Waardenburg Syndrome: Causes, Symptoms And Treatment
There are a large number of different disorders and conditions that can damage and harm our health. Many of them are highly known by the majority of the population, especially when they are relatively prevalent or dangerous. The flu, cancer, AIDS, diabetes or Alzheimer’s are just some examples of this. Occasionally, some that are not taken into account by the majority of the population also come to the fore in the face of epidemics or awareness campaigns, such as Ebola, chronic obstructive pulmonary disease (COPD) or amyotrophic lateral sclerosis (ALS).
But there are many diseases that we have practically never heard of, such as those considered rare or a large number of genetic disorders. One of them is Waardenburg syndrome, which we will talk about along these lines
Waardenburg syndrome is a strange disease of genetic origin which is estimated to be suffered by one in every forty thousand people and which is classified as one of neurocristopathy, disorders generated as a consequence of alterations in the development of the neural crest.
This disease is characterized by the presence of alterations in facial morphology, highlighting the presence of dystopia cantorum or displacement of the side of the inner canthus of the eye, pigmentation problems both at the level of the skin and eyes that cause them to have a light color (it is not uncommon for eyes to be present with a characteristic intense blue or that heterochromia appears, and that part of the hair is white) and a certain level of hearing loss or even congenital deafness. It is not uncommon for vision problems to appear either, although it is not one of the critical symptoms for diagnosis.
Additionally, they may appear other disorders linked to the digestive system, movement or even intellectual capacity The hair may also appear gray or even with white streaks, as well as light spots on the skin. Despite this, this syndrome is characterized by being highly heterogeneous, having different types of symptomatological presentation.
Waardenburg syndrome, as we have said, does not have a single way of presenting, but different subtypes of this syndrome can be distinguished. Among them, the most notable are four, the first two being the most common (within rare diseases) and the second two being the least common.
Waardenburg syndrome type 1
Waardenburg syndrome type 1 is one of the most common. In this type of presentation of the syndrome, all of the previously mentioned symptoms occur: morphofacial alterations and pigmentation problems along with possible congenital deafness (although it only occurs in around 1 in 4 cases).
The presence of one eye of each color or heterochromia is very frequently observed, the light tone of the eyes (generally with a tendency towards blue) and skin and, one of the characteristic symptoms of this type, the presence of dystopia cantorum or displacement of the inner canthus of the eye. This type of symptom is reminiscent of hypertelorism, with the difference that in reality the distance between the eyes is not greater than the average (although in some cases hypertelorism may also appear).
Waardenburg syndrome type 2
Types 1 and 2 of Waardenburg syndrome share almost all of the diagnostic criteria, with the symptoms being practically identical. The main difference is the fact that in type 2 dystopia cantorum does not occur (if we did so we would be facing Waardenburg syndrome type 1).
In addition, in this presentation of the syndrome the facial morphological alterations tend to be somewhat less marked than in comparison to type 1, while the deafness presented is usually somewhat more evident and frequent, being the majority (appears in 70% of cases). . Spina bifida or lack of genital development may also occur.
Klein-Waardenburg syndrome or type 3
This type of disorder is characterized because in addition to the previous symptoms (it is generally closer to type 1), there are usually malformations in the upper extremities and neurological alterations. Likewise, it is usually more correlated with movement problems, muscle tension, cerebrospinal disorders or functional diversity at an intellectual level Drooping of the eyelid in at least one of the eyes is also common, a symptom called ptosis, despite the absence of dystopia cantorum.
Very similar in symptoms to Waardenburg syndrome type 2, but also adding alterations in the enteric and gastrointestinal system which cause a smaller number of neurons managing the intestines and which usually correlates with constipation and other digestive problems such as Hirschsprung’s disease or congenital megacolon, in which feces are not expelled normally due to problems with the neuronal ganglia of the enteric system and An enlargement of the intestine and colon occurs as a result of their obstruction.
Causes of this alteration
Waardenburg syndrome is a disease of genetic origin, which can be inherited or appear due to a de novo mutation The heritability of this disorder depends on the type we are analyzing.
Types 1 and 2 are transmitted in an autosomal dominant pattern. The problems seem to arise from altered neuronal migration during development, which generates the symptoms and a lack of melanocytes (causing pigmentation alterations).
One of the genes that is most associated with the disorder in its most common typologies in types 1 and 3 is PAX3 (it is considered that 90% of type 1 have mutations in this gene). But he’s not the only one. Type 2 is more associated with the MITF gene, and type 4 with an association of genes including EDN3, EDNRB and SOX10.
Treatment
Waardenburg syndrome is a genetic disorder, which does not have, at least at this time, any type of curative treatment. However, many of the difficulties that the syndrome generates are treatable, carrying out an approach more focused on specific symptoms and complications depending on the dysfunction or risk that it may pose for the patient.
The most common type of intervention is the one that has to do with possible deafness or hearing loss, in which techniques such as cochlear implant could be used Surveillance and prevention of the appearance of tumors (for example melanomas) is also something to take into account and if they appear they must also be appropriately treated. Some skin and facial morphology alterations could also require surgery, although it is not as common. Finally, if eye problems appear, they must also be treated.
For the most part, Waardenburg syndrome does not generate nor does it usually present major complications in its most common modalities, type 1 and type 2, so that those who suffer from it can usually lead a typical life. This does not mean that they do not have difficulties, but in general the prognosis is positive in terms of having a good quality of life.
In the case of subtypes 3 and 4, the number of complications may be higher. In the case of 4, the condition of megacolon It can lead to alterations that endanger the life of those who suffer from it The latter is the case of megacolon, if it is not correctly treated.
Treatment of these complications may require surgery to correct the megacolon or improve the functionality of the upper extremities (for example, reconstructing the extremities and separating the fingers). In the case of intellectual disability, the application of educational guidelines may also be necessary that take into account the possible problems derived from it, such as an individualized plan in the educational field (although in general the intellectual disability is usually mild).
Likewise, the possible psychological impact must also be assessed: the presence of morphological anomalies can trigger anxiety, self-esteem and depression problems derived from self-image. If necessary, psychological therapy can be of great help.
