Neurofibromatosis Flashcards
What is Neurofibromatosis?
autosomal dominant genetic disorder affecting cells of neural crest origin, resulting in development of multiple neurocutaneous tumours
What is type 1 neurofibromatosis characterised by?
Peripheral + spinal neurofibromas Multiple café au lait spots Freckling (axillary/ inguinal) Optic nerve glioma Lisch nodules (on iris) Skeletal deformities Phaeochromocytomas Renal artery stenosis
What is type 2 neurofibromatosis characterised by?
Schwannomas (often bilateral vestibular schwannomas)
Meningiomas
Gliomas
Cataracts
What is neurofibromatosis associated with?
Multiple mutations in tumour suppressor genes NF1 (type 1) + NF2 (type 2)
Describe the epidemiology of neurofibromatosis
No gender or racial predilection Positive FH (but 50% are caused by new mutations)
List 5 features of the patient history in type 1 neurofibromatosis
Skin lesions Learning difficulties (40%) Headaches Disturbed vision (due to optic gliomas) Precocious puberty (due to lesions of the pituitary gland from an optic glioma involving the chiasm)
List 6 features of the patient history in type 2 neurofibromatosis
Hearing loss Tinnitus Balance problems Headache Facial pain Facial numbness
List 6 signs of type 1 neurofibromatosis
5+ café au lait macules of > 5 mm (prepubertal)
5+ café au lait macules of > 15 mm (post-pubertal)
Neurofibromas (cutaneous nodules or complex plexiform neuromas)
Freckling in armpit or groin
Lisch nodules (hamartomas on the iris)
Spinal scoliosis
What investigations should be performed for neurofibromatosis?
Ophthalmological assessment Audiometry MRI brain + spinal cord - for vestibular schwannomas, meningiomas + nerve root neurofibromas Skull X-ray (sphenoid dysplasia in NF1) Genetic testing
What is Type 1 neurofibromatosis also known as?
Von Recklinghausen’s disease
Give 2 signs of type 2 neurofibromatosis
Few or no skin lesions
Sensorineural deafness with facial nerve palsy or cerebellar signs (if the schwannoma is large)