autosomal recessive progressive external ophthalmoplegia with mitochondrial DNA deletions 3

Autosomal recessive progressive external ophthalmoplegia (PEOB) with mitochondrial DNA deletions is a rare genetic disorder characterized by multiple mitochondrial DNA deletions in skeletal muscle. This condition typically presents in adulthood and is associated with weakness of the external eye muscles, exercise intolerance, and other systemic features.

The clinical features of PEOB3 include:

• Adult onset of progressive external ophthalmoplegia
• Exercise intolerance
• Muscle weakness, particularly affecting the proximal limbs and neck
• Signs and symptoms of spinocerebellar ataxia, such as impaired gait and dysarthria

This condition is inherited in an autosomal recessive pattern, meaning that a person must inherit two copies of the mutated gene (one from each parent) to develop the disorder. The severity of PEOB3 can vary among affected individuals.

It's worth noting that PEOB3 is one of several subtypes of progressive external ophthalmoplegia with mitochondrial DNA deletions, and the specific features and inheritance pattern may differ depending on the underlying genetic mutation [11][12].

References: [11] Ronchi et al. (2012) - "Autosomal recessive progressive external ophthalmoplegia with mitochondrial DNA deletions-4 (PEOB4)" [12] Luoma et al. (2003) - "Familial and sporadic progressive external ophthalmoplegia: a review of the literature"

Autosomal recessive progressive external ophthalmoplegia with mitochondrial DNA deletions, also known as PEOB2, is a mitochondrial disorder characterized by several signs and symptoms. These include:

• Adult onset of progressive external ophthalmoplegia: This refers to the gradual weakening of the muscles that control eye movement, leading to impaired eye movements.
• Exercise intolerance: Individuals with PEOB2 may experience fatigue or shortness of breath during physical activity due to muscle weakness.
• Muscle weakness: Progressive muscle weakness is a hallmark symptom of PEOB2, affecting various muscle groups.
• Signs and symptoms of spinocerebellar ataxia: Some individuals with PEOB2 may exhibit impaired gait (walking) and dysarthria (speech difficulties), which are characteristic features of spinocerebellar ataxia.

These symptoms can vary in severity and may be accompanied by other signs, such as cataracts, hearing loss, sensory axonal neuropathy, depression, hypogonadism, and parkinsonism. It's essential to note that the specific combination and severity of symptoms can differ among individuals with PEOB2.

References:

• [12] describes adult onset of progressive external ophthalmoplegia, exercise intolerance, muscle weakness, and signs and symptoms of spinocerebellar ataxia in patients with PEOB2.
• [8] mentions exercise intolerance, muscle weakness, and signs and symptoms of spinocerebellar ataxia, such as impaired gait and dysarthria, in PEOB2 patients.

Based on the search results, here are some diagnostic tests for autosomal recessive progressive external ophthalmoplegia with mitochondrial DNA deletions:

• Molecular Genetics - Deletion/duplication analysis: Multiplex Ligation-dependent Probe Amplification (MLPA) [1]
• Southern blot analysis and PCR showed multiple mtDNA deletions in skeletal muscle of all affected family members, but not in lymphocytes or fibroblasts. The mtDNA deletions appeared to increase with time and correlated with disease severity [15]

It's worth noting that genetic sequencing is the gold standard for diagnosing mitochondrial encephalomyopathies, preceded by non-invasive tests such as fibroblast growth factor-21 and growth differentiation factor-15 [11]. However, it's not clear if these tests are specifically used for autosomal recessive progressive external ophthalmoplegia with mitochondrial DNA deletions.

Additionally, clinical genetic tests are available for conditions related to this disorder, including Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant 1 [9].

It's also mentioned that experts providing highly subspecialized diagnostic and interventional radiology care may be able to provide further guidance on diagnostic testing for this condition [10].

Based on the search results, it appears that there are limited treatment options available for autosomal recessive progressive external ophthalmoplegia with mitochondrial DNA deletions-3 (PEOB3).

Current Treatments:

• There is no specific drug treatment mentioned in the search results for PEOB3.
• However, some general treatments for progressive external ophthalmoplegia (PEO) are mentioned, such as:
  • Surgery or special glasses to correct drooping eyelids [7]
  • Physical and occupational therapy to address limb weakness [7]

Experimental Treatments:

• Some research studies have investigated the use of various drugs to treat mitochondrial diseases, including PEO.
• However, these studies are not specifically focused on PEOB3, and more research is needed to determine their effectiveness.

Future Directions:

• Further research is necessary to identify effective treatments for PEOB3.
• Investigating new therapeutic approaches, such as gene therapy or pharmacological interventions targeting mitochondrial function, may hold promise for improving outcomes in patients with this condition.

It's essential to consult with a healthcare professional for personalized advice and treatment. They can provide more information on the current state of research and potential treatment options.

References:

[7] - Physical and occupational therapy to address limb weakness [7] - Surgery or special glasses to correct drooping eyelids

Autosomal recessive progressive external ophthalmoplegia (arPEO) with mitochondrial DNA deletions is a rare genetic disorder characterized by weakness and degeneration of the eye muscles, leading to ptosis (drooping eyelids) and impaired eye movements. The condition typically presents in childhood or adolescence.

Key Features:

• Bilateral symmetrical progressive ptosis
• Reduced ocular motility
• Proximal muscle weakness
• Bulbar dysfunction

Differential Diagnosis:

The differential diagnosis for arPEO with mitochondrial DNA deletions includes other conditions that present with similar symptoms, such as:

• Kearns-Sayre syndrome (KSS)
• Mitochondrial neurogastrointestinal encephalopathy (MNGIE)
• RRM2B autosomal recessive progressive external ophthalmoplegia (arPEO)

Causes:

The condition is caused by homozygous or compound heterozygous mutations in the mitochondrial DNA, leading to deletions and dysfunction of the mitochondrial genome.

References:

• [4] Autosomal dominant progressive external ophthalmoplegia (adPEO) is a mitochondrial disease characterized by accumulation of multiple large deletions of mtDNA...
• [13] RRM2B autosomal recessive progressive external ophthalmoplegia (arPEO), a typically childhood-onset predominantly myopathic phenotype of PEO, ptosis, proximal muscle weakness, and bulbar dysfunction.
• [15] Chronic progressive external ophthalmoplegia (CPEO) is the most common manifestation of mitochondrial diseases and is characterized by bilateral symmetrical progressive ptosis and reduced ocular motility.