megalencephalic leukoencephalopathy with subcortical cysts 2B

Megalencephalic leukoencephalopathy with subcortical cysts type 2B (MLC2B) is a rare inherited disorder characterized by infantile-onset of macrocephaly and mildly delayed motor development [7]. It is one of the two phenotypes of megalencephalic leukoencephalopathy with subcortical cysts, the other being classic MLC.

Individuals with MLC2B typically present with an enlarged brain (megalencephaly) that becomes apparent at birth or within the first year of life [14]. They may also experience mildly delayed motor development and have a relatively normal cognitive function compared to those with classic MLC.

It's worth noting that MLC2B is caused by genetic changes in the HEPACAM gene, which is inherited in an autosomal recessive manner [13]. This means that both parents must carry a mutated copy of the gene for their child to be affected.

Early Signs and Symptoms

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) typically presents in early childhood, with the following signs and symptoms:

• Macrocephaly: An enlarged brain that is evident at birth or within the first year of life [1].
• Delayed walking: Children with MLC often experience delayed walking, which may be unstable, leading to frequent falls [2].
• Mild motor developmental delay: Infants and young children with MLC may exhibit mild delays in motor development [3].

Later-Onset Symptoms

As the condition progresses, individuals with MLC may experience:

• Motor problems: Deterioration of motor functions, including ataxia (loss of coordination) and spasticity (increased muscle tone) [5].
• Epilepsy: Seizures are a common symptom in individuals with MLC [5].
• Slow cognitive decline: Gradual decline in cognitive function over time [7].

Other Symptoms

In addition to the above symptoms, individuals with MLC may also experience:

• Developmental delay: Mild delays in developmental milestones, such as speech and language development [8].
• Movement and coordination difficulties: Children with MLC may have difficulty with movement and coordination, leading to falls and other accidents [8].

It is essential to note that the symptoms of MLC can vary in severity and progression from one individual to another.

Diagnostic Tests for Megalencephalic Leukoencephalopathy with Subcortical Cysts (MLC)

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) can be diagnosed through a combination of clinical evaluation, imaging studies, and genetic testing.

• Brain MRI: A brain MRI scan is the primary diagnostic tool for MLC. It shows a distinct pattern of abnormal and swollen white matter of the brain and the presence of cysts (cavities filled with fluid) [4].
• Genetic Testing: Genetic testing can confirm the diagnosis of MLC by identifying mutations in the DCAF1 gene or other genes associated with the condition [6]. However, these tests may also be inconclusive because other genes that have not been identified yet may also be involved.
• Clinical Evaluation: A clinical evaluation is essential to diagnose MLC. It involves assessing the individual's medical history, physical examination, and laboratory tests to rule out other conditions that may present with similar symptoms [3].

Diagnostic Criteria

The diagnosis of MLC is based on diagnostic criteria, including brain MRI findings, macrocephaly (large head size), and clinical evaluation. A negative test result does not rule out a diagnosis of MLC since a mutation may not be detected by genetic testing [6].

Other Diagnostic Tests

Other diagnostic tests that may be used to support the diagnosis of MLC include:

• Macro/megalencephaly: This is a condition characterized by an abnormally large head size, which is often associated with MLC.
• Cystic degeneration of white matter: This refers to the presence of cysts or cavities in the white matter of the brain, which is a hallmark feature of MLC.

References

[1] Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is characterized by two phenotypes: classic

Management and Treatment Options

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a progressive condition that affects brain development and function. While there is no definitive therapy for MLC, various treatments can help manage its symptoms.

• Symptom management: Treatments address the symptoms of the disease, such as medications to control seizures and slow cognitive decline [8].
• Condition management information: Although there is currently no specific treatment for this leukodystrophy, condition management information may be useful in managing your symptoms [5].

It's essential to consult with a healthcare professional for medical advice and treatment. They can help determine the best course of action based on individual needs.

Current Treatment Options

As of now, there are no treatments or cures available for the underlying cause of MLC. However, various medications may be prescribed to manage symptoms such as seizures and slow cognitive decline [8].

• Medications: Medications can help control seizures and slow cognitive decline, but they do not address the underlying cause of the disease [8].
• No treatment is available: Unfortunately, there is no treatment or cure for the underlying cause of MLC. Treatments only address the symptoms of the disease [9].

Consult a Healthcare Professional

It's crucial to consult with a healthcare professional for medical advice and treatment. They can provide personalized guidance on managing symptoms and addressing individual needs.

References: [5] - Although there is currently no specific treatment for this leukodystrophy, there is condition management information that may be useful for you in managing your symptoms. [8] - Treatments address the symptoms of the disease, such as medications to control seizures and slow cognitive decline. [9] - With delayed onset, patients typically experience motor problems, epilepsy and slow cognitive decline. No treatment is available.

The differential diagnosis for megalencephalic leukoencephalopathy with subcortical cysts 2B (MLC2B) includes several conditions that present similar symptoms. According to the medical literature, these conditions include:

• Canavan disease: This is a rare genetic disorder that affects the brain and spinal cord, leading to progressive damage and degeneration of the white matter in the brain. Like MLC2B, Canavan disease can cause macrocephaly (increased head size), ataxia, spasticity, seizures, and cognitive decline [8].
• Alexander disease: This is a rare genetic disorder that affects the brain, leading to progressive damage and degeneration of the white matter in the brain. Like MLC2B, Alexander disease can cause macrocephaly, ataxia, spasticity, seizures, and cognitive decline [8].
• Infantile-onset GM2 gangliosidosis: This is a rare genetic disorder that affects the brain, leading to progressive damage and degeneration of the white matter in the brain. Like MLC2B, infantile-onset GM2 gangliosidosis can cause macrocephaly, ataxia, spasticity, seizures, and cognitive decline [8].

These conditions are often considered in the differential diagnosis for MLC2B because they share similar symptoms and characteristics. However, it's worth noting that each condition has its own unique features and diagnostic criteria.

References:

• [8] Jan 16, 2023 — The differential diagnosis includes Canavan disease, alexander disease, and infantile-onset GM2 gangliosidosis. Canavan disease shows similar symptoms to MLC2B.
• [9] Symptoms include poor ambulation, falls, ataxia, spasticity, seizures, and cognitive decline. Brain imaging shows abnormal white matter and subcortical cysts.