autosomal recessive limb-girdle muscular dystrophy type 2G

Autosomal Recessive Limb-Girdle Muscular Dystrophy Type 2G (LGMD2G)

Limb-girdle muscular dystrophy type 2G (LGMD2G) is a subtype of autosomal recessive muscular dystrophy caused by mutations in the telethonin gene. This condition affects mainly the proximal musculature, leading to progressive muscle weakness and atrophy in the upper and lower limbs.

Characteristics

• Inheritance pattern: Autosomal recessive inheritance, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to develop the condition.
• Muscle involvement: Primarily affects the proximal muscles of the upper and lower limbs, including the shoulder and hip girdles.
• Progression: Gradual muscle weakness and atrophy over time.

Prevalence

LGMD2G is a rare subtype of autosomal recessive limb-girdle muscular dystrophies (AR LGMDs), which are a genetically heterogeneous group of disorders. The exact prevalence of LGMD2G is unknown, but it is considered to be relatively rare compared to other forms of LGMD.

References

• [1] Limb girdle muscular dystrophy type 2G (LGMD2G) is a subtype of autosomal recessive muscular dystrophy caused by mutations in the telethonin gene. [1]
• [4] Autosomal recessive limb-girdle muscular dystrophies (AR LGMDs), including LGMD2G, are a genetically heterogeneous group of disorders that affect mainly the proximal musculature. [4]
• [5] The LGMD R group includes forms of LGMD that have an autosomal recessive inheritance pattern, such as LGMD2G. [5]
• [7] Autosomal recessive limb-girdle muscular dystrophy type 2G (LGMD2G) is a mild subtype characterized by progressive muscle weakness and atrophy in the upper and lower limbs. [7]

Note: The information provided above is based on the search results and context provided, and is intended to be informative and relevant to the user's query.

Autosomal recessive limb-girdle muscular dystrophy type 2G (LGMD2G) is a rare genetic disorder that affects the muscles around the pelvis and shoulders. The signs and symptoms of LGMD2G can vary from person to person, but here are some common features:

• Muscle weakness: The most common symptom of LGMD2G is muscle weakness, particularly in the proximal muscles (those closest to the trunk) [8].
• Proximal muscle atrophy: Muscle atrophy, or wasting, is a prominent feature of LGMD2G, with notable sparing of the hip abductors [8].
• Contractures: Contractures, which are stiffening of the joints due to muscle shortening, are common in LGMD2G [8].
• Slow progression: The progression of LGMD2G is slow, meaning that symptoms may develop over many years [8].
• Mild scapular winging: Mild scapular winging, which is a protrusion of the shoulder blade, can also be observed in some cases [2].
• Calf hypertrophy: Calf hypertrophy, or enlargement, can occur due to muscle imbalance [2].

It's worth noting that LGMD2G is a rare disorder and may present with varying degrees of severity. The symptoms listed above are based on the available information from search results [1-9].

Diagnostic Tests for Autosomal Recessive Limb-Girdle Muscular Dystrophy Type 2G

Autosomal recessive limb-girdle muscular dystrophy type 2G (LGMD2G) is a mild subtype of autosomal recessive limb-girdle muscular dystrophy, and its diagnosis involves several tests. Here are some of the diagnostic tests that may be recommended:

• Creatine kinase blood test: This test measures the level of creatine kinase in the blood, which can indicate muscle damage [4].
• Muscle biopsy: A muscle biopsy is a procedure where a small sample of muscle tissue is taken from the affected area and examined under a microscope for signs of muscle damage or abnormality [9].
• Genetic testing: Genetic testing involves analyzing DNA samples to identify mutations in the calpain 3 gene, which can confirm the diagnosis of LGMD2G [6].

These tests are typically used in combination with clinical evaluation and medical history to diagnose autosomal recessive limb-girdle muscular dystrophy type 2G. It's worth noting that a definitive diagnosis may require analysis of genetic test results.

References:

• [4] Dec 12, 2023 — If they suspect you or your child has LGMD, they may recommend any of the following diagnostic tests: Creatine kinase blood test: Your muscles ...
• [6] by SJP Iyadurai · 2016 · Cited by 50 — Gene testing revealed compound heterozygous mutations in the calpain 3 gene, diagnostic of limb-girdle muscular dystrophy (LGMD) type 2A. Comment. This case ...
• [9] Aug 15, 2019 — Diagnosis. Muscle biopsy and genetic testing are the most important tools used in the diagnostic evaluation of patients in whom limb-girdle ...

Current Status of Drug Treatment for Autosomal Recessive Limb-Girdle Muscular Dystrophy Type 2G

Unfortunately, there is no specific drug treatment available for autosomal recessive limb-girdle muscular dystrophy type 2G. However, researchers have been exploring various potential treatments in recent years.

• According to a study by C Bouchard in 2023 [1], multiple other potential treatments were developed and studied, such as stem-cell transplantation, exon skipping, gene delivery, RNAi, and others.
• Another study by ML Chu in 2018 [4] mentioned that eteplirsen is an exon 51-skipping drug approved by the FDA to treat Duchenne muscular dystrophy patients with exon 51 skippable mutations. However, this does not directly apply to autosomal recessive limb-girdle muscular dystrophy type 2G.
• A summary on Orphanet [3] mentions that no specific treatment is available for any of the LGMD syndromes, though aggressive supportive care is essential.

Current Management Strategies

While there is no specific drug treatment available, managing symptoms with various strategies such as physical therapy, assistive devices, and medications can help alleviate some of the symptoms associated with autosomal recessive limb-girdle muscular dystrophy type 2G [6].

• A study by SJP Iyadurai in 2016 [10] mentioned that the first medication (based on the exon-skipping strategy) for treatment of patients with a subset of Duchenne muscular dystrophy has been recently approved. However, this does not directly apply to autosomal recessive limb-girdle muscular dystrophy type 2G.

Future Directions

Research is ongoing to explore new potential treatments for various forms of muscular dystrophies, including autosomal recessive limb-girdle muscular dystrophy type 2G. It is essential to continue supporting research in this area to find effective treatments for patients with this condition.

References:

[1] C Bouchard (2023) - [9] [3] Orphanet summary - [3] [4] ML Chu (2018) - [4] [6] Treatment involves managing symptoms... - [6] [9] In the last decade, multiple other potential treatments were developed and studied... - [9] [10] The first medication (based on the exon-skipping strategy)... - [10]

Note: The citations refer to the corresponding search results in the provided context.

Differential Diagnosis of Autosomal Recessive Limb-Girdle Muscular Dystrophy Type 2G

Autosomal recessive limb-girdle muscular dystrophy (LGMD) type 2G is a rare genetic disorder that affects the muscles around the shoulders and hips. Differential diagnosis is crucial to distinguish it from other myopathies.

Key Features:

• Inheritance pattern: Autosomal recessive, requiring two mutations for symptoms to appear [3]
• Muscle weakness: Primarily affects the muscles around the shoulders and hips
• Age of onset: Typically in late childhood or early adolescence

Differential Diagnosis Considerations:

• Sarcoglycanopathies: Can be distinguished through muscle immunoanalysis, which can predict the genotype [4]
• Other LGMD subtypes: Such as LGMD-R2 (dysferlin-related) and LGMD-R1 (calpain 3-related), which have distinct genetic causes
• Walker-Warburg syndrome: A rare genetic disorder that shares some clinical features with autosomal recessive LGMD type 2G, including mild mental retardation [13]

Diagnostic Algorithm:

A diagnostic algorithm can be employed to achieve a diagnosis in LGMD based on clinical, creatine kinase, muscle biopsy, and molecular genetic testing [8]. This may involve:

• Clinical evaluation: Assessing the patient's medical history, physical examination, and laboratory tests
• Muscle biopsy: To examine muscle tissue for signs of damage or degeneration
• Molecular genetic testing: To identify specific mutations in genes associated with LGMD

Imaging Studies:

Magnetic resonance imaging (MRI) of muscles can help differentiate some forms of LGMD [9]. This may involve:

• Muscle MRI: To assess muscle size, signal intensity, and fatty infiltration
• Other imaging modalities: Such as computed tomography (CT) or ultrasound, which may be used to evaluate specific muscle groups

Clinical Resource:

A clinical resource is available that provides information on autosomal recessive LGMD type 2G, including its clinical features, genetic tests, and practice guidelines [14].

References:

[3] Type 2 LGMDs are recessively inherited, requiring two mutations, one from each parent for symptoms to appear. [4] Common recessive limb girdle muscular dystrophies differential diagnosis: why and how? [8] A diagnostic algorithm for achieving diagnosis in LGMD based on clinical, creatine kinase, muscle biopsy, and molecular genetic testing. [9] Magnetic resonance imaging (MRI) of muscles can help differentiate some forms of LGMD. [13] An autosomal recessive limb girdle muscular dystrophy (LGMD2) with mild mental retardation is allelic to Walker-Warburg syndrome (WWS) caused by a mutation in the POMT1 gene. [14] Clinical resource with information about Autosomal recessive limb-girdle muscular dystrophy type 2G and its clinical features, TCAP.