What is Hereditary Spherocytosis (HS)?
Hereditary Spherocytosis or HS is a red blood cell disorder where the cells take on a shape of a ball (or sphere) instead of the normal shape of a red cell (which looks like a ‘doughnut)’. Because the red cells are in the shape of a ball they are more fragile than normal red cells. The fragile red cells can break down which is also known as red cell haemolysis and cause anaemia.
What causes Hereditary Spherocytosis?
Hereditary Spherocytosis is caused by an abnormal protein on the surface of the red cells. It is a genetic disorder so there is usually a family history of HS; HS is usually passed on from one parent to their children.
How common is Hereditary Spherocytosis?
HS is relatively common – around 1 person in every 5000 people has HS (around 800 people in Melbourne; population 4 million).
What does having HS mean?
There are three main common problems associated with having HS:
There is another uncommon potential problem for people who have Hereditary Spherocytosis associated with a viral infection called “Slapped cheek”. Slapped cheek is caused by a virus called Parvovirus which can infect bone marrow cells and put the red cell producing cells “to sleep”. Because patients with HS need the bone marrow to be rapidly replacing the fragile red cells, this infection can cause a severe anaemia; patients can become very pale and sometimes even require blood transfusions. Fortunately this problem is uncommon.
How is Hereditary Spherocytosis diagnosed?
HS is now diagnosed with a simple blood test. It is also important for a doctor to examine patients with HS to see if they are jaundiced or have an increase in the size of the spleen.
What do I need to do now that I (or my child) has been diagnosed with Hereditary Spherocytosis?
Most patients with HS do not need to do much about their condition at all. The bone marrow has the capacity to increase the number of red cells it produces many fold and is able to keep up replacing the fragile cells.
A few things may be helpful:
Will I (or my child) need a splenectomy?
Removing the spleen (splenectomy) has been used a lot in the past in the treatment and management of patients with HS; it stops the red cells from breaking down and solves the problems of HS.
Removing the spleen has problems however – the spleen is an important organ in the immune system and patients who do not have a spleen may be prone to getting serious infections. This risk is higher in younger children but may be less than previously expected because of newer vaccinations. It is now generally recommended to avoid splenectomy in children younger than 6 years and to ensure that children who may need a splenectomy have all the appropriate vaccinations.
Another approach for some of these young patients is to remove only a small part of the spleen – partial splenectomy. This is done in a few hospitals and there is some experience to say this may be very helpful for some patients.
Resources used to produce this information sheet.
- Bolton Maggs, PHB Stevens, RF Dodd, NJ Lamont, G Tittensor, P and King, M-J on behalf of the Haematology Task Force of the BCSH. “Guidelines for the diagnosis and management of hereditary spherocytosis”. BJH 2004 126 pp 455 – 474
Dr Chris Barnes is a Paediatric Haematologist practicing at Melbourne Paediatric Specialists.