[Neurofibromatosis type 1: a survey of 195 patients].

OBJECTIVE: To analyse symptoms and complications in patients with neurofibromatosis type 1 (NF1). All patients were examined in a multidisciplinary outpatient neurofibromatosis clinic during a period of 10 years. DESIGN: Retrospective. SETTING: Academic Medical Center, University Hospital Amsterdam, the Netherlands. METHOD: All data on 450 persons visiting the neurofibromatosis clinic were stored in a database. Data were collected on the results of dermatological, neurological, ophthalmological and general examinations and on family history. For this study the follow-up data of 196 patients with a definite diagnosis of 'NF1' were analysed. RESULTS: In childhood diagnosis NF1 is predominantly based on specific dermatological symptoms such as > 6 café-au-lait (CAL) spots and freckling and on the presence of characteristic ophthalmological signs as two or more Lisch nodules. In this study the frequencies of these symptoms were 98% (CAL). 92% (freckles), and 93% (Lisch nodules) respectively. The frequencies of well-known complications of this disorder are comparable with the literature findings. In this study we found optic pathway glioma (OPG) in 10%, macrocephaly in 36%, hydrocephalus in 5%, retardation in 14%, brain tumours in 5%, kyphoscoliosis in 13%. renal artery stenosis in 0.5% and neurofibrosarcoma in 0.5% of NF1 patients. In children the degree of severity of this disorder is less than in adults, demonstrating the progressive character of the disease. CONCLUSION: The diagnosis of 'NF1' can usually be made by dermatological and ophthalmological examination. In case of a definite diagnosis in childhood regular follow-up is recommended since severe complications, such as OPG and kyphoscoliosis, may occur specifically in childhood and adolescence. For adult patients determination of the degree of severity is essential for the decision whether or not they need regular follow-up; they should have their blood pressure measured annually.