Behr syndrome

Behr syndrome, also known as early-onset optic atrophy with spinocerebellar degeneration, is a rare genetic disorder characterized by the association of early-onset optic atrophy with neurological features.

Key Features:

• Early-onset optic atrophy [1][2]
• Spinocerebellar degeneration resulting in ataxia [9]
• Pyramidal signs [9]
• Peripheral neuropathy [9]
• Developmental delay [1]

Genetic Basis: Behr syndrome is caused by genetic changes in the OPA1 gene, which is inherited in an autosomal recessive manner. This means that individuals with Behr syndrome have mutations in both copies of the OPA1 gene, one inherited from each parent.

Other Signs and Symptoms:

• Ataxia [7][8]
• Spasticity [7][8]
• Intellectual disability [7][8]
• Visual loss at an early age due to progressive degeneration of the optic nerve [14]

Important Note: Case descriptions reported in the literature often cannot be accurately assigned to a specific condition without genotyping. Therefore, histological reports of retinal ganglion cell loss and histological alterations in the brain may or may not be a part of Behr syndrome.

References:

[1] Context result 1 [2] Context result 1 [3] Context result 4 [7] Context result 7 [8] Context result 8 [9] Context result 9 [14] Context result 14

Behr syndrome is characterized by a combination of early-onset optic atrophy and neurological features, including:

• Optic Atrophy: Early-onset optic atrophy is the first symptom in most patients, leading to vision loss and blindness [1].
• Ataxia: Patients with Behr syndrome often experience unsteadiness, gait difficulties, and balance problems due to spinocerebellar degeneration [3][7].
• Spasticity: Spastic paraparesis, distal weakness, and motor neuropathy are common neurological symptoms in patients with Behr syndrome [5].
• Intellectual Disability: Many patients have cognitive impairments, including mental retardation [4][8].
• Sensory Loss: Patients may experience sensory deficits, such as numbness or tingling sensations in the hands and feet [6][7].
• Cognitive Deficits: Cognitive impairments are a common feature of Behr syndrome, affecting memory, attention, and other cognitive functions [5][6].
• Other Neurological Symptoms: A wide range of non-specific neurologic signs and symptoms may be present, including myoclonic epilepsy, ataxia, spastic gait, axonal sensorimotor neuropathy, and posterior column dysfunction [8].

These symptoms can vary in severity and progression among patients with Behr syndrome.

Behr syndrome, also known as early-onset optic atrophy, is a rare genetic disorder that affects the optic nerves and can lead to various neurological symptoms. Diagnostic tests for Behr syndrome are crucial in confirming the diagnosis and ruling out other conditions.

Clinical Evaluation

A thorough clinical evaluation is essential in diagnosing Behr syndrome. This includes a complete neurological examination, which may reveal signs of ataxia, spasticity, intellectual disability, and posterior column sensory loss [11]. A detailed medical history, including family history, can also provide valuable information.

Genetic Testing

Genetic testing plays a significant role in diagnosing Behr syndrome. MLPA (Multiplex Ligation-dependent Probe Amplification) has been shown to be highly sensitive for detecting deletion and duplication variants in the affected area [2, 9]. This test can help identify mutations in the OPA1 gene, which is associated with early-onset atrophy called Behr optic atrophy [14].

Neuroimaging Studies

Neuroimaging studies, such as MRI (Magnetic Resonance Imaging) and CT scans, may be performed to rule out other conditions that can cause similar symptoms. These studies can help identify changes in the brain and spinal cord associated with Behr syndrome.

Other Diagnostic Tests

Other diagnostic tests that may be used to diagnose Behr syndrome include:

• Spinal tap (lumbar puncture) [6]
• Electromyography [6]

It's essential to note that a combination of clinical evaluation, genetic testing, and neuroimaging studies is often necessary to confirm the diagnosis of Behr syndrome.

References: [2] - Search result 5 [9] - Search result 4 [11] - Search result 11 [14] - Search result 14

Behr syndrome, also known as optic atrophy with ataxia and spasticity, is a rare genetic disorder that affects the nervous system. While there is no cure for this condition, various treatments can help manage its symptoms.

Treatment Options

According to medical experts [5], Behr syndrome shares many features with other disorders, such as Leber's hereditary optic neuropathy (LHON). Treatment for Behr syndrome typically involves a multidisciplinary approach, including:

• Antiepileptic treatment: Some patients may experience seizures, and antiepileptic medications can help manage these symptoms [7].
• Anxiolysis: Anxiety management techniques may be helpful in reducing stress and anxiety associated with the condition [7].
• Idebenone treatment: Research suggests that idebenone, a medication used to treat LHON, may also be beneficial for patients with Behr syndrome. Experts recommend starting idebenone treatment at 900 mg/day as soon as possible after visual loss onset [8].

Other Considerations

It's essential to note that each patient's experience with Behr syndrome is unique, and treatment plans should be tailored to individual needs. Additionally, patients may require ongoing medical care to manage symptoms and prevent complications.

References:

[5] Behr syndrome was first described by Carl Behr in 1909 [6]. [7] In particular, a history of current medical treatment and efficacy for seizures should be obtained [7]. [8] Experts agreed that idebenone treatment at 900 mg/day should start as soon as possible in the acute stage (within a year from visual loss onset) [8].

Behr syndrome, also known as early-onset optic atrophy combined with various neurological symptoms, requires a comprehensive differential diagnosis to rule out other conditions that may present similar signs and symptoms.

Common causes of optic neuropathies:

• Compressive optic neuropathy
• Inflammatory optic neuropathy (e.g., optic neuritis)
• Ischemic optic neuropathy
• Toxic optic neuropathy (e.g., due to exposure to certain chemicals or medications)
• Metabolic optic neuropathy (e.g., due to diabetes, thyroid disorders, or other metabolic conditions)

Other hereditary conditions:

• Inherited peripheral neuropathies (e.g., Charcot-Marie-Tooth disease)
• Spastic paraplegias
• Ataxias (e.g., Friedreich's ataxia)
• Mitochondrial respiratory chain deficiencies

Genetic mutations associated with Behr syndrome:

• Mutations in the OPA1, OPA3, or C12orf65 genes have been reported to cause pure optic atrophy or optic atrophy complicated by movement disorder.

Clinical conditions that may mimic Behr syndrome:

• Other hereditary conditions, such as inherited peripheral neuropathies, spastic paraplegias, and ataxias
• Mitochondrial respiratory chain deficiencies
• Compressive, inflammatory, ischemic, toxic, or metabolic causes of optic neuropathy

To accurately diagnose Behr syndrome, it is essential to consider these differential diagnoses and rule out other conditions that may present similar symptoms. A comprehensive diagnostic workup, including genetic testing, should be performed to confirm the diagnosis.

References:

• [8] Differential diagnosis includes all the common causes of optic neuropathies: compressive, inflammatory, ischemic, toxic and metabolic causes.
• [9] Other hereditary conditions: inherited peripheral neuropathies (e.g., Charcot-Marie-Tooth disease), spastic paraplegias, ataxias (e.g., Friedreich's ataxia)
• [11] Genetic mutations associated with Behr syndrome: OPA1, OPA3, or C12orf65 genes.