Sickle Cell Anemia

What is sickle cell anemia?

Sickle cell anemia is the most severe type of sickle cell disease, an inherited blood disorder. In sickle cell anemia, you inherit a genetic mutation (change) that causes abnormal C-shaped or sickle-shaped red blood cells. Healthcare providers may call these cells “sickled cells.”

Normal red blood cells are round flexible disks. They slide through your blood vessels, carrying oxygen to your organs and tissues. Sickled cells are stiff and sticky and get stuck in your blood vessels instead of flowing throughout your body. Sickled cells also break apart and die more quickly than normal red blood cells. As a result, sickle cell anemia affects your red blood cell supply, so you develop severe anemia (low red blood cell levels).

Complications of sickle cell anemia can be life-threatening. In the past, babies born with this condition rarely lived to be adults. Now, thanks to early detection and new treatments, more people live into their 50s.

How common is sickle cell anemia?

Experts estimate that sickle cell anemia affects at least 100,000 people in the U.S. It affects more people who are Black than people who are white. Experts estimate that 1 in 365 people who are Black carry the genetic mutation that causes the condition. It may also affect people with southern European, Middle Eastern or Asian Indian ancestry.

What are the symptoms of sickle cell anemia?

Common symptoms include:

• Fatigue from anemia: Babies with sickle cell anemia may seem unusually fussy and irritable.
• Frequent infections: The condition affects your spleen, which weakens your immune system so you’re more likely to develop infections. However, because of the widespread use of preventive antibiotics and immunizations, the risk of developing infections is now greatly reduced.
• Pain: Sickle cell anemia causes tissue damage because your tissues don’t get enough oxygen. Tissue damage hurts, so you may have pain in your arms, legs, chest and back. It may start as an ache that gets worse or come on suddenly, causing excruciating pain.
• Painful swelling in hands and feet: This is one of the first symptoms of sickle cell anemia in babies. Sickled cells get stuck in babies’ blood vessels and keep blood from flowing to their hands and feet.
• Yellow-colored eyes and skin from jaundice: Your liver filters red blood cells (among other things). In sickle cell anemia, fast-dying sickled cells release bilirubin that builds up in your system to cause jaundice.

Sickle cell anemia symptoms typically start when babies are 6 to 9 months old. Symptoms change over time as your body makes more abnormal (sickled) cells.

What causes sickle cell anemia?

Sickle cell anemia happens when you inherit genetic mutations (changes) that affect the HBB gene. This gene gives instructions on how to make beta-globin, which is part of your hemoglobin protein. Hemoglobin helps your red blood cells to carry oxygen throughout your body.

You may be born with sickle cell anemia if you inherit one type of changed gene from both of your biological parents. Other forms of sickle cell disease occur when you inherit two different changed genes, one from each biological parent. Healthcare providers may call this a variant genetic mutation (change).

What are the complications of this condition?

Sickle cell anemia can cause serious and sometimes life-threatening complications. For example, people with sickle cell anemia often need emergency medical care or are admitted to the hospital because they experience complications like acute chest syndrome (ACS) or vaso-occlusive crisis (VOC).

Other complications of sickle cell anemia include:

• Chronic kidney disease, from lack of oxygen that causes tissue damage.
• Detached retinas, if sickled cells block blood vessels in your retina.
• Priapism (painful erections), from blocked blood vessels in your penis.
• Splenic sequestration, if sickled cells are stuck in your spleen and affect blood flow. Splenic sequestration often causes acute anemia.
• Stroke, which can happen to anyone with sickle cell anemia, including babies (pediatric stroke).

Acute chest syndrome (ACS)

Acute chest syndrome (ACS) is the most common complication of sickle cell anemia. It’s also the most common cause of death and the second most common cause of hospital admission. It happens when sickled cells clump and clog blood vessels in your lungs. Symptoms include:

• Sudden chest pain.
• Cough.
• Fever.
• Trouble breathing.

Vaso-occlusive crisis (VOC)

This is when sickled cells block your blood vessels (a vaso-occlusive episode). Healthcare providers may call this condition an “acute pain crisis.” In VOC, you can have excruciating pain that affects your arms, legs, lower back and belly.

Providers sometimes call VOC “the invisible illness.” Often, pain is the only symptom VOC causes. People can’t point to an injury or an illness. They just hurt.

Opioid medication is the only treatment to ease vaso-occlusive crisis. Studies show sickle cell anemia carries a stigma linked to people’s need for opioid medication to manage VOC. Living with that stigma can lead to depression and anxiety.

Other studies show people who are members of racial minorities receive less pain medication and must wait longer to receive pain medication than people who are white. Combined, these stigmas are an added challenge to living with sickle cell anemia.

How is sickle cell anemia diagnosed?

Healthcare providers diagnose sickle cell anemia by doing a physical examination that may include feeling your spleen or liver. They’ll ask about your symptoms, particularly pain in your arms, legs or belly. They may ask about your medical history, including infections. They may order the following tests:

• Complete blood count (CBC): CBCs include specific tests to check on your red blood cells.
• Hemoglobin electrophoresis: Also known as high-performance liquid chromatography, this test analyzes your hemoglobin to find and measure the abnormal hemoglobin that causes sickle cell anemia.
• Genetic tests: Your provider may order tests to see if you have the genetic changes (mutations) that cause sickle cell anemia.

How is sickle cell anemia treated?

Treatment for sickle cell anemia depends on your symptoms and your overall health. For example, if you have severe complications like acute chest syndrome, frequent acute pain crises or stroke, your provider may recommend an allogeneic stem cell transplant. This procedure is the only cure for sickle cell anemia.

Other sickle cell anemia treatments are blood transfusions, antibiotics to treat infections and medications that ease specific symptoms. Those medications include:

• Hydroxyurea (Droxia^®, Hydrea^®, Siklos^®, Mylocel^®): Hydroxyurea is an anticancer drug. It’s treatment for infants aged 6 to 9 months, children and adults. It may reduce how often you have serious complications and ease anemia symptoms.
• Voxelotor (Obryta^®): Voxelotor keeps red blood cells from becoming sickled cells. It’s treatment for children age 4 and older.
• L-glutamine therapy (Endari^®): This medication, which is a treatment for children age 5 and older and adults, keeps sickled cells from becoming even more abnormal.
• Crizanlizumab-tmca (Adakveo^®): This reduces how often you may have VOC/acute pain crisis. It’s treatment for people age 16 and older.

Can sickle cell anemia be prevented?

Sickle cell anemia is an inherited disorder that you can’t prevent. You can have a blood test to find out if you have the genetic change that causes sickle cell anemia.

Starting in 2006, all babies born in the U.S. have sickle cell anemia tests right after they’re born. Early diagnosis and treatment are why fewer babies and young children born in the United States die of sickle cell anemia.

What can I expect if I have sickle cell anemia?

For most people, sickle cell anemia is a chronic illness. That means they’ll need medical care and support all their lives. Sickle cell anemia symptoms can be mild, moderate or so severe that they’re life-threatening. Everyone’s situation is a bit different, so ask your healthcare provider what you can expect. They know your overall health and how sickle cell anemia affects you, so they’re your best source of information.

Does sickle cell anemia get worse with age?

As you get older, you may develop different and more serious medical problems that happen when organ tissues don’t receive enough oxygen. People with sickle cell anemia are at increased risk for stroke and lung, kidney, spleen and liver damage.

What is the life expectancy for someone who has sickle cell anemia?

Thanks to early diagnosis and treatment to ease complications, people with sickle cell anemia may live into their 50s. Some people with the disease may live much longer. If you have questions about how long you may live with sickle cell anemia, ask your healthcare provider. They’ll be glad to explain what you might expect.

How do I take care of myself?

New treatments are helping people with sickle cell anemia live longer and with better quality of life. The U.S. Centers for Disease Control and Prevention (CDC) has the following suggestions for living well with sickle cell anemia:

• Find specialized medical care: Managing sickle cell anemia requires a multidisciplinary team of healthcare providers who specialize in blood disorders.
• Get regular checkups: Regular health checkups with your primary provider care may head off serious medical complications. Having a relationship with your healthcare provider who understands your situation may make it easier to get help if you have an acute pain crisis.
• Consider pain management: Pain is a constant complication of sickle cell anemia. It can be chronic — meaning you have pain for three to six months – or acute. Pain management specialists can recommend ways to help manage pain.
• Get mental health support: Unfortunately, there are stigmas associated with sickle cell anemia that may cause depression or anxiety. Talk to your healthcare provider if you’re struggling with emotions related to feeling stigmatized. They can recommend resources to help you. More than that, they may be able to advocate for you by educating their peers about sickle cell anemia complications and symptoms.
• Prevent infections: Talk to your healthcare provider about vaccinations and take steps to protect yourself from infection.
• Manage your environment: People who have sickle cell anemia need to keep a balanced body temperature to avoid VOC/acute pain crises by avoiding situations where they get too hot or too cold.
• Look for clinical trials: Healthcare providers and researchers are constantly testing new treatments. Joining a clinical trial may be a way to obtain new medication and treatment. Ask your healthcare provider for help finding a clinical trial.

When should I see my healthcare provider?

You should contact your provider if your symptoms are getting worse or if you have changes in your body that could be new symptoms.

When should I go to the emergency room?

Sickle cell anemia may cause serious medical conditions. Go to the emergency room if you have:

• Anemia symptoms like extreme fatigue, shortness of breath or irregular heartbeat.
• Fever of more than 101.3 degrees Fahrenheit (or 38.5 degrees Celsius).
• Chest pain.
• Cough.

The condition also increases your risk of having a stroke. A stroke is a medical emergency. If you have the symptoms below or are with someone who’s having symptoms, call 911 or emergency services right away:

• Balance or coordination issues.
• Blurred or double vision.
• Confusion.
• One-sided weakness or paralysis.
• Slurred speech.