Plasma and urine riboflavin during riboflavin-free nutrition in very-low-birth-weight infants

BACKGROUND: Very-low-birth-weight (VLBW; birth weight <1500 g) infants receive enteral and parenteral nutriture that provides greater daily riboflavin (vitamin B2) than does term infant nutriture, and elevated plasma riboflavin develops in these infants after birth. The purpose of this study was to measure plasma and urine riboflavin concentrations in VLBW infants during riboflavin-free nutrition. Our hypothesis was that elevated plasma riboflavin develops in VLBW infants because of high daily intake and immature renal riboflavin elimination. METHODS: Eighteen clinically healthy VLBW infants received parenteral nutrition and preterm infant formula during the first postnatal month. On postnatal days 10 and 28, the infants received specially prepared riboflavin-free enteral and parenteral nutrition for the 24-hour study period. Serial collections of plasma were made at time 0 and at 12 and 24 hours. Urine was collected continuously for the 24-hour period in 4-hour aliquots. Samples were analyzed for riboflavin concentration. RESULTS: During the 24-hour riboflavin-free study period on postnatal day 10, plasma riboflavin decreased 56% from 185 +/- 37 ng/mL (mean +/- SEM), and urine riboflavin decreased 75% from 3112 +/- 960 mg/mL. Similarly, on postnatal day 28, plasma riboflavin decreased 79% from 184 +/- 32 ng/mL, and urine riboflavin concentration decreased 91% from 5092 +/- 743 ng/mL during the 24-hour riboflavin-free study period. Riboflavin half-life (t(1/2)) was 18.5 hours on postnatal day 10 and decreased 48% by postnatal day 28. Riboflavin elimination was 145.1 +/- 20.6 mg/kg per day on postnatal day 10 and increased 40% by postnatal day 28. CONCLUSION: The VLBW infants who received parenteral nutrition and preterm infant formula had elevated plasma riboflavin on postnatal days 10 and 28. Plasma riboflavin t(1,2) was shorter and renal riboflavin elimination was greater on postnatal day 28 than on postnatal day 10. Plasma riboflavin was normal after 24 hours of riboflavin-free nutrition. The pattern of plasma and urine riboflavin in VLBW infants suggests a lower daily intake would maintain plasma riboflavin close to normal.     

Vitamin concentrations in very low birth weight infants given vitamins intravenously in a lipid emulsion: measurement of vitamins A, D, and E and riboflavin

Because total parenteral nutrition with vitamins added to the glucose-amino acid mixture is often associated with a reduction in blood levels of vitamin A (retinol) during the routine treatment of many very low birth weight (VLBW) infants (less than 1500 gm), and because retinol losses in the plastic delivery system can be prevented by adding the vitamins to an intravenous lipid emulsion, seven VLBW infants with a mean birth weight of 900 gm (range 450 to 1360 gm) were given 40% of a unit dose vial, per kilogram of body weight, of a multivitamin preparation (M.V.I. Pediatric) (280 micrograms retinol; 160 IU vitamin D; 2.8 mg tocopherol; 0.68 mg riboflavin) in a lipid emulsion, Intralipid. After treatment with the intralipid-vitamin mixture for 19 to 28 days, plasma vitamin A (retinol) concentrations increased significantly from 11.0 +/- 0.76 (mean +/- SEM) before intralipid to 19.2 +/- 0.97 micrograms/dl after the intralipid-vitamin mixture (p less than 0.01); 25-hydroxyvitamin D concentrations increased from an initial value of 12.6 +/- 2.6 to 20.2 +/- 1.9 mg/dl (p less than 0.01); alpha-tocopherol concentrations increased from an initial value of 0.31 +/- 0.06 to 2.44 +/- 0.13 mg/dl (p less than 0.01); and riboflavin levels increased from 64.1 +/- 7.8 ng/ml to concentrations between 20 and 100 times the initial level. Erythrocyte riboflavin levels increased from 71.8 +/- 14 initially to 166 +/- 41 ng/gm hemoglobin, and erythrocyte flavin-adenine dinucleotide levels increased similarly from 972 +/- 112 initially to 2005 +/- 294 ng/gm hemoglobin. These results show that the addition of M.V.I. Pediatric to Intralipid decreases the extensive in vivo loss of retinol and is associated with an increase in plasma retinol concentrations in VLBW infants. The daily doses of vitamins D (160 IU/kg) and E (2.8 mg/kg) appear sufficient, but the dose of vitamin A (280 micrograms/kg) is insufficient to raise blood levels of all infants into the normal range. The current dose of riboflavin is excessive and may be harmful.     

Plasma vitamin E concentrations of older infants fed cow's milk or infant formula.

Nutrition of older infants, though important for optimal brain development, is inadequately studied. The beverage choice markedly influences nutrient intake, but little is known regarding nutrition status of older infants, particularly for vitamin E. This study assessed vitamin E intakes and plasma tocopherol concentrations in two groups of healthy infants, 8 to 13 months of age, who had consumed either cow's milk (n = 45) or milk-based formula (n = 55) for a minimum of the 3 preceding months. Mean (+/- SEM) vitamin E intake was significantly lower (p < or = 0.001) by the infants who had consumed cow's milk (CMF) than by infants who had consumed formula (FF); 4.1 +/- 0.25 mg/day and 10.9 +/- 0.57 mg/day, respectively. Mean (+/- SEM) intake of linoleic plus linolenic acids was significantly lower (p < or = 0.005) by CMF infants (3.4 +/- 0.2 g) than by FF infants (9.9 +/- 1.0 g), although mean (+/- SEM) dietary vitamin E to polyunsaturated fat ratio (E/PUFA ratio) was the same in both FF and CMF infants (1.3 +/- 0.1). Plasma alpha-tocopherol concentration (mean +/- SD) was significantly lower (p < or = 0.005) in CMF than in FF infants (0.86 +/- 0.28 mg/dl vs. 1.14 +/- 0.42 mg/dl, respectively). Dietary vitamin E intakes were positively correlated (p < or = 0.05) with plasma alpha-tocopherol concentrations. No correlations were found between plasma alpha-tocopherol concentrations and total fat intake, dietary E/PUFA ratios, erythrocyte polyunsaturated fatty acids > or = C18:2, or number of hours postprandial that blood was drawn.(ABSTRACT TRUNCATED AT 250 WORDS)     

Thiamine, riboflavin, pyridoxine, and vitamin C status in premature infants receiving parenteral and enteral nutrition

BACKGROUND: There is a paucity of data about water soluble vitamin status in low birthweight infants. Therefore, the authors' objective was to assess current feeding protocols. METHODS: The authors measured serum concentrations for riboflavin, pyridoxine, and vitamin C and functional assays for thiamine and riboflavin longitudinally in 16 premature infants (birthweight, 1,336 +/- 351 g; gestational age, 30 +/- 2.5 weeks) before receiving nutrition (time 1, 2 +/- 1 days), during supplemental or parenteral nutrition (time 2, 16 +/- 10 days) and while receiving full oral feedings (time 3, 32 +/- 15 days). In plasma, vitamin C was measured colorimetrically, and riboflavin and pyridoxine were measured using high-performance liquid chromatography. The erythrocyte transketolase test as a functional evaluation of thiamine and the erythrocyte glutathione reductase test for riboflavin were measured colorimetrically. RESULTS: At time 1, nutrient intake of vitamins were negligible because infants were receiving intravenous glucose and electrolytes only. Intakes differed between time 2 and time 3 for thiamine (510 +/- 280 and 254 +/- 115 microg. kg-1. d-1, respectively), riboflavin (624 +/- 305 and 371 +/- 193 microg. kg-1. d-1, respectively), and pyridoxine (394 +/- 243 and 173 +/- 85 microg/100 kcal, respectively), but not for vitamin C (32 +/- 17 and 28 +/- 12 mg. kg-1. d-1, respectively). Blood levels at times 1, 2, and 3 were for thiamine (4.9 +/- 2.7%, 3.3 +/- 6.6%, and 4.1 +/- 9% erythrocyte transketolase test, respectively), riboflavin (0.91 +/- 0.31, 0.7 +/- 0.3, 0.91 +/- 0.18 erythrocyte glutathione reductase test, respectively), riboflavin (19.5 +/- 17, 23.3 +/- 8.6, 17.6 +/- 10 ng/mL, respectively), pyridoxine (32 +/- 25, 40 +/- 16, 37 +/- 26 ng/mL, respectively), and vitamin C (5.2 +/- 3, 5 +/- 2.2, 10 +/- 5 microg/mL, respectively) and did not differ at those times. CONCLUSIONS: Current intakes of these vitamins, except for possibly vitamin C, during parenteral and enteral nutrition seem to result in adequate plasma concentrations and normal functional indices.     

Vitamin E status in preterm infants fed human milk or infant formula

Vitamin E status was assessed in 36 infants with birth weights less than 1500 gm who were assigned randomly to receive one of three sources of nutrition: milk obtained from mothers of preterm infants (preterm milk), mature human milk, or infant formula. Infants in each dietary group were further assigned randomly to receive iron supplementation (2 mg/kg/day) beginning at 2 weeks or to receive no iron supplementation. All infants received a standard multivitamin, providing 4.1 mg alpha-tocopherol daily. Serum vitamin E concentrations at 6 weeks were significantly related both to type of milk (P less than 0.0001) and to iron supplementation (P less than 0.05). Infants fed preterm milk had significantly higher serum vitamin E levels than did infants fed mature human milk, and both groups had significantly higher levels than did those fed formula. Ratios of serum vitamin E/total lipid were also significantly greater for infants fed human milks than for those fed formula. The addition of iron to all three diets resulted in significantly lower serum vitamin E levels at 6 weeks (P less than 0.05); however, only in the group fed formula was there evidence of vitamin E deficiency. Preterm milk with routine multivitamin supplementation uniformly resulted in vitamin E sufficiency in VLBW infants whether or not iron was administered.     

Improved vitamin A supplementation regimen for breastfed very low birth weight infants

OBJECTIVE: Preterm infants usually have low retinol status at birth and at discharge from hospital. We have evaluated a new protocol designed to improve plasma retinol in very low birth weight infants (VLBW, birth weight < 1500 g). DESIGN: An open intervention trial was conducted in which vitamin A was given in a human milk fortifier. The daily dose of vitamin A varied according to bodyweight and was given mixed with human milk instead of as a bolus. Blood samples were collected at inclusion and at discharge from hospital. Plasma was analyzed for retinol using high-performance liquid chromatography. The daily intake of vitamin A and plasma retinol concentration was compared with the vitamin protocol normally used in Norwegian hospitals. RESULTS: Sixty VLBW infants were included and 53 completed the study. At discharge from hospital, the reference group had lower median plasma retinol concentrations compared to the modified group (0.30 microM vs. 0.49 microM, p = 0.008). Fewer infants in the modified group had plasma retinol levels below 0.35 microM (indicating reduced hepatic stores) compared to infants in the reference group (44% vs. 69%, p = 0.04). CONCLUSION: The modified protocol improved plasma retinol levels at discharge compared to the reference protocol.     

Serum concentrations of vitamin E in healthy infants fed commercial milks

Serum vitamin E concentrations were determined in 60 term and 26 premature infants during the first 2 months of life. All infants received commercial milk formula containing vitamin E. In addition, premature infants older than 10 days were given vitamin E orally as a multivitamin preparation. Thus, daily intake of vitamin E was nearly 1.2 mg/kg body weight in term infants and 2–3 mg/kg body weight in premature infants.In term infants serum levels of vitamin E rose from 2.6 mg/l (cord blood) to 7.0 mg/l (3rd–13th day) and 9.1 mg/l (16th–25th day) and remained at 10 mg/l (in the second month of life). Hemoglobin concentration and red cell number decreased continuously due to physiological anemia of infancy. In premature infants mean values of vitamin E were the same as in term infants. Vitamin E deficiency with hemolytic anemia could be demonstrated in a 2 months old infant suffering from cystic fibrosis.Dedicated to Prof. Dr. H.-R. Wiedemann on the occasion of his 65th birthday     

Increased parenteral amino acid administration to extremely low-birth-weight infants during early postnatal life

BACKGROUND: Early administration of parenteral amino acids to infants with extremely low birth weight (birth weight < or = 1,000 g) has been encouraged to foster growth. However, excessive intravenous intake of amino acids may cause metabolic acidosis and uremia in extremely low birth weight infants. The hypothesis for this study was that extremely low birth weight infants would tolerate slightly increased early postnatal parenteral amino acid administration and benefit. METHODS: The peak daily parenteral amino acid dosage was increased from 3 g/kg (standard group) to 4 g/kg (modified group). The corrected parenteral amino acid dosage was computed to account for enteral protein intake and keep the combined daily intravenous amino acid and enteral protein intake at or below 3 g . kg -1 . d -1 in the standard group and 4 g . kg -1 . d -1 in the modified group. The primary outcome measure was plasma bicarbonate concentration as an indicator of acid-base status. Data were collected for patient demographics, nutritional intake, serum bicarbonate and serum urea nitrogen concentrations, and outcome. RESULTS: The corrected parenteral amino acid intake of the modified group was 16% greater at postnatal week 1 (3.30 +/- 0.83 g . kg -1 . d -1; mean, +/-1 SD) and 18% greater (3.86 +/- 0.94 g . kg -1 . d -1 ) at postnatal week 2 than the parenteral amino acid intake of the standard group. In the modified group, the mean serum bicarbonate concentration was 19.1 +/- 1.8 mEq/dL at week 1 and 23.9 +/- 2.9 mEq/dL at week 2, with no difference between the groups. At week 1, serum urea nitrogen concentrations were the same in both groups. The mean serum urea nitrogen concentration of the modified group at postnatal week 2 (18.2 +/- 8.8 mg/dL) was unchanged from postnatal week 1, but was greater than that of the standard group at postnatal week 2. Weight gain was the same in both groups. Corrected parenteral amino acid intake at postnatal week 1 correlated directly with weight gain from birth to postnatal week 2 ( P < 0.03) in both groups. CONCLUSIONS: Infants with extremely low birth weight tolerated parenteral amino acid intake of approximately 4 g . kg -1 . d -1. Mild increases of mean serum urea nitrogen concentration and mean weight gain were associated with increased parenteral amino acid administration without significant acidosis.     

Distribution of plasma vitamin E levels in supplemented very low birthweight infants

The distribution of plasma Vitamin E (VE) was determined in 25 very low birthweight (VLBW) infants who were supplemented with 100 mg/kg per day of alpha-tocopherol acetate, given intragastrically. Their mean birthweight was 917 g and mean gestational age was 28 weeks. Mean plasma VE levels after 1 and 6 weeks' supplementation were 2.7 mg/dL (s.e.m. = 1.0) and 6.4 mg/dL (s.e.m. = 1.4), respectively (the difference was not significant). There was wide variability in plasma VE levels in these infants despite being on an identical dose of tocopherol. Plasma VE was less than 0.5 mg/dL in 12% of samples, 0.5-3.0 mg/dL in 32%, 3.1-5.0 mg/dL in 18%, and 5.1-20 mg/dL in 38%. Fifteen of the 25 infants had at least one level in the range which has been associated with an increased incidence of septicaemia and necrotizing enterocolitis (greater than 5.0 mg/dL). These data suggest that if a policy of VE supplementation for VLBW infants is chosen, monitoring of plasma VE levels appears necessary so that the dosage can be adjusted in order to maintain plasma VE within the optimal range. This study's dosage regimen of supplementing infants with 100 mg/kg per day of VE was associated with a high incidence of elevated plasma VE levels and it is concluded that it is not advisable to use such large doses of VE in the premature newborn.     

Evaluation of a pediatric multiple vitamin preparation for total parenteral nutrition. II. Blood levels of vitamins A, D, and E

This study represents the first attempt to evaluate the American Medical Association Nutrition Advisory Group (NAG) recommendations for intravenous vitamin A, D, and E dosages for infants and children. Patients studied included 18 preterm infants (group 1) and 26 term infants and children (group 2A) receiving total parenteral nutrition for 2 to 4 weeks and eight infants and children receiving total parenteral nutrition for 3 to 6 months (group 2B). Term gestation infants and children up to 11 years of age all received the same dosages (those that were recommended by the NAG for children weighing more than 10 kg). Preterm infants received 65% of these doses. In group 1, cord blood alpha-tocopherol levels were less than 0.22 mg/dL in seven preterm infants (reference value = 0.29 +/- 0.04), but mean levels increased to 1.65 +/- 0.17 mg/dL after four days of treatment. Eight infants consistently received additional vitamin E orally (80 to 150 mg daily), and their levels increased to 2.18 +/- 0.26 mg/dL by four days of study and to 3.49 +/- 0.57 mg/dL after 3 weeks. Oral supplementation in the preterm infants appeared to be unnecessary because intravenous vitamins alone maintained levels above 1.1 mg/dL. In group 2, alpha-tocopherol levels were maintained within the reference range. Patients receiving lipid emulsions containing substantial quantities of alpha-tocopherol had significantly higher blood levels than patients receiving lipid emulsions containing little alpha-tocopherol (P less than .01). Mean 25-OH vitamin D levels were maintained above or within the reference range in groups 2A and 2B.(ABSTRACT TRUNCATED AT 250 WORDS)     

Minimal vitamin D and high calcium and phosphorus needs of preterm infants receiving parenteral nutrition

Preterm infants (birth weight, 1,089 +/- 91 g; gestational age, 28.9 +/- 0.7 weeks; mean +/- SEM) with mixed medical and surgical indications for parenteral nutrition (PN) were observed to determine the adequacy of infusates with fixed, low-dose vitamin D (25 IU/dl) and two combinations of calcium and phosphorus. The duration of low-dose vitamin D PN ranged from 5 to 52 days, with a median of 27 days. Twelve infants were randomly assigned to low (standard) Ca and P doses (5 mM each; 20 mg/dl of Ca and 15.5 mg/dl of P) and 13 high Ca and P doses (15 mM each; 60 mg/dl of Ca and 46.5 mg/dl of P). The maximum daily vitamin D intake was similar for both groups (31 +/- 1.3 versus 33 +/- 1.2 IU/kg). Vitamin D status in either group, as indicated by serum 25-hydroxyvitamin D (25-OHD) concentrations, was normal. There was no significant difference in observed changes of serial measurements of serum calcium, magnesium, phosphorus, alkaline phosphatase, creatinine (Cr), 25-OHD, and vitamin D-binding protein concentrations or urinary Ca:Cr and Mg:Cr ratios. In the low-dose Ca and P group, the serum P level was consistently less than 4 mg/dl in five infants, serum 1,25-dihydroxyvitamin D concentrations were higher, and tubular reabsorption of phosphorus was consistently greater than 95% and significantly higher than in the high-dose Ca and P groups. Severe bone demineralization apparent on X-ray occurred in two infants, with a fractured distal left ulna in one of the two infants.(ABSTRACT TRUNCATED AT 250 WORDS)     

Supply of vitamin A, E, C, B 12 and folates during total parenteral nutrition in pediatrics]

Serum vitamin A, vitamin E, vitamin B12, folate and leucocyte vitamin C were measured in 45 patients between the ages of one month and 2 1/2 years who were receiving total parenteral nutrition. After allowing for variations in intake the following recommendations are made: Vitamin A (central vein) 2,500 i.u./day (peripheral vein) 1,000 - 1,500 i.u./day. Vitamin E (peripheral vein) 0.8 mg/kg/day, Vitamin B12 (central vein) 0.8 - 1 microgram/day, Folate (central vein) 10 - 80 microgram/day, Vitamin C (central vein) 25 mg/day.     

Vitamin K status of lactating mothers, human milk, and breast-feeding infants

Hemorrhagic disease of the newborn is a disease of breast-feeding newborns. There is little information on longitudinal breast milk concentrations of phylloquinone (vitamin K1) or the effects of maternal phylloquinone supplements on breast milk. In study part 1, 11 lactating mothers, who received 20 mg of phylloquinone orally, had rises in plasma (less than 1 to 64.2 +/- 31.5 ng/mL by 6 hours) and breast milk concentrations (from 1.11 +/- 0.82 to 130 +/- 188 ng/mL by 12 hours). In part 2, 23 lactating mothers and their infants were observed longitudinally along with a formula-fed control group of infants (n = 11). Mean breast milk concentrations of phylloquinone at 1, 6, 12, and 26 weeks were 0.64 +/- 0.43, 0.86 +/- 0.52, 1.14 +/- 0.72, and 0.87 +/- 0.50 ng/mL, respectively, in the infants fed human milk. Maternal phylloquinone intakes (72-hour dietary recalls) exceeded the recommended daily allowance of 1 microgram/kg per day. Infant phylloquinone intakes did not achieve the recommended daily allowance of 1 microgram/kg per day in any infant. Plasma phylloquinone concentrations in the infants fed human milk remained extremely low (mean less than 0.25 ng/mL) throughout the first 6 months of life compared with the formula-fed infants (4.39 to 5.99 ng/mL). In this small sample, no infant demonstrated overt vitamin K deficiency. Despite very low plasma phylloquinone concentrations, vitamin K supplements (other than in the immediate newborn period) cannot be recommended for exclusively breast-fed infants based on these data.     

Serum vitamin D metabolites in very low birth weight infants with and without rickets and fractures

Seventy-one very low birth weight (less than or equal to 1500 gm) infants were studied to determine the sequential changes in serum vitamin D metabolite concentrations between infants with and without radiographically documented rickets, fractures, or both (R/F). Usual intake of vitamin D included 20 IU/kg/day from parenteral nutrition or 400 IU/day supplementation with enteral feeding. Radiographs of both forearms and serum samples were obtained at 3, 6, 9, and 12 months. Twenty-two infants had R/F. At 3 months, significantly lower mean (+/- SEM) serum phosphorus levels (4.5 +/- 0.4 vs 6.1 +/- 0.2 mg/dl), higher 1,25-dihydroxyvitamin D (1,25-[OH]2D) concentrations (96 +/- 5 vs 77 +/- 4 pg/ml), and higher free 1,25-(OH)2D index (1,25-[OH]2D:vitamin D binding protein ratio; 5.2 +/- 0.3 x 10(5) vs 4.0 +/- 0.2 x 10(5] were found in the R/F group. These values returned to normal and were similar between groups on subsequent measurements. Serum calcium, magnesium, and 25-hydroxyvitamin D (25-OHD) concentrations were normal and similar between groups. In both groups, serum vitamin D binding concentrations increased initially but remained stable and normal beyond 6 months. We conclude that in very low birth weight infants with R/F, the vitamin D status (as indicated by serum 25-OHD concentrations) is normal, and that lowered serum phosphorus levels, higher serum 1,25-(OH)2D levels, and a higher free 1,25-(OH)2D index support the thesis that mineral deficiency (especially of phosphorus) may be important in the pathogenesis of R/F in small preterm infants.     

Total parenteral nutrition in sick preterm infants: effects of cysteine supplementation with nitrogen intakes of 240 and 400 mg/kg/day

The effects of supplementing total parenteral nutrition (TPN) solutions with cysteine were assessed at two different levels of nitrogen intake by determining nitrogen retention, sulfate excretion, and sulfur-containing amino acid concentrations. Ten infants received 72 mg/kg/day of cysteine-HCl in a TPN solution for a period of 6 days. Five of these infants received 251 +/- 48 (mean +/- SD) mg/kg/day of nitrogen, and five received 403 +/- 45 mg/kg/day of nitrogen. Two other groups of five infants each received unsupplemented TPN at nitrogen intakes of 235 +/- 48 and 412 +/- 54 mg/kg/day, respectively. Fluid and nonprotein caloric intakes were similar for all four groups. Cysteine supplementation increased plasma and urine free cyst(e)ine concentrations and enhanced total sulfur retention, but did not enhance nitrogen retention. [Cyst(e)ine refers to the mixture in any proportion of the sulfhydryl (cysteine) and the disulfide (cystine) forms of this compound.] Nitrogen retention, sulfate excretion, cyst(e)ine excretion, and plasma taurine concentrations increased as the result of the increase in nitrogen intake.     

Oral vitamin A, E and D supplementation of pre-term newborns either breast-fed or formula-fed: a 3-month longitudinal study

BACKGROUND: In contrast to the studies of vitamin A and E status in children, adolescents and adults, information on preterm infants is scarce. In the present investigation we examined the vitamin A, D and E status of pre-term infants at birth, and verified whether, at 1 and 3 months, breast or formula feeding affected the plasma concentration of those vitamins while being supplemented with Uvesterol ADEC. PATIENTS AND METHODS: In this prospective study, 2 groups of consecutively recruited preterm newborns fed either breast milk or formula received 3000 IU of vitamin A, 5 IU of vitamin E and 1000 IU of vitamin D daily. Vitamin A and E were measured by high performance liquid chromatography and spectrophotometry. 25-hydroxyvitamin D, a surrogate marker for vitamin D status, was measured by radioimmunoassay, and retinol binding-protein concentration was measured by immunonephelometry. RESULTS: At birth, formula-fed and breast-milk fed infants had similar plasma concentrations of vitamin A (0.75 +/- 0.20 and 0.64 +/- 0.21 micromol/L, ns), 25-hydroxyvitamin D (34.4 +/- 25.6 and 47.5 +/- 26.7 nmol/L, ns) and vitamin E (9.5 +/- 3.2 and 8.4 +/- 3.3 micromol/L, ns). Vitamins A and E, and retinol binding-protein concentrations steadily increased with time in both groups of infants without attaining, at 3 months, values considered normal in term infants and in young children. At 3 months of age, concentrations of 25-hydroxyvitamin D reached values comparable to those observed in term infants. CONCLUSION: Plasma concentrations of vitamins A and E and of retinol binding-protein steadily increased during the the study without reaching full repletion values. At the conclusion of the study, the type of nutrition did not affect plasma vitamin concentrations.     

Intestinal absorption of vitamin E in low birth weight infants

Intestinal absorption of dl-alpha-tocopheryl acetate was studied in low birth weight infants. Vitamin E was given from the first day of life, either as a water-soluble (Ephynal) or as a lipid-soluble preparation (E-vitamin). Serum-alpha-tocopherol concentrations were determined before treatment and on days three and seven. Treatment with both vitamin E preparations increased serum-alpha-tocopherol on day three and seven. The mean serum-alpha-tocopherol +/- SD on day seven were 41.4 +/- 10.7 mumol/l for the Ephynal group and 26.7 +/- 12.5 mumol/l for the E-vitamin group, this difference being statistically significant (p less than 0.025). Oral feeding seems to influence the absorption of tocopherol from E-vitamin, as the infants with the highest serum-alpha-tocopherol concentrations were those with the highest oral/total feeding ratios. In infants with birth weight less than 1 000 g treatment with 25 mg Ephynal/day was found to increase serum-alpha-tocopherol on day seven to 46.9 +/- 12.3 mumol/l (mean +/- SD). This concentration is comparable to those reported by others using higher doses of oral vitamin E.     

Vitamin E and neonatal bilirubinemia.

A study was designed to determine the effect of vitamin E on bilirubinemia in the preterm infant. Twenty infants with birth weight between 1,000 and 1,500 gm and 20 infants with birth weights between 1,501 and 2,000 gm were studied. Half the infants in each birth weight group received vitamin E administered intramuscularly in a total dose of 50 mg/kg during days 1 to 3 of life; the remaining infants served as controls. The administration of vitamin E produced significantly increased plasma tocopherol concentrations and normal hydrogen peroxide hemolysis tests by the end of the first week of life. Infants with birthweights less than or equal to 1500 gm who received vitamin E demonstrated a significant decrease in serum bilirubin on day 3 of life (6.5 +/- 2.2 vs 8.8 +/- 2.2 mg/dl) as well as a significant decrease in peak serum bilirubin during the first week of life (8.3 +/- 2.2 vs 10.6 +/- 2.6 mg/dl). The duration of phototherapy also was significantly less in the vitamin E-supplemented group (48 +/- 18 vs 107 +/- 31 hours). These differences were less pronounced in infants with birth weights more than 1,500 gm.     

Vitamin D and mineral metabolism in the very low birth weight infant receiving 400 IU of vitamin D

STUDY OBJECTIVE: To examine (1) the effect of vitamin D intake (380 to 480 IU daily) on plasma 25-hydroxyvitamin D (25-OHD) and 1,25-dihydroxyvitamin D (1,25-(OH)2D) concentrations and (2) the relationship of 1,25-(OH)2D to calcium and phosphorus absorption and retention in the very low birth weight infant receiving a preterm infant formula. SUBJECTS: Eleven "well" infants with a birth weight and gestational age (mean +/- SD) of 1078 +/- 128 gm and 29 +/- 1.9 weeks, respectively, were studied for a 3-week period. Weight and postnatal age (mean +/- SD) at the beginning of the study were 1132 +/- 56 gm and 16 +/- 6 days, respectively. All infants were fed a preterm infant formula and tolerated a full enteral intake (120 kcal/kg/day) for the duration of the study. INTERVENTIONS: Plasma 25-OHD and 1,25-(OH)2D concentrations were measured at the beginning of the study and at the beginning of each 48-hour balance period. Calcium and phosphorus balance studies (n = 33) were performed weekly. MAIN RESULTS: Plasma 25-OHD (30 +/- 10 ng/ml) and 1,25-(OH)2D (54 +/- 14 pg/ml) concentrations were normal at the beginning of the study. Plasma 25-OHD values did not change, but 1,25-(OH)2D values increased (p less than 0.001) throughout the study. Plasma 1,25-(OH)2D concentrations were not related to calcium or phosphorus absorption and retention, but were a linear function of postconceptional age. CONCLUSIONS: Normal vitamin D status and activity are maintained in the very low birth weight infant fed a high calcium formula (380 to 480 IU of vitamin D daily). Plasma 1,25-(OH)2D concentrations are not related to calcium absorption but are linearly related to maturity.     

Effect of taurine supplementation on hepatic function during short-term parenteral nutrition in the premature infant

To evaluate the potential role of taurine deficiency in the pathogenesis of parenteral nutrition-induced cholestasis, 20 premature (less than 34 weeks AGA) infants were randomized to receive parenteral nutrition with and without taurine (10.8 mg/kg/day) during the first 10 days of life. Birth weight, gestational age, and protein and caloric intake were similar in both groups. Plasma taurine levels and hepatic function were assessed before the study began (3 +/- 1 days of age), at 5 +/- 1 days of age, and at 9 +/- 1 days of age. Although plasma taurine levels were significantly greater at 5 +/- 1 and 9 +/- 1 days of age (p = 0.009) in the group receiving supplementation, no differential effect on hepatocellular function could be detected during this short period of time. A decrease in plasma ammonia (p = 0.001), alanine aminotransferase (ALT) (p = 0.036), gamma-glutamyltranspeptidase (GGTP) (p = 0.05), 5'-nucleotidase (5'N) (p = 0.001), and bile salt concentrations was noted in both groups, indicating the rapid maturation of hepatic function even in the presence of parenteral nutrition during the first 10 days of life.