Endocrine Abstracts

Neurofibromatosis type 1 is a genetic multisystemic disorder involving the skin, the central and peripheral nervous systems, bones, and the cardiovascular and endocrine systems. We report 2 cases of type 1 neurofibromatosis in 2 patients aged 27 and 23 years respectively. The dermatological lesions (neurofibroma and café au lait spots) were the revealing symptoms. Cerebral MRI revealed a glioma of the optic chiasm developing along the Optic nerves. NF1 has been known for 10 years in the 1st patient, the glioma is stable to differences in imaging controls, after the opinion of the neurosurgeon, radiotherapist and oncologist, simple monitoring is recommended, progress is currently favorable, the search for other lesions is negative. Concerning the youngest patient, the diagnosis of NF1 is recent, the dermatological lesions have been evolving for 3 years, in addition to the glioma, he has a cystic nodular lesion of 18 mm in the pineal region and a delay in stature and Lisch nodules, the search for pheochromocytoma is negative and the abdominopelvic CT scan is without abnormalities, the hormonal assessment is in progress.

Discussion: The gene responsible for NF1 is a tumor suppressor gene, has been located on chromosome 17 in region 17 Q 11, 2. It codes for the protein neurofibromin. Its penetrance is close to 100% at the age of 5 and de novo mutations represent around half of the cases. Neurological manifestations are frequent, exist in half of the cases. 15 to 20% of patients have tumors of the nervous system (gliomas, astrocytomas, neurofibromas). Glioma of benign histology, can sit at any level of the optic pathway, and is expressed by exophthalmos, reduced visual acuity, visual field impairment, precocious puberty by hypothalamic involvement and rarely hydrocephalus, but often asymptomatic and without progression, thus recommending a systematic ophthalmological evaluation (visual examinations, cerebral and orbital MRI) annually mainly in the population of children under 10 years of age and more widely spaced in adults. as well as a systematic search for precocious puberty. The treatment is based on chemotherapy allowing stabilization see tumor reduction. NFI is a genetic disorder responsible for disorders in the differentiation of ectodermal tissue. Despite the discovery of the gene responsible for this disease, the diagnosis remains clinical and is based on defined criteria. Progressive lesions are however very rare and their frequency is very different according to age. In the absence of clinical signs predicting these, clinical monitoring is advised.