Sickle cell disease, also known as sickle cell anemia, is a genetic disease caused by a defective amino acid in the hemoglobin molecule of red blood cells. As a result, red blood cells take on an abnormal "sickle" shape and can clog small arteries, resulting in severe pain and tissue damage. The abnormal blood cells are destroyed by the body, resulting in anemia.
Individuals born with two sickle cell genes (one each from their mother and father) will develop the disease. Individuals with only one sickle cell gene are carriers for the disease: They are not themselves affected under normal circumstances, but they can pass along the gene to their children. For this reason, all newborn babies are screened for the disease at birth.
- Pain in the hands and feet
- Chest pain
- Shortness of breath
- Elevated heart rate
- Jaundice (yellow discoloration of the skin)
- Priapism (prolonged erection) occurs in up to 40 percent of individuals
- Delayed growth or delayed puberty
- Leg ulcers
The disease occurs most often among people whose ancestry can be linked to sub-Saharan Africa, South and Central America, the Caribbean, India, and the Middle East and Mediterranean regions.
One study showed the disease to be about 300 times more common in African-Americans (approximately three per 1,000) than in Caucasians, and three times more common in Latinos than in Caucasians. Approximately one in 12 African-Americans carries a sickle cell gene.
Sickle Cell Disease: Diagnosis and Treatment
- Prenatal screening can be done if the fetus is at risk for sickle cell disease.
- At birth, screening is universally performed in all states.
- Blood testing reveals anemia and sickle-shaped red blood cells.
- In affected individuals, several types of diagnostic testing may be necessary throughout their lifetimes. These include ultrasounds of the head and neck to identify those at risk for stroke, routine eye examinations to check for chronic eye disorders, and chest X-rays to assess lung structure and function.
- Pain can be treated with analgesic medications (e.g., Tylenol, ibuprofen, and ketorolac), warm compresses, and hydration. In some cases, stronger pain medications, including narcotics (e.g., morphine), are required. In addition, complementary therapies, such as hypnosis, relaxation techniques, and biofeedback, may be helpful.
- Infection is the most common cause of death in patients with sickle cell disease. Antibiotics are often necessary when infection occurs, which may require hospitalization for intravenous delivery. The influenza and pneumococcus vaccines should routinely be used.
- Supplementation with folic acid should be taken in doses of 1 milligram daily. In addition, supplementation with magnesium may be helpful.
- Blood transfusions are commonly necessary to supply properly functioning red blood cells to increase oxygen-carrying capacity. In addition, several medications (e.g., hydroxyurea and erythropoeitin) may be used to improve the oxygen-carrying capacity of red blood cells.
- Stem cell transplantation and gene therapy are experimental, but hold promise for a cure in the near future.
Sickle Cell Disease: Nutritional Considerations
Patients with sickle cell disease have increased needs for calories and micronutrients (e.g., vitamins and minerals). A diet emphasizing fruits, vegetables, whole grains, and legumes will provide a greater proportion of essential nutrients than a typical Western diet, and appropriate supplementation (one to three times the recommended intakes for most essential nutrients) can prevent deficiency.
- A high-calorie, nutrient-dense diet: The average caloric intake of sickle cell patients is typically low, especially during flare-ups of the disease. As a result, children with sickle cell disease have impaired growth and significantly lower weight compared with unaffected individuals. A careful nutritional assessment and the addition of energy supplements are needed.
- Adequate fluid consumption to maintain hydration: Sickling of red blood cells increases when patients become dehydrated. Thus, it is important to maintain hydration by consuming adequate fluids. In some cases, hospitalization to receive intravenous fluids may become necessary.
- Vitamin and mineral supplementation: Blood levels of several vitamins and minerals are often low in individuals with sickle cell disease, including vitamin A and carotenoids, vitamin B6, vitamin C, vitamin E, magnesium, and zinc. This can result in a significant deficiency of antioxidants, which may increase the risk of disease flare-ups. Studies indicate that vitamin-mineral supplements of certain nutrients (vitamins C and E, zinc, and magnesium) or treatment with a combination of high-dose antioxidants can reduce the percentage of sickled red blood cells.
- Omega-3 fatty acid supplements: Supplementation with omega-3 fatty acids can improve the membranes of red blood cells and may decrease flare-ups of the disease. A small preliminary study indicated that omega-3 fatty acid supplementation with fish oil reduced the number of painful episodes requiring hospitalization. However, this finding has not yet been confirmed in controlled trials.