[Clinical diagnosis of neurofibromatosis type 1].

TO DIAGNOSE NEUROFIBROMATOSIS TYPE 1 (NF1) AND TO DETECT ITS COMPLICATIONS: NF1 is the commonest autosomal dominant (1/3000 à 3500 births). Café au lait spots, axillary and inguinal freckling, hamartomas of the iris (Lisch nodules) and multiple cutaneous neurofibromas, characterize NF1. NF1 can be associated with optic gliomas, spinal or peripheral nerve neurofibromas, macrocephaly, cognitive et neurological disorders, une scoliosis and bone abnormalities. Morbidity and mortality of NF1 are linked to multisystemic complications. In adulthood, diagnosis of NF1 is easy with physical examination: presence of café au lait spots, axillary and inguinal frecklings, neurofibromas. In early childhood, diagnosis can be difficult. Penetrance of the gene is complete by the age of 5 and the diagnosis is made during the follow-up. Clinical examination can easily identify complications such as scoliosis, pseudarthrosis, hypertension linked to renal artery stenosis or phaeochromocytoma or learning disabilities. Annual clinical examination is sufficient for the follow-up of NF1 patients. Screening investigations are not useful because of rare complications, but symptomatic.