Complications associated with sickle cell trait: a brief narrative review

Am J Med. 2009 Jun;122(6):507-12. doi: 10.1016/j.amjmed.2008.12.020. Epub 2009 Apr 24.


Sickle cell trait occurs in approximately 300 million people worldwide, with the highest prevalence of approximately 30% to 40% in sub-Saharan Africa. Long considered a benign carrier state with relative protection against severe malaria, sickle cell trait occasionally can be associated with significant morbidity and mortality. Sickle cell trait is exclusively associated with rare but often fatal renal medullary cancer. Current cumulative evidence is convincing for associations with hematuria, renal papillary necrosis, hyposthenuria, splenic infarction, exertional rhabdomyolysis, and exercise-related sudden death. Sickle cell trait is probably associated with complicated hyphema, venous thromboembolic events, fetal loss, neonatal deaths, and preeclampsia, and possibly associated with acute chest syndrome, asymptomatic bacteriuria, and anemia in pregnancy. There is insufficient evidence to suggest an independent association with retinopathy, cholelithiasis, priapism, leg ulcers, liver necrosis, avascular necrosis of the femoral head, and stroke. Despite these associations, the average life span of individuals with sickle cell trait is similar to that of the general population. Nonetheless, given the large number of people with sickle cell trait, it is important that physicians be aware of these associations.

Publication types

  • Review

MeSH terms

  • Africa South of the Sahara / epidemiology
  • Carcinoma, Medullary / etiology
  • Chest Pain / etiology
  • Death, Sudden / etiology
  • Fatigue / etiology
  • Female
  • Hematuria / etiology
  • Humans
  • Hyphema / etiology
  • Kidney Neoplasms / etiology
  • Kidney Papillary Necrosis / etiology
  • Pre-Eclampsia / etiology
  • Pregnancy
  • Pregnancy Complications, Hematologic / etiology
  • Prevalence
  • Rhabdomyolysis / etiology
  • Risk Factors
  • Sickle Cell Trait / complications*
  • Sickle Cell Trait / epidemiology*
  • Sickle Cell Trait / mortality
  • Splenic Infarction / etiology
  • Venous Thromboembolism / etiology