Sickle cell disease is the most common monogenic blood disorder worldwide. It is associated with progressive organ damage coupled with episodes of acute illness. These episodes results from the sticky and stiff red blood cells which clog tiny blood vessels. This often results into various conditions not limited to organ and tissue damage, anemia, increased risk of infection and painful episodes.
Worldwide sickle cell disease contributes a significant burden that is not amply addressed. It’s estimated that 312000 children will be born worldwide with sickle cell disease annually, with the greatest burden existing in sub-Saharan Africa, where 75% of the world sickle cell disease occurs. In Uganda, estimates suggest that 15000 to 20000 babies are born each year with sickle cell disease.
The first survey on sickle cell disease done in Uganda in 1949, reported the district of Bundibugyo in western Uganda to have the highest sickle cell trait prevalence, 45%. This was believed to be the highest in whole world by then.
A cross sectional survey which was carried out in the districts of Mbale and Sironko in the eastern, Mbarara/ Ntungamo and Bundibugyo in western Uganda, showedthe established prevalence of the sickle cell trait in eastern Uganda was 17.5% compared to 13.4% and 3% in Bundibugyo and Mbarara/Ntungamo respectively.
A shift in the prevalence of the disease in Uganda is notable and may be explained by several biological and social factors like intermarriages. Sickle cell disease is an inherited blood disorder. It is marked by flowed hemoglobin, that’s the protein in the red blood cells that carries oxygen to the tissues of the body. So, sickle cell disease interferes with the delivery of oxygen to the tissues.
Red blood cells with normal hemoglobin are smooth, disk shaped, and flexible, like doughnuts without holes. They can move through the blood vessels easily. Cells with sickle cell hemoglobin are stiff and sticky.
When they lose their oxygen, they form into the shape of a sickle or crescent like the letter C. These cells stick together and cannot easily move through the blood vessels. This can block blood vessels and the movement of healthy normal oxygen carrying blood.
The blockage can cause pain. Normal red blood cells can live up to 120 days but sickle cells only live for about 10 to 20 days. Also sickle cells may be destroyed by the spleen because of their shape and stiffness. The spleen helps filter the blood of infections. Sickle cells get stuck in this filter and die. With less healthy red blood cells circulating in the body, you can become chronically anemic. Sickle cells also put you at risk for infections.
There are several types of sickle cell disease a person can have depending on the genes they inherit from their parents. People with sickle cell disease inherit genes that contain instructions or codes for abnormal hemoglobin. HBSS, people who have this form of sickle cell disease inherit two genes, one from each parent that code for hemoglobin “S” which is an abnormal form that causes the red cells to become rigid and sickle shaped.
This is commonly called sickle cell anemia and is usually the most severe form of the disease. HBSD, HBSE and HBSO are rare forms of the disease though under stress, high altitude and severe infections can turn into a menace. For HBAS, an individual inherits a hemoglobin “S” gene from one parent and a normal gene from the other parent. This is referred to as sickle cell trait. These individuals don’t have any of the signs of the disease, hower in extreme cases they can manifest some symptoms.
In Africa, Uganda has the 5th highest burden, situation aggravated by limited and inaccessible formal social support structures to aid patients and families cope better with the psychosocial burden of sickle cell disease. In addition, this has been coupled with stigmatization and discrimination of people living with sickle cell disease causing isolation from family and society. This calls for public awareness campaigns and social mobilization plus the continuous healthy education for professionals.
If an individual has sickle cell disease, it is present at birth, but most infants don’t have any problem from the disease until they are about 5 or 6 months of age. Pledging the government to enforce compulsory new born screening for sickle cell disease. When a child has the disease, parents are notified before the child has started getting the symptoms.
Some children with sickle cell disease will start having problems early on and some later. Early symptoms may include painful swelling of the hands and feet known as dactylitis, fatigue or fussiness from anemia and yellowish color of the skin known as jaundice and icteris that occur when a large number of red blood cells hemolyze .Signs and symptoms vary over time. Most of these are related to the complications of the disease.
With poor or no attention to the sickle cell disease victims, major complications may occur to threaten life with crises including pain episodes. These occur without warning when sickle cells block blood flow and oxygen delivery. People describe this pain as sharp, intense, stabbing or throbbing.
Severe crises can be even more uncomfortable than post surgical pain or childbirth. Pain can strike almost anywhere in the body and in more than one spot at a time, though often occurs in the back, upper and lower extremities and the main trigger being illness, stress, dehydration and changes in the altitude.
Victims to this disorder usually have mild to severe anemia at times which precipitates frequent hospital visits with urgent transfusions required to sustain life. This form of anemia in infants may be brought about by splenic sequestration were a spleen that is located in the upper left abdominal quadrant get blocked by red blood cells which get clogged, making it enlarged quickly.
Since the blood cells are trapped, there fewer cells to circulate in the blood that later precipitate into severe anemia. Due to infection by parvo virus B19,aplastic crisis can be caused ,were the bone marrow stop producing new red blood cells for a while leading to severe anemia.
Although sickle cell disease is a major public health concern in Uganda, the interventions that are currently in place to alleviate it are not sufficient to address the current burden. Furthermore, systematic screening for sickle cell disease using a simple blood test is seldom done and diagnosis is often made when a child presents with severe complications, therefore the government may need to enforce mandatory newborn screening before discharge from maternity wards.
This being a major genetic disease in most countries in sub–Saharan Africa with prevalence ranging between 1% and 2% in north Africa to less than 1% in southern Africa while countries such as Cameroon, Nigeria and Uganda with prevalence between 20% and 30%and in some parts of Uganda as high as 45%, WHO do provide support to MoH to supervise and coordinate interventions relating to the prevention and management of sickle cell disease.
This fosters the genetic counseling services for early detection, efforts to reduce morbidity, chemoprophylaxis, vaccines, clinical care of children and pregnant women and also capacity building as this still on the line of inequities affecting sickle cell disease management.
This year, “celebrating progress” was the theme for world sickle cell day that is always celebrated on 19th of June that was dominated by meditating on the achievements attained in the advancement of knowledge in sickle cell disease management.
This article is written (By Dr. Matovu Richard) in partnership with Specialist Doctors International (SDI)