What is it ?
Recklinghausen’s disease is also called neurofibromatosis type I.
The term “neurofibromatosis” includes a number of genetic diseases affecting the cellular development of neuronal tissues. There are two types of neurofibromatosis: type I and type II. These two forms nevertheless have similar characteristics and are caused by mutations within different genes.
Neurofibromatosis type I is a neurodermal dysplasia, an abnormality in the development of neuronal tissue. This pathology was described for the first time in 1882 by Friederich Daniel Von Recklinghausen, hence the current name of this pathology.
The alterations of the neuronal tissue appear from the embryonic development.
Neurofibromatosis type I is the most common form of neurofibromatosis with 90% of cases being type I. It is also one of the most common human genetic diseases with a prevalence (number of cases in a given population, at a time given) amounting to 1/3 000 births. In addition, no predominance was found between men and women.
Recklinghausen’s disease is a genetic inherited disease whose mode of inheritance is autosomal dominant. That is, which touches a non-sexual chromosome and the presence of only one of the two copies of the mutated gene is sufficient for the subject to develop the disease. This disease is the result of alterations in the NF1 gene located on chromosome 17q11.2.
The characteristics of the disease are defined by:
– “coffee-au-lait” color buttons
– optical gliomas (eye nerve root tumors)
– Lish nodules (hematomas pigmenting the iris of the eyes );
– neurofibromas spinal and peripheral nerve;
– neurological and / or cognitive;
– anomalies on the face;
– malignant tumors of the nerve sheath;
– pheochromocytoma (malignant tumor located in the kidney);
– bone lesions.
Symptoms of Recklinghausen’s disease
Recklinghausen’s disease affects the skin and the central and peripheral nervous system. The associated primary symptoms usually appear in childhood and can affect the skin in the following way:
– cutaneous spots of coffee-milk color, of different sizes, of different shapes and which can be found at any level of the skin. body ;
– freckles developing under the arms and armpits;
– the development of tumors in the peripheral nerves;
– the development of tumors at the level of the nervous network.
Other signs and symptoms may also be significant of the disease, these include:
– Lish nodules: excrescence affecting the eyes;
– a pheochromocytoma: tumor of the adrenal gland, of which ten percent of these tumors are cancerous;
– enlargement of the liver;
– a glioma: tumor of the optic nerve.
The impact of the disease on bone development includes a small build, bone deformities and scoliosis.
The origins of the disease
Recklinghausen’s disease is a genetic inherited disease of the autosomal dominant form. This concerns a non-sexual chromosome whose presence of only one of the two copies of the mutated gene is sufficient in the development of the disease.
The disease is caused by a number of mutations in the NF1 gene, located on chromosome 17q11.2. It is one of the most common spontaneous mutations among all human genetic diseases.
Only 50% of patients with the mutated NF1 gene have a family history in the transmission of the disease. The other part of the patients concerned has spontaneous mutations in this gene.
The expression of the disease is very variable from one individual to another with a panel of clinical manifestations ranging from benignity to more severe complications.
Risk factors for Recklinghausen’s disease
The risk factors for developing the disease are genetic.
Indeed, the transmission of the disease is done by a transfer of the gene NF1 mutated according to the dominant autosomal mode.
Either the mutation in question concerns a gene located on a non-sexual chromosome. In addition, the presence of only one of the two copies of the mutated gene is sufficient for the disease to develop. In this sense, an individual whose parent has the phenotype of the disease has a 50% risk of developing the pathology himself.
Prevention and treatment of Recklinghausen’s disease
The diagnosis of the disease is first of all differential, especially with respect to the presence of certain characteristic symptoms. The primary goal of the physician is to rule out all the possibilities of other diseases involved in these clinical manifestations.
These diseases, whose symptoms strongly resemble those of Recklinghausen’s disease, include:
– Leopard syndrome: a genetic disease whose symptoms also include brown spots on the skin, a space between the eyes widens, a narrowing of the coronary artery , hearing loss, small size and abnormalities in cardiac electrical signals;
– neurocutaneous melanoma: a genetic disease leading to the development of tumor cells in the brain and spinal cord;
schwannomatosis, a rare disease leading to the development of tumors in the nervous tissue;
– Watson syndrome: a genetic disorder that also causes the development of Lish nodules, a small build, neurofibromas, abnormally large head and narrowing of the pulmonary artery.
Additional examinations then make it possible to confirm or not the disease, this is particularly the case with magnetic resonance imaging (MRI) or the scanner.
In the case of a complex disease, the treatment of it must be administered to the various parts of the body concerned.
The treatments prescribed in childhood include:
– assessment of learning abilities;
– evaluation of a possible hyperactivity;
– the treatment of scoliosis and other remarkable deformities.
Tumors can be treated with:
laparoscopic removal of cancerous tumors;
– surgery to remove tumors affecting the nerves;