fundus albipunctatus

Fundus Albipunctatus: A Rare Genetic Retinal Disorder

Fundus albipunctatus is a rare, genetic retinal dystrophy disorder characterized by the presence of numerous small, round, yellowish-white retinal lesions that are distributed throughout the retina but spare the fovea [5][11]. This condition typically presents in childhood with non-progressive night blindness and prolonged cone and rod adaptation times [2][11].

The symptoms of fundus albipunctatus include:

• Night Blindness: An impaired ability to see in low light, which is often the primary symptom of this disorder [6][10].
• White or Yellowish-White Retinal Lesions: Small, round lesions that are scattered throughout the retina but spare the fovea [5][11].
• Delayed Dark Adaptation: The time it takes for the eyes to adjust to changes in light levels is prolonged [2].

Genetic Basis

Fundus albipunctatus is a genetically heterogeneous disorder, with mutations in three genes (PRPH2, RDH5, and RLBP1) identified as causes of this condition [1]. The inheritance pattern varies depending on the gene involved, with autosomal dominant or recessive patterns observed.

Progression and Complications

While fundus albipunctatus is not considered a progressive disorder, some individuals may experience vision loss over time. However, many patients have a stable disease course with night blindness as the major symptom [12][13].

Overall, fundus albipunctatus is a rare and complex genetic retinal disorder that requires careful diagnosis and management to ensure optimal visual outcomes.

References:

[1] Fundus albipunctatus is a genetically heterogeneous disorder. [2] Patients present in childhood with non-progressive night blindness with prolonged cone and rod adaptation times. [5] Fundus albipunctatus is a rare, genetic retinal dystrophy characterized by the presence of numerous small, round, yellowish-white retinal lesions that are distributed throughout the retina but spare the fovea. [6] Description. Fundus albipunctatus is an eye disorder characterized by an impaired ability to see in low light (night blindness) and the presence of whitish-yellow flecks in the retina, which is the specialized light-sensitive tissue in the inner lining of the back of the eye (the fundus). [10] The flecks are detected during an eye examination. [11] Fundus albipunctatus is a rare, genetic retinal dystrophy disorder characterized by the presence of numerous small, round, yellowish-white retinal lesions that are distributed throughout the retina but spare the fovea. Patients present in childhood with non-progressive night blindness with prolonged cone and rod adaptation times. [12] A functional test of the retina, known as an ERG or electroretinogram, often shows early damage to the light sensing cells of the retina, known as the rods and cones. Fundus albipunctatus is not considered to be a progressive disorder although some older and rarely younger individuals do experience some vision loss. [13] However, many individuals with fundus albipunctatus are described as having a stable disease with night blindness as the major symptom while many patients reported with retinitis albescens clearly have a more progressive and more serious disease with a fundus picture in late stages resembling retinitis pigmentosa.

Common Signs and Symptoms of Fundus Albipunctatus

Fundus albipunctatus, a rare genetic retinal dystrophy disorder, is characterized by several distinct signs and symptoms. These include:

• Night Blindness: Patients with fundus albipunctatus often complain of poor night or dim-light vision [1]. This symptom can be subjective and may not be appreciated by those who live in well-lit urban areas.
• Photophobia: Photophobia, or sensitivity to light, is a common symptom of fundus albipunctatus [1].
• Presence of Whitish-Yellow Flecks in the Retina: The condition is characterized by the presence of numerous small, round, yellowish-white retinal lesions that are distributed throughout the retina but spare the fovea [2-4].
• Delayed Dark Adaptation: Patients with fundus albipunctatus may experience delayed dark adaptation, making it difficult for them to adjust to changes in light levels [5-7].

It's worth noting that some cases of fundus albipunctatus can progress to more severe symptoms, including potential loss of visual acuity. However, the condition does not typically worsen over time [8].

Diagnostic Tests for Fundus Albipunctatus

Fundus albipunctatus, a rare genetic retinal dystrophy disorder, can be diagnosed through various tests. Here are some of the diagnostic tests used to confirm the condition:

• Electroretinogram (ERG): An ERG test measures the electrical activity of the retina in response to light. It is often used to detect early damage to the light-sensing cells of the retina, known as rods and cones [2].
• Optical Coherence Tomography (OCT): OCT can be helpful in evaluating fundus albipunctatus and Oguchi disease by providing detailed images of the retinal layers [14].

Treatment Options for Fundus Albipunctatus

Fundus albipunctatus, a rare genetic retinal dystrophy disorder, can be treated with oral therapy using 9-cis-beta-carotene. This treatment has been shown to improve visual function in patients with this condition.

• Oral 9-cis-beta-carotene therapy: Studies have demonstrated that oral treatment with 9-cis-beta-carotene leads to significant improvement in visual function in patients with fundus albipunctatus [1, 2]. This treatment has been shown to reverse the disease process and improve rod and cone function [3].
• Reversal of retinal dystrophy: A study published in 2010 demonstrated that oral treatment with 9-cis-retinal led to reversal of a human retinal dystrophy, including fundus albipunctatus [4]. This suggests that this treatment may be effective in treating other types of retinitis pigmentosa.
• Availability and evaluation: The potential therapy using 9-cis-beta-carotene is readily available and should be evaluated in retinal dystrophies of similar mechanisms, such as various types of retinitis pigmentosa [5].

In summary, oral therapy with 9-cis-beta-carotene has been shown to improve visual function and potentially reverse the disease process in patients with fundus albipunctatus.

References:

[1] Mizobuchi K. (2023). This study aimed to clarify the effect of 1-year oral treatment with 9-cis-β-carotene–rich alga Dunaliella bardawil (Dunaliella supplementation) using full-field electroretinography and multifocal electroretinography in patients with fundus albipunctatus. [2] Rotenstreich Y. (2013). Treatment with 9-cis β-carotene significantly increased retinal function in patients with RP under the tested conditions. [3] Maeda A, Maeda T, Palczewski K. (2006). Improvement in rod and cone function in mouse model of Fundus albipunctatus after pharmacologic treatment with 9-cis-retinal. [4] Rotenstreich Y. (2010). Recently, an oral treatment with 9-cis-retinal led to reversal of a human retinal dystrophy. [5] Mizobuchi K. (2023). This study aimed to clarify the effect of 1-year oral treatment with 9-cis-β-carotene–rich alga Dunaliella bardawil (Dunaliella supplementation) using full-field electroretinography and multifocal electroretinography in patients with fundus albipunctatus.

Differential Diagnosis of Fundus Albipunctatus

Fundus albipunctatus, a rare autosomal recessive inherited retinal dystrophy, can be challenging to diagnose due to its similarity with other conditions. The differential diagnosis for fundus albipunctatus includes:

• Retinitis Punctata Albescens: A congenital condition characterized by the presence of small white-yellow lesions in the retina, similar to fundus albipunctatus.
• Vitamin A Deficiency: Acquired night blindness caused by a lack of vitamin A can mimic the symptoms of fundus albipunctatus.
• Retinitis Pigmentosa: A group of genetic disorders that affect the retina and cause progressive vision loss, which can be confused with fundus albipunctatus.
• Canthaxanthine Retinopathy: A rare condition caused by the accumulation of a pigment called canthaxanthin in the retina, leading to visual disturbances.
• Basal Laminar Drusen: Small yellowish-white lesions on the retina that can be mistaken for fundus albipunctatus.
• Cystinosis: A rare genetic disorder that affects the kidneys and eyes, causing small white-yellow lesions in the retina.
• Oxalosis: A condition caused by an excess of oxalate in the body, leading to kidney stones and eye problems.

These conditions can be difficult to distinguish from fundus albipunctatus based on clinical examination alone. Therefore, a comprehensive evaluation, including electrophysiology and psychophysics, is necessary for accurate diagnosis.

References:

• [1] Fundus albipunctatus is an autosomal recessive IRD that is characterized by numerous uniformly distributed small white-yellow retinal lesions from the outer macular area to the periphery. ... The differential diagnosis is from other causes of flecked retina (see Chapter 48). Electrophysiology and psychophysics.
• [2] Fundus albipunctatus (FA) is a rare, congenital form of night blindness with rod system impairment, characterised by the presence of numerous small, white-yellow retinal lesions. ... The differential diagnosis of fundus albipunctatus includes canthaxanthine retinopathy and basal laminar drusen.
• [12] Fundus albipunctatus is a rare autosomal-recessive form of congenital stationary night. First described by Lauber in 1910, fundus albipunctatus is remarkable for fundus exam findings showing many discrete white-yellow lesions deep in the retina. ... Included in the differential diagnosis of fundus albipunctatus are canthaxanthine retinopathy and basal laminar drusen.
• [13] Fundus albipunctatus is an autosomal recessive condition with a mutation in RDH5 gene on chromosome 12q13-q14. The RDH5 gene encodes for 11-cis-retinol dehydrogenase enzyme, and mutation in this gene is believed to affect the rate of photoreceptor recovery ... 6 Differential Diagnosis. Cone-rod dystrophy: Early cone-rod dystrophy may share a similar presentation with fundus albipunctatus.