Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate®

Sickle cell trait

Elliott P Vichinsky, MD
Section Editor
Donald H Mahoney, Jr, MD
Deputy Editor
Jennifer S Tirnauer, MD


Sickle cell trait is a benign carrier condition, usually with none of the symptoms of sickle cell anemia or other sickle cell diseases. However, knowledge of sickle cell trait is important in many settings such as preconception counseling and evaluation of rare complications. The screening, diagnosis, potential complications, and routine management of individuals with sickle cell trait are discussed here.

Homozygous sickle cell disease and other sickle cell disease variants (eg, sickle cell beta-thalassemia, hemoglobin SC disease) are discussed in detail separately.

(See "Overview of the clinical manifestations of sickle cell disease".)

(See "Diagnosis of sickle cell disorders".)

(See "Overview of the management and prognosis of sickle cell disease".)


Subscribers log in here

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information or to purchase a personal subscription, click below on the option that best describes you:
Literature review current through: Feb 2017. | This topic last updated: Fri Mar 10 00:00:00 GMT+00:00 2017.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
  1. Motulsky AG. Frequency of sickling disorders in U.S. blacks. N Engl J Med 1973; 288:31.
  2. Michlitsch J, Azimi M, Hoppe C, et al. Newborn screening for hemoglobinopathies in California. Pediatr Blood Cancer 2009; 52:486.
  3. Ojodu J, Hulihan MM, Pope SN, et al. Incidence of sickle cell trait--United States, 2010. MMWR Morb Mortal Wkly Rep 2014; 63:1155.
  4. Nelson DA, Deuster PA, Carter R 3rd, et al. Sickle Cell Trait, Rhabdomyolysis, and Mortality among U.S. Army Soldiers. N Engl J Med 2016; 375:435.
  5. Tsaras G, Owusu-Ansah A, Boateng FO, Amoateng-Adjepong Y. Complications associated with sickle cell trait: a brief narrative review. Am J Med 2009; 122:507.
  6. Gergen PJ, Macri CJ, Murrillo S. The need for sickle cell screening among pediatric latino immigrants. Arch Pediatr Adolesc Med 2002; 156:729.
  7. Lobo CL, Ballas SK, Domingos AC, et al. Newborn screening program for hemoglobinopathies in Rio de Janeiro, Brazil. Pediatr Blood Cancer 2014; 61:34.
  8. Italia Y, Krishnamurti L, Mehta V, et al. Feasibility of a newborn screening and follow-up programme for sickle cell disease among South Gujarat (India) tribal populations. J Med Screen 2015; 22:1.
  9. Shrikhande AV, Arjunan A, Agarwal A, et al. Prevalence of the β(S) gene among scheduled castes, scheduled tribes and other backward class groups in Central India. Hemoglobin 2014; 38:230.
  10. Guler E, Garipardic M, Dalkiran T, Davutoglu M. Premarital screening test results for β-thalassemia and sickle cell anemia trait in east Mediterranean region of Turkey. Pediatr Hematol Oncol 2010; 27:608.
  11. Al Hosani H, Salah M, Osman HM, et al. Incidence of haemoglobinopathies detected through neonatal screening in the United Arab Emirates. East Mediterr Health J 2005; 11:300.
  12. Al-Riyami A, Ebrahim GJ. Genetic Blood Disorders Survey in the Sultanate of Oman. J Trop Pediatr 2003; 49 Suppl 1:i1.
  13. Loukopoulos D. Haemoglobinopathies in Greece: prevention programme over the past 35 years. Indian J Med Res 2011; 134:572.
  14. Ladis V, Karagiorga-Lagana M, Tsatra I, Chouliaras G. Thirty-year experience in preventing haemoglobinopathies in Greece: achievements and potentials for optimisation. Eur J Haematol 2013; 90:313.
  15. Hanchard NA, Hambleton I, Harding RM, McKenzie CA. Predicted declines in sickle allele frequency in Jamaica using empirical data. Am J Hematol 2006; 81:817.
  16. Saint-Martin C, Romana M, Bibrac A, et al. Universal newborn screening for haemoglobinopathies in Guadeloupe (French West Indies): a 27-year experience. J Med Screen 2013; 20:177.
  17. Taylor C, Kavanagh P, Zuckerman B. Sickle cell trait--neglected opportunities in the era of genomic medicine. JAMA 2014; 311:1495.
  18. Lang CW, Ross LF. Maternal attitudes about sickle cell trait identification in themselves and their infants. J Natl Med Assoc 2010; 102:1065.
  19. Treadwell MJ, McClough L, Vichinsky E. Using qualitative and quantitative strategies to evaluate knowledge and perceptions about sickle cell disease and sickle cell trait. J Natl Med Assoc 2006; 98:704.
  20. Kavanagh PL, Wang CJ, Therrell BL, et al. Communication of positive newborn screening results for sickle cell disease and sickle cell trait: variation across states. Am J Med Genet C Semin Med Genet 2008; 148C:15.
  21. Hinton CF, Neuspiel DR, Gubernick RS, et al. Improving newborn screening follow-up in pediatric practices: quality improvement innovation network. Pediatrics 2012; 130:e669.
  22. CDC. Key findings: Improving newborn screening follow-up in pediatric practices: Quality Improvement Innovation Network. www.cdc.gov (Accessed on March 31, 2014).
  23. Ross LF. A re-examination of the use of ethnicity in prenatal carrier testing. Am J Med Genet A 2012; 158A:19.
  24. Azonobi IC, Anderson BL, Byams VR, et al. Obstetrician-gynecologists' knowledge of sickle cell disease screening and management. BMC Pregnancy Childbirth 2014; 14:356.
  25. Blinder MA, Russel S. Exertional sickling: questions and controversy. Hematol Rep 2014; 6:5502.
  26. Anzalone ML, Green VS, Buja M, et al. Sickle cell trait and fatal rhabdomyolysis in football training: a case study. Med Sci Sports Exerc 2010; 42:3.
  27. Eichner ER. Sickle cell trait. J Sport Rehabil 2007; 16:197.
  28. http://www.ncaa.org/wps/wcm/connect/public/NCAA/Health+and+Safety/Sickle+Cell/Sickle+Cell+Landing+Page (Accessed on November 21, 2012).
  29. O'Connor FG, Bergeron MF, Cantrell J, et al. ACSM and CHAMP summit on sickle cell trait: mitigating risks for warfighters and athletes. Med Sci Sports Exerc 2012; 44:2045.
  30. Bain BJ. Laboratory techniques for the identification of abnormalities of globin chain synthesis. In: Haemoglobinopathy Diagnosis, 2nd ed, Blackwell, Malden 2006. p.43.
  31. La Pean A, Farrell MH. Initially misleading communication of carrier results after newborn genetic screening. Pediatrics 2005; 116:1499.
  32. Farrell MH, Kuruvilla P. Assessment of parental understanding by pediatric residents during counseling after newborn genetic screening. Arch Pediatr Adolesc Med 2008; 162:199.
  33. Rosas-Blum E, Shirsat P, Leiner M. Communicating genetic information: a difficult challenge for future pediatricians. BMC Med Educ 2007; 7:17.
  34. Koopmans J, Ross LF. Identification and management of sickle cell trait by young physicians. J Natl Med Assoc 2012; 104:299.
  35. Kladny B, Williams A, Gupta A, et al. Genetic counseling following the detection of hemoglobinopathy trait on the newborn screen is well received, improves knowledge, and relieves anxiety. Genet Med 2011; 13:658.
  36. Moseley KL, Nasr SZ, Schuette JL, Campbell AD. Who counsels parents of newborns who are carriers of sickle cell anemia or cystic fibrosis? J Genet Couns 2013; 22:218.
  37. Ashcroft MT, Desai P. Mortality and morbidity in Jamaican adults with sickle-cell trait and with normal haemoglobin followed up for twelve years. Lancet 1976; 2:784.
  38. Castro O, Rana SR, Bang KM, Scott RB. Age and prevalence of sickle-cell trait in a large ambulatory population. Genet Epidemiol 1987; 4:307.
  39. Ashcroft MT, Miall WE, Milner PF. A comparison between the characteristics of Jamaican adults with normal hemoglobin and those with sickle cell trait. Am J Epidemiol 1969; 90:236.
  40. Tuck SM, Studd JW, White JM. Pregnancy in sickle cell disease in the UK. Br J Obstet Gynaecol 1983; 90:112.
  41. Bucknor MD, Goo JS, Coppolino ML. The risk of potential thromboembolic, renal and cardiac complications of sickle cell trait. Hemoglobin 2014; 38:28.
  42. Hicks PJ, Langefeld CD, Lu L, et al. Sickle cell trait is not independently associated with susceptibility to end-stage renal disease in African Americans. Kidney Int 2011; 80:1339.
  43. Key NS, Connes P, Derebail VK. Negative health implications of sickle cell trait in high income countries: from the football field to the laboratory. Br J Haematol 2015; 170:5.
  44. Derebail VK, Lacson EK Jr, Kshirsagar AV, et al. Sickle trait in African-American hemodialysis patients and higher erythropoiesis-stimulating agent dose. J Am Soc Nephrol 2014; 25:819.
  45. Lane PA, Githens JH. Splenic syndrome at mountain altitudes in sickle cell trait. Its occurrence in nonblack persons. JAMA 1985; 253:2251.
  46. Franklin QJ, Compeggie M. Splenic syndrome in sickle cell trait: four case presentations and a review of the literature. Mil Med 1999; 164:230.
  47. Castro O, Finch SC. Letter: Splenic infarction in sickle-cell trait: are whites more susceptible? N Engl J Med 1974; 291:630.
  48. Goodman J, Hassell K, Irwin D, et al. The splenic syndrome in individuals with sickle cell trait. High Alt Med Biol 2014; 15:468.
  49. Matta A, Tandra PK, Berim L. Priapism in a patient with sickle cell trait using marijuana. BMJ Case Rep 2014; 2014.
  50. Bacsu CD, Metcalfe PD. Priapism in an infant with sickle cell trait after cardiac transplant. Urology 2012; 80:928.
  51. Birnbaum BF, Pinzone JJ. Sickle cell trait and priapism: a case report and review of the literature. Cases J 2008; 1:429.
  52. Gharaibeh A, Savage HI, Scherer RW, et al. Medical interventions for traumatic hyphema. Cochrane Database Syst Rev 2013; :CD005431.
  53. Kaplowitz K, Nobe M, Abazari A, Honkanen R. Trabeculectomy for traumatic hyphema in sickle cell trait. Semin Ophthalmol 2015; 30:297.
  54. Austin H, Key NS, Benson JM, et al. Sickle cell trait and the risk of venous thromboembolism among blacks. Blood 2007; 110:908.
  55. Folsom AR, Tang W, Roetker NS, et al. Prospective study of sickle cell trait and venous thromboembolism incidence. J Thromb Haemost 2015; 13:2.
  56. Pintova S, Cohen HW, Billett HH. Sickle cell trait: is there an increased VTE risk in pregnancy and the postpartum? PLoS One 2013; 8:e64141.
  57. Roger VL, Go AS, Lloyd-Jones DM, et al. Heart disease and stroke statistics--2012 update: a report from the American Heart Association. Circulation 2012; 125:e2.
  58. Steen RG, Hankins GM, Xiong X, et al. Prospective brain imaging evaluation of children with sickle cell trait: initial observations. Radiology 2003; 228:208.
  59. Caughey MC, Loehr LR, Key NS, et al. Sickle cell trait and incident ischemic stroke in the Atherosclerosis Risk in Communities study. Stroke 2014; 45:2863.
  60. Heller P. Risk in sickle-cell trait. Ann Intern Med 1973; 78:613.
  61. Bile A, Le Gallais D, Mercier B, et al. Blood lactate concentrations during incremental exercise in subjects with sickle cell trait. Med Sci Sports Exerc 1998; 30:649.
  62. Pearl W, Zeballos RJ, Gregory G, Weisman IM. ECG in sickle cell trait at rest and during exercise and hypoxia. J Electrocardiol 1994; 27:215.
  63. Sara F, Hardy-Dessources MD, Voltaire B, et al. Lactic response in sickle cell trait carriers in comparison with subjects with normal hemoglobin. Clin J Sport Med 2003; 13:96.
  64. Weisman IM, Zeballos RJ, Johnson BD. Cardiopulmonary and gas exchange responses to acute strenuous exercise at 1,270 meters in sickle cell trait. Am J Med 1988; 84:377.
  65. Weisman IM, Zeballos RJ, Johnson BD. Effect of moderate inspiratory hypoxia on exercise performance in sickle cell trait. Am J Med 1988; 84:1033.
  66. Weisman IM, Zeballos RJ, Martin TW, Johnson BD. Effect of Army basic training in sickle-cell trait. Arch Intern Med 1988; 148:1140.
  67. Stark AD, Janerich DT, Jereb SK. The incidence and causes of death in a follow-up study of individuals with haemoglobin AS and AA. Int J Epidemiol 1980; 9:325.
  68. Kark JA, Posey DM, Schumacher HR, Ruehle CJ. Sickle-cell trait as a risk factor for sudden death in physical training. N Engl J Med 1987; 317:781.
  69. Sherry P. Sickle cell trait and rhabdomyolysis: case report and review of the literature. Mil Med 1990; 155:59.
  70. Rosenthal MA, Parker DJ. Collapse of a young athlete. Ann Emerg Med 1992; 21:1493.
  71. Sanchez CE, Jordan KM. Exertional sickness. Am J Med 2010; 123:27.
  72. Harmon KG, Drezner JA, Klossner D, Asif IM. Sickle cell trait associated with a RR of death of 37 times in National Collegiate Athletic Association football athletes: a database with 2 million athlete-years as the denominator. Br J Sports Med 2012; 46:325.
  73. Mitchell BL. Sickle cell trait and sudden death--bringing it home. J Natl Med Assoc 2007; 99:300.
  74. Scheinin L, Wetli CV. Sudden death and sickle cell trait: medicolegal considerations and implications. Am J Forensic Med Pathol 2009; 30:204.
  75. Van Camp SP, Bloor CM, Mueller FO, et al. Nontraumatic sports death in high school and college athletes. Med Sci Sports Exerc 1995; 27:641.
  76. Monplaisir N, Merault G, Poyart C, et al. Hemoglobin S Antilles: a variant with lower solubility than hemoglobin S and producing sickle cell disease in heterozygotes. Proc Natl Acad Sci U S A 1986; 83:9363.
  77. Witkowska HE, Lubin BH, Beuzard Y, et al. Sickle cell disease in a patient with sickle cell trait and compound heterozygosity for hemoglobin S and hemoglobin Quebec-Chori. N Engl J Med 1991; 325:1150.
  78. Bain BJ. Sickle cell haemoglobin and its interactions with other variant haemoglobins and with the thalassaemias. In: Haemoglobinopathy Diagnosis, 2nd ed, Blackwell, Malden, MA 2006. p.181.
  79. Swensen JJ, Agarwal AM, Esquilin JM, et al. Sickle cell disease resulting from uniparental disomy in a child who inherited sickle cell trait. Blood 2010; 116:2822.
  80. Cohen-Solal M, Préhu C, Wajcman H, et al. A new sickle cell disease phenotype associating Hb S trait, severe pyruvate kinase deficiency (PK Conakry), and an alpha2 globin gene variant (Hb Conakry). Br J Haematol 1998; 103:950.
  81. Friedman GD, Cutter GR, Donahue RP, et al. CARDIA: study design, recruitment, and some characteristics of the examined subjects. J Clin Epidemiol 1988; 41:1105.
  82. Liem RI, Chan C, Vu TT, et al. Association among sickle cell trait, fitness, and cardiovascular risk factors in CARDIA. Blood 2017; 129:723.
  83. Bello NA, Hyacinth HI, Roetker NS, et al. Sickle cell trait is not associated with an increased risk of heart failure or abnormalities of cardiac structure and function. Blood 2017; 129:799.
  84. Austin H, Lally C, Benson JM, et al. Hormonal contraception, sickle cell trait, and risk for venous thromboembolism among African American women. Am J Obstet Gynecol 2009; 200:620.e1.
  85. Haddad LB, Curtis KM, Legardy-Williams JK, et al. Contraception for individuals with sickle cell disease: a systematic review of the literature. Contraception 2012; 85:527.
  86. Section on Hematology/Oncology Committee on Genetics, American Academy of Pediatrics. Health supervision for children with sickle cell disease. Pediatrics 2002; 109:526.
  87. Tita AT, Biggio JR, Chapman V, et al. Perinatal and maternal outcomes in women with sickle or hemoglobin C trait. Obstet Gynecol 2007; 110:1113.
  88. Tan TL, Seed P, Oteng-Ntim E. Birthweights in sickle cell trait pregnancies. BJOG 2008; 115:1116.
  89. Amar KO, Bourdonné O, Bruneau S, et al. Assessment of leucoreduction of sickle cell trait blood: quality of the filtered product. Blood Transfus 2014; 12 Suppl 1:s193.
  90. Fitzhugh CD, Hsieh MM, Bolan CD, et al. Granulocyte colony-stimulating factor (G-CSF) administration in individuals with sickle cell disease: time for a moratorium? Cytotherapy 2009; 11:464.
  91. ASH Statement on Screening for Sickle Cell Trait and Athletic Participation: http://www.hematology.org/Advocacy/Policy-Statements/7704.aspx (Accessed on January 26, 2012).
  92. http://www.hematology.org/Thehematologist/President/1070.aspx (Accessed on November 21, 2014).
  93. Casa DJ, Armstrong LE, Hillman SK, et al. National athletic trainers' association position statement: fluid replacement for athletes. J Athl Train 2000; 35:212.
  94. American College of Sports Medicine, Sawka MN, Burke LM, et al. American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc 2007; 39:377.