sickle cell disease


Also found in: Dictionary, Thesaurus, Medical, Legal, Acronyms.
Related to sickle cell disease: sickle cell trait, Sickle cell crisis

sickle cell disease

or

sickle cell anemia,

inherited disorder of the blood in which the oxygen-carrying hemoglobinhemoglobin
, respiratory protein found in the red blood cells (erythrocytes) of all vertebrates and some invertebrates. A hemoglobin molecule is composed of a protein group, known as globin, and four heme groups, each associated with an iron atom.
..... Click the link for more information.
 pigment in erythrocytes (red blood cells) is abnormal. This "hemoglobin-S" crystallizes in small capillaries, where the concentration of oxygen in the blood is low (but sufficient for normal hemoglobin), causing the red blood cells to assume distorted, sicklelike shapes. Linus PaulingPauling, Linus Carl
, 1901–94, American chemist, b. Portland, Oreg. He was one of the few recipients of two Nobel Prizes, winning the chemistry award in 1954 and the peace prize in 1962.
..... Click the link for more information.
 discovered the chemical abnormality of the hemoglobin molecule that causes the erythrocyte sickling in 1949.

The sickled red blood cells tend to clog small blood vessels, depriving the tissues they serve of blood and oxygen. Painful "crises" result, with symptoms depending on the site affected (e.g., joint and abdominal pain or kidney damage). Strokes or seizures can occur if the brain is affected. Lung infections resulting from the patient's disinclination to take painful deep breaths are a frequent complication. In addition, the sickled erythrocytes are fragile and subject to rupture and destruction, leading to hemolytic anemia (reduction of oxygen-carrying hemoglobin caused by premature destruction of red blood cells) and such symptoms as fatigue, jaundice, and headaches.

Treatment

There is no cure for the disease, but advancements in treatment have improved median survival to 42 years for men and 48 years for women. Cerebral hemorrhage or shock is the usual cause of mortality in children. Recent studies have indicated that regular blood transfusions can prevent strokes in children. Anemia is treated with folic acid. Sickle cell crises may be treated with intravenous hydration, pain medication, antibiotics, oxygen, and transfusions. Hydroxyurea, formerly used as a cancer treatment, has been helpful to many adults with the disease, lessening the frequency and severity of crises. New drugs for reducing the severity of crises are being tested as well. One acts as a lubricant, allowing sickled cells to flow more easily through tiny vessels. The other helps to prevent tissue deprived of blood from dying during a crisis.

Incidence

The disease occurs mainly in persons of sub-Saharan African, especially W African, origin, but it also occurs in persons of Mediterranean, Middle Eastern, and Indian origin. The mutation may at one time have had an advantageous effect; those who have the sickle cell trait have a higher survival rate in malaria-infested zones.

Under normal circumstances the disease occurs only in those patients who inherit the gene for the abnormal hemoglobin from both parents. This so-called homozygous form of the disease occurs in 1 in 400 African Americans. About 8% of African Americans have sickle cell trait; that is, they are heterozygotes, usually symptomless carriers who have inherited a normal hemoglobin gene from one parent and hemoglobin-S from the other. There are also intermediate forms of the disease that result when a gene for hemoglobin-S is inherited from one parent and a gene for any of several other abnormal kinds of hemoglobin is inherited from the other. Genetic screening (see genetic testinggenetic testing,
medical screening for genetic disorders, by examining either a person's DNA directly or a person's biochemistry or chromosomes for indirect evidence. Testing may be done to identify a genetic disorder a person has, whether the disorder is already evident or not,
..... Click the link for more information.
) is recommended for prospective parents at risk of passing on the disease. If both parents are carriers (i.e., have sickle cell trait), then each child has a one in four chance of having sickle cell disease.

References in periodicals archive ?
Study patients on Xyndari also had fewer occurrences of acute chest syndrome, a life-threatening complication of sickle cell disease (8.
Its long past time we start treating sickle cell disease as the serious and debilitating illness it is and allocate the necessary resources to monitor, research, and treat it, Booker added.
For thalassemia, the occurrence is much higher in the Middle East compared with the US, and for sickle cell disease it is slightly higher, especially in Saudi Arabia and the United Arab Emirates," Dr Hanna said.
Mary Cataletto from Stony Brook University's school of medicine said, "Management of acute chest syndrome is a major challenge for physicians and other healthcare providers caring for children with sickle cell disease.
When coupled with corrected sickle cell disease specific iPSCs, these tools could one day provide a functional cure for the disorder.
Sickle cell disease (SCD) is an inherited blood disorder caused by a genetic mutation in the beta-chain of hemoglobin, leading to formation of abnormal hemoglobin known as sickle hemoglobin, or HbS.
While the mortality rate for sickle cell disease in children decreased 3 percent each year in a study from 1979 to 2005, the mortality rate for adults with the disease increased by 1 percent each year.
Population estimates of sickle cell disease in the U.
The report reviews pipeline therapeutics for Sickle Cell Disease by companies and universities/research institutes based on information derived from company and industry-specific sources
In a study of perceptions of 1,772 children with sickle cell disease compared with a parent/caregiver, both children and parent/caregiver reported that school functioning decreased in response to asthma and pain (Dampier et al.
MATERIAL AND METHODS: This prospective study was conducted from September 2009 to September 2011 in 100 patients of sickle cell disease diagnosed by history and by investigations, who attended the surgical OPD and admitted in Dr.
A review of the Sickle Cell Disease products under development by companies and universities/research institutes based on information derived from company and industry-specific sources

Full browser ?