![]() ![]() ![]() Interferon, IL-1, and tumour necrosis factor enhance ferritin synthesis resulting in a shift of cellular iron into a storage compartment and downregulate transferrin receptor production decreasing cellular iron uptake and, thereby, iron availability for intracellular pathogens ( 5). Furthermore, the antibacterial effect of cytokines is mediated by intracellular iron depletion. Iron availability correlates with bacterial growth and virulence, facilitates viral replication and reverses the bactericidal effect of lactoferrin and lysozyme ( 3,4). There is, therefore, an argument for curtailing iron supplementation at lower plasma ferritin concentration.Ī further concern over parenteral iron administration is that it may impair immune function and stimulate bacterial growth thus increasing the risk of infection by iron-requiring pathogens ( 2). ![]() Although Ben-Hariz et al suggested halving iron intake at ferritin concentrations of 500 ng/ml and stopping completely at 1000 ng/ml, these concentrations probably leave only a small margin of safety. Thus, iron status of children receiving long-term PN should be monitored by regular measurement of serum ferritin, and supplementation decreased if ferritin concentration is raised. The degree of iron deposition in either hepatocytes or Kupffer cells was most pronounced in children with the higher ferritin concentrations (( 1) (LOE 2+)). Ferritin concentrations were >800 ng/ml in eight children (>1100 ng/ml in five) and correlated with duration of PN. In a study of 30 children aged 1-18 years receiving ferrous sulphate 100 μg/kg per day for an average period of 43 months, 12 children showed evidence of plasma and hepatic iron overload. An accumulation of excess iron has been reported in children receiving prolonged parenteral nutrition. Parenteral administration of iron bypasses the homeostatic control of gastrointestinal iron absorption, causing loss of protection from iron overload if excessive quantities are provided. One major concern is that of iron overload. Currently there are no well-defined recommendations regarding the optimum content of iron in parenteral feeds, and intravenous administration of iron remains problematic. Iron is not routinely provided in parenteral nutrition mixtures and is often not a component of commercially available trace element preparations. Key Words: calcium, chromium, copper, iodine, iron, manganese, magnesium, molybdenum, newborn, parenteral nutrition, phosphorus, selenium, trace elements, zinc. Type of publications: randomised controlled studies case-control or cohort studies case reports case series expert opinion. Timeframe: 1990-2004, in addition relevant earlier publications were considered. ![]()
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