What's Shwachman's syndrome?
It is a pathological condition, described for the first time by Dr Shwachman and by Dr Diamond from Boston in 1964, caracterized mainly by ipoplasia of the exocrine pancreas , low height, disorder of medulla ossium and various alterations to the bones.
What does it mean?
the ipoplasia of the exocrine pancreas indicates a congenital defect about the development of that part of the pancreas that produces the enzymes to digest food. It follows a pancreatic insufficiency and thus an important defect in digestion and food absorption. This defect is inclined to weaken with the years.
Low height is present since birth and it is not corrected by any therapy, eventhough the growth has a regular speed.
Dysfunctions of medulla ossium are manifold. As a whole there is a scarce development of the medulla, replaced partly by fatty tissue, with consequent scarce production of red corpuscles , blood platelets and the white corpuscles called "granulociti neutrofili", assigned to the defences of front line against the bacteria. The most frequent defect concerns the neutrofili: we talk about neutropenia, that is usually intermittent or cyclic (in other words goes and comes back). Moreover the neutrofili are generally little moving and thus occur with difficulty where there is infection. The scarcity and hypomobility of neutrofili encourage infections, aboove all in a little child: otitis, bronchial pneumonia, osteomyelitis, infections to the cutis, septicaemia.
Piastrinopenia (defect of blood platelet) and anaemia (defect of red corpuscles) are less frequent. In a little child there is a high value of haemoglobin of fetal type and in certain case there is also a tendency of mieloproliferativa, that is the medulla tendency to degenerate in leucaemia.
Bones alterations are of different type: above all they are structure alterations in the part near to the big articulations ( metafisaria dysplasia) near knees and hips ) or at the ribs level (with contracted chest). There can be a valgoid condition (deflected knees ). These alterations are perhaps partially responsible of the height defect, even if they weaken with years.
Are other associated anomalies known?
In single cases other alterations have been noticed: some modest psychomotor delay (quite frequent, but without substantial mental problem), diabetus mellitus, renal disfunction, ittiosi (squamous cutis), liver disfunction, anomalies to the teeth, megacolon, defect of immunoglobuline.
Which is the syndrome cause?
The syndrome is transmitted on a genetic hereditary base: from two parents who are healthy bearers of an altered gene, 25 % of affected sons is born (we talk about "recessive autosomic transmission").
However the defect that joins the different alterations of the syndrome is still unknown neither is the gene knownnoto changed the cause.
How much is it frequent?
It is considered a relatively rare condition, even if we have no certain frequency data today: there are only rough estimates, from a suffering on 10.000 people born to a suffering on 200.000 people born. The problem is that the diagnosis can be often very difficult and many cases are problably completely ignored.
How is it possible to diagnose it?
The syndrome is suspected in all children who have a low weight and lenght to their birth and that they are not preemie; in all children who have a retarded height growth; in all children who have intestinal disorder with the emission of huge faeces and with grease. But it is suspected also in all children with neutropenia more or less associated to an anaemia and low number of blood platelet. The syndrome is suspected also in a young or adult person with low height with neutropenia that diversely could not be explained:in more advanced age disturbs from pancreatic insufficiency can be also lacking.
Some tests testing the pancreatic function, beside the blood tests to count the white corpuscles, red corpuscles and blood platelets, and radilogic tests on bones, enable to formulate correctly the diagnosys in presence of a negative sweat test. The sweat test is necessary to differentiate this syndrome from the cystic fibrosis, an illness that the Shwachman's syndrom can be similar.
How is it posssible to have treatment?
At the moment we have only symptomatic cares. The pancreatic insuffiency is treated with a pancreatic extract with a moderate dosage. In certain cases it can be necessary to add A vitamine, D vitamine and E vitamine. Infections must be opportunely and energetically treated. All possible vaccinations must be precociously carried out. The most serious conditions of neutropenia are today treated, still in an experimental way, with specific factors which stimulate the growth and the the medullary cells maturing. The leukaemic degenerations are treated also with the transplant of bone medulla. b/p>
Which is today the suffering people's destiny?
There are certainly some risks, also for life, connected to the infections in the first age of life. The digestive disturbs tend to correct partly with age and however are well controlled with the pancreatic extract. A good part of the patients can reach the adult age in quite good health conditions. The most crucila problem remains that of malignant medulla transformation, for which today we have advanced pharmacological and transplantic resources. The psychomotor delay of some patients can require a particular support for the learning development.
Open problems given to the research
In this sector the research has moved till now few and hars steps.
Unsolved problems are many. In particular :
There are no accurate epidemiological knowledge; we do not know how often is the syndrom and we do not have a complete census about its possible symptoms.
We do not know the gene in cause and we do not know the defect which is the base of clinical manifestetions apparently so inhomogeneous and distant between them.
We need to have knowledge as for more efficacious treatments and surer of neutropenia and for the possible prevention of leukaemic transformations.
We are asking also if there are pharmacholical possibilitis to intervene precociously on skeletal alterations.