302. Thalaesaemmia and sickle cell anaemia

Question 1

Discuss the types of sickle cell anaemia?

Answer 1

Sickle cell anaemia- abnormally shaped red cells that leads to vaso-occlusive crisis

Sickle cell trait- no adverse effect, still protective against malaria. may experience signs in hypoxia e.g. anesthesia.

Question 2

How do you differentiate between sickle cell major and sickle cell trait?

Answer 2

Blood film and sickle solubility test- confirms diagnosis but not state

Hb electropheresis- confirms state

Question 3

What other tests can be done to identify sickle cell anemia?

What should be administered once diagnosis identified?

Answer 3

FBC (Hb 60-90) Reticulocyte increase, Bilirubin increase.

pneumococcal vaccine

Question 4

What are the main crisis in sickle cell disease?

Answer 4

vaso-occlusive (painful) crisis- microvascular occlusion often affecting the bone marrow. often triggered by cold, dehydration, infection or hypoxia

Aplastic crisis- paravirus 19 worsens anemia, usually self limiting

Sequestration crisis- atrophic spleen causes organomegaly, anemia and shock. Needs tranfsued

Question 5

Explain what is meant the complication of a painful crisis (vaso-occlusive)

Answer 5

Hands and feet affected <3

Mesenteric ischemia

CNS occlusion- transcranial doppler ultrasound

Avascular necrosis

Question 6

What are the complications of sickle cell anemia

Answer 6

Splenic infarction

Poor growth

Chronic renal failure

Gall stones

Retinal disease

iron overload

Lung damage- pulmonary hypertension

Question 7

How is sickle cell anaemia managed?

Answer 7

hydroxycarbamide (increases fetal heamoglobin)

Hyposplenism, immuno compromise

Big sepsis risk

Question 8

In terms of sickle cell crisis what are important steps to take in initial management

Answer 8

Give prompt generous analgesia. Patient controlled/patient analgesia plan

Crossmatch blood, check FBC, Retic, Sepsis screen.

frequqnelty check for organomegaly and reticulocytes

Rehydrate and keep warm, empirical antibiotics

Give transfusion if Hb falls sharply

Let hematologist know early about admission

Question 9

What is an exchange transfusion?

What are the indications

Answer 9

Reserved or those who are rapidly worseining. Donors blood given in stages and patients blood removed.

Indications- severe chest crisis, suspected CNS event, multiorgan failure

Question 10

What is meant by the acute chest syndrome in sickle cell anaemia?

How is it treated

Answer 10

Pulmonary infiltrates causing pain,fever, tachypnoea and wheeze. Serious!! Typically fat embolus, mycoplasma,chlamydia, virus

Treat as before (empirical ceph and macrolide), Salbutamol, blood transfusion, consider ITU early

Question 11

Explain the heamoglobin chain

What is beta thalasaemmia?

Answer 11

Haemoglobin is made up of two alpha and two beta chains

underproduciton (or no productio) of the beta chain

Question 12

What are the classes of beta thalaseammia?

Answer 12

Beta th. trait- functional anaemia

Beta th. intermedietta- anaemia not rewuiring transfusion and splenomegaly

Beta th. major- presents in first year of life with severe anaemia and failure to thrive.

Question 13

What are the signs of beta thalasaemmia?

Answer 13

Anaemia,
Splenomegaly, 
Failure to thrive
Skull bossing (hair on end)
ostopenia
endocrine dysnfunciton

Question 14

What is the treatment of beta thalaseammia?

Answer 14

Encourage healthy lifestyle, folate supplements

Regular lifelong transfusions to keep Hb>90

iron chelator therapy(desferrioxamine) or absorbic aicd same effect

Splenectomy

treat endocrine dysfunction

marrow transplant may cure.

Question 15

What are the side effects of iron chelator therpay?

Answer 15

Pain, deafness, cataracts, retinal damage.