1. 1. What is LHON?

  2. 2. How many people have LHON?

  3. 3. Cause

  4. 4. Diagnosis

  5. 5. Patient Care & Treatments

  6. 6. Research

  7. 7. LHON Confusion



1. What is LHON?


Leber’s Hereditary Optic Neuropathy (LHON) symptoms usually begin as sudden, painless loss of central vision. The classic pattern is for one eye to suddenly lose central vision, then on average 8 weeks later the other eye also loses central vision, though many variations on this pattern are possible.  After this “acute phase,” severe visual loss in both eye remains.  Reading, driving and recognizing faces are impossible.  Peripheral vision generally remains intact so the affected individual can walk around independently.  Since the LHON affected often does not “look blind,”  those around them struggle to understand their situation and don’t realize how profound is their vision loss.  Follow this link for a detailed medical explanation of LHON:

    www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=gene&part=lhon

For a basic medical overview of LHON, view this video:

    www.insidermedicine.com/archives/INSIDERMEDICINE_VIDEO_If_I_Had_Lebers_Hereditary_Optic_Neuropathy_LHON_Dr_Nancy_Newman_Emory_University_3983.aspx

This article also provides a good medical overview:

     http://jmg.bmj.com/content/46/3/145.full



2. How Many People Have LHON?


About 100 people in the United States lose central vision due to LHON each year, joining the 4,000 or so Americans who are already vision impaired due to LHON.  Thousands more carry a LHON genetic mutation, and they could suddenly lose their vision at any time.  It’s estimated that about 35,000 people worldwide have LHON vision.  The most common situation is for LHON vision to affect men around age 15-25.  Women tend to be affected at an older age, often around times of estrogen loss.  LHON vision loss can happen at any age, so if you carry a LHON mutation, you’re never “too young” or “too old” to be affected.  



3. Cause


LHON is a genetic disorder that can cause the optic nerve to atrophy but does not always do so.  It is the most common mitochondrial disease.  About 45 mutations have been linked to LHON.  The most common is the 11778 mutation, accounting for about 50% of all LHON cases.  About 45% of the remaining LHON cases are 14484 or 3460.  A woman carrying a LHON mutation will pass it to all of her children; men with the LHON gene never pass it to their children. Those who have lost their central vision due to LHON are referred to as “affected;” those with a LHON mutation gene but without vision loss are “carriers.” 



4. Diagnosis


Because there is a clear pattern of LHON inheritance, those with a family member on the maternal inheritance chain with LHON should expect that any sudden, painless central vision loss is caused by LHON.  However, carrying the LHON mutation does not mean that a LHON carrier will lose central vision; most who carry the mutation do not.  


Those who are not aware of any family members with LHON are taken by surprise when they suddenly lose central vision.  Since LHON is so rare, the medical community usually suspects and treats for other causes of vision loss.  An MRI may be conducted to rule out a brain tumor.  Since vision loss usually begins in just one eye, the tentative diagnosis of optic neuritis is often made and a 3 or 5 day steroid treatment is usually prescribed.  When vision doesn’t improve and the second eye becomes involved, there may be more tests such as a VER (Visual Evoked Response) and a Lumbar Puncture to rule out other possible causes of sudden vision loss.


A simple blood test for LHON can determine if someone carries one of the primary LHON mutations.  Some labs are for-profit; others are non-profit.  Some test for the 3 primary LHON mutations, other analyze the entire mitochondria.  A list of labs that conduct LHON testing can be found at:

     www.genetests.org/by-disorder/?disid=2450&ps=chld

Genetic counseling with a LHON expert is available by phone at:



                                           



5. Patient Care & Treatments


It is important to find a medical professional who is aware of the most current research regarding LHON, as there has been much new learning in recent years and the condition is so rare that most medical professionals are not up-to-date on recent developments.  Leading centers for LHON research and patient care in the U.S. include:

    USC - Los Angeles, CA

    Emory University - Atlanta, GA

    Bascom Palmer Eye Institute - Miami, FL

Outside the U.S., leading LHON researchers are at:

    University of Bologna - Bologna, Italy

    University of Newcastle upon Tyne - Newcastle, UK

    Royal Victorian Eye & Ear Hospital - Australia

   

It is important to see a neuro-ophthalmologist if LHON is suspected.  Since LHON causes the optic nerve to atrophy, a specialist in this field is most likely to have had experience with LHON.  To find a neuro-ophthalmologist, use this directory of NANOS (North American Neuro-Ophthalmology Society) members.
     http://www.nanosweb.org/i4a/member_directory/feSearchForm.cfm?directory_id=1&pageid=3390&showTitle=1


Another option is to use the Register tab, and request a referral to an experienced LHON doctor. 


Currently there is no approved treatment for LHON.  A clinical trial of Idebenone, a synthetic form of Coenzyme Q10, was undertaken and results of the trial can be found at:

     http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3170530/?tool=pubmed

Additional recent research about this supplement can be found at: 

     http://brain.oxfordjournals.org/content/early/2011/08/02/brain.awr180.short?rss=1

General information about Idebenone is at:

     http://examine.com/supplements/Idebenone

Since LHON is a rare disorder, it may be helpful to discuss these reports with your ophthalmologist, neuro-ophthalmologist or other health professional to determine if this supplement may be right for you, as well as possible side effects.

Idebenone cannot be found in pharmacies, but can be ordered online from companies such as:   www.relentlessimprovement.com.


Many LHON specialists suggest that people carrying a LHON mutation, both carriers and affecteds, avoid environmental factors that could create additional stress on the mitochondria.  These factors include:

  1. -Smoke (all forms - tobacco, woodstoves, bonfires, etc.)

  2. -Alcohol

  3. -Tetracycline

  4. -Minocycline HCL

  5. -Streptomycin

  6. -Erythromycin

  7. -Chloramphenicol

  8. -Ethambutol

  9. -Cyanocobalamin

  10. -Linezolid

  11. -Lactated Ringers (used in some IV’s)

Having a discussion with your own LHON medical professional about these factors is encouraged.  They may wish to obtain and review this article:

     http://link.springer.com/article/10.1007%2Fs11940-010-0100-y


Recent research suggests that estrogen protects women who carry a LHON mutation.  Female LHON carriers may wish to read this article, and discuss its implications with their health care providers.
     http://brain.oxfordjournals.org/content/early/2010/10/13/brain.awq276.full


At the 2013 LHON conference in Newport Beach, CA, Dr. Alfredo Sadun and Dr. Valerio Carelli made very informative presentations about the LHON clinical profile and therapeutic options.  Click on the photos below to watch their presentations.


  


It is important to avoid getting caught up in the hype of for-profit organizations located in China and other countries who offer “stem cell treatments” to “cure” LHON and other disorders.  These organizations are basically “selling hope to desperation”, at about $35,000 per treatment plus the cost of travel to China and staying there a month or so.  There has not been a single scientific, peer-reviewed paper backing up the claims made by these organizations as this type of treatment simply cannot work because:

  1. 1. It’s literally impossible for cells injected either in the blood or CSF (spinal fluid) to get to where they belong in the retina,

  2. 2.There’s no way these cells would know to become Retinal Ganglion Cells (RCG’s), the cells that atrophy in LHON,

  3. 3.Making new RCG’s means nothing if they don’t know where their axons need to connect to.



6. Research


While there is currently no approved treatment and no cure for LHON, there are several research centers around the world where LHON is being studied.  Even though there are relatively few people affected by LHON, there are many researchers working on it because as a mitochondrial disorder it is similar in nature to diseases such as Alzheimer’s, Huntington’s and Parkinson’s, which impact large numbers of patients.  Among the current research is:


Gene therapy - University of Miami [mutation 1178 only]: 

    www.med.miami.edu/news/view.asp?id=1098


Longitudinal study of a large extended LHON family in rural Brazil:

    www.LHON.org/cure

    www.ifond.org/projects.php3





To read the latest research about LHON, go to PubMed and search LHON and related topics:

    www.ncbi.nlm.nih.gov/pubmed


To support LHON research so that a treatment or cure is found as soon as possible, click this Donate button:




7. LHON Confusion


Everything about LHON is confusing...even its name!  Leber’s Hereditary Optic Neuropathy is often referred to by its initials; “L-H-O-N”.  It is also referred to simply as “Leber’s,” (pronounced LAY-bers), the name of the German doctor who first described the disorder (Theodore Leber).  However, that same doctor also described a completely different eye condition called Leber’s Congenital Amaurosis (LCA) which is also genetic in origin but affects the retina not the optic nerve.  The two conditions have nothing in common other than the founding doctor’s name, so it’s important to be sure you’re talking about the ‘right’ Leber’s when someone tells you about something they’ve heard about “Leber’s”.




This website should be considered general information only and should not be considered medical guidance or professional advice.  Always direct any questions concerning your personal health to your doctor or another appropriate health care professional