Plasma cholinesterase deficiency in a neonate.

We report a two-day-old infant who had a period of apnoea lasting six hours following the intravenous administration of succinylcholine (Sch). The results of her plasma cholinesterase level and dibucaine number indicate a congenital absence of plasma cholinesterase (PChE) enzyme, although both parents and siblings had normal cholinesterase levels and dibucaine numbers. This is believed to be the youngest reported case of prolonged apnoea after the administration of succinylcholine.