syndromic X-linked intellectual disability Nascimento type

Syndromic X-linked Intellectual Disability Nascimento Type

The Nascimento type of X-linked syndromic intellectual developmental disorder (MRXSN) is a rare genetic condition characterized by intellectual disability and distinct physical features.

• Intellectual Disability: Individuals with this syndrome typically experience severe intellectual disability, often accompanied by significant speech impairment [1][2].
• Dysmorphic Features: The Nascimento type is marked by dysmorphic features, including:
  • Large head size [6][8]
  • Synophrys (a condition where the eyebrows meet at the bridge of the nose) [7]
  • Other craniofacial abnormalities [4]
• Rare X-linked Intellectual Disability Syndrome: This syndrome is a rare form of X-linked intellectual disability, affecting males more frequently than females due to its location on the X chromosome [3][5].

References:

[1] Context result 2 [2] Context result 5 [3] Context result 3 [4] Context result 4 [5] Context result 9 [6] Context result 6 [7] Context result 7 [8] Context result 8

Characteristics of Syndromic X-linked Intellectual Disability Nascimento Type

The Nascimento type of X-linked syndromic intellectual developmental disorder (MRXSN) is a rare genetic condition characterized by several distinct signs and symptoms. These include:

• Intellectual Disability: Individuals with MRXSN typically exhibit moderate to severe intellectual disability, which can impact their cognitive and adaptive functioning.
• Speech Impairment: Speech development is severely impaired or completely lacking in individuals with MRXSN, making communication a significant challenge.
• Dysmorphic Facial Features: The facial phenotype of individuals with MRXSN is often characterized by a broad face, flat midface, synophrys (a single eyebrow), prominent eyebrows, almond-shaped eyes, low nasal bridge, and other distinctive features.
• Genital Anomalies: Genital anomalies are common in individuals with MRXSN, which can include undescended testes or other reproductive system abnormalities.
• Skin Features: Skin features such as a myxedematous appearance (a condition characterized by thickened skin) may also be present.

Additional Symptoms

In some cases, individuals with MRXSN may experience additional symptoms, including:

• Undeveloped Facial Features: Individuals with UBE2A deficiency syndrome (which is related to MRXSN) may exhibit undeveloped facial features.
• Speech Developmental Delay: Speech development may be delayed or impaired in individuals with MRXSN.

References

1. [3] - The facial phenotype of individuals with MRXSN is characterized by a broad face, flat midface, synophrys and/or prominent eyebrows, almond-shaped eyes, low nasal bridge, ...
2. [7] - Common clinical findings of this syndrome are moderate to severe ID, speech impairment, dysmorphic facial features, genital anomalies and skin features.
3. [8] - X-linked intellectual disability, Nascimento type is a rare X-linked intellectual disability syndrome characterized by intellectual disability (with severe speech impairment), ...
4. [9] - Symptoms of UBE2A deficiency syndrome vary, depending on the degree of mutation present, but can include: Undeveloped facial features; Speech developmental delay; ...

Diagnostic Tests for Syndromic X-linked Intellectual Disability Nascimento Type

The diagnosis of syndromic X-linked intellectual disability Nascimento type involves a combination of clinical evaluation, genetic testing, and other diagnostic tests. Here are some of the key tests used to diagnose this condition:

• Clinical Evaluation: A thorough medical history and physical examination by a qualified healthcare professional is essential in diagnosing syndromic X-linked intellectual disability Nascimento type (MRXSN). The clinical features of MRXSN include dysmorphic features, such as large head size, craniofacial abnormalities, and myxedematous appearance [3][7].
• Genetic Testing: Genetic testing can help confirm the diagnosis of MRXSN. A 106 gene panel that includes assessment of non-coding variants is ideal for patients with a clinical suspicion of X-linked intellectual disability, including MRXSN [4]. This test can identify mutations in the UBE2A gene, which is associated with MRXSN [6][10].
• Other Diagnostic Tests: Other diagnostic tests may be performed to rule out other conditions that may present with similar symptoms. These tests may include imaging studies (e.g., MRI or CT scans) and laboratory tests (e.g., blood tests).

References

[1] Czeschik JC, et al. X-linked intellectual disability type Nascimento: a clinically very distinct entity. 2013.

[2] A rare X-linked intellectual disability syndrome characterized by intellectual disability (with severe speech impairment), a myxedematous appearance, ...

[3] The Nascimento type of X-linked syndromic intellectual developmental disorder (MRXSN) is characterized by dysmorphic features, including large head, ...

[4] A 106 gene panel that includes assessment of non-coding variants. Is ideal for patients with a clinical suspicion of X-linked intellectual disability.

[5] Nascimento type is a rare X-linked intellectual disability syndrome characterized by intellectual disability (with severe speech impairment), a myxedematous appearance, ...

[6] Czeschik JC, et al. X-linked intellectual disability type Nascimento (MIM #300860), caused by mutations in UBE2A (MIM *312180).

[7] The Nascimento type of X-linked syndromic intellectual developmental disorder (MRXSN) is characterized by dysmorphic features, including large head, ...

[8] Integrated disease information for Syndromic X-Linked Intellectual Disability Nascimento Type.

[9] The Nascimento type of X-linked syndromic intellectual developmental disorder (MRXSN) is characterized by dysmorphic features, including large head, ...

[10] Tsurusaki Y, et al. Our findings strongly suggest that UBE2A mutations are causative for X-linked ID type Nascimento.

Treatment Options for Nascimento Type Intellectual Disability

Nascimento type intellectual disability syndrome, a rare X-linked condition, requires specialized treatment approaches. While there is no cure for this condition, various pharmacological and supportive therapies can help manage its symptoms.

• Potassium Supplementation: One of the key components of the treatment protocol involves potassium supplementation to address potential electrolyte imbalances (5).
• Sodium and Spironolactone: Additionally, sodium and spironolactone are used as part of the treatment regimen to manage related conditions such as proteinuria (9).
• Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): NSAIDs may be prescribed to alleviate symptoms associated with inflammation (5, 9).
• Strong Opioids: For refractory patients, strong opioids like methadone and oxycodone are considered third-line treatments, often in conjunction with other therapies (8).

It's essential to note that the treatment protocol for Nascimento type intellectual disability syndrome is still evolving, and more research is needed to develop effective management strategies.

References: * [5] Treatment protocol was potassium supplementation, sodium, spironolactone, and non-steroidal anti-inflammatory drug. Patients who developed proteinuria were ... * [8] by RAA Oliveira · 2020 · Cited by 24 — For refractory patients, strong opioids (methadone and oxycodone), cannabidiol/delta- 9-tetrahydrocannabinol, were classified as third-line of treatment, in ... * [9] by CLP Nascimento · 2014 · Cited by 44 — Treatment protocol was potassium supplementation, sodium, spironolactone, and non-steroidal anti-inflammatory drug. Patients who developed proteinuria were ...

Syndromic X-linked Intellectual Disability Nascimento Type: Differential Diagnosis

The differential diagnosis for syndromic X-linked intellectual disability Nascimento type involves considering various conditions that present with similar clinical features. Based on the search results, here are some key points to consider:

• Clinical Distinctions: Syndromic X-linked intellectual disability Nascimento type is a clinically distinct entity that might be underdiagnosed to date [1][2]. This suggests that it has unique characteristics that differentiate it from other conditions.
• Facial Phenotype: The condition is characterized by a distinctive facial phenotype, including dense eyebrows and eyelashes, synophrys, hypertelorism, upslanted palpebral fissures, and others [3].
• Craniofacial Dysmorphism: X-linked intellectual disability type Nascimento is also associated with craniofacial dysmorphism, which can include features such as a long face, prominent forehead, and others [4][5].

Differential Diagnosis Considerations

When considering the differential diagnosis for syndromic X-linked intellectual disability Nascimento type, it's essential to rule out other conditions that present with similar clinical features. Some of these conditions include:

• Turner-type X-linked Syndromic Intellectual Developmental Disorder (MRXST): This condition is a neurodevelopmental disorder with a highly variable phenotype [6].
• Intellectual Disability and Other Neurodevelopmental Disorders: Intellectual disability, autism spectrum disorder, attention-deficit/hyperactivity disorder, schizophrenia, and bipolar disorders lie on a continuum of neurodevelopmental disorders [7].

Key Points to Consider

In summary, the differential diagnosis for syndromic X-linked intellectual disability Nascimento type involves considering conditions with similar clinical features, such as:

• Unique facial phenotype
• Craniofacial dysmorphism
• Neurodevelopmental disorders

These factors can help guide the diagnostic process and ensure that the correct condition is identified.

References: [1] Czeschik JC (2013) [2] Czeschik JC (2013) [3] Stevenson RE (2019) [4] Czeschik JC (2013) [5] X-linked intellectual disability type Nascimento (MIM #300860) [6] Turner-type X-linked Syndromic Intellectual Developmental Disorder (MRXST) [7] Bogaert E (2023)