Manganese Provision in Parenteral Nutrition: An Update

Abstract

Manganese (Mn) is an essential micronutrient required for the activity of metalloenzymes. It is an essential component of parenteral nutrition (PN), but requirements are low. Mn status is difficult to assess, with the commonest method being measurement of its concentration in whole blood. This method has limitations, including artifactually high concentrations resulting from contamination of specimen tubes. Mn toxicity is a well-recognized complication of PN, the risk of which increases if there is cholestasis or if the patient has received high doses. It usually presents with parkinsonian-like symptoms but may be detected presymptomatically as hypermanganesemia or as increased signal intensity of the basal ganglia upon T1-weighted magnetic resonance imaging. Caution is necessary when providing Mn for patients on long-term PN (>1 month). It is advisable to withhold supplementation if hypermanganesemia or cholestasis develops. Deficiency of Mn is rare in patients treated with PN. PN regimens are contaminated with Mn in amounts likely to meet requirements. Consequently, it is debated whether PN should be routinely supplemented with Mn. The currently recommended dose of Mn in adults treated with PN is 55 μg/d, but the doses provided by most currently available multi-trace element products exceed this. In response to calls for new products to be developed, 2 new multi-trace element products are currently available in Europe that provide Mn doses of 55 μg/d. Once these products are in general use, it is likely that the incidence of Mn toxicity will decrease.

Quantitative Assessment of Trace‐Element Contamination in Parenteral Nutrition Components

“…Manganese and chromium are required by the human body to facilitate a plethora of vital enzymatic processes, but oversupplementation can be detrimental . In 2001, Dickerson compiled reports of nearly 400 individuals treated with PN who developed hypermanganesemia .…”

“…Two manifested clinically relevant Parkinsonian‐like symptoms . The risk of toxicity is increased even further in liver disease when biliary excretion is impaired, as decreased clearance can lead to manganese accumulation in the liver and brain . Chromium toxicity is rare and not as well characterized.…”

Manganese Enhanced MRI for Use in Studying Neurodegenerative Diseases

“…However, in these cases the patients received long-term parenteral nutrition (>1 month), showed very high whole blood manganese concentrations and in some cases developed parkinsonian-like symptoms. No signal change was detected in the brain of control patients and low manganese exposure patients (Quaghebeur et al, 1996; Aschner et al, 2015; Livingstone, 2018). With these limitations, parenteral nutrition may be useful for some clinical applications of MEMRI.…”

Elevated Whole‐Blood Manganese Levels in Adult Patients Prescribed “Manganese‐Free” Home Parenteral Nutrition

“…Additional Mn exposure is known to occur as a result of contamination via PN additives, 7 likely at a level to meet requirements. 8 Recommended standard doses of Mn in PN for adults have been decreasing (Table 1). [9][10][11][12][13] In 2014, a previous review at our institution observed 60% of home PN (HPN) patients to have high whole-blood Mn levels.…”

“…Mn is typically provided as part of a commercially available premixed multi‐TE (MTE) solution in all patients receiving parenteral nutrition (PN). Additional Mn exposure is known to occur as a result of contamination via PN additives, 7 likely at a level to meet requirements 8 . Recommended standard doses of Mn in PN for adults have been decreasing (Table 1).…”