Effect of Discontinuation of Manganese Supplementation From Home Parenteral Nutrition Solutions on Whole-Blood Levels and Magnetic Resonance Imaging of the Brain: A 5-Year Cohort Study.

Abstract

Manganese (Mn) is included in current premixed multiple trace element (TE) additives for home parenteral nutrition (HPN). However, there is a risk of oversupplementation of Mn due to contamination from PN additives. Oversupplementation can produce Mn toxicity with neurologic symptoms and abnormalities on brain magnetic resonance imaging (MRI). In 2009, we reported that whole-blood Mn levels were above the upper limit of normal in 16 HPN patients, with 81% having MRI findings. Subsequently, we removed Mn supplementation from all our HPN patients. We present a 5-year follow-up here. This is a prospective cohort study on 11 of the surviving 16 patients on HPN. All patients had Mn removed from PN and had yearly monitoring of blood Mn levels. Eight patients had a repeat MRI to evaluate for resolution of basal ganglia deposits. Patient demography, clinical history, and bloodwork were recorded. Five of 6 patients who initially had elevated Mn levels had normal levels on follow-up. All patients who had Mn levels measured serially had a decrease in levels; the mean percent decrease of Mn was 38.1% (range, 10.1%-53.8%). Two patients had elevated Mn despite the absence of supplementation. Six of 8 patients who had repeat MRIs had complete resolution abnormalities. Removal of Mn as an additive in HPN solutions resulted in resolution of MRI abnormalities in most patients. Over 5 years, all patients except for 1 maintained normal blood Mn levels. Therefore, Mn levels should be monitored and supplementation be individualized.