What is Shwachman–Diamond Syndrome?
Shwachman-Diamond Syndrome is an extremely rare inherited pathological condition of the autosomal recessive type in which the bone marrow of the child does not function the way it should resulting in reduced blood and platelet counts causing a variety of symptoms like poor growth and failure to thrive as the food does not get absorbed properly. There may also be skeletal abnormalities as a result of this condition.
In Shwachman-Diamond Syndrome since the bone marrow does not function adequately, hence due to reduced blood counts they become more prone to frequent infections like pneumonia, ear infections, and other skin infections. The child may also have anemia due to low production of red blood cells causing extreme fatigue, lethargy and weakness, easy bleeding and bruising.
As the child grows, due to Shwachman-Diamond Syndrome the child may be at an increased risk for developing serious complications due to a malfunctioning bone marrow like myelodysplastic syndrome and aplastic anemia. Shwachman-Diamond Syndrome has also been shown to affect the pancreas and because of this the digestion of the patient gets affected and the nutrients required by the body for a healthy growth is not given to the body resulting in poor nutritional status of the patient. Such patients are thin and find it very difficult to gain weight and may also look malnourished but this condition gradually improves with time and age.
Shwachman-Diamond Syndrome also results in many skeletal abnormalities. The patient may have difficulty with bone formation and bone growth of usually the hips and knees. Some children may be born with short ribs which may affect normal breathing in a big way. Hence patients with Shwachman-Diamond Syndrome are generally short statured.
What are the Causes of Shwachman–Diamond Syndrome?
As stated above, Shwachman-Diamond Syndrome is an autosomal recessive inherited disorder which is caused by mutations in the SBDS gene. Since it is autosomal recessive trait hence a copy of the defective gene is taken from both parents for the child to get Shwachman-Diamond Syndrome. Genetic testing can clearly identify whether a child is at risk for developing Shwachman-Diamond Syndrome or already has it.
What are the Symptoms of Shwachman–Diamond Syndrome?
As stated, Shwachman-Diamond Syndrome affects many organ systems of the body including the pancreas, skeletal system and bone marrow and hence the symptoms differ from patient to patient. Some of the most common symptoms of Shwachman-Diamond Syndrome are:
- Chronic foul smelling diarrhea which is more often than not greasy in texture
- Frequent infections due to low blood cell counts
- Poor growth
- Pale skin
- Always being tired and fatigued
- Severe weakness with inability to complete basic tasks
- Easy bruising and bleeding
- In some cases rashes on the face and body
- Ribcage abnormalities
- Short stature
- Delayed tooth development
- Gum abnormalities.
How is Shwachman–Diamond Syndrome Diagnosed?
If a patient has risk factors for developing Shwachman-Diamond Syndrome then frequent visit to physicians are required. To confirm the diagnosis of Shwachman-Diamond Syndrome the physician will conduct the following tests:
- Complete blood count to see if the count is low or not
- Check the function of the kidneys, liver, and pancreas
- Pancreatic Stimulation Testing. This is done to test the ability of the pancreas to respond to secretin which is a hormone which facilitates absorption of food
- Evaluate the status of the bones
- Bone marrow biopsy
- Genetic testing to see if there is mutation in the SBDS gene which can confirmatively give a diagnosis of Shwachman-Diamond Syndrome.
What is the Treatment for Shwachman–Diamond Syndrome?
Treating Shwachman-Diamond Syndrome requires a multidisciplinary team effort as multiple body systems are affected by this condition. Hence, patients with Shwachman-Diamond Syndrome need to be in close touch and seek care from many specialists including hematologist, gastroenterologist, endocrinologist and of course orthopedist.
Some of the treatments for Shwachman-Diamond Syndrome are:
- Replacement of the pancreatic enzyme helps in breaking down the food into more smaller parts and makes digestion of food easier so that the body gets more nutrients required by it to function normally.
- Intravenous Antibiotics is given to fight off any indwelling infections which the patient will be prone to because of the low counts due to Shwachman-Diamond Syndrome.
- Bone marrow stimulation can be done to stimulate the bone marrow so that it produces more cells and hence bring the blood count to as normal as possible. Some of the medications given for stimulating the bone marrow are Procrit, neupogen, and Leukine.
- In cases of skeletal abnormalities due to Shwachman-Diamond Syndrome, surgery may need to be done to correct the deformities. Even post surgery, the patient will need to be under close observation of the orthopedist for any complications.
- Blood transfusion is done for patients who develop anemia as a result of Shwachman-Diamond Syndrome.
- Routine dental care is also required for patients with Shwachman-Diamond Syndrome as they tend to have frequent gum diseases and tooth abscesses.
What is the Prognosis for Shwachman–Diamond Syndrome?
With the advancement of medical science over the years, the overall prognosis for Shwachman-Diamond Syndrome has improved and in fact most patients lead a normal life despite having this condition albeit they need frequent observation by physicians but these follow ups are normally done on an annual basis just to check if anything untoward has turned up due to Shwachman-Diamond Syndrome. The percentage of a child developing leukemia is about 15-20% a later stage in life due to Shwachman-Diamond Syndrome. Vitamin A, E, and K deficiencies are also common inpatients with Shwachman-Diamond Syndrome.
- Boocock GR, Morrison JA, Popovic M, et al. Mutations in SBDS are associated with Shwachman-Diamond syndrome. Nat Genet. 2003;33(1):97-101. doi: 10.1038/ng1062. (https://www.ncbi.nlm.nih.gov/pubmed/12496757)
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