When to Consider an Inborn Error of Metabolism in Adults?

Inborn errors of metabolism (IEM) are a group of disorders that are often erroneously assumed to be the playing field of pediatricians only. This misconception combined with the rare nature of IEMs explains why there is often a serious delay in the diagnosis of an adult-onset IEM, which can have detrimental consequences. This review provides potential strategies to overcome this diagnostic delay. The most promising consists of stimulating critical clinical reasoning and creating awareness of the process that leads to the diagnosis of a rare disease.