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Sickle Cell Anemia
Diagnosis
Sickle cell anemia is now the most common genetic condition in England , affecting 1 in 200 live births. As part of an NHS initiative, universal neonatal screening started in 2005. Since then all new born babies have a blood spot test on day 5 in order to diagnose sickle cell anemia at an early age to reduce mortality and morbidity. This will continue to improve the life expectancy of these patients in the UK .
Sickle cell anemia is caused by an abnormality of a gene. It affects red blood cells which have a protein called hemoglobin and carry oxygen from the lungs to all parts of the body. It is an inherited blood disorder and both parents have to pass on the abnormal gene for there to be a chance of a child having the disease.
If you inherit the problem gene from one parent and a normal gene from the other, a child will have a condition called ‘sickle cell trait' or be a carrier, which doesn't usually cause any symptoms, but can be passed on to the next generation.
Both sickle cell and sickle cell trait are more common in some racial groups than others. They affect people from the Mediterranean , Africa , the Caribbean , Middle East , Turkey , the Arabian Peninsula and the Indian subcontinent. Therefore, it is worth having a blood test if you are from one of the aforementioned ethnic backgrounds, even if you have no symptoms, in order to find out whether you are a carrier of the gene or not so that you can make an informed decision about the future.
Fig 1 |
Fig 1 illustrates how the disease is inherited. Therefore, for every pregnancy when both parents have sickle trait, there is a 1in 4 chance that their offspring will have sickle cell anemia.
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What causes the signs and symptoms?
Fig 2 |
In normal people the blood cells are donut-shaped and flexible, but in people with sickle cell the cells are hard and sickle shaped as in fig 2. Because of their shape, the sickled cells can block small blood vessels, and stop oxygen from going where it's needed in the body. This blockage can cause a person pain, which is described as the sickle cell crisis and is the commonest complication.
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Fig 3 |
Pain usually occurs in the long bones in older children but in younger children it can present with painful, swollen hands and feet as shown in fig 4.
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Fig 4 |
These abnormal red cells do not last in the circulation and breakdown causing anemia, which is low hemoglobin. Patients are usually tired and pale. Some may also have other complication like stroke or jaundice due to the excessive break down of the red cells producing bilirubin that the liver struggles to get rid of. They also have the tendency to develop gallstones causing tummy pain. Other complications include priapism (recurrent painful erection), kidney problems, hip and joint pain and bed-wetting. It is difficult to predict these complications, but we know that patients with sickle cell anemia usually have mild disease. |
Treatment
Treatment may require hospital admission depending on the severity of the pain but we encourage the disease to be managed at home with strong painkillers. Hospitalization may be required with more severe pain or other complications.
Occasionally the anemia may be so severe that it requires a blood transfusion in hospital. This may be due to a pavovirus infection, splenic or liver sequestration crisis. (Blood accumulating in these organs causing pain)
Patients that have had a stroke have an increased risk of having a further stroke and therefore it is recommended that they have recurrent blood transfusions.
Hydroxyurea is a drug which has been used for patients that have had severe sickle cell anemia but this has to be done with close monitoring of the blood counts and follow-up.
Sickle cell anemic patients require additional immunizations to prevent them from getting particular infections as well as regular preventive antibiotics, which need to be taken on a daily basis.
Follow-up
Patients are followed up regularly from birth. The standards and guidelines for the clinical care of sickle cell disease in childhood aims for all patients diagnosed to be started on prophylactic antibiotics from 8 weeks of age and for them to have received all of the primary immunizations. Parents are educated on the management of the condition and pain. They are also provided with easy access to the hospital when necessary and community care. Children with sickle cell anemia require regular follow up to monitor their health, growth, nutrition and any of the complications mentioned above including proper transition to adult services. It is very important to note that generally patients with sickle cell anemia can live a normal life particularly if they take care of their health by doing all of the above. More research is required to predict severity of the disease earlier on in life to try and prevent some of the complications.
The Future
Bone marrow transplantation (“BMT”)
This is the only treatment that is potentially curative but as there is a large variation in the severity of patients with sickle cell disease and in view of the high risk of morbidity and mortality from the bone marrow procedures, BMT is not appropriate for all patients.
 Dr Olufunke Wilkey graduated from Obafemi Awolowo University . Sickle cell anemia is one of her special interests having treated many patients with the disease in Nigeria and currently where she works now. She became a consultant pediatrician in 2002 having trained at several hospitals including Great Ormond Street hospital. She is currently working as a general pediatrician with an interest in Hematology and Oncology at the North Middlesex hospital department of Pediatrics that is in partnership with Great Ormond Street . She sees private patients at Holly House, Kings Oak and the Nuffield Hospitals .
For more information about sickle cell visit the sickle cell society http://www.sicklecellsociety.org/ or to read more about the personal experiences of patients with sickle cell disease please visit http://www.childrenfirst.nhs.uk/teens/gosh_tv/lloyd/index.html
http://news.bbc.co.uk/cbbcnews/hi/newsid_6140000/newsid_6146400/6146468.stm
You may also contact Dr. Wilkey:
Olu Wilkey
Consultant Paediatrician
North Middlesex Hospital in partnership with
Great Ormond Street Children's NHS Trust
Sterling Way
London
N18 1QX
Telephone No 0208 887 2945
Fax No 0208 887 2932
Email OluWilkey@aol.com
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