KGB Syndrome, also known as Hermann-Pallister Syndrome, is a very rare hereditary disorder that affects all body systems. The genetic disorder is characterized by unusual facial features, skeletal abnormalities, and delayed development.
What is KGB Syndrome?
Basically, the KGB syndrome is based on a mutation in the gene ANKRD11, which is located on chromosome 16. The protein made from this gene allows other proteins to interact with each other. See AbbreviationFinder for abbreviations related to KGB.
The term KGB syndrome goes back to the first letters of the family names of the first patients with this disease, which were described in 1975 by Jürgen Herrmann, Philip David Pallister and John Marius Opitz in the medical literature. KGB syndrome is one of the rare genetic diseases. So far it has been described to more than 200 people.
For reasons that are still unknown, the disease is prevalent in male patients. Physicians assume that the diagnosis is rarely made due to the mild course forms and that the symptoms are assigned to other diseases. The typical features include the fascial and cost-vertebral dysmorphism. The diagnosis is made clinically.
Basically, the KGB syndrome is based on a mutation in the gene ANKRD11, which is located on chromosome 16. The protein made from this gene allows other proteins to interact with each other. It occurs, among other things, in the neurons in the brain. In addition to the development of the brain, it is also involved in the learning and memory processes.
In addition, however, it can also become active in other cells, where it is involved in normal bone development, among other things. The mutations in the ANKRD11 gene result in an exceptionally short protein that can hardly or not at all fulfill its function. The reduction in the effect of the protein thus underlies the symptoms of KGB syndrome. KGB syndrome is inherited in an autosomal dominant pattern.
Some cases indicate direct inheritance from one parent, most often the mother. In others, however, the mutation appears to have formed spontaneously, affecting even those individuals with no family history of genetic disorders.
Symptoms, Ailments & Signs
One of the characteristic features of KGB syndrome is the exceptionally large upper central incisors (macrodontia). Other facial dysmorphisms include a broad, short skull with a triangular face shape and a high bridge of the nose. The eyes are set wide apart and are covered by bushy eyebrows, which often grow together.
The space between the nose and the thin upper lip is remarkably large. The hairline can also be abnormal. The skeletal anomalies of the patients are due to a slow mineralization of the bones. This is primarily expressed in short stature. Deformation of the spine and ribs can often be observed. In addition, anomalies can occur in the hands, with the little finger in particular being very short or bent.
The mental development of the affected patients is delayed. In most cases, mild to moderate intellectual disabilities are diagnosed. These are often accompanied by emotional disorders such as hyperactivity or anxiety disorders. Hearing loss, strabismus or heart defects are rarely diagnosed in the presence of KGB syndrome. Seizures, on the other hand, are relatively common (about 50% of all cases). They occur in some patients as early as 10 months and usually manifest themselves as lightning-nick seizures.
Diagnosis & course of disease
The diagnosis of KGB syndrome is made after a thorough clinical evaluation, a detailed patient and family history, and identification of the characteristic physical findings. This is usually done clinically. Genetic testing for KGB syndrome has also been available for a number of years.
The definitive diagnosis is not made until the age of seven to eight years, when the teeth have finally formed and the macrodontia can be clearly seen. In order to be absolutely certain, a gene panel analysis or a sequencing technique can be used to localize the genetic malformation.
KGB syndrome is not a life-threatening condition. The favorable prognosis can be additionally supported by close-meshed and interdisciplinary medical care.
A number of different symptoms and complaints can be felt by the patient with KGB syndrome. First and foremost, most patients suffer from relatively unusual facial features and also skeletal abnormalities. This can lead to bullying and teasing, especially in childhood, which often leads to psychological problems and depression.
Those affected also suffer from severely delayed mental development, resulting in retardation and underdevelopment in most cases. It is not uncommon for those affected to depend on the help of other people in everyday life and can no longer carry out various everyday things independently.
The quality of life is significantly reduced by the KGB syndrome. Furthermore, most patients suffer from short stature and a curvature of the spine. This can lead to restrictions in movement. Hyperactivity often leads to problems concentrating. Patients can also suffer from hearing loss, which in the worst case can lead to complete deafness.
Heart defects can also occur as a result of KGB syndrome and reduce life expectancy. A causal treatment of the KGB syndrome is not possible. However, the individual complaints and symptoms can be corrected and treated with the help of various interventions, making everyday life easier for those affected.
When should you go to the doctor?
Patients suffering from KGB syndrome receive comprehensive medical treatment. Therapy begins in childhood and usually continues into adulthood. Parents who notice signs of the disease in their child should speak to the pediatrician as soon as possible. At the same time, the symptoms must be treated. KGB syndrome often causes chronic muscle or bone pain that needs to be treated early. Many of those affected also experience psychological symptoms that require therapeutic advice.
Parents of affected children often also need the help of a psychologist. The doctor can put you in touch with a specialist and, if you wish, refer the family to a self-help group. The actual medical treatment usually lasts for many years and involves a large number of doctors. Depending on the type and severity of the KGB syndrome, cardiologists, ear specialists, speech therapists and neurologists must be consulted. Affected persons should arrange for a clinical examination during pregnancy in order to determine whether the child is inherited at an early stage.
Treatment & Therapy
The treatment of KGB syndrome is primarily aimed at the specific physical and mental symptoms, which can, however, vary greatly from person to person. When this genetic disease is present, close cooperation between paediatricians, orthodontists, neurologists, speech therapists and many others is necessary.
In the course of this cooperation, it is necessary to carefully coordinate these efforts and to create a joint treatment plan as early as possible. By means of a dental treatment that corrects the macrodontia by means of jaw surgery measures, the affected patient’s appearance can be brought closer to a normal picture.
Orthopedic surgeons correct the anomalies of the spine, hips and ribs to prevent later problems due to incorrect posture and the associated incorrect loading. A complete neurological evaluation helps in diagnosing the developmental delays. Early stimulation should start from infancy.
Early speech therapy and special inclusive educational programs mitigate mental defects. Psychopharmacological medication can help with severe behavioral disorders.
Outlook & Forecast
The extent to which those affected can independently improve their quality of life depends on the individual symptoms and complaints. If teeth are misaligned in various ways, the speech quality can be improved not only through surgical treatment, but also through therapy with a speech therapist. The exercises learned can also be continued and intensified in the private sphere.
Targeted exercises help with slight hand abnormalities and the associated difficulties in gripping or holding objects. For example, pens or smaller objects are collected from the table and placed in a bowl, thus training the fine motor skills of the fingers. Intensive physiotherapy, both with a therapist and with exercises you can do yourself, helps to minimize the symptoms of postural damage and, ideally, to get it under control so that further aids such as crutches or wheelchairs can be dispensed with in the long term.
If all of these therapies are used in early childhood and are encouraged by the relatives in their private lives, the affected children have the chance to reduce possible long-term effects as much as possible and enable them to live as normal a life as possible. Visiting self-help groups also helps. When talking to other affected people, a variety of suggestions and tips for making life easier are offered and at the same time worries and needs can be exchanged.
Since the cause of the occurrence of the KGB syndrome is not known and spontaneous mutations have also occurred in a number of the documented cases, it cannot be effectively prevented. However, since autosomal inheritance occurs in some cases, affected persons should arrange for a careful clinical examination by their doctor upon the onset of pregnancy in order to rule out inheritance as early as possible. Unfortunately, a genetic test is not yet available for KGB syndrome.
Follow-up care cannot aim to prevent recurrence of KGB syndrome. The origin has hereditary reasons. Either the disease is present or it is not. This means that scheduled follow-up examinations are assigned different tasks than those encountered, for example, in the case of cancer. Doctors are primarily concerned with keeping complications to a minimum and enabling patients to live a symptom-free everyday life.
To this end, many experts work closely together. Therapies form an essential component of aftercare. How often and how intensively treatments are used depends on the individual clinical picture. General information on appointment intervals is difficult to make. In principle, the need for corrective measures decreases with age because the body is no longer as changeable after the growth phase.
Follow-up care consists of lifelong treatment. Patients can usually lead an independent life if they start therapy early; However, complaints remain. This often includes psychosocial stress. They are best dealt with in regular discussion groups and therapy. It can also happen that those affected are dependent on aids such as crutches or a wheelchair for the rest of their lives. Doctors prescribe these in the same way they prescribe medication for pain management.
You can do that yourself
Which measures patients suffering from KGB syndrome can take themselves depends on the individual symptoms and complaints.
In the case of malpositions in the area of the teeth, speech therapy is indicated to accompany the surgical treatment, which can be supported by those affected at home through regular practice. Aids such as crutches or a wheelchair must be used in the event of poor posture or poor posture. Those affected can alleviate the symptoms by seeking physiotherapeutic advice and consciously maintaining a straight posture. Anomalies in the hands usually require surgery. In less severe cases, specific exercises can also help to practice gripping and holding objects.
If the external abnormalities represent a psychological burden, we recommend visiting a self-help group. In conversations with other sufferers, the sufferers learn tips and tricks for dealing with the disease and can thus better deal with the cosmetic blemishes. In addition to these measures, medical supervision is always necessary. This means that any symptoms can be identified and treated early on, before serious complications develop.