Sickle Syndromes - study

Question 1

what are sickle syndromes

Answer 1

group of genetic disorders that affect the structure of haemoglobin, resulting in the production of HbS

Question 2

what type of mutation in what codon in what gene causes sickle?

Answer 2

point mutation in codon 6 of the beta globin gene

Question 3

if someone has sickle cell trait, when might they sickle

Answer 3

severe hypoxia e.g. high altitude, under anaesthesia

Question 4

sickle cell trait (HbAS) blood film

Answer 4

normal

Question 5

what is the diagnosis: HbS >80%, no HbA

Answer 5

sickle cell anaemia (HbSS)

Question 6

in sickle disease - what is it called when episodes of tissue infarction occur due to vascular occlusion

Answer 6

sickle crisis

Question 7

what is sickle crisis

Answer 7

episodes of tissue infarction due to vascular occlusion

Question 8

clinical features of sickle cell anaemia

Answer 8

• vaso-occlusive crises
• acute chest syndrome
• pulmonary hypertension
• anaemia

Question 9

investigations

Answer 9

bloods: FBC, Hb, red cell indices, blood film

high performance liquid chromatography (HPLC) or electrophoresis

Question 10

management of a sickle crisis

Answer 10

treatments include:
- high flow oxygen

• IV fluids and opiate analgesia
• red cell exchange transfusion in severe crisis e.g. chest crisis (lung) or brain (stroke)
• antibiotics if evidence of infection

Question 11

which vaccinations are given to sickle cell anaemia patients

Answer 11

• pneumococcus
• meningococcus
• haemophilus

Question 12

how does hydroxycarbamide work in sickle cell anaemia

Answer 12

increases foetal haemoglobin concentrations

Question 13

is hydroxycarbamide teratogenic

Answer 13

yes potentially

Question 14

newer therapies for long term management of sickle cell anaemia

Answer 14

• Crizaniluzumab (p-selectin inhibitor) for treatment of pain crises
• voxelotor (haemoglobin oxygen-affinity modulator) for haemolytic complications