- Knowledgebase: Information on Specific Illnesses
- Here you will find discussions of specific illnesses and their management.
- 67. Sickle Cell Anemia - Top
- Definition
An inherited, chronic blood disease in which the red blood cells become crescent shaped and function abnormally
Causes, Incidence and Risk Factors
Sickle cell anemia, which is caused by an abnormal type of hemoglobin (oxygen carrying pigment) called hemoglobin S, is inherited as an autosomal recessive trait. It occurs in people who have inherited hemoglobin S from both parents. If hemoglobin S is inherited from one parent, the offspring will have sickle cell trait and is usually without symptoms.
The disease occurs primarily in people of African Heritage, with 1 out of 400 African-Americans affected. The disease produces a chronic anemia which may become life-threatening when hemolytic crises (the breakdown of red blood cells) or aplastic crises (bone marrow fails to produce blood cells) occur. Repeated crises can lead to damage of the kidneys, lungs, bone, liver, and central nervous system. Acute painful episodes caused by blocked blood vessels and damaged organs may occur and last hours to days affecting the bones of the back, the long bones, and the chest.
The overall incidence is 8 out of 100,000 people. The manifestations of this disease are a result of the fragility and inflexibility of the sickle red blood cells. When exposed to dehydration, infection, and low oxygen supply, these fragile red blood cells assume a crescent shape causing red blood cell destruction and thickening of the blood. Sickle cell anemia can affect many other body systems. Symptoms of this disease are most severe during periods called "sickle cell crisis." Although this disease is inherited and present at birth, symptoms usually don't occur until after 4 months of age.
Symptoms
family history of sickle cell anemia
fatigue
breathlessness
rapid heart rate
delayed growth and puberty
susceptibility to infections
ulcers on the lower legs (in adolescents and adults)
jaundice
bone pain
attacks of abdominal pain
weakness
joint pain
fever
vomiting
Additional symptoms that may be associated with this disease:
urine, bloody (hematuria)
urination, excessive volume
thirst, excessive
penis pain
priapism
chest pain
decreased fertility
Signs And Tests
CBC
hemoglobin S screening test
hemoglobin electrophoresis
sickle cell test
This disease may also alter the results of the following tests:
urinary casts
TIBC
peripheral smear
hemoglobin; serum
ESR
bilirubin
Treatment
No cure is available for the disease. The objective of therapy is the comprehensive management and control of symptoms relating to crises. Bed rest to minimize energy expenditure and oxygen requirements during a crisis is recommended. Low oxygen levels result in acidosis which causes sickling.
Folic acid supplementation is a continuous therapy. Analgesics and adequate hydration are provided for acute, painful episodes. Blood transfusions may be given for aplastic or hemolytic crises, but should not be given routinely. A pneumococcal vaccine is given to prevent overwhelming infection in patients who have had a splenectomy. Electrolyte replacement is important, and hydration to dilute the blood is done via intravenous or oral fluid therapy.
Research is currently being done on a compound called hydroxyurea, which can induce some patients to produce a more normal blood protein and at least postpone sickle-cell attacks.
Parents should encourage their children to lead normal lives, but in order to decrease the occurrence of sickle cell crises, the following precautions should be considered:
A. To prevent tissue deoxygenation:
+ 1. avoid strenuous physical activity, especially if the spleen is enlarged.
+ 2. avoid emotional stress
+ 3. avoid environments of low oxygen content (high-altitudes, non-pressurized airplane flights)
+ 4. avoid known sources of infection
B. To promote hydration:
+ 1. recognize signs of dehydration
+ 2. avoid excess exposure to the sun
+ 3. provide access to fluids at home and when away from home
C. To avoid sources of infection:
+ 1. Keep child properly immunized as recommended by the health care provider.
+ 2. Consider having the child wear a Medic Alert Bracelet.
+ 3. Share above information with teachers and other caretakers as appropriate.
+ 4. Be aware of the effects that chronic, life-threatening illnesses can have on siblings, marital relationships, parents, and the child.
Expectations (Prognosis)
Death from organ failure frequently occurs between the ages of 20 and 40.
Complications
recurrent aplastic and hemolytic crises
multisystem disease
papillary necrosis (tissue death) of the kidney
removal of the spleen (splenectomy) if the spleen has atrophied.
Calling Your Health Care Provider
Call your health care provider if acute painful crises occur or at the first sign of any infection.
Prevention
Genetic counseling is recommended for carriers of the trait (about 1 in 12 African Americans has sickle cell trait). Prompt treatment of infections, adequate oxygenation, and maintaining normal hydration status may prevent sickling of red blood cells.
Prenatal diagnosis is now possible for couples at risk of producing a child with sickle cell anemia.
- Updated: March 5, 2001
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