To the Editor.— We read with great interest the review by Dr Burton on inborn errors of metabolism.1 These myriad disorders frequently present with clinical manifestations that are associated with a variety of more common neonatal diseases. Dr Burton is to be commended for presenting a lucid, rational approach for the diagnosis of these oft-confusing afflictions. However, there is another manifestation of these disorders, not previously recognized in the pediatric literature, that we wish to address.