Shwachman Diamond Syndrome (SDS) is a rare genetic disorder that causes problems with the skeleton, digestion, and with the blood / immune system.  Research studies have estimated that it occurs in between 1 in 75,000 and 1 in 350,000 births. After cystic fibrosis (CF), SDS is the second most common cause of exocrine pancreatic insufficiency in children, and it mustalways be considered when patients present withCF-like symptoms.

Patients with SDS will have problems growing and are usually smaller than their peers.  Doctors can describe this as “Failure To Thrive” when assessing a child’s development. At birth, infants with SDS are on lower growth centiles. Theirheight-for-weight, however, is normal.

Some patients with SDS have skeletal changes. These changes can beseen on a plain x ray but may not be apparent until after thefirst year of life.Shorter ribs can cause breathing difficulties in newborns and changes in the long bones contribute to smaller stature of SDS individuals. They do not produce the enzymes that are needed for the body to break down and absorb food properly.  This can result in stools that are yellow or lighter in colour, fattier or oily, bulky, and foul smelling.  It is readily treated by taking replacement enzymes with food, and in a proportion of cases, the body becomes sufficient in producing its own enzymes in later childhood.

There are significant oral health issues that are often not addressed or appropriately managed, mainly due to lack of awareness. Mucositis and periodontal infections are frequently seen in individuals who are profoundly and persistently neutropenic. However, there is an increased incidence of tooth enamel defects (dental dysplasia) in children with SDS. Dental caries and tooth surface loss are seen in about a third of patients.

As the bone marrow does not produce new blood cells as it should, children may have low levels of the various types of blood cell circulating in their body. If they have too few white blood cells, which fight off infection, they will be more at risk of catching an infection and it lasting longer or being more serious than in other children. This is called neutropenia.

If red blood cell production is affected, they may develop anaemia, causing tiredness and lack of energy. If platelet production is reduced, they may bruise or bleed more easily than usual as platelets are responsible for blood clotting. Low platelet levels are referred to as thrombocytopenia. Occasionally, production of all three types of blood cell is affected (pancytopenia).

Children with SDS also seem to be at a higher risk than other children of developing certain cancers of the blood and bone marrow, although this risk is still small. In a minority of cases, patients may go on to develop blood cancers such as myelodysplastic syndrome and leukaemia.

It is becoming increasingly apparent that many children with SDS suffer from neurological, learning, and/or behavioural difficulties. Recent preliminary studies suggest that a significant number of children experience cognitive and attention difficulties as well as problems with emotional

Management of children with SDS should be multidisciplinary. The child should be primarily under the care of a local general paediatrician, with long term, regular follow up by a paediatric gastroenterologist and haematologist. The multidisciplinary team (MDT) should also include a
dentist, dietician, and psychologist

The charity has a database to keep in touch with the UK SDS families and patients.  Please register here to join this list.

Further information is available on the “Information for Medical professionals” page.  The SDS Canada website has much more detail on the SDS disorder.