Neurofibromatosis, Tuberous Sclerosis & Von Hippel Lindau

Neurocutaneous Syndromes are a group of rare genetic disorders that affect multiple organ systems including the CNS, skin, visual pathway & auditory system. Many benign tumors develop. All of the ones we will cover are autosomal dominant.

Neurofibromatosis:

  • Neurofibromas are tumors of peripheral nerves. They are benign but can cause problems by compressing nearby structures. They usually present just beneath the skin as many rubbery skin colored growths
  • Café-au-lait spots are small light brown macules on the skin. Similar to a birthmark but if there are many it is suggestive of neurofibromatosis
  • Bilateral vestibular schwannomas (bilateral acoustic neuroma) benign tumor of the vestibulocochlear nerve (Cranial nerve 8) that can compress nearby structures and lead to hearing loss
  • Pigmented Iris Hamartomas (Lisch Nodule) which presents as many small areas of pigmentation on the iris (colored part of the eye)
  • Other CNS tumors

Neurofibroma Neurofibromatosis

Pigmented Iris Hamartoma Neurofibromatosis

Cafe Au Lait spot neurofibromatosis

Tuberous Sclerosis:

  • Facial Angiofibromas (adenoma sebaceum)
  • Brain/Cortical Hamartomas called Tubers for which the disease gets its names
  • Subependymal Nodules in the ventricle
  • Renal Angiomyolipomas are tumors made up of vessels, fat and smooth muscle
  • Cardiac Rhabdomyomas
  • Ash Leaf Spots are hypopigmented areas of the skin
  • Seizures
  • Mental Retardation

Tuberous Sclerosis

Von Hippel-Lindau Disease: deletion of the VHL gene

  • Cerebellar and/or Retinal Hemangioblastomas (tumors of capillaries)
  • Renal Cell Carcinoma
  • Cystic lesions of various structures throughout the body

 

Now that you are done with this video you should check out the next video in the Genetics sections which covers Trinucleotide Repeat Expansion, Trisomy 21 & Translocations.

 

Pictures Used (In Order of Appearance)

One thought on “Neurofibromatosis, Tuberous Sclerosis & Von Hippel Lindau”

  1. Thank you so much Brian for the informative videos! i am going to make it a regular part of my study schedule for Step 1. Look forward to more videos along the way!

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