congenital disorder of glycosylation type IIc

Congenital Disorder of Glycosylation Type IIc (CDG2C) Description

Congenital disorder of glycosylation type IIc, also known as CDG-IIc, is a rare and inherited condition that primarily affects the immune, endocrine, and nervous systems. It is caused by an abnormal transport protein that disrupts the normal synthesis of glycans, leading to various clinical manifestations.

Key Features:

• Autosomal Recessive Inheritance: CDG2C is inherited in an autosomal recessive manner, meaning that a person must inherit two copies of the mutated gene (one from each parent) to develop the condition.
• Moderate to Severe Psychomotor Retardation: Individuals with CDG2C often experience moderate to severe psychomotor retardation, which can manifest as delayed or absent speech, cognitive impairment, and motor skill delays.
• Mild to Moderate Hypotonia: Affected individuals may exhibit mild to moderate hypotonia (low muscle tone), which can lead to difficulties with movement and balance.
• Microcephaly: Some individuals with CDG2C may have microcephaly (small head size).
• Epileptic Seizures, Ataxia, Peripheral Neuropathy, and Stroke-like Episodes: Neurological signs and symptoms can include epileptic seizures, ataxia (difficulty with coordination and balance), peripheral neuropathy (nerve damage affecting the limbs), and stroke-like episodes.

**References:

Based on the provided context, here are the signs and symptoms of Congenital Disorder of Glycosylation Type IIc (CDG2C):

• Moderate to severe psychomotor retardation [1]
• Mild cognitive impairment [4]
• Short stature [4]
• Developmental delay, most often affecting speech [4]
• Cognitive impairment ranging from mild to severe [4]
• Neurological signs and symptoms include:
  • Psychomotor retardation [3][5]
  • Hypotonia (muscle weakness) [3][5]
  • Microcephaly (small head size) [3]
  • Epileptic seizures [3][5]
  • Ataxia (lack of muscle coordination) [3][5]
  • Peripheral neuropathy (nerve damage) [3]
  • Stroke-like episodes [3]

These symptoms can begin at infancy or early childhood and are primarily characterized by a compromised immune system, short stature, cognitive impairment, and other neurological issues.

Diagnostic Tests for Congenital Disorder of Glycosylation Type IIc

Congenital disorders of glycosylation (CDGs) are a group of rare genetic disorders that affect the body's ability to properly synthesize and attach sugar molecules to proteins. CDG Type IIc is one such disorder, caused by mutations in the SLC35C1 gene.

Screening Tests While there are no definitive diagnostic tests for CDG Type IIc, screening tests can help identify individuals who may be at risk or have a higher likelihood of having the condition. These tests include:

• Analysis of sugar chains attached to proteins in the blood (serum N-glycans)
• Genetic testing for mutations in the SLC35C1 gene

Genetic Testing Genetic testing is considered the gold standard for diagnosing CDG Type IIc. This involves analyzing the DNA sequence of the SLC35C1 gene to identify any mutations that may be associated with the condition.

Other Diagnostic Tools In addition to genetic testing, other diagnostic tools such as serum N-glycan analysis can also be used to help diagnose CDG Type IIc. However, these tests are not definitive and should be used in conjunction with genetic testing for a confirmed diagnosis.

References

• [5] Screening tests are available for SLC35C1-CDG, but a definitive diagnosis is achieved through genetic testing.
• [8] Clinical Genetic Test offered by Intergen for conditions (1): Leukocyte adhesion deficiency type II; Testing genes (1): SLC35C1 (11p11.2);
• [9] Integrated disease information for Congenital Disorder of Glycosylation, Type Iic including associated genes, mutations, phenotypes, pathways, drugs, ...

**Available Therapies for Congenital Disorder of Glycosylation Type

Differential Diagnosis of Congenital Disorder of Glycosylation Type IIc (CDG2C)

Congenital disorders of glycosylation, formerly known as carbohydrate deficient glycoprotein syndrome, are a group of rare hereditary disorders. CDG2C is an autosomal recessive disorder characterized by moderate to severe psychomotor retardation, mild facial dysmorphism, and other systemic symptoms.

Differential Diagnosis

The differential diagnosis for CDG2C involves considering various other conditions that may present with similar symptoms. These include:

• Mitochondrial disorders
• Immunodeficiency syndromes
• Coagulation disorders
• Other congenital disorders of glycosylation

According to a review by SS Goreta (2012), the differential diagnosis for CDGs is multifaceted, and patients are often suspected to have other disorders. This highlights the importance of comprehensive diagnostic evaluation in cases where CDG2C is suspected.

Clinical Presentation

CDG2C typically presents with symptoms such as:

• Psychomotor retardation
• Mild facial dysmorphism
• Coagulation disorders
• Immunodeficiency

These symptoms can vary in severity and presentation, making differential diagnosis challenging. A thorough medical history, physical examination, and laboratory tests are essential for accurate diagnosis.

References

[4] Congenital disorders of glycosylation (CDG), formerly named carbohydrate deficient glycoprotein syndrome, are rare hereditary disorders. [6] Congenital disorder of glycosylation type IIc (CDG2C) is an autosomal recessive disorder characterized by moderate to severe psychomotor retardation, mild facial dysmorphism, and other systemic symptoms. [7] Differential diagnosis​​ The congenital disorders of glycosylation are multifaceted, and patients are often suspected to have other disorders (eg, mitochondrial disorders). [8] In this review we summarize the current knowledge on the clinical, biochemical and genetic characteristic of distinct CDGs, as well as existing diagnostic and therapeutic approaches.