Congenital myasthenia with congenital endplate acetylcholinesterase deficiency (Q104865)

Autosomal recessive endplate Acetylcholinesterase (AChE) deficiency, a Congenital myasthenic syndrome (CMS) subtype caused by Collagenic tail of endplate acetylcholinesterase (ColQ) mutations with onset from birth to 2 years, presents with hypotonia and proximal muscle weakness or delayed motor milestones. Extraocular muscle weakness and ptosis are always present, bulbar symptoms in half of the patients, respiratory crises in one-third. Occasionally delayed pupillary light reflex. The course varies from progressive severe weakness in the neonate to less severe symptoms during childhood with minimal progression. More than 80% is ambulant on follow-up and has no respiratory trouble despite crises. The patients respond to ephedrine and salbutamol, not to AChE inhibitors.