Hypotonic Infant with PURA Syndrome-Related Channelopathy Successfully Treated with Pyridostigmine

PURA syndrome is a rare, clinically heterogeneous disorder characterized by a wide spectrum of neurodevelopmental problems, and occasionally congenital heart defects, urogenital malformations, skeletal abnormalities and endocrine disorders. We describe the hospital course, diagnostic evaluations as well as neurologic and neuromuscular follow up of an infant diagnosed with PURA syndrome based on a pathogenic deletion at c.697_699 (p.Phe233del) of the PURA gene identified on whole exome sequencing. Upon initial examination, fluctuation of neuromuscular tone and reflexes were noted in conjunction with hypotonia and severe apneic episodes, suggestive of neuromuscular junction involvement. A definitive role of the neuromuscular junction has not been previously reported with PURA syndrome. The infant was started on pyridostigmine, an acetylcholinesterase inhibitor, with significant improvement in neuromuscular tone and motor movements. In addition, pyridostigmine also resulted in resolution of apneas and improved respiratory status which suggests its potential therapeutic role in patients with PURA syndrome.