Sickle Cell Disease

SICKLE CELL DISEASE :: SCHAF

Sickle Cell Disease is a family of inherited disorders of the blood, which results in anaemia and, with its numerous complications, shortens the life of the affected individuals.

The most severe form is the Sickle Cell Anaemia with haemoglobin genotype SS.

SCD is inherited from both parents, irrespective of religion, political, financial, or social class, education, or previous occurence in the family.

SCD is affected by Malaria and also by the types of genes surrounding the sickle gene (Haplotype).

SCD complications include:
• Anaemia
• Jaundice
• Pain episodes
• Delayed growth
• Infections
• Bones damage
• Leg Ulcers
• Lung blockage
• Kidney
• Priapism
• Stroke

SCD has a wide variety of severity from the very severe to those with mild complications, living a longer and fairly stable life.

Another in the family of SCD is Sickle cell haemoglobin C Disease (HbSC)

SICKLE CELL TRAIT

Sickle Cell trait (AS) is the inheritance of only one (S) gene from one parent and a normal (A) gene from the other parent.

Individuals with this genotype are perfectly healthy, AS does not carry the disease but it can transmit it to their offspring if married to another AS, SC or SS.

MYTHS AND MISCONCEPTIONS ABOUT SICKLE CELL DISEASE

Sickle cell disease is an African disease, affecting only people in Africa and their descendants.

False: SCD is widespread, affecting many races and ethnicities. SCD also commonly affects Hispanics, Asians, Indians and people of Mediterranean and Middle Eastern descent.

Sickle cell disease is so named because of the sickled shape of the red blood cells.

False: Although the red blood cells in a person with sickle cell disease are sickled in shape, sickle cell disease is actually named after a C-shaped farming tool called a “sickle”.

Sickle cell skips a generation.

False: Sickle cell is an autosomal recessive disorder. This means that both parents must carry the sickle allele (gene) to have a child with sickle cell disease. To carry the gene, the parents could themselves have sickle cell disease, or be carriers (have sickle cell trait, but not sickle cell disease). For more information, see the “About Sickle Cell” page, and watch the video “How is sickle cell disease inherited?”

Sickle cell is a communicable disease.

False: A person cannot “catch” sickle cell disease from another person, like one would catch a cold or the flu. SCD can ONLY be inherited from parents. To inherit SCD, both parents must carry the sickle cell trait. For more information, see the “About Sickle Cell” page, and watch the video “How is sickle cell disease inherited?”

Sickle cell patients do not grow to adulthood.

False: In the past, sickle cell patients often died from organ failure, infection and other complications at an early age. Today, people with sickle cell disease can live into their 50s and beyond, thanks to modern medicine. The most recent in-depth study on mortality and causes of early death in sickle cell disease was published in 1994. This study determined average life expectancy to be 42 years for males and 48 years for females in the United States (Platt et al., 1994). In the UK, the current estimate is between 53 and 60 years of age. That is not to say that people with sickle cell disease cannot live past 60. Indeed, people with sickle cell disease can live into their 80s. See the “Healthy Living” page for tips on how to live a long, healthy and happy life with SCD.

Sickle cell disease patients are mentally challenged.

False: Most people with sickle cell disease fall within the normal intelligence range. In a study of 60 SCD patients and 60 matched controls (people without SCD), the average IQ of SCD patients was 5.6 points lower than the controls. The average height of SCD patients was also lower than that of the controls, and height was shown to be correlated with IQ. The authors speculated that early factors, like nutrition, could have contributed to both slower growth and mental development in sickle cell patients (Knight et al., 1995). A meta-analysis of sickle cell studies showed that there were small but reliable differences in IQ between SCD patients and healthy controls. The authors of this study suggested that the differences could be due to effects of SCD directly on brain function or due to the effects of having a chronic illness on the brain more generally (Schatz et al., 2002).

There is no cure for sickle cell disease.

False: Bone marrow transplantations have been successful, in some cases, in curing sickle cell disease. The bone marrow donor is usually a sibling with the same bone marrow type as the patient. Unfortunately, only 1 in 10 sickle cell patients is able to find a matching donor. Fortunately, there are other treatments that have been successful in managing SCD (see the “Disease Complications and Treatments” page), and there are many lifestyle changes patients can make to improve their quality of life with the disease (see the “Healthy Living” page).

References