What you need to know about sickle cell disease

Sickle cell disease is an inherited blood disorder in which red blood cells are formed in an abnormal, stiff crescent shape, rather than a round, flexible disc shape. Dr. Titilope Fasipe, assistant professor of pediatrics – hematology at Baylor College of Medicine and co-director of the Sickle Cell Program at Texas Children’s Hospital, shares what patients and families need to know about this disease.

Complications of sickle cell disease

“Because blood flows all over the body, sickle cell disease can impact any part of the body,” Fasipe said. “The abnormal crescent shape causes red blood cells to get stuck in small blood vessels, which can lead to severe complications.”

The most severe complications of sickle cell disease include stroke, avascular necrosis (in which bone tissue dies due to lack of blood flow), issues with the spleen and immune system, eye and kidney disease and pain.

“When red blood cells get stuck and oxygen is not reaching a part of the body, that part starts screaming out for help, causing pain,” Fasipe said. “Some people with sickle cell disease experience pain occasionally, and some struggle with pain every day.”

Screening and treatment

Sickle cell disease impacts about 8 million people worldwide and about 100,000 people in the U.S., according to the National Heart, Lung and Blood Institute, making it what Fasipe calls a common rare disorder. It is most prevalent in sub-Saharan Africa and India, but it can be found all around the world. Today, most people with sickle cell disease have African ancestry.

All babies born in the U.S. are tested for sickle cell disease as part of newborn screening. This early diagnosis allows families to meet with a hematologist and discuss treatment options from an early age.

“In babies and young children, the thing we are most worried about is infection,” Fasipe said. “Most babies with sickle cell will be treated with penicillin until about age 5. They will also receive a few extra vaccines.”

The primary medication used to treat sickle cell disease is called hydroxyurea, which prevents cells from becoming abnormally shaped, thereby limiting blockage in blood vessels. This medication can be given as early as nine months of age. In the last decade, the Food and Drug Administration has approved additional medications that treat sickle cell disease. These drugs target underlying issues in the disease through other methods, such as reducing toxic oxygen levels and modifying red blood cells to be less sticky.

Researchers continue to study new therapies for sickle cell disease. Clinical trials are underway, including two study sites at

Texas Children’s Hospital, to investigate drugs that increase hemoglobin and address anemia, or low blood count, caused by sickle cell disease. Learn more about those trials here and here.

Curing sickle cell disease

In addition to medications to manage sickle cell disease, two treatments now exist to target curing the disease. For several decades, a bone marrow transplant was the only curative option for patients. But Fasipe says that for many, this treatment may not be feasible. Some patients do not have a donor match within their family, and because many sickle cell patients come from ethnic minority backgrounds, finding a donor within the National Marrow Donor Program can be challenging.

Gene therapy, approved for sickle cell disease in December 2023, allows the patient to be their own donor. The patient’s cells are genetically modified in a lab and then given back to the patient as a bone marrow transplant. Right now, gene therapies can only be delivered via transplant. But Fasipe envisions a future with delivery methods that are even easier for the patient.

“What if I could go to my doctor’s office and get an injection and the gene therapy goes into my body and fixes the cells inside of me without me having to do the transplant? One day, it will be something we test in humans,” Fasipe said. “We’re glad for those that have been able to close the chapter of sickle cell disease in their lives, and we’re hopeful that more people will have that story as well.”

By Molly Chiu

Find more resources about gene therapy and transplantation for sickle cell disease from the National Heart, Lung and Blood Institute and the American Society of Hematology.