Half-life of Plasma Phytosterols in Preterm Infants on Parenteral Nutrition

Study Overview
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Brief Summary
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The purpose of this study is to determine plasma phytosterols half-lives in preterm infants who received intravenous soy oil-based lipid emulsions.

Detailed Description
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Several studies reported the relationship between plasma phytosterol concentrations and parenteral nutrition-associated cholestasis (PNAC). Information on plasma phytosterols half-lives in very-low-birth-weight (VLBW) preterm infants on lipid parenteral nutrition (PN) are lacking. In a prospective cohort study, plasma phytosterols (campesterol, stigmasterol and sitosterol) of VLBW preterm infants on routine PN will be measured by gas chromatography-mass spectrometry (GC-MS) during PN administration and after only lipid stopping. Plasma phytosterols half-lives will be calculated from the monoexponential decay curves. Blood samples will be weekly collected from 1st to 7th week of life during routine metabolic tolerance analysis or gas-analysis in order to avoid burden of additional phlebotomy. Samples will be collected in ethylenediaminetetraacetic acid-tubes and immediately centrifugated. Plasma will be stored in pyrogallol added-tubes at -20°C until analysis. Saponification reaction will be done using 5-alpha-cholestane as internal standard.

Official Title
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Half-life of Plasma Phytosterols in Very Low-birth-weight Preterm Infants on Routine Parenteral Nutrition With Soy-bean Oil Based Lipid Emulsions

Conditions
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Liver Diseases

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 24 weeks < gestational age < 32 weeks; 500 g ≤ birth weight < 1250 g; parenteral nutrition with soy oil-based lipid emulsions from the first hours of life; parental consent. Exclusion Criteria: length of parenteral nutrition > 24 days; severe malformations; inborn errors of metabolism; severe congenital sepsis; liver dysfunctions.

Ages Eligible for Study
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Minimum Age: 24 Weeks
Maximum Age: 32 Weeks

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of plasma phytosterol concentrations in preterm infants during parenteral nutrition and after only lipid stopping. | Plasma campesterol, stigmasterol and sitosterol concentrations will be measured at 7, 14, 21, 28, 35, 42 and 49 days from PN started. Plasma phytosterol concentrations will be measured by gas chromatography-mass spectrometry. Calibration curves will be used to calculate the phytosterol plasma concentrations (mg/L). | 7, 14, 21, 28, 35, 42 and 49 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Normal liver function of preterm infants will be define by conjugated bilirubin values from blood samples under 1 mg/dl. | Eligibility of preterm infants will be related to a normal liver function. Conjugated bilirubin value from blood sample is a good sign of hepatic function. The threshold value was defined to 1 mg/dl. Preterm infants who will have conjugated bilirubin values more of 1 mg/dl will be excluded from the study. The measure of conjugated bilirubin from blood samples will be routinely done at 7 and 42 days of life. | 7 days and 42 days of life | 
| Plasma phytosterols half-lives | Plasma phytosterol half-lives (days) will be measured using 3 or more plasma phytosterol concentrations calculated after only lipid stopping. Half-life of plasma phytosterols will be calculated from monoexponential decay curves. | After the collection of 3 or more blood samples collected when the lipid infusion is stopped. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Preterm Infants, Phytosterols, Parenteral Nutrition