National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Sickle cell anemia



Sickle cell anemia is a disease in which the body produces abnormally shaped red blood cells that have a crescent or sickle shape. These cells do not last as long as normal, round, red blood cells, which leads to anemia (low number of red blood cells). The sickle cells also get stuck in blood vessels, blocking blood flow.[1] Signs and symptoms of sickle cell disease usually begin in early childhood and may include anemia, repeated infections, and periodic episodes of pain (called crises). This condition is caused by mutations in the HBB gene and is inherited in an autosomal recessive pattern.[2] Treatment typically focuses on controlling symptoms and may include pain medicines during crises; hydroxyurea to reduce the number of pain episodes; antibiotics and vaccines to prevent bacterial infections; and blood transfusions.[1] On July 7, 2017, the FDA in the United States approved the use of Endari (prescription grade L-glutamine) to reduce the number of sickle cell crisis. Endari is the first FDA approved treatment that is also available for children with sickle cell disease five years of age and older.[3]
Last updated: 7/14/2017

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 37 |
Medical Terms Other Names
Learn More:
HPO ID
100% of people have these symptoms
Chronic hemolytic anemia 0004870
80%-99% of people have these symptoms
Recurrent infections
Frequent infections
Frequent, severe infections
Increased frequency of infection
infections, recurrent
Predisposition to infections
Susceptibility to infection
[ more ]
0002719
30%-79% of people have these symptoms
Abnormality of the spleen 0001743
Avascular necrosis
Death of bone due to decreased blood supply
0010885
Chest pain 0100749
Iron deficiency anemia 0001891
Leukocytosis
Elevated white blood count
High white blood count
Increased blood leukocyte number
[ more ]
0001974
Osteomyelitis
Bone infection
0002754
Osteoporosis 0000939
Pigment gallstones 0011981
Reticulocytosis
Increased immature red blood cells
Increased number of immature red blood cells
[ more ]
0001923
Thrombocytosis
Increased number of platelets in blood
0001894
5%-29% of people have these symptoms
Abnormality of the nervous system
Neurologic abnormalities
Neurological abnormality
[ more ]
0000707
Cholestasis
Slowed or blocked flow of bile from liver
0001396
Elevated serum creatinine
Elevated creatinine
High blood creatinine level
Increased creatinine
Increased serum creatinine
[ more ]
0003259
Hypoxemia
Low blood oxygen level
0012418
Increased lactate dehydrogenase level 0025435
Persistence of hemoglobin F 0011904
Unconjugated hyperbilirubinemia 0008282
1%-4% of people have these symptoms
Increased mean corpuscular volume 0005518
Microcytic anemia 0001935
Percent of people who have these symptoms is not available through HPO
Abdominal pain
Pain in stomach
Stomach pain
[ more ]
0002027
Autosomal recessive inheritance 0000007
Cardiomegaly
Enlarged heart
Increased heart size
[ more ]
0001640
Cholelithiasis
Gallstones
0001081
Hematuria
Blood in urine
0000790
Hemolytic anemia 0001878
Hepatomegaly
Enlarged liver
0002240
Hypertension 0000822
Increased red cell sickling tendency 0008346
Jaundice
Yellow skin
Yellowing of the skin
[ more ]
0000952
Priapism 0200023
Recurrent bacterial infections
Bacterial infections, recurrent
Frequent bacterial infections
Increased susceptibility to bacterial infections
Recurrent major bacterial infections
[ more ]
0002718
Renal insufficiency
Renal failure
Renal failure in adulthood
[ more ]
0000083
Retinopathy
Noninflammatory retina disease
0000488
Splenomegaly
Increased spleen size
0001744
Stroke 0001297
Showing of 37 |
Last updated: 7/1/2020

Sickle cell anemia is inherited in an autosomal recessive pattern, which means that both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.[2] In regards to sickle cell anemia, a person who carries one copy of the mutated gene is said to be a carrier for the condition, or to have sickle cell trait. When two people who are carriers of an autosomal recessive condition have a child, there is a 25% (1 in 4) chance that the child will have the condition, a 50% (1 in 2) chance that the child will be a carrier like each of the parents, and a 25% (1 in 4) chance that the child will not have the condition and not be a carrier.
Last updated: 12/14/2015

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Newborn Screening

  • An ACTion (ACT) sheet is available for this condition that describes the short-term actions a health professional should follow when an infant has a positive newborn screening result. ACT sheets were developed by experts in collaboration with the American College of Medical Genetics.
  • An Algorithm flowchart is available for this condition for determining the final diagnosis in an infant with a positive newborn screening result. Algorithms are developed by experts in collaboration with the American College of Medical Genetics.
  • Baby's First Test is the nation's newborn screening education center for families and providers. This site provides information and resources about screening at the local, state, and national levels and serves as the Clearinghouse for newborn screening information.
  • National Newborn Screening and Global Resource Center (NNSGRC) provides information and resources in the area of newborn screening and genetics to benefit health professionals, the public health community, consumers and government officials.
  • The Newborn Screening Coding and Terminology Guide has information on the standard codes used for newborn screening tests. Using these standards helps compare data across different laboratories. This resource was created by the National Library of Medicine.

The resources below provide information about treatment options for this condition. If you have questions about which treatment is right for you, talk to your healthcare professional.

Management Guidelines

  • Project OrphanAnesthesia is a project whose aim is to create peer-reviewed, readily accessible guidelines for patients with rare diseases and for the anesthesiologists caring for them. The project is a collaborative effort of the German Society of Anesthesiology and Intensive Care, Orphanet, the European Society of Pediatric Anesthesia, anesthetists and rare disease experts with the aim to contribute to patient safety.

FDA-Approved Treatments

The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.


If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources


Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
Differential diagnoses include other hereditary hemolytic diseases.
Visit the Orphanet disease page for more information.

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Sickle cell anemia. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.
  • The Sickle Transplant Alliance for Research (STAR) is a non-profit organization created by a group of pediatric hematology and stem cell transplant doctors to conduct research to create better transplant approaches for individuals with sickle cell disease. STAR provides critical funding and an organized collaborative network where clinical trials can be conducted at many different institutions.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease


Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Education Resources

  • The Genetics Education Materials for School Success (GEMSS) aims to assure that all children with genetic health conditions succeed in school-life. Their Web site offers general and condition-specific education resources to help teachers and parents better understand the needs of students who have genetic conditions.

Community Resources

  • The Job Accommodation Network (JAN) has information on workplace accommodations and disability employment issues related to this condition. JAN is a service of the Office of Disability Employment Policy in the U.S. Department of Labor.

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • Genetics Home Reference (GHR) contains information on Sickle cell anemia. This website is maintained by the National Library of Medicine.
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The National Heart, Lung, and Blood Institute (NHLBI) has information on this topic. NHLBI is part of the National Institutes of Health and supports research, training, and education for the prevention and treatment of heart, lung, and blood diseases.
  • The National Human Genome Research Institute's (NHGRI) website has an information page on this topic. NHGRI is part of the National Institutes of Health and supports research on the structure and function of the human genome and its role in health and disease.
  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.
  • The Screening, Technology And Research in Genetics (STAR-G) Project has a fact sheet on this condition, which was written specifically for families that have received a diagnosis as a result of newborn screening. This fact sheet provides general information about the condition and answers questions that are of particular concern to parents.

In-Depth Information

  • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Sickle cell anemia. Click on the link to view a sample search on this topic.

Selected Full-Text Journal Articles


Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.


  1. Gersten T. Sickle cell anemia. MedlinePlus. February 1, 2016; https://medlineplus.gov/ency/article/000527.htm.
  2. Sickle cell disease. Genetics Home Reference. August 2012; http://ghr.nlm.nih.gov/condition/sickle-cell-disease.
  3. FDA approved L-glutamine powder for the treatment of sickle cell disease. U.S. Food and Drug Administration: Approved Drugs. July 7, 2017; https://www.fda.gov/Drugs/InformationOnDrugs/ApprovedDrugs/ucm566097.htm.