X-linked exudative vitreoretinopathy 2

X-linked Exudative Vitreoretinopathy 2 (EVR2; FEVRX)

X-linked exudative vitreoretinopathy 2, also known as EVR2 or FEVRX, is a rare inherited disorder characterized by the incomplete development of the retinal vasculature. This condition affects the retina, the light-sensitive tissue that lines the back of the eye.

Key Features:

• Inherited Disorder: X-linked exudative vitreoretinopathy 2 is an inherited disorder, meaning it is passed down from parents to offspring through a mutated gene.
• Incomplete Retinal Vasculature: The primary anomaly in EVR2 is peripheral avascularity due to defective retinal angiogenesis, leading to sight-threatening features such as hyperpermeable blood vessels, neovascularization, vitreoretinal traction, retinal folds, and detachments.
• Variable Clinical Appearance: Even within families, the clinical appearance of EVR2 can vary considerably, with severely affected patients often registered as blind during infancy, whereas mildly affected patients may have few or no visual problems.

Genetic Basis:

• X-linked Recessive Pattern: When caused by variants in the NDP gene, X-linked exudative vitreoretinopathy 2 has an X-linked recessive pattern of inheritance.
• NDP Gene Mutation: The NDP gene mutation is located on the X chromosome and can cause progressive vision loss.

Staging:

• Stage 1: Avascular peripheral retina
• Stage 2: Retinal neovascularization (with or without exudate)
• Stage 3: Extramacular retinal detachment (with or without exudate)

The information provided above is based on the following search results:

[1] Familial exudative vitreoretinopathy (FEVR) is an inherited disorder characterized by the incomplete development of the retinal vasculature. [2] Exudative vitreoretinopathy 2, X-linked (EVR2; FEVRX) MedGen UID: 337030 ... [11] When familial exudative vitreoretinopathy is caused by variants in the NDP gene, it has an X-linked recessive pattern of inheritance. [12] with X-linked mutations of NDP and presents with ocular manifestations similar to those noted in FEVR. [14] Familial exudative vitreoretinopathy (FEVR) is a hereditary disorder that can cause progressive vision loss. This condition affects the retina, the light-sensitive tissue that lines the back of the eye, by preventing blood vessels from forming at the edges of the retina.

X-linked exudative vitreoretinopathy (FEVR) is a rare inherited disorder that affects the development of retinal blood vessels. The signs and symptoms of this condition can vary widely, even within families.

Common Signs and Symptoms:

• Retinal detachment: This is one of the most common complications of X-linked FEVR, where the retina separates from the back of the eye.
• Vision loss or blindness: In severe cases, patients may be registered as blind during infancy or early childhood.
• Strabismus (crossed eyes): This can occur due to the abnormal development of retinal blood vessels.
• Leukocoria (white reflex in the pupil): A visible whiteness in the normally black pupil, which can be a sign of retinal detachment or other complications.

Other Possible Signs and Symptoms:

• Retinal folds: The retina may fold or become distorted due to the abnormal development of blood vessels.
• Enophthalmos (sunken eye): In advanced cases, patients may experience a sunken appearance of the eye.
• Phthisis (shrinkage of the eyeball): This is a rare complication where the eyeball shrinks due to the detachment of the retina.

Variability in Signs and Symptoms:

It's essential to note that the signs and symptoms of X-linked FEVR can vary widely, even within families. Some patients may experience severe vision loss or blindness, while others may have few or no visual problems despite having a small area of avascularity in the retina [14][15].

References:

• [13] A four-generation family with X-linked FEVR is described, highlighting the variability in signs and symptoms.
• [14] The clinical appearance of X-linked FEVR varies considerably, even within families.
• [15] This inherited disorder is characterized by the incomplete development of retinal vasculature.

Based on the provided context, diagnostic tests for X-linked exudative vitreoretinopathy 2 (EVR2) include:

• Clinical Molecular Genetics test: This test is specifically designed to diagnose Exudative vitreoretinopathy 2, X-linked. It involves sequence analysis of the entire coding region and next-generation sequencing (NGS)/massively parallel sequencing (MPS).
• Genetic testing: Genetic testing can aid in confirming the diagnosis of FEVR, including EVR2. This may involve analyzing the NDP gene, which is associated with Norrie disease and EVR2.
• Sequence analysis of the entire coding region: This test is used to identify mutations in the NDP gene that are associated with EVR2.
• Next-Generation (NGS)/Massively parallel sequencing (MPS): This advanced sequencing technology is used to analyze the genetic material and identify any mutations or variations that may be causing the condition.

It's worth noting that a diagnosis of FEVR, including EVR2, is often based on a combination of clinical features, family history, and genetic testing. A comprehensive evaluation by an ophthalmologist and/or a geneticist is typically necessary to confirm the diagnosis.

References:

• [10] Clinical Molecular Genetics test for Exudative vitreoretinopathy 2, X-linked and using Sequence analysis of the entire coding region, Next-Generation (NGS)/Massively parallel sequencing (MPS) offered by Bioarray.
• [3] The gene for autosomal dominant familial exudative vitreoretinopathy (Criswick-Schepens) on the long arm of chromosome 11. Am J Ophthalmol. 1992;113(6):712-3.

Treatment Options for X-linked Exudative Vitreoretinopathy 2

X-linked exudative vitreoretinopathy 2 (EXVR2) is a rare inherited disorder characterized by incomplete development of the retinal vasculature. While there are no specific treatments that can cure EXVR2, various therapeutic approaches have been explored to manage its symptoms and slow disease progression.

Anti-VEGF Therapy

One potential treatment for EXVR2 is anti-VEGF (vascular endothelial growth factor) therapy. This approach involves injecting medications that inhibit the growth of new blood vessels in the retina, which can help reduce retinal neovascularization and exudation [8]. Anti-VEGF therapy may provide a valuable adjunctive treatment for EXVR2, although its effectiveness and long-term outcomes are still being studied.

Other Treatment Options

In addition to anti-VEGF therapy, other treatment options for EXVR2 may include:

• Laser photocoagulation: This procedure involves using laser light to destroy abnormal blood vessels in the retina [10].
• Topical nonsteroidal anti-inflammatory drugs (NSAIDs): These medications can help reduce inflammation and alleviate symptoms associated with EXVR2 [10].

Important Considerations

It is essential to note that treatment for EXVR2 should be individualized and tailored to each patient's specific needs. A healthcare professional should consult with a specialist, such as an ophthalmologist or retinal specialist, to determine the most effective course of treatment.

X-linked exudative vitreoretinopathy 2 (FEVR) can be challenging to diagnose due to its variable clinical manifestations and similarities with other retinal diseases. The differential diagnosis for FEVR includes:

• Retinopathy of Prematurity (ROP): A condition that affects premature infants, characterized by abnormal blood vessel growth in the retina. Unlike FEVR, ROP is often associated with a history of prematurity and oxygen therapy.
• Norrie Disease: A rare genetic disorder caused by mutations in the NDP gene, leading to retinal degeneration and blindness. While both conditions are inherited, Norrie disease typically presents with more severe retinal degeneration and is not limited to males.
• Coats Disease: A rare eye disorder characterized by abnormal blood vessel growth on the retina, often affecting one eye. Coats disease can be unilateral and sporadic, primarily affecting boys, whereas FEVR tends to affect both eyes and has an X-linked recessive pattern of inheritance.
• Primary Hyperplastic Primary Vitreous (PHPV): A rare congenital condition characterized by abnormal vitreous development, leading to retinal detachment and vision loss. PHPV can be confused with FEVR due to similar clinical manifestations.

To differentiate FEVR from these conditions, clinicians rely on a combination of:

• Family history: X-linked FEVR is inherited in an X-linked recessive pattern, meaning it primarily affects males.
• Clinical examination: Ophthalmological evaluation to assess retinal vasculature development and identify characteristic features such as peripheral avascularity, hyperpermeable blood vessels, and vitreoretinal traction.
• Genetic testing: Molecular analysis of the NDP gene can confirm the diagnosis of X-linked FEVR.

Accurate differential diagnosis is crucial for providing appropriate management and genetic counseling to affected individuals and their families.