Parenteral nutrition refers to a method of providing an individual’s nutritional requirements through a route that bypasses the gastrointestinal tract. It is typically delivered through a PICC line or a central venous catheter, to provide the required macro and micronutrients to an individual who is unable to do via their gastrointestinal tract. Some individuals may acquire part of their nutrition via the parenteral route, as their gastrointestinal tract is partially functioning, such as: burns, multi-organ failure, malabsorption, being unable to meet nutritional requirements after maximal enteral support, and more. Others may receive all their nutrition via the parenteral route, as their gastrointestinal tract is considered non-functional. This is also known as Total Parenteral Nutrition (TPN); examples include, but are not limited to the following: paralytic ileus, bowel obstruction, prolonged bowel rest, small bowel ischemia, necrotizing enterocolitis and GI surgery. Possible complications of parenteral nutrition include aspiration, diarrhea, neurological abnormalities, hyperglycemia, micronutrient deficiencies, refeeding syndrome, constipation and fecal impaction among others. Manganese is a micronutrient that is needed in small amounts; however, hypermanganesaemia may occur because it is a ubiquitous contaminant. This may lead to decreased liver function and cholestasis; furthermore, manganese is a neurotoxic agent that accumulates in the basal ganglia.
Manganese deposition in the basal ganglia may sometimes lead to symptoms of manganese intoxication, such as: psychiatric and behavioural changes and parkinson-like symptoms and signs among others. T1-weighted shows symmetrical hyperintensity in the basal ganglia, especially the globus pallidus and subthalamic nuclei. These changes are reversible if there is a reduction in manganese supplementation. However, T2-weighted images should do show these abnormalities.
References:
1. Kafritsa, Y., Fell, J., Long, S., Bynevelt, M., Taylor, W., & Milla, P. (1998). Long term outcome of brain manganese deposition in patients on home parenteral nutrition. Archives of Disease in Childhood, 79(3), 263–265.
2. Jin, J. , Saqui, O. and Allard, J. P. (2018), 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. Journal of Parenteral and Enteral Nutrition, 42: 164-170. doi:10.1177/0148607117690519