Chapter 9: Genodermatoses
Genodermatoses: Neurofibromatosis
Neurofibromatosis
Neurofibromatosis is caused by a mutation in the NF-1 gene that leads to changes in a number of body systems. Several dermatologic findings are among the disease criteria and patients with skin findings concerning for NF should be referred to ophthalmology for examination for Lisch nodules and optic glioma. Referrals to other specialties such as neurology and genetics depend on the presentation and symptoms.
Criteria for NF1 include:
- ≥≥6 café au lait macules >5mm in size in children and >15 mm in size in adults
- ≥2 neurofibromas or any plexiform neurofibroma
- Axillary or inguinal freckling
- Optic glioma
- Lisch nodules
A similar, but distinct, condition called Legius syndrome is caused by mutations in the SPRED-1 gene and leads to development of café au lait macules, but not neurofibromas.
