9th June 2025

Neurofibromatosis Type 1 (NF1)

This is by far the prevalent form of Neurofibromatosis, occurring in over 95% of cases. Its inheritance pattern is autosomal dominant, although 50% of cases are due to de novo mutations. 

Clinical Features 

The cardinal dermatological features of NF1 are:

• Café au lait patches
• Lisch nodules 
• Axillary freckling 

The diagnosis of NF1 is made when there are greater than six café au lait spots and skin tumours.

Image Source: Wikimedia Commons (2006). NF-1-Tache Café-au-lait, Licensed under a creative licence, Available for free at: https://commons.wikimedia.org/wiki/File:NF-1-Tache_cafe-au-lait.jpg (Accessed 23 May 2025).