Sickle-cell disease (SCD) is a type of genetic blood disorder or disease inherited from a person’s parents. The most common type is known as sickle-cell anaemia (SCA). The condition occurs as a result of an abnormality in the haemoglobin (the oxygen-carrying protein) found in red blood cells. It is a disorder, where the body produces abnormally shaped red blood cells, shaped like a half moon or crescent. (Imagine or picture a half doughnut or banana). Because of their abnormal shape, the cells can often get stuck in the blood vessels and block the normal blood flow or passage. The cells also do not carry enough oxygen for the body and do not last as long as normal (round shaped) red blood cells.
Common symptoms of the disease include painful episodes, such as “sickle-cell crisis” (attacks of pain); anaemia (a condition where red blood cells cannot carry enough oxygen around the body), which can cause tiredness and shortness of breath; swelling in the hands, feet and joints; increased risk of serious infections (mainly bacterial infections); and stroke. Long term pain may also develop as people get older.
Sickle-cell disease occurs when a person inherits two abnormal copies of the haemoglobin gene, one from each parent. Problems often begin from around the ages of 3 to 6 months and the average life expectancy of sufferers is between 40 and 60 years in the developed world. Life expectancy is considerably lower in less developed countries, especially in countries lacking good health infrastructure. The condition affects mainly black people, especially of African and Caribbean origin, where the disease is prevalent.
A sickle cell attack (or crisis) can be triggered by temperature changes, stress, dehydration and high altitude. The disease is diagnosed by a blood test. Some countries, like the UK, routinely test all babies at birth for the disease. Diagnosis is also possible during pregnancy.
The care and management of people with sickle-cell disease may include infection prevention with vaccination and antibiotics, high fluid intake, folic acid supplementation and pain medication. Treatment may include blood transfusion and the medication hydroxycarbamide (hydroxyurea).
A relatively small proportion of people have been cured through the advancement of science and medical intervention by the process of transplant of bone marrow cells (or stem cell transplant). This area of medical science is relatively new and, as can be imagined, costs a colossal sum. Although, this is still at its early trial stages, it is a very expensive option for many, especially those living in Africa.
About 4.4 million people, as of 2015, were said to have the sickle-cell disease. An additional 43 million people have the sickle-cell trait. (A person with a single abnormal copy does not usually have symptoms of sickle cell anaemia, but is said to have sickle-cell trait (commonly referred to as a carrier)). About 80% of sickle-cell disease cases are believed to occur in sub-Saharan Africa. It also occurs among people of African origin living in other parts of the world, including the UK, where there is a high number of cases. Sub-Saharan countries like Nigeria, Kenya, Democratic Republic of Congo, Uganda and some other countries that have a high exposure to Mosquito or malaria, have high cases of sufferers.
In 2015 sickle cell disease resulted in about 114,800 deaths.