What Is Sickle Cell Disease?
- Healthy red blood cells are round and they move through small blood vessels carrying oxygen to all parts of the body.
- In SCD, the red blood cells become hard and sticky and look like a C-shaped farm tool called a “sickle”.
- Sickle cells die early, which causes a constant shortage of red blood cells.
What causes SCD?
- Point mutation in beta globulin gene changing Glu→Val at position 6 in the Beta Globin chain of hemoglobin, results in Hb S.
Who is affected by sickle cell disease?
- SCD affects millions of people throughout the world and is particularly common among those whose ancestors come from sub-Saharan Africa; regions in the Western Hemisphere; Saudi Arabia; India; and Mediterranean countries such as Turkey, Greece, and Italy.
What health problems does sickle cell disease cause?
- Sickle cells can get stuck in small blood vessels and block the flow of blood and oxygen to organs in the body. These blockages cause repeated episodes of severe pain, organ damage, serious infections, or even stroke.
- Following are some of the most common complications of SCD:
“Pain Episode” or “Crisis”: Sickle cells don’t move easily through small blood vessels and can get stuck and clog blood flow. This causes pain that can start suddenly, be mild to severe, and last for any length of time.
“Infection”: People with SCD, especially infants and children, are more likely to experience severe symptoms of infections such as flu, meningitis, and hepatitis.
“Hand-Foot Syndrome”: Swelling in the hands and feet, often along with a fever, is caused by the sickle cells getting stuck in the blood vessels and blocking the blood from flowing freely through the hands and feet.
“Eye Disease”: SCD can affect the blood vessels in the eye and lead to long term damage.
“Acute Chest Syndrome (ACS)”: Blockage of the flow of blood to the lungs can cause acute chest syndrome. ACS is similar to pneumonia; symptoms include chest pain, coughing, difficulty breathing, and fever. It can be life threatening and should be treated in a hospital.
“Stroke”: Sickle cells can clog blood flow to the brain and cause a stroke. A stroke can result in lifelong disabilities and learning problems.
How to investigate for sickle cell disease?
- Complete Blood Picture: Low hemoglobin
- HPLC/ Hb electrophoresis: Diagnostic test which quantifies different types of hemoglobin.
- Genetic testing: To detect the defective gene.
How is sickle cell disease treated?
- The goals of treating SCD are to relieve pain and to prevent infections, eye damage, and strokes.
- Parental education about the disease and information about preventing complications.
- There is no single best treatment for all people with SCD. Treatment options are different for each person depending on the symptoms. Treatments can include receiving blood transfusions, maintaining a high fluid intake (drinking 8 to 10 glasses of water each day), receiving IV (intravenous) therapy (fluids given into a vein), medications to help with pain and Folic acid and Calcium to support the high turnover of the bone marrow.
- Prevention of infection by prophylactic pencillin.
- Regular immunisation; additional vaccines against encapsulated organisms especially pneumococcus.
- A medicine Hydroxyurea is recommended for many SCD patients. It reduces the number of painful episodes and the recurrence of ACS. It also reduces hospital stays and the need for blood transfusions among adults who have SCD.
- HSCT: To date, the only cure for SCD is a bone marrow or stem cell transplant. It is indicated in CNS crisis, chest crisis or pain crisis not responding to regular transfusions. Hematology, Oncology and BMT department at Rainbow Children Hospital, provides medical management and stem cell transplant therapy for children with sickle cell disease.
Antenatal diagnosis:
- Sickle cell disease can be diagnosed in an unborn baby by sampling CVS or amniotic fluid surrounding the baby in the mother’s womb (amniotic fluid). This is useful to prevent the birth of a second child with sickle cell disease in the family when we know the index genetic mutation.
- Active family screening and extended family members screening will help in controlling the disease
Dr. Sirisha Rani, MD (Peds) (PGIMER), DNB, MRCPCH (UK), Fellow in Pediatric Hemato, Oncology and Bone Marrow Transplantation (UK), Pediatric Hematologist & Oncologist
