Understanding Sickle Cell Disease: Causes, Symptoms, and Treatment

Published by Daniela Hermelin, M.D. on Thursday, June 22, 2023 in Blog

What is Sickle Cell Disease? 

Sickle Cell Disease is a genetic blood disorder that affects the hemoglobin in red blood cells. Hemoglobin is responsible for carrying oxygen throughout the body, but in people with Sickle Cell Disease, the hemoglobin becomes misshapen and rigid, causing the red blood cells to become stuck in small blood vessels. This can lead to a range of symptoms and complications, including pain, organ damage, and increased risk of infections. Sickle Cell Disease is a lifelong condition that requires ongoing management and treatment.

What Causes Sickle Cell Disease? 
 

Sickle cell disease is caused by a mutation in the gene responsible for producing hemoglobin, the protein that carries oxygen in red blood cells. The mutation results in a substitution of a single amino acid in the hemoglobin molecule, leading to the formation of abnormal hemoglobin called HbS. This mutation is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to develop sickle cell disease. Individuals who inherit only one copy of the mutated gene are carriers and generally do not exhibit symptoms of the disease, but they can pass the gene on to their children.

HbS can cause deformed red blood cells when it is deoxygenated, as the abnormal hemoglobin molecules stick together and form long chains, distorting the shape of the red blood cells into a sickle-like shape. Additionally, conditions such as low oxygen levels, dehydration, or increased acidity can further promote the sickling process, leading to the characteristic deformation of red blood cells in sickle cell disease.  Sickle cell disease causes pain primarily because of the obstruction of blood flow in the small blood vessels by the deformed sickle-shaped red blood cells. When these cells become stuck in the blood vessels, they impede the normal circulation of oxygen, leading to tissue damage and triggering intense pain. This blockage can occur in various parts of the body, including bones, joints, and organs. Additionally, the sickle cells themselves can release substances that promote inflammation and further contribute to the pain experienced by individuals with sickle cell disease. The frequency and intensity of pain episodes, known as sickle cell crises, can vary among individuals and may be influenced by factors such as physical exertion, dehydration, infection, and low oxygen levels.

Symptoms of Sickle Cell Disease
 

The clinical symptoms of sickle cell disease can vary in severity and may include episodes of severe pain called sickle cell crises, fatigue, anemia, jaundice (yellowing of the skin and eyes), shortness of breath, delayed growth and development in children, frequent infections, and complications such as organ damage, stroke, acute chest syndrome, and priapism (persistent painful erection in males). Other symptoms can include swelling in the hands and feet, vision problems, gallstones, and ulcers on the legs. People with Sickle Cell Disease are also at increased risk for infections, stroke, and other complications. It's important to work closely with a healthcare provider to manage symptoms and prevent complications. Children with sickle cell disease can develop the same symptoms as adults, but they also can exhibit delayed growth and development. Regular medical care and appropriate management strategies are essential in addressing these symptoms and improving the quality of life for both adults and children with the condition.
 

Diagnosis and Treatment of Sickle Cell Disease
 

Sickle cell disease is typically tested using a combination of laboratory tests and genetic testing. Laboratory tests involve analyzing a blood sample to examine the presence of abnormal hemoglobin and determine the hemoglobin type. The most common test is called hemoglobin electrophoresis, which separates different types of hemoglobin to identify the presence of HbS, the abnormal hemoglobin associated with sickle cell disease. Genetic testing can be performed to identify specific mutations in the HBB gene and confirm the diagnosis of sickle cell disease. This can be done through techniques like polymerase chain reaction (PCR) or DNA sequencing.

Testing may also involve screening newborns for sickle cell disease as part of routine newborn screening programs. Newborn screening for sickle cell disease is a routine test performed shortly after a baby's birth. The screening aims to detect infants who may have sickle cell disease or carry the sickle cell trait. Early identification allows for timely intervention and medical management to prevent complications and provide appropriate care. If the screening result is positive, further confirmatory tests are conducted to determine the presence of sickle cell disease or carrier status. Newborn screening programs have been implemented in many countries to ensure early detection and appropriate support for infants with sickle cell disease.

Early diagnosis is crucial in managing the condition effectively and providing appropriate care and support to individuals with sickle cell disease.

The most common strategies of treating sickle cell disease focus on managing symptoms, preventing complications, and improving overall quality of life. These include:

1. Blood transfusions: Regular blood transfusions can be used to increase the number of healthy red blood cells and improve oxygen delivery in individuals with severe sickle cell disease. This can help prevent complications and improve overall well-being.
2. Hydroxyurea: Hydroxyurea is a medication that can help reduce the frequency and severity of pain crises and other complications in sickle cell disease. It works by increasing the production of fetal hemoglobin, which can prevent the sickling of red blood cells.
3. Pain management: Painful episodes, known as vaso-occlusive crises, are a common symptom of sickle cell disease. Pain medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, and other analgesics, are often used to provide relief during these episodes.
4. Hematopoietic stem cell transplantation (HSCT): For severe cases of sickle cell disease, HSCT may be considered as a potential cure. This procedure involves replacing the patient's diseased bone marrow with healthy stem cells from a compatible donor.
5. Supportive care: Comprehensive care, including regular check-ups, monitoring of organ function, nutritional support, and psychosocial support, plays a vital role in managing sickle cell disease. This can help address complications, promote overall well-being, and enhance the quality of life for individuals with the condition.

Treatment plans for sickle cell disease are individualized based on the specific needs and circumstances of each patient. Close collaboration with healthcare providers specializing in sickle cell disease is essential for developing an effective and personalized treatment approach.

Red4Life Program 
 

ImpactLife's Red4Life program is a transformative initiative that has changed the way blood donation impacts communities. With its comprehensive approach, Red4Life provides by promoting regular donors, organizing mobile drives, and fostering a culture of giving. The Red4Life program diversifies the blood donor base and increases the number of blood products available to effectively serve patients with Sickle Cell Disease. Donors whose blood is tested and identified as an appropriate antigen match for patients with Sickle Cell Disease are invited to become a Red4Life donor. Red4Life's commitment to enhancing public awareness and education has contributed to increased donor participation and a strengthened sense of civic responsibility. Through its efforts, ImpactLife's Red4Life program continues to create a profound and lasting impact on countless lives.



References

National Heart, Lung and Blood Institute 

Center for Disease Control and Prevention