Benefit of Salbutamol for the Treatment of Neuromuscular Junction Dysfunction in Patients With Purine-Rich Element Binding Protein A (PURA) Syndrome.

Purine-rich element-binding protein A (PURA) syndrome is a rare neurodevelopmental disorder caused by pathogenic variants in the PURA gene and is characterized by neonatal hypotonia, feeding difficulty, respiratory dysregulation, and severe developmental impairment. The PURA gene has recently been identified as a cause of congenital myasthenic syndrome. We report two unrelated infants with genetically confirmed PURA syndrome who were treated with neuromuscular junction-directed therapy and reviewed three additional published cases. All five patients had neonatal hypotonia and apnea or respiratory failure requiring respiratory support. Pyridostigmine was used in four of the five infants included with heterogeneous response, while salbutamol, used in three patients, was associated with clinical benefit in all. These findings suggest that neuromuscular junction dysfunction may contribute to the respiratory and motor phenotype in patients with PURA syndrome. Early consideration of salbutamol, with careful monitoring and objective outcome measurement, may help stabilize severe infantile respiratory failure and improve motor function.