Small and Mighty: Micronutrients at the Intersection of Neonatal Immunity and Infection.

Micronutrients are essential dietary components that regulate many biologic functions, including the immune response, and are required in small amounts (typically milligrams or less) in humans. Examples of micronutrients known to affect immune function include several trace minerals (such as zinc and selenium) as well as vitamins (including vitamins A and D). Deficiencies of specific micronutrients are associated with an increased risk of infection in infants in the NICU. Identifying micronutrient supplementation strategies during this period may result in low-cost interventions to reduce the burden of neonatal infectious disease. Many replacement trials thus far demonstrate conflicting results about whether micronutrient supplementation decreases the incidence or severity of sepsis in the neonatal period. The baseline incidence of micronutrient deficiency is important to consider but is often unknown as clinical assessment of micronutrient status occurs infrequently. Future research is needed to clarify the clinical scenarios in which optimizing micronutrient status in term and preterm infants may prevent infection or improve outcomes in those patients who become infected.