Clinical Experience of Timing Treatment in Newborns with Spinal Muscular Atrophy: A Call for Standardized Screening...

Area of Science:

• Neurology
• Genetics
• Pediatrics

Background:

• Spinal muscular atrophy (SMA) is a rare, progressive neuromuscular disorder impacting muscle strength, often severe in early infancy.
• Early diagnosis and treatment initiation are crucial for managing SMA, with disease-modifying therapies showing significant benefits.
• Newborn screening (NBS) is essential for identifying infants with SMA before symptom onset, allowing for prompt therapeutic intervention.

Purpose of the Study:

• To evaluate the effectiveness of a newborn screening program for spinal muscular atrophy (SMA) in the Campania region, Italy.
• To assess the motor function outcomes in infants treated for SMA following early detection through newborn screening.
• To emphasize the importance of timely diagnosis and intervention for improving motor development in infants with SMA.

Main Methods:

• A newborn screening program identified infants for SMA between April 2023 and October 2024.
• SMN1 gene deletion and SMN2 copy number were analyzed using RT-PCR and multiplex ligation-dependent probe amplification.
• Motor function was assessed using CHOP-INTEND and Bayley III scales post-treatment.

Main Results:

• Out of 62,801 infants screened, thirteen tested positive for SMA (11 female, 2 male).
• SMN2 copy numbers varied: eight patients had two copies, one had three, and four had four copies.
• One year post-treatment, among four patients with two SMN2 copies, one walked independently, and three stood with support; by 24 months, three walked independently.

Conclusions:

• Pre-symptomatic treatment for SMA significantly enhances motor function development.
• Large-scale newborn screening programs are vital to prevent diagnostic delays and ensure prompt, effective treatment for SMA.
• Establishing validated care protocols is necessary to facilitate early diagnosis and intervention for SMA.