However, it is unclear if rigorous monitoring is necessary in SCD patients. Recent studies have not demonstrated significant bone marrow suppression [46]. Therefore, it is reasonable that HU could be prescribed and monitored by primary care physicians with the use of pre-set practice guidelines and consultation with a haematologist. Chronic blood transfusions have been demonstrated to reduce the risk of both primary and secondary stroke and prevent repeated ACS [28], [33] and [50]. Blood transfusions can be given as simple or exchange transfusions

in which patients’ RBCs are removed by pheresis or by manual exchange and replaced with healthy RBCs. The aim of exchange transfusion therapy is to reduce HbS to below 30%, which effectively AZD2281 cell line prevents stroke and SIs [29]. SGI-1776 ic50 However, chronic transfusions and exchange transfusions may lead to iron overload and iron deposition in organs (liver, heart, pituitary, and pancreas), with end-organ damage potentially occurring before the onset of symptoms. Thus, although blood transfusions may shorten VOE, it is important to reserve transfusion therapy only for life-threatening complications such as ACS, splenic sequestration,

aplastic crisis, and cerebral infarction. Patients with SCD should be treated with permissive anaemia (even when the haemoglobin level is below an individual’s baseline) to prevent the detrimental effects of iron toxicity. All patients requiring long-term transfusion therapy or those who have received multiple lifetime transfusions should be started on iron chelation therapy early and monitored closely for the deleterious Dehydratase effects of iron overload [51]. Iron chelators, which form a complex with iron to promote its excretion, include deferoxamine, deferiprone, and deferasirox, with oral deferasirox currently being the most frequently used [52]. The gold standard for assessing iron overload has shifted in the last decade from liver biopsies, which are sample-dependent

and invasive, to specialized T2* MRI assessments of liver iron concentration [51]. Other options for monitoring transfusional iron overload include serial laboratory evaluations (ferritin levels), which are much less accurate. TCD ultrasonography screening should be performed annually in patients aged 2–26 years to predict stroke risk and initiate preventative therapies. TCDs measure abnormal blood flow velocity in large intracranial arteries. The STOP study conclusively demonstrated that patients with flow velocity ≥ 200 cm/s time-averaged mean of the maximum (TAMM) had a 10% increased risk of stroke, which can be reduced by simple or exchange transfusions [29]. Studies have also demonstrated that in patients who have suffered a stroke, subsequent stroke can be prevented with monthly transfusion therapy [42], [53] and [54].