What are the other Names for this Condition? (Also known as/Synonyms)

• Anterior Basement Membrane Dystrophy
• Cogan Corneal Dystrophy
• Map-Dot-Fingerprint Dystrophy of Cornea

What is Epithelial Basement Membrane Corneal Dystrophy? (Definition/Background information)

• Epithelial Basement Membrane Corneal Dystrophy is a condition where the epithelium of the cornea (the outermost region of the cornea) loses its normal clarity due to a buildup of cloudy material. It gets its name from the unusual appearance of the cornea during an eye exam
• This dystrophy occurs when the epithelium's basement membrane develops abnormally, causing the epithelial cells to not properly adhere to it. This leads to recurrent epithelial erosions, which can cause blurred vision and severe pain
• This condition is usually not inherited. However, families with autosomal dominant inheritance and mutations in the TGFBI gene have been identified

(Source: Epithelial Basement Membrane Corneal Dystrophy; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

Who gets Epithelial Basement Membrane Corneal Dystrophy? (Age and Sex Distribution)

• Epithelial Basement Membrane Corneal Dystrophy is a rare congenital disorder. The exact prevalence of the disorder is not known
• Adults between the ages of 40 and 70 are the most commonly affected, although younger age groups may be affected as well
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Epithelial Basement Membrane Corneal Dystrophy? (Predisposing Factors)

• A positive family history may be an important risk factor, since in rare cases, Epithelial Basement Membrane Corneal Dystrophy can be inherited
• Currently, no other risk factors have been clearly identified for the condition

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Epithelial Basement Membrane Corneal Dystrophy? (Etiology)

• The cause of Epithelial Basement Membrane Corneal Dystrophy is not known in many cases
• Heritable mutations in the TGFBI gene are known in some affected families
• The causative TGFBI gene mutations are inherited in an autosomal dominant manner

Autosomal dominant: Autosomal dominant conditions are traits or disorders that are present when only one copy of the mutation is inherited on a non-sex chromosome. In these types of conditions, the individual has one normal copy and one mutant copy of the gene. The abnormal gene dominates, masking the effects of the correctly function gene. If an individual has an autosomal dominant condition, the chance of passing the abnormal gene on to their offspring is 50%. Children, who do not inherit the abnormal gene, will not develop the condition or pass it on to their offspring.

What are the Signs and Symptoms of Epithelial Basement Membrane Corneal Dystrophy?

The signs and symptoms of Epithelial Basement Membrane Corneal Dystrophy may include:

• Corneal dystrophy
• Map-Dot-Fingerprint Corneal Dystrophy
• Recurrent corneal erosions
• Epithelial erosions, which may cause
  • Periodic blurred vision
  • Moderate to severe pain lasting as long as several days, with the worst pain upon awakening in the morning 
  • Sensitivity to light 
  • Excessive tearing
  • Foreign body sensation in the eye

(Source: Epithelial Basement Membrane Corneal Dystrophy; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

Some individuals with the condition may be asymptomatic

How is Epithelial Basement Membrane Corneal Dystrophy Diagnosed?

Epithelial Basement Membrane Corneal Dystrophy is diagnosed on the basis of the following information:

• Complete physical examination
• Thorough personal and family medical history evaluation
• Assessment of signs and symptoms
• Eye examination slit lamp, with particular focus on the appearance of cornea: The cornea in those affected may have a characteristic “map-dot-fingerprint” appearance that resemble the contours of a geographical map
• Laboratory tests
• Imaging studies
• Biopsy studies, if necessary

(Source: Epithelial Basement Membrane Corneal Dystrophy; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Epithelial Basement Membrane Corneal Dystrophy?

The complications of Epithelial Basement Membrane Corneal Dystrophy may include:

• Excessive tearing
• Temporary vision problems
• Recurrence of the condition after treatment

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Epithelial Basement Membrane Corneal Dystrophy Treated?

Many cases of Epithelial Basement Membrane Corneal Dystrophy may be asymptomatic, and no treatment is necessary. If symptomatic, the following treatments may be recommended:

• Eye patch to immobilize the eye
• Prescription of lubricating eye drops and ointments
• Anterior corneal punctures to allow better adherence of cells
• Corneal scraping to remove eroded areas of the cornea and allow regeneration of healthy epithelial tissue
• Use of the excimer laser to remove surface irregularities

(Source: Epithelial Basement Membrane Corneal Dystrophy; Genetic and Rare Diseases Information Center (GARD) of National Center for Advancing Translational Sciences (NCATS), USA.)

How can Epithelial Basement Membrane Corneal Dystrophy be Prevented?

Currently, Epithelial Basement Membrane Corneal Dystrophy may not be preventable, if it is inherited.

• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

What is the Prognosis of Epithelial Basement Membrane Corneal Dystrophy? (Outcomes/Resolutions)

• The prognosis of Epithelial Basement Membrane Corneal Dystrophy is good, since the condition is not considered to be progressive
• Many of those with the condition may not know that they indeed have the disorder, as they may be asymptomatic
• Even in those who do have symptoms, the condition may flare up occasionally for a few years and resolve on its own or respond well to treatment
• No permanent loss of vision is reported in Epithelial Basement Membrane Corneal Dystrophy

Additional and Relevant Useful Information for Epithelial Basement Membrane Corneal Dystrophy:

Epithelial Basement Membrane Corneal Dystrophy is also known by the following names: 

• Corneal Dystrophy, Anterior Basement Membrane
• Microcystic Dystrophy of the Cornea

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/