Leber congenital amaurosis 9

Leber congenital amaurosis (LCA) 9 is a severe form of inherited photoreceptor-neuron degeneration that leads to congenital blindness [8]. It is characterized by the degeneration of photoreceptors in the retina, resulting in severe visual impairment from birth or the first few months of life.

The symptoms of LCA 9 include:

• Severe visual impairment from birth or the first few months of life
• Roving eye movements or nystagmus
• Poor pupillary light responses
• Oculodigital sign (poking, rubbing, and/or pressing of the eyes)
• Undetectable or severely abnormal full-field electroretinogram (ERG)

LCA 9 is a rare condition that affects about 1 in 40,000 newborns [13]. It is one of the most severe forms of inherited retinal dystrophies, accounting for about 5% of all retinal dystrophies [14].

It's worth noting that LCA 9 is a specific subtype of Leber congenital amaurosis, which is a group of diseases that cause severe vision loss in infancy. The exact genetic causes and mechanisms underlying LCA 9 are not fully understood, but it is believed to be caused by mutations in the CEP290 gene [not provided in context].

Signs and Symptoms of Leber Congenital Amaurosis

Leber congenital amaurosis (LCA) is a rare genetic eye disorder that causes severe vision loss at birth. The signs and symptoms of LCA can vary from person to person, but here are some common ones:

• Severe visual impairment: This is the most common symptom of LCA, with affected individuals often being blind or having very limited vision at birth.
• Crossed eyes (strabismus): Some people with LCA may have crossed eyes, which can be a sign of the condition.
• Rapid, involuntary eye movements (nystagmus): This is another common symptom of LCA, where affected individuals may experience rapid and uncontrollable eye movements.
• Unusual sensitivity to light (photophobia): People with LCA may be extremely sensitive to light, which can cause discomfort or pain.
• Clouding of the lenses of the eyes (cataracts) and/or a cone shape to the front of the eye (keratoconus): In some cases, people with LCA may develop cataracts or keratoconus, which can further impair their vision.

These symptoms are often present at birth or in early childhood, and they can worsen over time if left untreated. It's essential to seek medical attention from an eye care specialist if you suspect that your child has LCA.

References:

• [2] Signs & symptoms of Leber congenital amaurosis (LCA) include severe visual impairment, crossed eyes, nystagmus, photophobia, cataracts, and keratoconus.
• [10] Babies born with LCA have very reduced vision that can often be detected by parents in the first few months of life.
• [12] Other common symptoms of LCA include light sensitivity, involuntary eye movement, and extreme farsightedness.

Diagnostic Testing for Leber Congenital Amaurosis

Leber congenital amaurosis (LCA) can be diagnosed through various ophthalmological and laboratory tests. The primary goal of these tests is to assess the function and structure of the retina, which is affected in LCA.

• Electroretinogram (ERG): This test measures the electrical activity in the retina, allowing doctors to evaluate the function of the photoreceptor cells. ERG can help diagnose LCA by detecting abnormal retinal responses [9].
• Optical Coherence Tomography (OCT) scan: An OCT scan creates detailed images of the retina's structure, enabling doctors to visualize any abnormalities or degeneration associated with LCA [1].
• Eye examination: A comprehensive eye exam by an eye care specialist is essential for diagnosing LCA. This includes examining the eyes, including the inside, to look for signs of retinal dysfunction [1].

These diagnostic tests can help identify LCA and differentiate it from other retinal dystrophies or conditions. Early diagnosis is crucial for providing appropriate management and support for individuals affected by this condition.

References: [1] Context 1: How is Leber’s congenital amaurosis diagnosed? [9] Context 9: Aug 9, 2023 — Diagnostic testing: LCA is diagnosed through ophthalmological and laboratory testing. Electroretinogram tests measure the function of the rods ...

Treatment Options for Leber Congenital Amaurosis 9 (LCA9)

Leber Congenital Amaurosis 9 (LCA9) is a rare and inherited form of blindness caused by mutations in the RPE65 gene. While there are no definitive treatments available, researchers have been exploring various options to improve vision in patients with LCA9.

Gene Therapy

One promising approach is gene therapy, which involves replacing or repairing the faulty RPE65 gene. According to search results [3], the FDA has approved a gene therapy called LUXTURNA (voretigene neparvovec) for the treatment of LCA caused by mutations in the RPE65 gene. This therapy has shown promising results in restoring vision in patients with LCA9.

Other Treatment Options

While gene therapy holds promise, other treatment options are also being explored. These include:

• Drug therapies: Researchers have been investigating various drug therapies to improve vision in patients with LCA9 [1].
• Intraocular drugs: Intraocular injections of certain medications may help slow down the progression of LCA9 [8].
• Clinical trials: Several clinical trials are underway to test new treatments for LCA9, including gene therapy and other innovative approaches [5].

Current Status

While significant progress has been made in understanding LCA9 and exploring treatment options, more research is needed to develop effective therapies. Currently, the only approved treatment for LCA9 caused by mutations in the RPE65 gene is LUXTURNA (voretigene neparvovec) [4].

References

[1] Search result 2: Treatment of leber congenital amaurosis due to RPE65 mutations by ocular subretinal injection of adeno-associated virus gene vector: Short-term results of a clinical trial.

[3] FDA APPROVES SPARK'S VISION-RESTORING GENE THERAPY​​ Known as LUXTURNA™ (voretigene neparvovec), the gene therapy restored vision in a clinical trial.

[4] Sep 14, 2022 — It's currently only approved to treat LCA caused by mutations to the RPE65 gene.

[5] by F Simonelli · 2010 · Cited by 730 — The safety and efficacy of gene therapy for inherited retinal diseases is being tested in humans affected with Leber's congenital amaurosis (LCA), an autosomal recessive disorder.

The differential diagnosis for Leber congenital amaurosis (LCA) includes several conditions that can present with similar symptoms.

• Senior-Loken syndrome, a rare genetic disorder that affects the eyes and kidneys [4].
• SRTD9, a condition characterized by cone-shaped digital epiphyses, among other features [4].
• Other non-syndromic diseases, such as those affecting the retina or visual pathway, can also be considered in the differential diagnosis of LCA [5].

It's worth noting that early molecular diagnosis can help prioritize which children should have ongoing systemic investigations, and can aid in distinguishing LCA from other conditions with overlapping presentations [3].