemolytic - fall in Hb due to increased haemolysis - rare

Question 30

Signs of beta thalassaemia

Answer 30

“Chipmunk face”
Hepatosplenomegaly
Impaired immunity
Skull X-Ray “hair on end” (extra-medullary haematopoeisis