What does L1CAM Syndrome Stand for?

The L1CAM syndrome is a rare hereditary disease. L1CAM syndrome is inherited along an X-linked path. The typical symptoms of L1CAM syndrome are spasticity, an adducted thumb and various brain anomalies in the affected patients.

What is L1CAM Syndrome?

The causes of the L1CAM syndrome can be found in genetic defects. For example, people suffering from the L1CAM syndrome have special genetic mutations that lead to the development of the typical symptoms. See AbbreviationFinder for abbreviations related to L1CAM.

L1CAM syndrome is also known under the synonymous names CRASH syndrome, MASA syndrome and Gareis-Mason syndrome. These are different manifestations of the L1CAM syndrome, which are associated with different symptoms of the hereditary disease. In principle, carriers of the gene defect pass on the L1CAM syndrome to their offspring in an x-linked manner.

The complaints express themselves differently in individual cases. Slight courses as well as serious complications from the L1CAM syndrome are possible. In principle, the L1CAM syndrome is a developmental disorder in the affected patient that is present from birth. A typical feature of the L1CAM syndrome is hydrocephalus, which varies from case to case.

In addition, patients suffering from L1CAM syndrome suffer from mental retardation, adducted thumbs and spasms in the lower extremities. The L1CAM syndrome can be divided into several subtypes, which differ in terms of their main symptoms. MASA syndrome and corpus callosum agenesis are the most relevant.

The L1CAM syndrome dominates in males. The HSAS syndrome occurs with an estimated frequency of approximately 1:30,000. This disease is therefore the most common form of congenital hydrocephalus. The prevalences of the other subtypes of L1CAM syndrome have not been researched.


The causes of the L1CAM syndrome can be found in genetic defects. For example, people suffering from the L1CAM syndrome have special genetic mutations that lead to the development of the typical symptoms. The gene mutations occur on the so-called L1CAM gene, from which the name of the disease is derived.

The mutations are located at the gene locus Xq28. The L1CAM gene is responsible for encoding certain cell adhesion molecules that play a crucial role in the developmental processes of the nervous system. More than 240 different gene mutations are currently known, which explains the diverse symptoms of the L1CAM syndrome. Studies also show that the L1CAM syndrome is caused by new mutations in about seven percent of cases.

Symptoms, Ailments & Signs

The L1CAM syndrome occurs more frequently in men. The patients suffer from hydrocephalus, the severity of which varies from person to person. Mental retardation also varies in severity. Spasms in the lower limbs and generalized hypotension develop at an early age.

The symptoms usually worsen with age, so that atrophy of the muscles in the legs develops. Also typical of the L1CAM syndrome are adducted thumbs, which appear in about half of all patients. Occasionally, people with L1CAM syndrome also suffer from epileptic seizures. L1CAM syndrome is rarely associated with Hirschsprung disease. In female patients, the L1CAM syndrome usually manifests itself in milder symptoms.

Diagnosis & course of disease

The diagnosis of L1CAM syndrome must be made in a specialist center. First, an anamnesis is taken with the patient and his parents, with the focus on the individual symptoms and family anamnesis. After the patient consultation, the doctor uses numerous examination methods, in particular imaging methods.

In male patients with L1CAM syndrome, the diagnosis is also based on neuropathological examinations. An MRI examination is also used as standard. A reliable diagnosis of the L1CAM syndrome is possible using genetic tests that detect mutations in the L1CAM gene.

The differential diagnosis is particularly important. The doctor differentiates the L1CAM syndrome, for example, from spastic paraplegia and other impairments of hydrocephalus. Prenatal diagnosis is possible and useful for female embryos if the relevant gene has occurred in the family. Ultrasonic investigations are also used.


In most cases, the L1CAM syndrome leads to a very severe mental retardation of the patient. As a rule, those affected are then always dependent on the help of other people in their everyday life and can no longer carry out many everyday things on their own. The development of the child is also significantly slowed down and restricted by the L1CAM syndrome, so that there are also considerable consequential damages and complications in adulthood.

As the disease progresses, muscle weakness and epileptic seizures occur. Those affected suffer from severe pain and, in the worst case, can die from the seizures. Those affected can also become victims of bullying or teasing at school. The affected person’s communication and ability to concentrate are also restricted.

Unfortunately, a causal treatment of the L1CAM syndrome is not possible. Those affected are therefore dependent on various therapies that are intended to reduce the symptoms of everyday life. However, complete healing does not occur. In the worst case, the patient may still be born. The life expectancy of those affected can also be reduced by the L1CAM syndrome.

When should you go to the doctor?

Parents who notice their child has spasms or low blood pressure should inform the pediatrician. If the L1CAM syndrome is treated early, the progression of the disease can at least be slowed down. If no treatment is given, the symptoms worsen, eventually leading to muscle weakness and epileptic seizures. At the latest when signs of these symptoms are noticed, specialist medical advice is required. A diagnosed L1CAM syndrome requires permanent treatment.

Affected children must therefore regularly visit a doctor and, depending on the symptoms, various specialists. If seizures, epileptic seizures or falls occur during therapy, the parents must call the emergency services. The child must then be cared for in the clinic, since the seizures can recur within a short time. In addition, any injuries and the causes of the complications must be examined and treated. L1CAM syndrome is treated by a pediatrician, as well as orthopedists, neurologists, internists, and physical therapists. In the event of any psychological complaints, the doctor responsible will also consult a psychotherapist.

Treatment & Therapy

A causal therapy for the L1CAM syndrome is currently not possible, since the disease is caused by genetic mutations and medicine currently has no influence on such disorders. However, the symptoms of the L1CAM syndrome can be treated relatively well symptomatically, depending on the individual case. First, families with cases of L1CAM syndrome seek genetic counseling.

The L1CAM syndrome itself is treated by various specialists, such as neurosurgeons, paediatricians and orthopaedists. The intracranial pressure can be reduced using a liquor shunt. Adducted thumbs usually do not require therapy.

Patients with L1CAM syndrome undergo regular medical check-ups with various specialists to monitor their physical and mental development and to avoid complications. The prognosis of the L1CAM syndrome is highly dependent on the individual severity of the symptoms.

Hydrocephalus can result in a stillbirth or the death of the child at a young age. Less severe symptoms usually lead to a significantly better prognosis for patients with the L1CAM syndrome. The quality of the treatment also affects the course of the L1CAM syndrome.

Outlook & Forecast

The prognosis in patients with a diagnosed L1CAM syndrome is unfavorable. The disease is characterized by irreparable damage that, despite all efforts, cannot be sufficiently changed. The syndrome is based on a genetic defect. Because researchers are legally prohibited from altering human genetics, doctors are left little to treat the symptoms. Although the individual complaints occur with different intensity in each patient, they are nevertheless irreversible and severely impair the lifestyle.

The affected people have a shortened lifespan. There is damage to the brain and thus immense cognitive losses as well as various functional disorders. Coping with everyday life is not possible without therapeutic help and everyday support. Various therapies are used to improve the patient’s quality of life. The disease represents a major challenge for those affected and their families.

Due to the emotional stress, subsequent disorders are to be expected. The L1CAM syndrome has a progressive disease course. In the course of life, further complaints and unpleasant health developments occur. The muscular apparatus is weakened and epileptic seizures occur. In addition, spasticity is part of the clinical picture of the health disorder. Although the administration of medication alleviates the symptoms, there is no recovery.


A causal prevention of the L1CAM syndrome is not yet practicable. The L1CAM syndrome is congenital and arises as a result of genetic mutations. However, genetic counseling is possible for families in which cases of the L1CAM syndrome have occurred or corresponding genetic defects are known. Ideally, the advice is given during family planning, so that the risk of illness for children is reduced.


In most cases, those affected with the L1CAM syndrome have very few, sometimes no aftercare measures available. In the case of this disease, a doctor should be consulted relatively early on, so that the symptoms do not worsen further or other complications occur. As a rule, self-healing cannot occur, so that the person affected with L1CAM syndrome is dependent on medical examination and treatment in any case.

If you wish to have children, you should first undergo a genetic examination and counseling so that the L1CAM syndrome does not recur. Most of those affected by this disease are dependent on various surgical interventions to relieve the symptoms. After such procedures, the person concerned should definitely rest and take care of his body.

Strenuous and physical activities should be avoided, and stress in general should also be avoided. Many of those affected also need psychological support. Contact with other people affected by the L1CAM syndrome can also be useful here. It is not uncommon for information to be exchanged, which can make everyday life easier for the patient.

You can do that yourself

As a rule, the L1CAM syndrome cannot be treated through self-help options, so that patients always depend on medical treatment. However, this can only be symptomatic and not causal.

If the L1CAM syndrome causes the child to be stillborn or die very quickly at a young age, the affected parents need extensive psychological support. Conversations with close friends and relatives help, and contact with other affected parents of L1CAM syndrome can also be helpful and contribute to the exchange of information. Since the patients themselves are extremely restricted in their everyday lives, they are always dependent on loving care from people. The care provided by family and friends in particular has a very positive effect on the course of the disease. Mental retardation can also be counteracted with it. This can possibly be alleviated by various study exercises, which can also be carried out at home.

However, if the L1CAM syndrome causes an epileptic seizure, it must always be examined and treated by a doctor. In general, sufferers depend on regular check-ups with doctors to avoid further complications.