Neurofibromatosis

What is Neurofibromatosis ?

• It is part of the phacomatoses and different forms exist.
• It is inherited in an autosomal dominant fashion.

What are the types of neurofibromatosis and what do they look like ?

• Neurofibromatosis type 1 (NF1) is called Von Recklinghausen’s Disease:

1. It is most frequently associated with cutaneous alterations.
2. It is caused by a mutation on chromosome 17.
3. Skin changes present in NF1 include:
4. Neurofibromas: these present as rounded promenine flesh-like bumps.
5. Café-au-lait macules: big tan patches
6. Axillary freckling (also called Crowe’s Sign): small lentigenes in the armpits.
7. Itching may be present.
8. Internal signs include:
9. Lisch nodules: these are proliferations of scar-like tissue in the iris of the eyes
10. Skeletal changes (scoliosis…) and tumors in the brain. Therefore imagery is necessary (Radiography, MRI scan (Magnetic Resonance Imagery), CT scan (Computed Tomography).
11. Hypertension

• Neurofibromatosis type 2 (NF2) is characterized by bilateral masses in the inner ear (called Schwannomas):

1. It is caused by a mutation of chromosome 22.
2. Skin changes are the same as in NF1, homever, they are less proment.

How to treat ?

• Prenatal counseling is strongly recommended as therapeutical options are quite limited.
• Tumors need to be monitored for malignant changes and  surgery may be needed. For NF2 even after surgery of the inner hear, balance and hearing problems can persist.
• Hypertension and scoliosis can be treated.
• Bothersome neurofibromas may be removed by CO2 laser or electrocauthery.
• Pruritus often responds well to ketotifen.

Bibliography: Sterry W. et al. Thieme Clinical Companions: Dermatology. 1st edition in English