General Condition Information
- Hb S/C
- Hb S/C disease
- Hemoglobin S/C Disease
- Hemoglobin SC disease
- Hemoglobin sickle C disease
- S, C disease
- S. C Disease
- S/C disease
- SC disease
- Sickle C disease
- Sickle cell anemia
- Sickle cell disease
- Sickle cell disease (Hemoglobin SC)
- Sickle cell disease (hemoglobinopathies)
- Sickle cell hemoglobin C disease
- Sickle hemoglobin C disease
- Sickle-C disease
- Sickle-hemoglobin C disease
- Sickle/hemoglobin C disease
- Each year, over a thousand babies are born in the U.S. with sickle cell conditions like S,C disease.
- Sickle cell conditions are more common in African American babies, and S,C disease is also more common in babies from South and Central America and the Caribbean islands.
- Visit GeneReviews to learn more about how often sickle cell conditions occur.
What is S,C disease
S,C disease is an inherited (genetic) condition that affects the hemoglobin in blood. Hemoglobin is a part of your red blood cells, which carry oxygen in your body. In S,C disease, normal hemoglobin is replaced with mostly hemoglobin S (also called sickle hemoglobin) and hemoglobin C.
S,C disease is a form of sickle cell disease. Normal blood cells are round and shaped like doughnuts. Babies with S,C disease have red blood cells that sickle (or become crescent moon-shaped) instead of staying round or doughnut-shaped. The sickle shape of red blood cells in babies with S,C disease means the red blood cells have a harder time bringing oxygen to the body. Sickle cells also break down more quickly and can get stuck in the blood vessels. This causes the signs and symptoms of the condition.
Newborn Screening and Follow-Up
Newborn screening for S,C disease is done using a small amount of blood collected from your baby’s heel. To learn more about this process, visit the Blood Spot Screening page.
During screening, a special machine measures certain types of hemoglobins in your baby’s blood. Babies with different types of hemoglobins might have S,C disease.
If your baby’s blood spot screening result for S,C disease is out-of-range, your baby’s health care provider will contact you. Together, you will discuss next steps and follow-up plans.
An out-of-range screening result usually means that your baby has the condition and that your baby needs more follow-up testing. To learn more about screening results, visit the Blood Spot Screening Results page.
Your baby may need the following tests after an out-of-range screening result:
- Blood tests
- Genetic testing using a blood sample
You should complete any recommended follow-up testing as soon as possible. Babies with this condition can have serious health problems soon after birth if they are not diagnosed and treated quickly.
False-positive newborn screening results for this condition are rare. However, screening samples that are collected after a baby receives red blood cells from someone else (a red cell transfusion) will be inaccurate.
Newborn screening helps babies lead healthier lives. If your baby has an out-of-range result, follow up with your health care provider quickly. It is important to follow their instructions. Your baby may need to get treatment right away, even if they are not showing signs or symptoms. In some cases, your baby’s health care provider may decide it is best to watch (monitor) your baby to decide next steps. Careful monitoring and early treatment will help your baby stay as healthy as possible.
Many infants with S,C disease do not have signs and symptoms of the condition until later in life. In some cases, signs of S,C disease can appear within two months after birth.
Many children may not have any symptoms until they are already very sick. It is important to see a doctor and start treatment quickly.
Signs of the condition may include the following:
- Serious infections
- Large spleen (usually found during a health care provider visit)
- Pain or painful swelling in hands or feet
- Difficulty breathing
The condition is caused by a change in the HBB gene, a gene that gives the body instructions for making beta-globin, a protein found in hemoglobin.
In S,C disease, there are two changes to the HBB gene. One change causes an abnormal beta-globin called hemoglobin S (HbS). Another change causes an abnormal beta-globin called hemoglobin C (HbC).
The abnormal beta-globins cause red blood cells to break down more quickly and can block small blood vessels. This leads to many of the signs and symptoms of the condition.
- S,C disease is an autosomal recessive condition. Babies inherit the condition when each parent passes down a nonworking HBB gene to their baby. Only babies with two nonworking HBB genes—one from the mom and one from the dad—have this condition.
- People with one normal copy and one nonworking copy of the HBB gene are said to have a hemoglobin trait (sometimes also called being a carrier).
- People with a hemoglobin trait do not have or develop the condition. However, they may pass down a nonworking copy of the gene to their children.
- If two parents have a hemoglobin trait, meaning a nonworking copy of the HBB gene, they have a 1 in 4 chance of having a child with S,C disease.
- People with a hemoglobin trait for S,C disease often do not know they have the nonworking gene copy before having a child with the condition. In most cases, families have no history of the condition until the birth of a child with S,C disease.
- Parents who already have a child with S,C disease still have a 1 in 4 chance of having another child with S,C disease. This 1 in 4 chance stays the same for all future children.
- Genetic counselors and medical geneticists can help families learn about this condition and the chance of having children with it. Visit the National Society of Genetic Counselors to find a genetic counselor and the American College of Medical Genetics and Genomics to find a medical geneticist.
Treatment and Management
It is important to talk to your health care provider about which treatment(s) are best for your baby. The goal of treatment is to prevent the health problems caused by this condition.
Treatments may include the following:
- Daily dose of antibiotics to prevent repeated infections
- Medications to treat pain (analgesics)
- Blood transfusions in special circumstances
Children who receive early health care and treatment for S,C disease can have healthier lives than those who do not receive treatment.
Community-based organizations (CBOs) are local agencies that provide services, education, and support to families affected by sickle cell conditions like S,C disease. To find a CBO near you, please visit the Sickle Cell Disease Association of America’s list of member organizations.