Back of an elderly woman with neurofibromatosis
|Classification and external resources|
Neurofibromatosis (NF) refers to several genetically inherited conditions that are clinically and genetically different and carry a high possibility of tumor formation. This disorder is divided into Neurofibromatosis type 1, Neurofibromatosis type 2 and Schwannomatosis.
Neurofibromatosis (NF1) in early life may cause learning and behavior problems – about 60% of children who have NF1 have a mild form of difficulty in school. In terms of signs the individual might have are the following:
- Six or more light brown dermatological spots (“café-au-lait spots")
- At least two neurofibromas
- At least two growths on the eye's iris
- Abnormal growth of the spine (scoliosis)
Neurofibromatosis is an autosomal dominant disorder, which means only one copy of the affected gene is needed for the disorder to develop. Therefore, if only one parent has neurofibromatosis, his or her children have a 50% chance of developing the condition as well.The affected child could have mild NF1 even though inherited from a parent with a severe form of the disorder. The types of neurofibromatosis are:
- Neurofibromatosis type I, in which the nerve tissue grows tumors (neurofibromas) that may be benign and may cause serious damage by compressing nerves and other tissues.
- Neurofibromatosis type II, in which bilateral acoustic neuromas (tumors of the vestibulocochlear nerve or cranial nerve 8 (CN VIII) also known as schwannoma) develop, often leading to hearing loss.
- Schwannomatosis, in which painful schwannomas develop on spinal and peripheral nerves.
The pathophysiology of neurofibromatosis (type 1) consists of the NF1 gene protein. This protein is a tumor suppressor and therefore serves as a signal regulator of cell proliferation and differentiation. A dysfunction of neurofibromin can affect regulation, and cause uncontrolled cell proliferation. Schwann cells in neurofibromas have a mutation in the NF1 alleles.
The neurofibromatoses are considered as RASopathies and as members of the neurocutaneous syndromes (phakomatoses). Conditions which may be confused with NF-1 but which are not considered NF include, LEOPARD syndrome, and Legius syndrome The diagnosis of neurofibromatosis is done via the following means:
Surgical removal of tumors is an option, however the risks involved should be assessed first. With regard to OPG (optic pathway gliomas), the preferred treatment is chemotherapy. However, radiotherapy isn't recommended in children who present with this disorder. It is recommended that children diagnosed with NF1 at an early age have an examination each year, which allows any potential growths or changes related to the disorder to be monitored.
In most cases, symptoms of NF1 are mild, and individuals live normal and productive lives. In some cases, however, NF1 can be severely debilitating and may cause cosmetic and psychological issues.[medical citation needed] The course of NF2 varies greatly among individuals. In some cases of NF2, the damage to nearby vital structures, such as other cranial nerves and the brain stem, can be life-threatening. Most individuals with schwannomatosis have significant pain. In some extreme cases the pain will be severe and disabling.
NF1 occurs in 1 in 3000 individuals and is equally prevalent among men and women. Furthermore, it is among the most common inherited nervous system disorders. Such individuals have a 10 to 15 year reduction in life expectancy compared to the average person.
- Evans, Rosalie E. Ferner, Susan M. Huson, D. Gareth R. (2011). Neurofibromatoses in clinical practice. London: Springer. p. 15 (introduction). ISBN 978-0-85729-628-3. Retrieved 9 October 2015.
- "Learning about Neurofibromatosis". www.genome.gov. Retrieved 2015-10-10.
- "Neurofibromatosis". NHS Choices. NHS. Retrieved 9 October 2015.
- "Neurofibromatosis". NINDS. NIH. Retrieved 9 October 2015.
- "NINDS Neurofibromatosis Information Page". 23 February 2015. Retrieved 2015-04-21.
- Choices, NHS. "Neurofibromatosis type 1 - Causes - NHS Choices". www.nhs.uk. Retrieved 2015-10-09.
- "Neurofibromatosis type 1". Genetics Home Reference. 2015-10-05. Retrieved 2015-10-09.
- "Neurofibromatosis type 2". Genetics Home Reference. 2015-10-05. Retrieved 2015-10-09.
- Perry, Arie; Brat, Daniel J. (2010-01-01). Practical Surgical Neuropathology: A Diagnostic Approach. Elsevier Health Sciences. p. 435. ISBN 0443069824.
- "Orphanet: Neurofibromatosis type 1". www.orpha.net. Retrieved 2015-10-13.
- Boyd, Kevin P.; Korf, Bruce R.; Theos, Amy (July 2009). "Neurofibromatosis type 1". Journal of the American Academy of Dermatology. 61 (1): 1–14. doi:10.1016/j.jaad.2008.12.051. PMC . PMID 19539839.
- Conrad Fischer; Farshad Bagheri; Rajpal Manchandani; Richard Pinsker; Sudheer Chauhan; Parenkumar Patel; Mohammad Maruf; Dhaval Satani; Kaushik Doshi; Ayaz Alwani; Naveen Pathak; Craigh Thurm; Mohammad Babury; Mahendra C. Patel; Arthur Shalanov; Samir Sarkar; Sabiha Raouf; Jebun Nahar; Prakashkumar Patel (2010). Master the Board USMLE Step 2 CK. KAPLAN Medical. p. 287. ISBN 978-1-60714-653-7.
- Friedman, J. M. (2014). Pagon, Roberta A.; Adam, Margaret P.; Ardinger, Holly H.; Wallace, Stephanie E.; Amemiya, Anne; Bean, Lora JH; Bird, Thomas D.; Dolan, Cynthia R.; Fong, Chin-To, eds. Neurofibromatosis 1. Seattle (WA): University of Washington, Seattle. PMID 20301288.
- Stevenson, David; Viskochil, David; Mao, Rong (2015). Pagon, Roberta A.; Adam, Margaret P.; Ardinger, Holly H.; Wallace, Stephanie E.; Amemiya, Anne; Bean, Lora JH; Bird, Thomas D.; Dolan, Cynthia R.; Fong, Chin-To, eds. Legius Syndrome. Seattle (WA): University of Washington, Seattle. PMID 20945555.
- "Neurofibromatosis. What is neurofibromatosis? Type 1 (NF1) | Patient". Patient. Retrieved 2015-10-09.
- Choices, NHS. "Neurofibromatosis type 2 - Treatment - NHS Choices". www.nhs.uk. Retrieved 2015-10-11.
- "Complex Neufibrmatosis type 1" (PDF). NHS.uk. NHS. Retrieved 13 October 2015.
- Choices, NHS. "Neurofibromatosis type 1 - Treatment - NHS Choices". www.nhs.uk. Retrieved 2015-10-11.
- Norden, Andrew D.; Reardon, David A.; Wen, Patrick Y. (2010-12-16). Primary Central Nervous System Tumors: Pathogenesis and Therapy. Springer Science & Business Media. p. 459. ISBN 9781607611660.
- Runge, Marschall S.; Patterson, Cam (2007-11-18). Principles of Molecular Medicine. Springer Science & Business Media. p. 1160. ISBN 9781592599639.
|Wikinews has related news: Interview with Reggie Bibbs on his life with neurofibromatosis|
- Poyhonen, M.; Kytölä, S.; Leisti, J. (2000-08-01). "Epidemiology of neurofibromatosis type 1 (NF1) in northern Finland". Journal of Medical Genetics. 37 (8): 632–636. doi:10.1136/jmg.37.8.632. ISSN 1468-6244. PMC . PMID 10991696.
- Upadhyaya, Meena; Cooper, David (2013-01-29). Neurofibromatosis Type 1: Molecular and Cellular Biology. Springer Science & Business Media. ISBN 9783642328640.
- Schmucker, Beatrice; Tang, Yong; Kressel, Michael (1999-08-01). "Novel Alternatively Spliced Isoforms of the Neurofibromatosis Type 2 Tumor Suppressor Are Targeted to the Nucleus and Cytoplasmic Granules". Human Molecular Genetics. 8 (8): 1561–1570. doi:10.1093/hmg/8.8.1561. ISSN 0964-6906. PMID 10401006.