Clinical Research Asymptomatic Hypermanganesemia in Long-Term Home Parenteral Nutrition Patients

Manganese (Mn) is considered a trace element, which serves as an activator for several enzyme systems. Despite a general agreement that Mn is essential, cases of Mn deficiency are rare. In addi-tion, the Food and Drug Administration has not set a recommended dietary allowance for Mn. Manga-nese is commonly added to parenteral nutrition (PN) solutions. Manganese is most frequently supplied in the form of a multiple trace element (MTE) addi-tive.1 Using these MTE products, the most common dose of Mn given to adults receiving home PN (HPN) is 0.5 mg daily. Performance changes have been observed in Mn-deficient rats given ethanol.2 In humans, deficien-cies of Mn have been poorly documented. On th