Effects of manganese from a commercial multi-trace element supplement in a population sample of Canadian patients on long-term parenteral nutrition.

BACKGROUND: Long-term parenteral nutrition (PN) can be associated with micronutrient deficiency or toxicity depending on supplementation. Recently, hypermanganesemia and potential neurological toxicity were reported. The aim of this study was to assess the effect of manganese supplementation in a sample of patients on long-term PN receiving manganese (Mn) as part of a multi-trace element (TE) supplement. METHODS: A convenience sample of 16 patients underwent clinical and blood biochemical measurements as well as magnetic resonance imaging (MRI) of the brain. Descriptive statistics were performed. RESULTS: The mean daily Mn supplementation was 7.28 ± 0.97 µmol/d (400 ± 53 µg/d), which was within the American Medical Association Nutrition Advisory Group guidelines of 2.73-14.56 µmol/d (150-800 µg/d) but exceeded the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) 2002 recommendations of 1.09-1.82 µmol/d (60-100 µg/d). The mean whole blood Mn level was 1.38 ± 0.29 times the upper limit of normal (ULN), and 8 of 14 patients with blood measurements had Mn levels above ULN. On MRI, 81% of patients had high signals on T1-weighted images assumed to be Mn deposits in their basal ganglia. Two patients with positive MRI (15%) had a clinical diagnosis of Parkinson disease. Multiple neuropsychiatric complaints were reported, including depression (66%), lack of concentration (42%), memory disturbances (17%), and gait instability (8%). CONCLUSION: These results suggest that Mn status is elevated in these patients. Manganese supplementation should be used with caution in patients receiving long-term PN, and attention should be paid to the Mn content of multi-TE supplements.

Prescription of trace elements in adults on home parenteral nutrition: current practice based on the Canadian Home Parenteral Nutrition Registry.

BACKGROUND: Since the introduction of long-term parenteral nutrition (PN), morbidity due to inadequate replacement or toxicity of routinely administered trace elements has been well described. After decades of experience, much debate still exists about optimal supplementation. In practice, trace elements (TEs) seem to be frequently provided by prescribing an all-inclusive commercial multi-TE admixture with little dosage flexibility. AIM: Our goal was to review TE supplementation practice among 5 PN support centers across Canada, through a retrospective review of the Canadian Home PN Registry. METHODS: Baseline demographic, clinical, and biochemical parameters along with information regarding the PN prescription of 135 patients with complete records were retrieved from the registry database collected between 2005 and 2007. TE supplementation prescriptions were compared with recent guidelines as well as between groups of patients with different PN indications and dietary intake status. Consent was signed by all participating patients. RESULTS: The average daily PN concentrations of TE were as follows: zinc, 8.6 ± 5.5 mg (130.92 ± 84.23 µmol); manganese, 452 ± 184 µg (8.22 ± 3.34 µmol); selenium, 78 ± 45 µg (0.99 ± 0.57 µmol); chromium, 11 ± 5 µg (0.21 ± 0.10 µmol); copper, 0.64 ± 0.35 mg (10.11 ± 5.58 µmol); and iodine, 77 ± 42 µg (0.61 ± 0.33 µmol). The mean daily supplementation of zinc, manganese, copper, and selenium exceeded published recommendations. Patients' underlying anatomy or indication for PN did not significantly influence decisions regarding replacement standards. CONCLUSION: Parenteral TE supplementation in Canadian PN programs needs to be reviewed and adjusted according to most current guidelines. This may require a reevaluation of the commercial TE preparations currently available in Canada and potential new products worldwide to avoid oversupplementation and potential toxicity.