Sickle Cell Disease

The oxygen in the air that humans breathe needs to be carried all over the body. This function is performed by the red blood cells which carry the oxygen to all parts of the body.

The hemoglobin in the red blood cells carry the oxygen. Normally red blood cells have hemoglobin A and are in a round shape and are soft which make it possible for the red blood cells to squeeze through tiny blood vessels. Normally red blood cells have a life span of approximately 120 days after which they are replaced by fresh cells.

Those with sickle condition have red blood cells containing an abnormal type of hemoglobin called Hemoglobin S. The red blood cells become crescent (sickle) shaped and hard making it difficult for the cells to pass through small blood vessels. Moreover the red blood cells in this condition have a life span of only 16 days. When sickle-shaped cells plug up small blood vessels, lesser blood reaches various parts of the body. This damages the tissue that does not receive normal blood flow. This is what causes the complications of sickle cell disease.

Sickle cell disease is common in persons of African ancestry. It also affects persons of South and Central America, the Caribbean, the Mediterranean, Arabia, and East India.

Sickle Cell Trait is a condition where both Hemoglobin A and Hemoglobin S are produced. Thus the person with Sickle Cell Trait are generally healthy. Sickle Cell Tait can be determined by a blood testfollowed by a laboratory technique called Hemoglobin Electrophoresis will determine the type of hemoglobin you have.

There are various kinds of sickle cell disease. The most common are Sickle Cell Anemia, Sickle-Hemoglobin C Disease, Sickle Beta-Plus Thalassemia and Sickle Beta-Zero Thalassemia.

Sickle cell disease is an inherited disorder. The hemoglobin genes are inherited from the parents on two sets… one from each parent. For example if one parent has Sickle cell Anemia and the other is normal, the child will have Sickle Cell Trait. If one parent has Sickle Cell Anemia and the other has Sickle Cell Trait, there is 50% probability that the child will have Sickle Cell Disease. If both parents have Sickle Cell Trait, there is a 25% probability that the child will have Sickle Cell disease.


The lack of oxygen flow to tissues can lead to a number of complications.

Acute Chest Syndrome – This is a serious condition caused by infection of trapped red blood cells in the lungs. This results in fast or difficult breathing, chest pain, and coughing.

Anemia (low red blood cell count) – Patient is easily tired
Aplastic Crisis – This leads to temporary lack of production of red blood cells which result in paleness, low activity, fast breathing and fast heartbeat.
Bone Necrosis – Degradation of bone tissue which can lead to hip replacements and other complications.
Hand and Foot Syndrome – Painful swelling in the hands and feet

Severe Infections – Sepsis (blood stream infection), meningitis, and pneumonia. The risk of infection is increased because the spleen does not function properly.
Splenic Sequestration Crisis – The spleen is the organ that filters blood. Rapid enlargement can result due to entrapment of sickled cells in the spleen. This condition can be fatal.

Stroke – Occurs when sickled cells create a blockage within the brain. Signs include seizure, weakness in the arms and legs, speech problems, and loss of consciousness.


There is no universal cure for sickle cell disease. Research in gene therapy, the ultimate universal cure, is currently underway which hope to offer a permanent and effective cure for this disorder.

Although, there is no cure, management of the disorder can help a patient live with the disorder. Management of patients with sickle cell disease starts with early diagnosis, preferably in the newborn stage and includes vaccinations, penicillin prophylaxis and folic acid supplementation.

Complication management includes administration of oxygen, antibiotics, pain management, intravenous fluids, blood transfusion and surgery. The patients are best managed in a comprehensive multi-disciplinary program of care. Advent of Sickle cell crises may include the administration of oxygen, pain-killing drugs, and oral and intravenous fluids to reduce pain and prevent complications. Anemia can be corrected by blood transfusions which boost the number of normal red blood cells in circulation. In children, regular transfusions also can help prevent recurring strokes, other disabling nervous system complications and enlargement of the spleen before they become life-threatening. Newer drugs and treatment are being utilised like the anticancer drug hydroxyurea. Transplanting cord blood is another emerging treatment.

With proper diagnosis and preventive care the quality the disorder may not necessarily be fatal and the length of life can be managed effectively. In 1970, the estimated median expected survival was 20 years for affected persons living the U.S. With advances in the diagnosis, treatment, and prevention of complications, the life expectancy of persons with sickle cell disease has now improved.


RH factor

Blood Groups have a +ve or -ve appended to them. For example O+ve or O-ve. What does this +ve or -ve signify and whar relevance does it have on our health.

The +ve or -ve refers to the presence or absence of two Rhesus genes called the D or d which are inherited from each parent. A person is Rh(D) -ve if he/she has got a d gene from each parent making them d/d. A person is Rh(D) +ve if he/she has got D gene from each parent making them D/D or a D and d from the parents (either ones) making them D/d or d/D. Thus it is possible to have a Rh(D) -ve child from a father who is Rh(D)+ve and mother who is Rh(D) -ve. If the father has both a D and d gene; the offspring may inherit the d gene and shall be Rh(D)-ve if the mother is also Rh(D) -ve. The child from a D/D father and D/d or d/d mother will always be Rh(D) +ve since it will get a D from the father and either a D or a d from the mother. The d gene is not relavant. What is the presence or absence of the D which will make a person Rh(D) +ve or Rh(D) -ve.

All this is fine. The problem is that the Rh(D) +ve blood contains the D antigen which stimulates the Rh(D) -ve blood into producing antibodies against it.. A Rh(D) +ve woman would never produce an antibody against a Rh(D) -ve child, as +ve blood does not produce anti-d – there is no anti-Rh(d). However the problem comes where the mother is Rh(D) -ve while the child is Rh(D) +ve.

Erythroblastosis faetalis is one form of Rhesus disease. Red blood cells from the baby’s blood stream may enter the blood stream of the mother across the placenta, which cause the mother to make antibodies to the baby’s Rh factor. These antibodies cross the placenta and destroy the baby’s red blood cells. This destruction causes the baby to become anaemic and it can die before birth. If the baby does not die before birth, its bone marrow produces extra red blood cells which are immature and releases these into the baby’s blood steam. The haemoglobin from the broken down red blood cells breaks down into bilirubin, which is released into the mother’s blood stream across the placenta and cleared through her metabolism. But, after the baby is born, the bilirubin builds up in it’s blood stream, causing kernicterus, which is a syndrome characterised by poor feeding, poor body tone, seizures and poor breathing which may result in death. Hydrops faetalis is another form, also resulting from breakdown of red blood cells due to Rh incompatibilites, causing severe anaemia before birth. The baby is born swollen with a large liver, an enlarged heart and fluid on the lungs and in the tummy.

In such cases prevention is to be exercised. A blood test should be done at the start of pregnency to determine the D factor of the mother. If it is a Rh(D) -ve mother, further tests will be performed throughout the pregnancy to ensure that her blood is not producing Rh antibodies against her baby`s blood. If a bleed from the placenta should occur at any time during pregnancy and the foetal blood is Rh(D) positive, this would result in antibodies being produced. This is why it is essential to keep a note of when blood tests are due and what the results are.

Further she should be treated with a dose of anti-Rh antibody at about 28 weeks of pregnancy. This would help to prevent antibodies being produced if an unsuspected placental bleed were to then occur, or had already occurred within the preceding 72 hours of the injection. If this has not been done, then the mother should receive an anti-Rh gamma globulin within 72 hours of delivery. This way, the blood cells are destroyed before the three days are up and her own immune system is not provoked into producing its own anti-Rh(D).

It is highly recommended that an anti-D injection be given after any incident which could result in red Rh(D) positive cells becoming present in the mother`s bloodstream, whether this be medical intervention where Rh(D) blood has been used, a fall which may cause a placental bleed, or a miscarriage.

If the baby is born with either of the above two Rh diseases, then exchange transfusion, where equal amounts of blood are put in and taken out, is performed. Exchange transfusions can also be carried out before birth while the baby is still in the womb, if measurements of bilirubin in the amniotic fluid are becoming dangerously high.