What is the lifespan of a sickled red blood cell (RBC)?

From the Guidelines

The lifespan of a sickled red blood cell is approximately 10-20 days, which is significantly shorter than the normal red blood cell lifespan of about 120 days. This shortened survival occurs because sickled cells are more rigid and fragile than normal red blood cells. When hemoglobin S (the abnormal hemoglobin in sickle cell disease) deoxygenates, it forms polymers that distort the red blood cell into the characteristic sickle shape, as described in the guideline on the peri-operative management of patients with sickle cell disease 1. These misshapen cells cannot easily navigate through small blood vessels and are more likely to be destroyed in the spleen. The body continuously tries to replace these damaged cells, but often cannot keep pace with their destruction, leading to chronic anemia in people with sickle cell disease.

The pathophysiology of sickle cell disease is complex and involves a continuous cycle of sickling and un-sickling as red cells travel to the peripheries and return to the lungs, as explained in the guideline 1. If the red cells are delayed in their return to the lungs, the polymerisation becomes more extensive, leading to the formation of irreversibly sickled cells and red cell haemolysis. Damaged red cells are removed by the reticulo-endothelial system, and changes in the red cell membrane cause increased adherence to the vascular endothelium, which leads to vaso-occlusion, ischaemia-reperfusion injury, and end-organ damage.

The management of patients with sickle cell disease has improved markedly in recent decades, with a focus on prevention and management of complications from birth, and death in childhood is uncommon in the UK, as reported in the guideline on the peri-operative management of patients with sickle cell disease 1. Survival up to the 7th decade can be expected with optimal multidisciplinary care in a specialist haematology clinic. However, patients with sickle cell disease may still present with various complications, including acute chest crisis, acute painful crisis, or stroke, which can be mitigated with careful planning, assessment of comorbidities, and multidisciplinary team working.

Key points to consider in the management of sickle cell disease include:

• The importance of early diagnosis and treatment to prevent complications
• The need for multidisciplinary care, including haematology, surgery, and other specialties as needed
• The risk of peri-operative complications, including sickle-related and non-sickle-related complications
• The importance of careful planning and assessment of comorbidities to mitigate these risks.

From the Research

Life Span of a Sickled Cell

• The life span of a sickled cell is not directly stated in the provided studies, however, it is known that sickled cells have a shorter life span than normal red blood cells due to hemolysis 2.
• Sickle cell disease is characterized by hemolytic anemia, which results in the destruction of red blood cells 2, 3.
• The average life expectancy of individuals with sickle cell disease is 20 years less than the general population 2.
• Treatment options such as hydroxyurea, L-glutamine, crizanlizumab, and voxelotor have been shown to reduce the frequency of painful crises and improve quality of life, but their effect on the life span of individual sickled cells is not specified 2, 3, 4.
• Hematopoietic stem cell transplant is the only curative therapy for sickle cell disease, but it is limited by donor availability and is typically reserved for severe cases 2, 5.

Factors Affecting Life Span

• The life span of sickled cells can be influenced by various factors, including the frequency of painful crises, the presence of other complications such as stroke or nephropathy, and the effectiveness of treatment 2, 3.
• Hydroxyurea has been shown to increase fetal hemoglobin and reduce red blood cell sickling, which may help to improve the life span of sickled cells 2, 3, 6.
• Regular blood transfusions can also help to reduce the burden of sickled cells and improve overall health outcomes, but may be associated with excessive iron stores and other complications 5.