LRP4-Related Congenital Myasthenic Syndrome: Clinical, Pathophysiological, and Therapeutic Aspects.

Congenital Myasthenic Syndrome represents a complex and heterogeneous group of inherited neuromuscular disorders, which result from variants in genes involved in different pathophysiological mechanisms related to the neuromuscular junction. LRP4 (Low-density lipoprotein receptor-related protein 4) represents one of the most important proteins involved in this complex signaling pathway, acting in a complex with agrin and Muscle Skeletal Receptor Tyrosine Kinase (MuSK) proteins. LRP4 became known to most neurologists due to the description of anti-LRP4 antibody-related Myasthenia Gravis. There are, however, different neurological and neuromuscular disorders that result from pathogenic variants in LRP4 gene, especially a rare and potentially treatable Congenital Myasthenic Syndrome. The authors performed a detailed narrative review, including descriptions of the main pathophysiological, clinical, and therapeutic aspects of LRP4-related Congenital Myasthenic Syndromes.