Sickle cell anemia is also called sickle cell disease or hemoglobinosis S . This form of chronic, hereditary anemia is characterized by, among other things, very painful attacks. It is relatively widespread and affects mainly black people: its prevalence is between 0% and 40% in Africa and 10% in African Americans. Currently in the United States, 1 in 500 African American infants has sickle cell disease; the prevalence is 1 in 1,100 to 1,400 for Hispanic children. People from the Caribbean and South America are also at high risk.
This disease is genetic: it is linked to the presence of abnormal hemoglobin genes that produce a non-functional hemoglobin protein, called hemoglobin S. This protein deforms the red blood cells into a crescent or sickle shape (hence the name sickle cell) and causes them to die prematurely. These deformed red blood cells are also called sickle cells. This deformation makes the red blood cells fragile. They are quickly destroyed. In addition, their unusual shape makes it more difficult for them to pass through the small blood vessels. Sometimes they block the blood supply to certain organs and cause circulatory accidents.
The accelerated destruction of red blood cells eventually leads to hemolytic anemia – that is, anemia caused by abnormally rapid destruction of red blood cells. In addition, the abnormal shape of the red blood cells can create blockages in the capillaries and cause a variety of problems related to poor blood flow. Fortunately, people with sickle cell disease can prevent complications and attacks to some extent. They also live longer than before (Disease Course).
The presence of hemoglobin S is due to a genetic defect in the gene responsible for making hemoglobin. Thousands of years ago, at a time when malaria was killing many people, people with this genetic defect had a better chance of survival because hemoglobin S prevents the malaria parasite from entering the red blood cells. Since this inherited characteristic was an advantage for the survival of the species, it was maintained. Nowadays, it has of course become a handicap now that malaria is well treatable.
For a child to have sickle cell anemia, both parents must have passed on the hemoglobin S gene. If only one parent passes on the gene, the child will also carry the offending gene, but will not have the disease. However, the child could pass on the gene to others.
Course of the disease
The disease appears around the age of six months and manifests itself differently from one patient to another. Some have only mild symptoms and experience less than one attack per year, during which time symptoms are exacerbated. In the past, this disease was often fatal in children under the age of five. Although the death rate remains high in this age group, treatments now allow patients to live at least into adulthood.
There are many complications. Among the main ones are the following:
- Vulnerability to infections. Bacterial infections are a major cause of complications in children with sickle cell anemia. This is why antibiotic therapy is often given to them. Sickle cells damage the spleen, which plays a vital role in infection control. In particular, pneumococcal infections, which are very frequent and dangerous, are to be feared. Adolescents and adults should also protect themselves against infections.
- Growth and puberty delayed, constitution frail in adults. This phenomenon is caused by a lack of red blood cells.
- Painful crises. They usually appear on the limbs, abdomen, back or chest, and sometimes on the bones. They are linked to the fact that sickle cells block blood flow in the capillaries. Depending on the case, they can last from a few hours to several weeks.
- Visual disturbances. When blood circulates poorly in the tiny vessels that surround the eyes, it damages the retina and can therefore lead to blindness.
- Gallstones. The rapid destruction of sickle cells releases a substance associated with jaundice, bilirubin. However, if the bilirubin level rises too much, gallstones can form. Moreover, jaundice is one of the symptoms associated with this form of anemia.
- Edema of the hands and feet or hand-foot syndrome. Again, this is a consequence of circulatory obstruction caused by abnormal red blood cells. It is often the first sign of illness in infants and in many cases is associated with fever attacks and pain.
- Leg ulcers. Since the blood circulates poorly to the skin, the skin cannot receive the necessary nutrients. One after the other, skin cells die and open wounds appear.
- Priapism. These are painful and prolonged erections which are explained by the fact that blood accumulates in the penis without being able to flow back because of the sickle cells. These prolonged erections end up damaging the tissues of the penis and lead to impotence.
- Acute chest syndrome ( acute chest syndrome ). Its manifestations are as follows: fever, cough, expectoration, pain in the chest, difficulty in breathing (dyspnea), lack of oxygen (hypoxemia). This syndrome results from a lung infection or sickle cell cells trapped in the lungs. It seriously endangers the life of the patient and must be treated urgently.
- Organic lesions. Chronic lack of oxygen damages nerves as well as organs such as the kidneys, liver or spleen. This type of problem sometimes causes death.
- Stroke. By blocking circulation to the brain, sickle cells can cause a stroke . About 10% of children with the disease have suffered from it.
Symptoms of sickle cell anemia
- Pain in the limbs, abdomen, back or chest – and sometimes in the bones. This is the main symptom in both children and adults.
- Vulnerability to infection.
- Edema creating swelling in the feet and hands in infants. This may be the first symptom of the disease.
- Those related to low red blood cell count that are common to other types of anemia: pale skin, fatigue, weakness, dizziness, rapid heart rate, etc.
- Those related to the destruction of red blood cells: a yellow coloring of the mucous membranes of the eyes and skin (in Blacks, this symptom is only seen in the eyes) and dark urine.
- Vision problems, up to and including blindness.
- Those of the acute chest syndrome: fever, cough, sputum, respiratory discomfort, lack of oxygen.
People and risk factors for sickle cell anemia
People at risk
- The risk scale by region reads as follows 1 :
– Are at very high risk: inhabitants of intertropical Africa or parts of India.
– Are at high risk: inhabitants of the West Indies, South America, black Americans (another source indicates that in the United States, the disease is also very common among Hispanics and Native Americans).
– Are at medium risk: North Africans, Greeks or Sicilians.
– Are low risk: Portuguese, Israelis and Turks.
- People whose two parents are carriers of the hemoglobin S gene. The risk profile of the child is as follows:
– One in four chance of having the disease;
– Two out of four chances of being a carrier of a faulty gene;
– One in four chance of being neither affected nor carrying the faulty gene.
Seizures can occur spontaneously, but can also be triggered by the following factors
- Alcohol consumption.
- Lack of oxygen (as in airplanes and at high altitudes).
- Extreme temperature (cold or hot).
Prevention of sickle cell anemia
At present, this form of anemia cannot be prevented, but it is anticipated that gene therapy will be possible in the future. For the time being, however, it is recommended that genetic testing be done before having children if a family member has this disease or if you are black.
Measures to prevent seizures
The Sickle Cell Disease Information and Prevention Association (Specialty Sites) makes the following recommendations to reduce the number of seizures:
- Prevent infections: impeccable body and dental hygiene, antibiotic therapy and systematic vaccination from birth.
- Pay attention to your temperature.
- If the temperature is equal to 38°C, you must quickly go and see a doctor.
- Avoid dehydration, as this can lead to seizures and increased blood viscosity. Therefore, drink plenty of water: about three liters a day. This is especially important in the summer and in cases of diarrhea, fever or vomiting. In summer, it is also important to reduce exposure to the sun.
- Make sure you never run out of oxygen. This means avoiding:
- travel in unpressurized or poorly pressurized airplanes;
- Poorly ventilated areas;
- Excessive physical exertion;
- prolonged standing.
- Eat very well. Dietary deficiencies make anemia worse and increase susceptibility to infection. Therefore, make sure that the diet provides an increased intake of folate, iron and protein.
- Check for signs of rapid red blood cell destruction: yellow eyes and skin (jaundice), dark urine, cold sores or fever blisters.
- Be careful not to interfere with the circulation of the blood, as this can cause swelling of the extremities or pain, among other things. It is therefore best to avoid wearing tight clothing, crossing your legs, etc.
- It is also important to see a doctor regularly – especially to detect eye abnormalities early enough to prevent blindness.
- Have a healthy lifestyle. In addition to eating well, it is also important to rest well and avoid unnecessary stress.
Medical treatments for sickle cell anemia
Supplementation. Daily supplementation with folic acid (or vitamin B9) is necessary to promote the production of new red blood cells.
Hydroxyurea. Originally a drug for leukemia, it was also the first drug found to be effective in treating sickle cell disease in adults. Since 1995, it has been known to reduce the frequency of painful attacks and acute chest syndrome. Patients who use this drug also have less need for transfusions.
In addition, the combined use of hydroxyurea and erythropoietin may increase the effectiveness of hydroxyurea. Synthetic erythropoietin injections are used to stimulate red blood cell production and relieve fatigue. However, little is known about its long-term impact, particularly because of the risk of a dangerous drop in blood cell levels. Its use in sickle cell disease children is still under study.
Blood transfusions. By increasing the number of red blood cells in circulation, transfusions prevent or treat certain complications of sickle cell disease. In children, they help prevent recurrence of strokes and enlargement of the spleen.
Repeat transfusions are possible, but treatment to reduce blood iron levels is required.
A variety of surgical procedures can be performed as problems arise. For example:
- Treat certain types of organ damage.
- Removing gallstones.
- Installing a hip prosthesis in case of hip necrosis.
- Prevent eye complications.
- Skin grafts to treat leg ulcers if they do not heal, etc.
Bone marrow transplants are sometimes used in children with very severe symptoms. Such an operation can cure the disease, but there are many risks involved, not to mention the need to find a compatible donor from the same parents.
N.B. Several new treatments are being studied. This is particularly the case for gene therapy, which would make it possible to inactivate or correct the faulty gene.
To prevent complications
Incentive spirometer. To avoid lung complications, those with severe back or chest pain may use an incentive spirometer, a device that helps them breathe more deeply.
Antibiotics. Because of the serious risks associated with pneumococcal disease in children with the disease, they are prescribed penicillin from birth to age six. This practice has greatly reduced mortality in this age group. Antibiotics will also be used to prevent infections in adults.
Vaccination. Sickle cell patients – children or adults – should be protected primarily against pneumonia, influenza and hepatitis. Routine vaccination is recommended from birth to age six.
In case of an acute attack
Analgesics. These are used to control pain in the event of an acute attack. Depending on the case, patients may be satisfied with over-the-counter painkillers or may be prescribed stronger ones.
Oxygen therapy. In the event of an acute attack or breathing problems, the use of an oxygen mask can make it easier to breathe.
Rehydration. In case of painful attacks, intravenous infusions can also be used.
Complementary approaches to sickle cell anemia
Zinc. It is known that an adequate intake of zinc is necessary for the proper functioning of the immune system. Zinc deficiency is common in people with sickle cell anemia, as the disease increases zinc requirements. A randomized clinical trial of 130 subjects followed for 18 months indicated that supplementation with 220 mg of zinc sulphate (capsules) taken three times daily may reduce the average number of infectious episodes and associated complications.8 A more recent three-year study of 32 subjects taking 50 mg to 75 mg of elemental zinc per day reached similar conclusions.9 Finally, supplementation with 10 mg of elemental zinc per day in children with sickle cell anemia is believed to result in better-than-average growth and weight gain.
Omega-3 fatty acids. There is some evidence that consumption of omega-3 fatty acids may help reduce the frequency of painful attacks typical of sickle cell anemia.5,12,13
Acupuncture. Two small studies suggest that acupuncture may help relieve pain in painful crises.3,4 One researcher reports that he achieved results when conventional means failed. The results were so dramatic that he used acupuncture in four other cases.4 See the Acupuncture fact sheet.
Vitamin C, vitamin E and garlic cocktail. According to a recent controlled clinical study involving 20 subjects, this treatment may be effective in sickle cell anemia because of its antioxidant effect.6 It reduces the formation of cells with high density and abnormal membranes. These tend to obstruct the blood flow and thus cause the typical pain associated with this phenomenon. In this study, 6 g of aged garlic, 4 g to 6 g of vitamin C and 800 IU to 1200 IU of vitamin E were used.
Homeopathy. Homeopathy may help relieve some symptoms, such as fatigue.10
Relief and support measures. Being part of a support group can be very helpful.
Applying moist heat to an affected area can help relieve pain.