LGMD2i (also called “LGMD R9 FKRP-related” in the new proposed nomenclature) is an inherited disease caused by a mutation in the FKRP gene. Although the disease is primarily diagnosed in adolescents 10 – 20 years old, children have been diagnosed as young as two years old. Patients with LGMD2i experience progressive muscle weakness, that affects skeletal, respiratory and cardiac muscles. While every patient experience is different, muscle weakness typically begins in the shoulder and hip areas, resulting in the need for assistance with mobility.
The FKRP gene is involved in helping muscles build a glycoprotein called alpha dystroglycan. Alpha dystroglycan acts as a “shock absorber,” and when it doesn’t work correctly, as occurs in patients with LGMD2i, the shock absorbing function is significantly reduced. This leads to damage to muscle tissue and replacement, over time, with scar-like, fibrotic tissue. As fibrotic tissue overtakes healthy muscle tissue, muscle strength and function declines, and patients lose the ability to perform routine daily activities unassisted – such as walking or standing up.
Over time, muscle degeneration can become so excessive as to result in respiratory and cardiovascular issues, leading to respiratory or cardiac arrest and death. Currently, people with LGMD2i have no treatment options beyond steroid injections and other symptom and pain management techniques. The LGMD2i community has made exceptional strides to spread awareness of the unmet medical need, as well as to create a network connecting patients with physician experts in the field of neuromuscular diseases.
For additional information and resources, several advocacy organizations are working to help people diagnosed with LGMD2i as well as their families. Links to specific sites are below.