Neurofibromatosis Type 1

Genetic condition that causes tumours along the nervous system

Aetiology

• Mutation in NF1 gene

• Relatively common - 1: 3000 individuals

Clinical presentation

• ≳6 cafe-au-lait macules

• ≳ neurofibromas of any type, or one plexiform neurofibroma - the neurofibroma is the major NF-1 associated tumour

• Axillary or inguinal freckling

• Optic glioma

• ≳2 Lisch nodules

• Distinctive osseous lesion e.g. sphenoid dysplasia or thinning of long bone cortex, with or without pseudoarthrosis

• First degree relative with NF1

Other clinical features

• Scoliosis

• Can cause learning difficulties

• Phaeochromocytoma (rare)