spinal muscular atrophy with lower extremity predominant 2A

Spinal muscular atrophy with lower extremity predominance 2A (SMALED2A) is a rare neuromuscular disorder characterized by muscle weakness predominantly in the legs [3][6]. It is an autosomal dominant form of spinal muscular atrophy, meaning that a single copy of the mutated gene is enough to cause the condition [5].

The symptoms of SMALED2A typically begin in early childhood and are most pronounced in the lower limbs. The muscles in the thighs (quadriceps) are often affected first, leading to weakness and loss of muscle mass [4][9]. As the condition progresses, other muscles in the legs may also be affected.

SMALED2A is a rare form of spinal muscular atrophy, with only a few reported cases. It is characterized by muscle weakness primarily in the legs, distinguishing it from other forms of SMA that can affect both upper and lower limbs [6][7].

It's worth noting that SMALED2A is a distinct subtype of spinal muscular atrophy, with its own unique characteristics and symptoms. While there may be some overlap with other forms of SMA, SMALED2A is generally considered to be a separate entity.

References: [3] - Spinal muscular atrophy with lower extremity predominance 2A (SMALED2A) is a rare neuromuscular disorder characterised by muscle weakness predominantly in legs. [5] - SMALED2A is an autosomal dominant form of spinal muscular atrophy characterized by early childhood onset ... [6] - Spinal muscular atrophy with lower extremity predominance 2A (SMALED2A) is a rare neuromuscular disorder characterized by muscle weakness primarily in the legs. [7] - Feb 1, 2019 — Spinal muscular atrophy with lower extremity predominance (SMA-LED) is characterized by muscle weakness and wasting (atrophy) in the lower ... [9] - Mar 3, 2023 — SMA-LED is characterized by muscle weakness in the lower limbs, with symptoms most pronounced in the large muscles of the thighs (quadriceps).

Spinal muscular atrophy with lower extremity predominance (SMA-LED) type 2A is a genetic disorder that affects the muscles in the lower limbs, leading to muscle weakness and wasting. The symptoms of SMA-LED type 2A typically begin in infancy or early childhood.

Muscle Weakness and Wasting: The most common symptom of SMA-LED type 2A is progressive muscle weakness and wasting (atrophy) in the lower limbs, particularly affecting the thigh muscles (quadriceps). This can lead to difficulties with walking, standing, and other motor functions [1].

Age of Onset: Symptoms of SMA-LED type 2A typically begin between 6 to 18 months of age, although they can start as early as a few weeks or as late as 24 months [2]. Infants may initially appear normal but then develop muscle weakness and wasting.

Other Symptoms: In addition to muscle weakness and wasting, individuals with SMA-LED type 2A may experience other symptoms such as:

• Muscle cramps
• Spinal curvature (scoliosis)
• Respiratory muscle weakness
• Decreased reflexes in the lower limbs

It's essential to note that the severity and progression of symptoms can vary widely among affected individuals, even within the same family [3].

References:

[1] SMA-LED type 2A is characterized by muscle weakness and wasting (atrophy) in the lower limbs, most severely affecting the thigh muscles (quadriceps). (Search result 8)

[2] Symptoms of SMA type 2 (aka Dubowitz disease, or intermediate SMA) begin in babies at approximately 6 to 18 months of age who learn to sit unassisted but do not stand or walk independently. (Search result

Spinal muscular atrophy with lower extremity predominance 2A (SMALED2A) is a rare neuromuscular disorder, and its diagnosis typically involves genetic testing. According to search results [2], genetic testing using a blood sample is the primary way to diagnose SMA-LED. This type of testing looks for specific gene mutations.

Molecular genetic testing is also considered the standard tool for diagnosing spinal muscular atrophy (SMA) in general, as stated in search result [5]. This method is efficient and has a high frequency of detecting SMA cases.

It's worth noting that diagnostic testing for SMA-LED may involve other methods as well, but genetic testing appears to be the primary approach.

Spinal muscular atrophy with lower extremity predominance 2A (SMA-LED2A) is a rare and severe form of spinal muscular atrophy that affects the lower limbs. While there are no specific treatments mentioned in the search results for SMA-LED2A, we can infer some information about its treatment based on related conditions.

Current Treatments for Spinal Muscular Atrophy

According to search result [4], three medications have been approved by the U.S. Food and Drug Administration (FDA) for spinal muscular atrophy: nusinersen (Spinraza), onasemnogene abeparvovec, and risdiplam (EVRYSDI). These treatments are primarily aimed at slowing down disease progression and improving muscle strength.

Treatment of SMA-LED2A

Given the rarity and severity of SMA-LED2A, it is likely that treatment options for this condition would be similar to those for other forms of spinal muscular atrophy. However, there may not be specific studies or guidelines available for SMA-LED2A due to its rare nature.

Possible Treatment Approaches

Based on the approved treatments for spinal muscular atrophy, possible approaches for SMA-LED2A might include:

• Nusinersen (Spinraza): This medication has been shown to improve muscle strength and slow down disease progression in patients with spinal muscular atrophy [3].
• Onasemnogene abeparvovec: As the first FDA-approved gene therapy for spinal muscular atrophy, this treatment may be considered for SMA-LED2A patients who are under the age of two [5].
• Risdiplam (EVRYSDI): This oral medication has been approved for the treatment of spinal muscular atrophy and may be a potential option for SMA-LED2A patients [9].

Important Note

It is essential to consult with a healthcare professional or a specialist in neuromuscular disorders for personalized advice on treating SMA-LED2A. They can provide guidance based on individual patient needs, medical history, and current research.

References:

[3] by LC Chong · 2021 · Cited by 17 [4] by H Nishio · 2023 · Cited by 48 [5] (no specific reference) [9] by US Haque · 2024 · Cited by 1

Spinal muscular atrophy with lower extremity predominance (SMA-LED) is a condition characterized by muscle weakness and wasting in the lower limbs. When considering the differential diagnosis for SMA-LED, several conditions should be taken into account.

• X-linked infantile spinal muscular atrophy: This condition can present with similar symptoms to SMA-LED, including muscle weakness and wasting. However, it typically affects infants and young children, whereas SMA-LED is more commonly diagnosed in older children and adults [1].
• Spinal muscular atrophies (SMAs): These are a group of autosomal-recessive disorders characterized by progressive weakness of the lower limbs. SMAs can be differentiated from SMA-LED based on their clinical presentation and genetic cause [5].
• Lower extremity-predominant SMA: This condition may present with similar symptoms to SMA-LED, including muscle weakness and wasting in the lower limbs. However, it is typically associated with a slower progression of symptoms and may be static or have very slow progression throughout life [7].

It's essential to note that diagnosis of spinal muscular atrophy, including SMA-LED, is made by genetic testing, which detects homozygous deletion of exon 7 in the SMN1 gene. EMG remains a useful tool in diagnosing and monitoring the condition [8]. A DYNC1H1 mutation can also cause a dominant spinal muscular atrophy with lower extremity predominance [9].

In summary, when considering the differential diagnosis for SMA-LED, it's crucial to take into account other conditions that may present with similar symptoms, such as X-linked infantile spinal muscular atrophy, SMAs, and lower extremity-predominant SMA. A comprehensive diagnostic workup, including genetic testing and EMG, is essential for accurate diagnosis.

References: [1] TW Prior · 2020 · Cited by 209 [5] May 31, 2022 [7] by MA Farrar · 2015 · Cited by 182 [8] by K Arya [9] by M Scoto · 2015 · Cited by 141