Conradi-Hünermann syndrome is the term used in human medicine when a female patient is diagnosed with an extremely rare growth deficiency due to genetic causes. This is manifested, among other things, by low hairiness, shortened limbs, excessively large skin pores and other morphological defects. The syndrome cannot be cured, but only treated symptomatically.
What is Conradi-Hünermann syndrome?
Conradi-Hünermann syndrome is a genetically caused abnormality of growth that occurs exclusively in girls. Affected individuals suffer from massive morphological abnormalities. These are externally visible by shortened limbs, markedly large skin pores and low hairiness. A deformed face and other defects of the body are also possible. The disease was named after its discoverers, the German pediatricians Erich Conrad, Carl Hünermann and Rudolf Happle. In the literature, the terms Happle syndrome, Conradi-Hünermann-Happle syndrome, and the Latin names chondrodystrophia congenita calcificans and chondrodysplasia foaetalis calcarea can also be found. According to the ICD-10 classification, the name chondrodysplasia punctata syndrome can also be used. Since the disease affects the chondrodysplasias, it belongs to the group of chondrodysplasia punctata. Typical for representatives of this group is calcification of larynx, trachea or joints. Today, it is possible to diagnose the complex diseases of this group already in the womb. In the medical literature, the frequency of Conradi-Hünermann syndrome is estimated at about one in 100,000 births. Thus, the disease is extremely rare.
Causes
Conradi-Hünermann syndrome is due exclusively to genetic causes. Differentiation from other diseases of the chondrodysplasia punctata group is based on the genetic defect that causes the symptoms that occur in each case and the relevant mode of inheritance. Thus, in contrast to other diseases, Conradi-Hünermann syndrome is inherited through a dominant X chromosome. This has a defective EBP gene and thus causes the typical morphological abnormalities. The EBP gene is also known as sterol delta8/7 isomerase and is an enzyme found in cholesterol metabolism. Among other things, it is responsible for the rearrangement of double bonds and is mutated in the chromosomal region Xp 11.23 – p 11.22 in affected girls.
Symptoms, complaints, and signs
The different manifestations of Conradi-Hünermann syndrome turn out differently, so not all of the symptoms listed below need to be present. Often, affected individuals present with only some of the symptoms that are conceivable in their entirety. For example, considerable morphological abnormalities of the face are common. In many of those affected, the face is very flat and characterized by a particularly flattened bridge of the nose. In addition, changes in the eyes are among the typical symptoms of Conradi-Hünermann syndrome. The most common symptoms include clouding of the eye lens (cataract), loss or severe reduction of the nerve fibers of the eye (glaucoma), and degenerative damage to the optic nerve, which is manifested by a decrease in the number of nerve cells (optic atrophy). In addition, severe shortening of the extremities can occur, which is why the syndrome is often referred to as a growth disorder. Especially the arms and legs are affected. They are partly asymmetrical. Differences in length are also not unusual. In addition, restrictions in the functionality and mobility of the joints are also a common symptom (joint contracture). Kyphosis or scoliosis is also often reported. Kyphosis is understood as a backward (dorsal) curvature of the spine. A lateral deviation of the same is called scoliosis. In addition, skin changes are common. Affected individuals have large pores. Ichthyosis (ichthyosis), pigmentary disorder, erythdroderma and atrophoderma are also common.
Diagnosis and course
The first diagnosis is possible to modern human medicine in the womb and therefore very early. Detection can be achieved by an x-ray. This usually shows some abnormalities. For example, calcifications in the ends of the joints, the so-called epiphysis ossis, may be visible, especially in the early years of life.The calcifications are visible as stippled on the X-ray image. In addition, a vertebral body that is reduced in height and shortening of the limbs are typical. Particularly in older patients, a purely visual examination can already lead to an initial finding. However, since Conradi-Hünermann syndrome must be distinguished from the other representatives of the chondrodysplasia punctata group, a comprehensive differential diagnosis will always be necessary. Other conceivable causative agents of the symptoms that are not related to the syndrome should also be excluded.
Complications
Various symptoms and complications may occur with corpus callosum agenesis. In most cases, however, there are behavioral disturbances and limitations in hearing and vision. Usually, the limitations do not appear suddenly, but lead to a constant reduction of these perceptions during the course of the disease. Complete blindness or complete hearing loss may also occur. Due to the increased brain pressure, in many cases there are headaches and maldevelopments in the brain. Due to these maldevelopments, behavioral disorders and other psychological complaints occur. Often, corpus callosum agenesis also occurs with short stature. Patients suffer from metabolic disorders and have a reduced quality of life. Concentration is also reduced, so there is usually decreased intelligence. Causal treatment is not possible because it is not possible to replicate the brain bar. For this reason, mainly behavioral therapies and learning therapies are used so that the patient’s intelligence is not reduced by the corpus callosum agenesis. Speech therapy must also be performed in many cases. If epileptic seizures occur, brain pressure must be reduced. In rare cases, corpus callosum agenesis does not cause any symptoms or complications.
When should you see a doctor?
When the morphologic abnormalities of the face or other typical symptoms of Conradi-Hühnerman syndrome are noticed, a physician must be consulted in any case. In case of noticeable symptoms like the characteristic cataract or growth disorders, there is a high probability that it is the genetic disease – then one should immediately talk to the pediatrician. Conradi-Hühnerman syndrome is a hereditary disease that occurs mainly in females. Parents who notice symptoms mentioned in their child or have a concrete suspicion of a disease due to a family history should consult a physician immediately. In general, unusual symptoms and external abnormalities should be clarified quickly so that they can be treated at an early stage. Therefore: if you have a mere suspicion or characteristic signs of the disease, go to your family doctor or pediatrician. Further contacts are the specialist for hereditary diseases and specialists for the respective symptoms. For example, an ophthalmologist should be consulted for vision problems, while growth disorders require orthopedic help. In a medical emergency, emergency medical services should be contacted.
Treatment and therapy
Because Conradi-Hünermann syndrome presents as a genetic disorder that leads to morphologic changes even in the embryonic stage, a cure is not possible. Accordingly, all therapeutic approaches have a symptomatic focus. The aim is therefore to alleviate the symptoms of the disease. For example, changes in the skin can be alleviated by ointments. Differences in leg length require orthopedic treatment. Changes or malpositions of the spine can also be treated by wearing a corset. Medications are prescribed for the treatment of potentially occurring pain. Physiotherapy or physiotherapeutic concepts can form a helpful complementary element of a comprehensive and in itself coordinated therapy concept.
Outlook and prognosis
As a rule, Conradi-Hünermann syndrome cannot be treated causally. For this reason, only symptomatic treatment of the syndrome is possible, so there is no complete cure. If Conradi-Hünermann syndrome is not treated, those affected suffer from various facial deformities, which can have a negative effect on the patient’s aesthetics.A growth disorder also occurs, with the arms and legs being primarily affected by this disorder. The difference in length can also lead to restrictions in movement and thus in everyday life. In general, Conradi-Hünermann syndrome has a very negative effect on the child’s development and slows it down. The patient’s vision is also reduced by the syndrome, with complete vision loss occurring in the worst cases. Treatment of Conradi-Hünermann syndrome can primarily compensate for the changes in the skin and spine. A corset can be used to alleviate the spinal deformity. Physiotherapy or physical therapy can also alleviate pain. Prevention of Conradi-Hünermann syndrome is not possible. However, the patient’s life expectancy is usually not negatively affected by the disease.
Prevention
Conradi-Hünermann syndrome is caused by a defective chromosome. The disease is thus exclusively genetic, making prevention entirely impossible.
Aftercare
Because genetic Conradi-Hünermann syndrome or Happle syndrome is associated with growth disturbances, multiple visits to the doctor are the norm at a young age. Medical treatment can only be symptomatic due to the genetic cause of Conradi-Hünermann syndrome. However, in addition to necessary medical measures resulting from the clinical picture, aftercare measures are also helpful. One of the important measures of aftercare is support services of psychological nature. The immediate environment should be informed about the nature of the disease in order to avoid bullying and ridicule because of the special appearance of the affected person. The use of meditation, relaxation methods or yoga can also help those affected to cope better with the consequences of the disease. Participation in a self-help group can be an important measure in the context of aftercare. Both the sufferers themselves and their immediate relatives can receive help, advice and support here. Meaningful and fulfilling leisure activities are just as much a part of Conradi-Hünermann syndrome as regular exercise. Within the scope of their physical possibilities, those affected can take part in disabled sports. This also ensures that a supportive social environment is created in which those affected feel accepted. On the medical aftercare side, not too much can be done for Conradi-Hünermann syndrome. However, physiotherapy and other physiotherapeutic measures that maintain mobility are possible. Such measures also help relieve pain.
What you can do yourself
Since strong noticeable visual changes are associated with the symptoms of the hereditary disease, the affected person should pay attention to strengthening his self-confidence. In everyday life, despite all the discomfort, good psychological stability is important for maintaining a good quality of life. To ensure that dealing with the disease is not associated with surprises or unpleasant situations for the person affected and the people in their social environment, good information should be provided about the disease and its course. This facilitates interpersonal interaction. It is helpful to create a relaxed atmosphere in which people can talk openly about the disease and clarify open questions. Prejudices and inhibitions can be reduced in this way. For mental strengthening, relaxation methods can be used, which can be carried out independently at any time. Meditation, yoga or progressive muscle relaxation help to reduce stress and clear the mind. Self-help groups are also frequently found to be helpful. Here, sufferers exchange information and give each other support and important advice. Despite the serious symptoms, leisure and sporting activities help to maintain and build up a sense of well-being. Considering the physical possibilities, participation in social life is important for mental health. In contact with other people fears can be reduced and the joy of life can be lived.
