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Disease Profile

Adult-onset vitelliform macular dystrophy

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

Unknown

US Estimated

Europe Estimated

Age of onset

Adult

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ICD-10

H35.5

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

AVMD; Macular dystrophy, vitelliform, adult-onset; Vitelliform macular dystrophy, adult-onset;

Categories

Congenital and Genetic Diseases; Eye diseases

Summary

Adult-onset vitelliform macular dystrophy (AVMD) is an eye disorder that can cause progressive vision loss. AVMD affects an area of the retina called the macula, which is responsible for sharp central vision. The condition causes a fatty yellow pigment to accumulate in cells underlying the macula, eventually damaging the cells.[1] AVMD usually begins after age 40. Some people remain without symptoms throughout their life. Other people with AVMD may slowly develop blurred and/or distorted vision, that can progress to central vision loss over time.[1][2] In the past, AVMD was believed to be mainly a genetic disorder caused by mutations in the PRPH2BEST1, IMPG1, and IMPG2 genes; however, recent studies focused on genetic testing suggest that the genetic cause for most cases of AVMD has not been found.[2][3] Sometimes AVMD clearly runs in families in an autosomal dominant manner, but the inheritance is suspected to be more complicated in the majority of cases. [1][2]

Symptoms

Signs and symptoms of adult-onset vitelliform macular dystrophy typically begin during mid-adulthood, in the fourth or fifth decade of life. At the time of diagnosis, mild blurring or mildly distorted vision may be present. In most cases, the cells underlying the macula become more damaged over time, which can cause slowly progressive vision loss. The condition is usually affects both eyes.[2][3] It usually does not affect peripheral vision or the ability to see at night.[1]

Studies have revealed much variability in the signs, symptoms and progression of this condition. Some people with AVMD do not have any visual symptoms throughout their life. Others may experience ongoing visual loss, but for most people the vision loss is not severe. In general, the long-term outlook (prognosis) is usually good, but loss of central visual function is possible.[2][3]

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Vitelliform-like macular lesions
0007677
30%-79% of people have these symptoms
Choroideremia
0001139
Color vision defect
Abnormal color vision
Abnormality of color vision

[ more ]

0000551
Iris hypopigmentation
Light eye color
0007730
Visual field defect
Partial loss of field of vision
0001123
5%-29% of people have these symptoms
Retinal nonattachment
0007899
1%-4% of people have these symptoms
Choroidal neovascularization
0011506
Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance
0000006
Drusen
0011510
Macular atrophy
0007401
Macular dystrophy
0007754
Metamorphopsia
0012508
Photophobia
Extreme sensitivity of the eyes to light
Light hypersensitivity

[ more ]

0000613
Reduced visual acuity
Decreased clarity of vision
0007663

Cause

Historically, adult-onset vitelliform macular dystrophy (AVMD) was defined as a genetic disorder; however, recent studies have concluded that only a minority of cases have an identified genetic cause, suggesting that there might be other underlying causes of environmental origin, genetic origin, or a mix of genetics and environment (multifactorial). More studies are needed to better define other underlying causes that might be present, whether of genetic or environmental origin.[2][3]

Currently known genetic causes include mutations in the PRPH2BEST1IMPG1, and IMPG2 genes. It is additionally suspected that AVMD might be associated with a single-nucleotide polymorphism (variant DNA sequence) in the HTRA1 gene. Singlenucleotide polymorphisms in the HTRA1 gene are additionally associated with age-related macular degeneration.[2][3]

Diagnosis

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.
  • Orphanet lists international laboratories offering diagnostic testing for this condition.

    Treatment

    There is no cure or known treatment to stop the progression of adult-onset vitelliform macular dystrophy.[2] Management usually includes a comprehensive eye examination once or twice a year to monitor progression of the disease and for complications such as choroidal neovascularization (CNV).[4] 

    CNV is sometimes associated with adult-onset vitelliform macular dystrophy because macular degeneration can damage the retinal layers. When this happens, the vascular layer of the eye between the sclera and the retina known as the choroid may produce new blood vessels (neovascularization) which grow up through the damaged layers and leak or bleed into the retina. This can cause vision loss on its own. If CNV does develop, anti-VEGF therapy such as Ranibizumab or Bevacizumab can control and even reverse the CNV. However anti-VEGF therapy does not stop or reverse the vision loss caused by adult-onset vitelliform macular dystrophy, only the extra vision loss that is due to also developing CNV.[2] 

    Although vision loss is usually slow, when vision is impaired significantly, people with adult-onset vitelliform macular dystrophy may be referred for low vision testing and rehabilitation. Low vision rehabilitation can help maintain and optimize reading ability and improve overall quality of life.[4][5]

    Organizations

    Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

    Organizations Supporting this Disease

      Organizations Providing General Support

        Learn more

        These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

        Where to Start

        • MedlinePlus Genetics contains information on Adult-onset vitelliform macular dystrophy. This website is maintained by the National Library of Medicine.

          In-Depth Information

          • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
          • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
          • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
          • PubMed is a searchable database of medical literature and lists journal articles that discuss Adult-onset vitelliform macular dystrophy. Click on the link to view a sample search on this topic.

            References

            1. Vitelliform macular dystrophy. Genetics Home Reference. December 2013; https://ghr.nlm.nih.gov/condition/vitelliform-macular-dystrophy.
            2. Chowers I, Tiosano L, Audo I, Grunin M, Boon CJ. Adult-onset foveomacular vitelliform dystrophy: A fresh perspective. Progress in Retinal and Eye Research. February 2015; 47:64-85. https://www.ncbi.nlm.nih.gov/pubmed/25681578.
            3. Tiosano L, Grunin M, Hagbi-Levi S, Banin E, Averbukh E, Chowers I. Characterising the phenotype and progression of sporadic adult-onset foveomacular vitelliform dystrophy. British Journal of Opthalmology. November, 2016; 100(11):1476-1481. https://www.ncbi.nlm.nih.gov/pubmed/26802173.
            4. Chan, S and Macdonald I. Adult-onset foveomacular vitelliform dystrophy. Orphanet. December 2013; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=99000.
            5. Grenga PL, Fragiotta S, Cutini A, Meduri A, Vingolo EM. Microperimetric evaluation in patients with adult-onset foveomacular vitelliform dystrophy. Indian Journal of Ophthalmology. 2017;65(5):. May 2017; 65(5):385-389. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5565886/.

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