Diversity of Anopheles spp. (Diptera: Culicidae) in an Amazonian Urban Area

The genus Anopheles encompasses several species considered as vectors of human infecting Plasmodium. Environmental changes are responsible for behavior changes in these vectors and therefore the pattern of malaria transmission. To better understand the dynamics of malaria transmission, this study aimed at identify the species of adult anophelines found in a malaria endemic urban area of the Amazon region, Mâncio Lima, located in the Acre State Brazil. Using Shannon-type light traps installed at 11 collection points near fish ponds, a total of 116 anophelines were collected belonging to nine species. Anopheles darlingi Root 1926 and An. albitarsis s.l. Lynch-Arribalzaga 1878 were the most abundant and predominant species. Despite the low number of captured adult anophelines, the occurrence of An. darlingi throughout all urban area and the presence of secondary vectors reinforce the need of a permanent and continuous entomological surveillance.

Effects of season on boar semen parameters and antioxidant enzymes in the south subtropical region in Brazil

Although boar semen productivity is affected by seasonality, its effects are not equal among different regions which raise concerns regarding the profitability of boar stud farms. Therefore, the goals of this study were (i) to evaluate the seasonal effect on semen production in a commercial boar stud farm located in a subtropical climate region and (ii) to verify whether the activities of superoxide dismutase and glutathione peroxidase in spermatozoa and seminal plasma were associated with seminal traits of fresh and cooled semen. Nine boars were collected twice per season, and routine seminal parameter analyses were performed together with superoxide dismutase and glutathione peroxidase activities in seminal plasma and spermatozoa. Despite a reduction in sperm concentration in spring and summer, most seminal parameters were constant year-round. Temperature-humidity index was higher in the summer compared to spring, autumn and winter (p < .05). Superoxide dismutase activity in spermatozoa was increased in summer compared to autumn and winter (p < .05). The activities of both enzymes in seminal plasma and spermatozoa glutathione peroxidase remained unaltered throughout the seasons. In conclusion, seasonality showed little influence in overall boar seminal parameters despite microclimatic differences among seasons, and spermatozoa collected during summer increased superoxide dismutase activity.

Elemental distribution images in prostate samples by X-ray fluorescence microtomography

An X-ray transmission microtomography (CT) system combined with an X-ray fluorescence microtomography (XRFμCT) system was implemented in the Brazilian Synchrotron Light Laboratory (LNLS), in order to determine the elemental distribution in prostate samples aiming at establishing a correlation between the concentration of some elements and the characteristics and pathology of the tissues. The CT images were reconstructed using a filtered-back projection algorithm and the XRFμCT images were reconstructed using a filtered-back projection algorithm with absorption corrections.

Biological tissues analysis by XRF microtomography

The main of this work is to determine the elemental distribution in breast and prostate tissue samples in order to verify the concentration of some elements correlated with characteristics and pathology of each tissue observed by the X-ray transmission microtomography (microCT). The experiments were performed at the X-ray fluorescence beamline of the Brazilian Synchrotron Light Laboratory. The microCT images were reconstructed using a filtered-back-projection algorithm and the XRF microtomographies were reconstructed using a filtered-back-projection algorithm with absorption corrections.

[Chagas' disease in a urban population of the health district of Rio Verde, Mato Grosso do Sul State, Brazil]

In order to evaluate some aspects of the Chagas' disease on urban population of the 12 municipalities of the sanitarian district of Rio Verde, Mato Grosso do Sul state, on 1998 we carried out a serological survey investigating anti-T. cruzi IgG by indirect immunofluorescence on blood samples collected on filter paper of 14,709 resident persons, confirmed by indirect hemagglutination and ELISA in serum. The parasitaemia was evaluated by indirect xenodiagnosis on 134 chagasic patients and the morbidity evaluated by anamnesis, physical exam and electrocardiogram in 191 pairs of chagasic/non-chagasic patients. The seropositivity was 1.83% (0.93% in autochtonous, 5.01% in alochtonous), xenodiagnosis was positive in 17.2% of the individuals (12.3% in autochtonous, 20.8% in alochtonous) and 24.6% of the seropositive patients presented chronic chagasic cardiopathy (19.1% in autochtonous, 27.8 in alochtonous). The analysis of the dates showed that alochtonous population is the main responsible for presence of the infection and morbidity of Chagas disease in the studied area.

Necrotizing enterocolitis in neonates with congenital heart disease: risk factors and outcomes

OBJECTIVE

Necrotizing enterocolitis (NEC) is primarily a disease of the premature infant. Among children born at term, however, congenital heart disease may be an important predisposing factor for this condition. To determine risk factors for NEC in patients with congenital heart disease, we conducted a case-control study of neonates with cardiac disease admitted to the cardiac intensive care unit at our center during the 4-year period from January 1995 to December 1998.

METHODS

Cardiac diagnosis and age at admission were analyzed for association with NEC among the 643-patient inception cohort. Demographic, preoperative, and operative variables were recorded retrospectively in 21 neonates with congenital heart disease who developed NEC and 70 control neonates matched by diagnosis and age at admission. Using parametric and nonparametric analysis, cases and controls were compared with respect to previously identified risk factors for NEC.

RESULTS

Among the entire cohort of 643 neonates with heart disease admitted to the cardiac intensive care unit, diagnoses of hypoplastic left heart syndrome (odds ratio [OR] = 3.8 [1.6-9.1]) and truncus arteriosus or aortopulmonary window (OR = 6.3 [1.7-23.6]) were independently associated with development of NEC by multivariable analysis. In the case-control analysis, earlier gestational age at birth (36.7 +/- 2. 7 weeks vs 38.1 +/- 2.3 weeks), prematurity (OR = 3.9 [1.2-12.5]), highest dose of prostaglandin >0.05 microg/kg/minute (OR = 3.9 [1. 2-12.5]), and episodes of low cardiac output (meeting specific laboratory criteria) or clinical shock (OR = 6.5 [1.8-23.5]) correlated with the development of NEC. Earlier gestational age and episodes of low output were the only factors that remained significantly associated with NEC by multivariable analysis. Although there was no difference in hospital mortality between patients with and without NEC, mean hospital stay was significantly longer in those who developed NEC (36 +/- 22 days vs 19 +/- 14 days).

CONCLUSIONS

The risk of NEC in neonates with congenital heart disease is substantial. Factors associated with an elevated risk of NEC in infants with heart disease include premature birth, hypoplastic left heart syndrome, truncus arteriosus, and episodes of poor systemic perfusion or shock. Heightened suspicion is warranted in newborns with these risk factors.

Effects of sweet taste stimulation on growth and sucking in preterm infants

OBJECTIVE

To evaluate the effect of sweet taste stimulation in augmenting the reported growth-enhancing effects of nonnutritive sucking in preterm infants who are gavage-fed.

DESIGN

Random assignment of preterm infants to receive stimulation by one of three methods during each feeding until totally orally fed.

SETTING

Hospital intensive-care and infant transitional units.

PATIENTS

Eligibility criteria included body weight greater than or equal to 1,250 g, gestational age younger than 34 weeks, growth parameters appropriate for gestational age, tolerating at least 100 kcals/kg/day by gavage feeding with evidence of weight gain, and no clinical evidence of health complications. Data are presented for 42 infants who completed 14 days of treatment.

INTERVENTIONS

Exposure to a sweet pacifier, a latex pacifier, or maternal heartbeat sounds during gavage feedings.

MAIN OUTCOME MEASURES

Growth, time to total oral feeding, and sucking responses.

RESULTS

No significant differences in sucking measures were noted among treatment groups. Differences in progression time to total oral feedings and weight gain favored the sweet-pacifier group but were not statistically significant.

CONCLUSIONS

Oral stimulation of gavage-fed, preterm infants during a 2-week hospitalization was not sufficient to elicit a significant improvement in growth efficiency, progression to total oral feedings, or sucking maturation. Additional studies may show a beneficial effect of chemosensory stimulation in preterm infants.

Nutritional care of the extremely premature infant

In summary, the nutritional care of extremely premature babies includes special attention to glucose homeostasis and fluid and electrolyte balance in the immediate postnatal period. Parenteral nutrition should be started routinely on the 2nd or 3rd day of life, if the infant is metabolically stable, and continued until the infant is receiving sufficient enteral feedings to promote growth. If not clinically contraindicated, minimal enteral feedings should be started before the end of the first week of life. The decision to either advance or maintain minimal enteral feedings at a constant level should take into account the clinical status of the infant. Fortified preterm human milk is the preferred feeding and premature infant formulas, the best substitute. Multivitamin supplements may be necessary, depending on formula intake. Iron supplements can be initiated as early as 2 weeks of age and high levels of intake appear to be necessary during erythropoietin therapy.

Use of high-fat formula for premature infants with bronchopulmonary dysplasia: metabolic, pulmonary, and nutritional studies

The use of dietary fat in preference to carbohydrate offers the theoretic advantage of diminishing carbon dioxide production and thus the respiratory quotient, which may be beneficial for babies with chronic lung disease. Ten premature infants (birth weight (mean +/- SEM), 1.13 +/- 0.12 kg; postnatal age, 9 +/- 1 weeks) with bronchopulmonary dysplasia were alternately fed a high-fat and a high-carbohydrate formula each for 1 week, in randomized order. Lower rates of carbon dioxide production (6.6 +/- 0.3 versus 7.4 +/- 0.4 ml/kg per minute; p < 0.05), and consequently lower respiratory quotients (0.80 +/- 0.02 versus 0.94 +/- 0.01 ml/kg per minute; p < 0.005), were observed during the administration of the high-fat formula. There were no significant differences in results of pulmonary function tests with the use of either formula. Both formulas were equally well tolerated and able to promote adequate growth and normal biochemical profiles. However, weight gain was significantly greater with the administration of the high-carbohydrate formula, possibly because of an increase in the accretion of body fat. We conclude that the short-term use of high-fat formula for infants with bronchopulmonary dysplasia decreases carbon dioxide production while maintaining adequate growth and nutritional status.

Enteral theophylline and necrotizing enterocolitis in the low-birthweight infant

In a two-phased retrospective study, clinical factors associated with the development of necrotizing enterocolitis (NEC) in neonates were identified. The first phase found 13 infants with NEC who had been treated more frequently with enteral theophylline (P < .025) and fed higher volumes (> 150 mL/kg/day; P < .05) than controls of comparable birthweight and postnatal age. Seven of the 13 infants with NEC, weighing < 1,250 g at birth, had previously received intravenous aminophylline and been changed to enteral theophylline within six days before the onset of NEC. Prolonged rupture of membranes was more prevalent (P < .025) in infants with birthweight > 1,250 g who developed NEC in the first week of life. Maternal preeclampsia helped protect against the development of NEC (P < .05). In the second study phase, 59 infants with birthweights < 1,250 g were evaluated for gastrointestinal disturbance within five days of the introduction of any enteral medication. The frequencies of NEC, NEC scare, and feeding intolerance were greater in infants treated with enteral theophylline than in those treated with all other enteral medications combined (P < .05). This two-phased study confirms the multifactorial etiology of NEC and indicates that the administration of enteral theophylline to young infants < 1,250 g may be a predisposing factor to GI disturbances and NEC. These findings warrant a further prospective investigation.

Association of maternal lithium exposure and premature delivery

Lithium is widely used and the treatment of choice for patients with manic-depressive illness. For pregnant patients with manic-depressive illness, however, the use of lithium during the first trimester of pregnancy may present an increased risk for fetal maldevelopment. We have recently cared for several large-for-gestational-age, prematurely born infants whose mothers were treated with lithium throughout pregnancy. To determine whether maternal lithium use during pregnancy may predispose to the onset of premature labor and fetal macrosomia, we reviewed records from the International Register of Lithium Babies and from a cohort of manic-depressive pregnant women. More than one third (36%) of infants reported to the International Register were born prematurely, and 37% of the premature infants were large for gestational age; 15% of the term infants were born large for gestational age. In the cohort group, manic-depressive mothers who received lithium during pregnancy had a 2.5-fold higher incidence of premature births than manic-depressive pregnant patients who did not receive lithium treatment. The incidence of large-for-gestational-age births in lithium-treated women in the cohort was not different from that of the general population or from manic-depressive women not treated with lithium. In summary, an association between maternal lithium therapy and premature delivery is reported. We recommend that women receiving lithium therapy during pregnancy be closely monitored for the onset of premature labor.

Umbilical vs peripheral vein catheterization for parenteral nutrition in sick premature neonates

The efficacy and safety of using umbilical venous catheters vs. peripheral venous catheters for the delivery of parenteral nutrition was studied in 129 critically ill premature infants who were treated in a neonatal intensive care unit for the first 3 weeks of life. Infants who received parenteral nutrition by umbilical venous catheter had greater parenteral caloric intake, lower physiologic weight loss and greater weight gain during the study as compared to infants who received parenteral nutrition by peripheral vein. While the overall incidence of sepsis was comparable in both groups (19% vs 19.7%), benign and transient episodes of hyperglycemia were seen more commonly in infants receiving parenteral nutrition by umbilical catheters. None of the hyperglycemic infants, however, required insulin therapy. The incidence of other metabolic complication was comparable in both groups. At follow up, no evidence of portal hypertension was detected in any of the infants up to 66 months of age treated with umbilical venous catheters. We conclude that the use of umbilical venous catheter allows for a comparably safe and a more appropriate parenteral nutrition support than peripheral catheters in critically ill premature neonates.

Lecithin:cholesterol acyltransferase (LCAT) activity during lipid infusion in premature infants

Plasma cholesterol and lecithin concentrations are regulated by the serum enzyme lecithin: cholesterol acyltransferase (LCAT). LCAT activity is low in cord blood of premature infants, suggesting that in these infants the hypercholesterolemia associated with Intralipid infusion might be due to low LCAT activity. The serum LCAT activity has not been quantitated in preterm infants receiving intravenous fat emulsions. We have therefore quantitated LCAT activity in eleven premature infants maintained on total parenteral nutrition (TPN). Ten infants were studied during the first 2 weeks after birth; they received daily infusions of Intralipid at a rate of 0.5-2.0 g/kg/day over 15 h. One infant received 3.8 g/kg/day during the second week. In addition to LCAT, serum apoprotein A1 (the cofactor of LCAT), cholesterol, triglycerides, and free fatty acids were quantitated. Blood specimens were taken before the start of the infusion and 15-45 min before its completion. The LCAT activity and apoprotein A1 concentrations remained, respectively, 21-24% and 30-35% of adult levels. However, serum cholesterol levels remained in the normal range during the fat infusion. It remains to be established whether low LCAT activity and apoprotein A1 levels are due to the administration of Intralipid (which lowers LCAT activity in rats), to the lack of enteral feedings, or to prematurity per se. Our data suggest that administration of Intralipid at a rate not exceeding 1-2 g/kg/day does not impair the clearing of Intralipid-lecithin and the metabolism of cholesterol.

Serum myoinositol concentrations in premature infants fed human milk, formula for infants, and parenteral nutrition

Myoinositol concentration was studied in serum of 65 neonates and their mothers at the time of birth, in samples of various types of feedings for infants, and in serial serum samples of 15 premature infants receiving human milk, formulas for infants, or parenteral nutrition over a 3-wk period. At birth the serum concentration of myoinositol was greater in neonates than in their mothers (108 +/- 10 vs 52 +/- 6 mumol/L, respectively, means +/- SEM, p less than 0.01). In feedings for infants, the concentrations of myoinositol were significantly greater in human milk than in formulas or parenteral nutrition solutions (1840 +/- 451 vs 420 +/- 110 vs 100 +/- 8 mumol/L, respectively, p less than 0.001). Over a 3-wk period the serum concentration of myoinositol increased in infants receiving human milk but not in those receiving formulas or parenteral nutrition. Serum concentrations of myoinositol in neonates are greater than in adults and are directly influenced by myoinositol intake.

Effect of fat infusions on platelet concentration in premature infants

Critically ill premature infants often require lipid emulsions with parenteral nutrition until enteral feedings can be safely initiated. Because thrombocytopenia has been listed as a potential side effect of fat emulsions, we examined the effect of varying doses of intravenous fat infusions on platelet concentrations in premature infants. An initial validation study demonstrated no artifactual effect of fat infusions on the electronic cell counter method of platelet enumeration. We observed no adverse effect of fat emulsions administered at doses of 0.8 to 3.3 g/kg/day on platelet concentration either during short-term (48 hr) or long-term study periods (4 weeks).

Nutritional care of the surgical neonate

The surgical neonate is at great risk of developing nutritional deficiencies. However, recent advances in nutritional support, including the development of special elemental diets, infant formulas, nutritional supplements and more suitable additives for parenteral nutrition, have allowed health professionals effectively to prevent the occurrence of malnutrition in sick neonates. Strict monitoring of dietary intake, growth velocity, and biochemical parameters are essential while providing nutritional support. The complication of parenteral nutrition can be reduced by following standard recommendations for preparing solutions, caring for the central and the peripheral catheters, and biochemically monitoring the infant. The organization of a hospital nutrition support service composed of physicians, nurses, nutritionists, and pharmacists is essential in establishing guidelines for the safe delivery of nutritional therapy and in educating hospital personnel and parents on how to best meet the nutritional needs of the surgical neonate.

A comparison of the mid-arm circumference/head circumference ratio and ponderal index for the evaluation of newborn infants after abnormal intrauterine growth

We studied the accuracy of the ponderal index and the mid-arm circumference/head circumference ratio for detecting newborn infants who were likely to be symptomatic because of aberrant intrauterine growth. Sixty infants were evaluated because of suspected intrauterine growth retardation; both the mean ponderal index and mid-arm circumference/head circumference ratio were significantly lower in the group of 30 symptomatic infants than in the group of 30 asymptomatic infants (p less than 0.05). However, the mid-arm circumference/head circumference ratio identified a significantly higher percentage of the symptomatic infants than the ponderal index (80% vs. 47%; p = 0.007). An additional 60 infants were evaluated because of suspected abnormal intrauterine growth acceleration. The mean mid-arm circumference/head circumference ratio, but not the ponderal index, was significantly higher in the group of 30 symptomatic infants than in the group of 30 asymptomatic infants (p less than 0.005). Again, the mid-arm circumference/head circumference ratio identified a significantly higher percentage of the symptomatic infants than the ponderal index (79% vs. 33%; p less than 0.001). The mid-arm circumference/head circumference ratio is more accurate than the ponderal index for the evaluation of potentially symptomatic newborn infants who suffered abnormal fetal growth. The ponderal index is not useful for the detection of symptomatic large-for-dates infants.

Effect of heparin dose and infusion rate on lipid clearance and bilirubin binding in premature infants receiving intravenous fat emulsions

The effect of heparin dose and infusion rate on plasma lipids, lipases, and unbound bilirubin was investigated in 22 premature infants with physiologic jaundice. Infants were randomly assigned to receive low or high intravenous doses (24 vs 137.3 U/day) of heparin. Each patient then received 2 g/kg/day of 10% Intralipid on 2 successive days: one day during a 15-hour period and the other day over 24 hours, with the order assigned randomly. The results demonstrate a significantly greater change in serum-free fatty acids in infants receiving the high heparin dose during the 15-hour lipid infusion period. Lipoprotein lipase activity rose more with the high heparin dose and equally at either infusion rate. We conclude that lipid infusions of 2 g/kg/day with low heparin dosage infused over 24 hours resulted in less elevation in serum-free fatty acids. There were no adverse effects on unbound bilirubin at either infusion rate or heparin dosage.

Serum transthyretin levels and protein intake as predictors of weight gain velocity in premature infants

Nutritional intakes, transthyretin (prealbumin) levels, and anthropometric measurements were measured weekly in 26 preterm infants from week 2 of life throughout hospitalization. A sustained significant increase in protein intake occurred in 14 infants over a 2-week period. When mean protein intake increased, mean transthyretin levels increased during the same week (p less than 0.001), followed 1 week later by significant increases in mean weight, occipitofrontal head circumference (OFC), and mid-arm circumference (MAC). In the other 12 infants, a sustained significant decrease in protein intake occurred over 2 weeks. When mean protein intake decreased (p less than 0.01), transthyretin levels decreased during the same week (p less than 0.05), followed 1 week later by significant decreases in mean weight and MAC growth. Over all hospitalization weeks (n = 95), rates of weight gain were more significantly associated with previous trends in transthyretin levels (p = 0.007) than with protein intake alone (p = 0.08). In particular, declines in rates of weight gain were predicted significantly more frequently by the prior week's transthyretin trend (70%) than by the trend in protein intake (47%). In growing premature infants, changes in transthyretin levels occur 1 week before changes in anthropometric measurements. Changes in transthyretin levels are more predictive than changes in protein intake alone for monitoring growth velocity in preterm infants.

Total parenteral nutrition with intralipid in premature infants receiving TPN with heparin: effect on plasma lipolytic enzymes, lipids, and glucose

Plasma lipolytic activity (lipoprotein lipase and hepatic lipase), free fatty acids (FFA), triglycerides, cholesterol, and glucose levels were measured in 21 premature infants [gestational age 26-37 weeks (mean +/- SEM 30.4 +/- 0.63 weeks), aged 1-8 days (mean +/- SEM 3.00 +/- 0.35 days)]. All infants were maintained on total parenteral nutrition with heparin (1 U/ml) and were given Intralipid, 1, 2, and 3 g/kg/day, over 15 h on days 1, 2, and 3, respectively. Blood samples were drawn before and at the end of Intralipid administration. Baseline plasma lipolytic activity, before the start of lipid infusion, was 1.54 +/- 0.24 U/ml (1 U = 1 mumol [3H]oleic acid released from tri[3H]olein/h). Lipolytic activity increased after lipid infusion to 4.04 +/- 0.96, 4.32 +/- 0.63, and 6.09 +/- 1.00 U/ml on days 1, 2, and 3 of the study. Hepatic lipase amounted to 38-47% of total lipolytic activity. During the 3 days of lipid infusion, there were dose-dependent increases in plasma FFA, triglyceride, and cholesterol. Whereas FFA and triglyceride concentrations returned to prelipid infusion levels 9 h after stopping the infusion of Intralipid, 1, 2, or 3 g/kg, there was a cumulative increase in plasma cholesterol and glucose concentrations. The close correlation between FFA concentrations and plasma lipolytic activity (r = 0.655, p less than 0.001) suggests considerable intravascular lipolysis. The positive correlation between plasma FFA and triglycerides (r = 0.632, p less than 0.001) and FFA and cholesterol (r = 0.582, p less than 0.001) indicate, however, that intravascular lipolysis does not prevent the lipemia associated with Intralipid infusion to low birth weight infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Mid-arm circumference and mid-arm/head circumference ratios: standard curves for anthropometric assessment of neonatal nutritional status

Two hundred four neonates, 25 to 42 weeks estimated gestational age (EGA), were measured on day 2 or 3 of life for upper mid-arm circumference (MAC) and head circumference. Regression analysis was used to construct standard curves for MAC versus EGA and mid-arm circumference/head circumference ratio (MAC/HC) versus EGA. Correlation coefficients were 0.93 for MAC versus EGA, and 0.84 for MAC/HC versus EGA. MAC, MAC/HC, and head circumference were also highly correlated with birth weight. These measurements may more accurately assess intrauterine growth and body proportionality at birth than weight, length, and head circumference.

Mid-arm circumference/head circumference ratios for identification of symptomatic LGA, AGA, and SGA newborn infants

Mid-arm circumference/head circumference ratios (MAC/HC) and birth weights obtained in 73 neonates were studied to compare which of these growth measurements could more accurately predict risk of metabolic complications resulting from either acceleration or retardation of fetal growth. The MAC/HC ratio was more sensitive than birth weight in distinguishing symptomatic large for gestational age (LGA) infants who were born to diabetic mothers from other LGA infants who were asymptomatic, and symptomatic from asymptomatic small for gestational age infants. In addition, the MAC/HC ratio identified symptomatic appropriate for gestational age (AGA) infants born to diabetic mothers and AGA infants with signs and symptoms of growth retardation. The MAC/HC is more useful than birth weight in assessing newborn infants at risk for the metabolic complications associated with fetal growth disorders.

Cord prealbumin values in newborn infants: effect of prenatal steroids, pulmonary maturity, and size for dates

We assessed cord prealbumin concentrations in 214 appropriate for gestational age newborn infants, 21 small for gestational age infants, and 27 large for gestational age infants to establish normal values and to assess the effect of intrauterine growth, prenatal steroids, and pulmonary maturity on prealbumin levels. Cord prealbumin values were significantly correlated with increasing gestational age (r = 0.33; P less than 0.001) and birth weight (r = 0.40, P less than 0.001) in the AGA neonates. Neonates born before 37 weeks gestation had significantly lower prealbumin levels than those born at term (P less than 0.001). The SGA infants had significantly lower levels than age-matched AGA controls (P less than 0.01), and LGA infants had significantly higher levels than age-matched AGA controls (P less than 0.001). In preterm infants, those with exposure to prenatal steroids (betamethasone or premature rupture of membranes) had significantly higher prealbumin values than control infants of comparable age and weight (P less than 0.001). Infants without respiratory distress syndrome had higher levels than those of comparable age and weight with hyaline membrane disease (P less than 0.05). This study demonstrates that a correlation of gestational age and birth weight exists with cord prealbumin levels, and that the large variability at each gestational age may be accounted for in part by appropriateness of size for dates, prenatal steroid exposure, and pulmonary maturity.

Nutritional deficiencies in the neonate

This article reviews common nutritional deficiencies that have been identified in newborn infants, including deficiencies of protein; vitamins A, D, K, C, and E; calcium and phosphorus; folate; zinc; and copper. The etiology, clinical presentation, diagnosis, and treatment of these nutritional deficiencies are discussed.

Controversies in neonatal nutrition

The assessment of growth parameters remains one of the most practical and valuable tools to estimate nutritional status in neonates. Growth assessment in full-term infants is performed by using charts developed by the National Center for Health and Statistics. The assessment of post-natal growth in premature infants is controversial and can be performed by using either intrauterine or extrauterine standards. The selection of appropriate growth charts should be based on clinical, demographic, ethnic, and socioeconomic similarities of the population used for reference. Daily energy intakes ranging from 100 to 120 kcal/kg/day have been recommended for full-term infants, while higher intakes ranging from 114 to 181 kcal/kg/day have been recommended for premature neonates. Full-term infants should be nursed or nipple fed on demand; however, premature infants should ideally be tube fed by intermittent gastric feeding (gavage). Continuous gastric and transpyloric feedings are indicated in selected infants. Human milk is a preferred food for full-term infants during the first six months of life; however, this precept does not suggest that all infants who are exclusively breast-fed will grow adequately. Preterm human milk is also a preferred food for the low birthweight infant, provided nutritional supplements are used. It is unclear whether the supplementation of vitamin D, iron, and fluoride in full-term breast-fed infants should be started at birth, at the time of initiation of solid foods, or at the age of six months. The routine supplementation of multivitamins, folic acid, and vitamin E to all low birthweight infants is controversial. Most investigators suggest vitamin supplementation be given until the intake of formula or breast milk is sufficient to meet daily requirements. Vitamin E appears to exert a protective effect in premature infants against the development of severe retinopathy. The supplementation of vitamin E should be dependent upon the serum vitamin E concentration. It is controversial whether iron supplementation for premature infants should be initiated soon after birth or at two months of age, or whether higher doses of iron should be given to very low birthweight infants. If iron supplementation is started at birth, vitamin E status should be closely monitored. Although the optimal intakes of calcium and phosphorus in infant feedings have not been firmly established, the levels of calcium and phosphorus in human milk appear to be inadequate for the growing low birthweight infant.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of gestational age upon prealbumin and retinol binding protein in preterm and term infants

The relationships between maternal and umbilical cord levels of prealbumin and retinol binding protein (RBP) were studied in 68 mothers and in their appropriate-for-gestational-age neonates delivered between 25 and 42 weeks gestation. Arterial and venous concentrations of prealbumin and RBP in cord sera were also studied in a subsample of eight infants. In cord sera, prealbumin and RBP levels increased with gestational age (prealbumin, r = 0.47; RBP, r = 0.40, p less than 0.01), and were significantly different in neonates born at term compared to those born prematurely (mean +/- SD, prealbumin 12.0 +/- 3.9 mg/dl vs. 8.8 +/- 2.3 mg/dl, p less than 0.001; RBP, 2.3 +/- 0.8 vs. 1.8 +/- 0.5 mg/dl, p less than 0.005). No significant differences between arterial and venous concentrations of prealbumin and RBP were observed in cord blood. In maternal blood, serum prealbumin and RBP concentrations did not increase with length of gestation (25-42 weeks). Maternal prealbumin was not correlated significantly with infants' cord serum levels; the correlation coefficient for RBP was 0.29, p less than 0.05. Maternal prealbumin and RBP serum levels were approximately twice the values seen in neonates born both at term and prematurely. Although the difference between premature and full-term cord levels of prealbumin and RBP may reflect an increase in hepatic protein synthesis that occurs with maturation of the fetus and/or a change in placental function after 37 weeks gestation, neither of these factors sufficiently explains the variance in neonatal prealbumin and RBP levels.

Effect of neonatal caloric deprivation on head growth and 1-year developmental status in preterm infants

The effects of neonatal illness and caloric intake on head growth velocity and on 1-year developmental outcome were studied in 73 appropriate (AGA) and small for gestational age (SGA) premature infants of (mean +/- SD) 30 +/- 2 weeks gestation who received intensive care during the neonatal period. Head growth from birth to 1 year of corrected age was characterized by a triphasic curve initiated by a period of growth arrest or suboptimal growth followed by a period of catch-up growth and terminated by a period of growth along standard curves. Head growth arrest or suboptimal head growth were directly related to the duration of the initial period of caloric deprivation (less than 85 kcal/kg/day) and to the duration of mechanical ventilation. Catch-up head growth was influenced by the duration of the preceding period of caloric deprivation in all infants and by the caloric intake during that phase only in SGA infants; catch-up growth was unrelated to the duration of mechanical ventilation. Head growth along standard curves occurred in all infants by 3 months of corrected age and persisted up to 1 year of corrected age. Infants calorically deprived the longest (AGA 4 to 6 weeks, SGA 2 to 3 weeks) had head growth along standards at curves below -1 SD on the growth chart; all other groups had this phase of head growth at curves between the mean and -1 SD. Infants calorically deprived for more than 4 weeks had developmental scores below normal ranges by 1 year of corrected age.

The effect of 15-hour fat infusions of varying dosage on bilirubin binding to albumin

Intravenous fat emulsions (1, 2, and 3 g/kg) were administered over 15 hr to 20 appropriate for gestational age premature infants with physiologic hyperbilirubinemia to determine the effect of fat infusions on the serum free fatty acid:albumin molar ratio (F/A) and on unbound bilirubin. Significant increases (p less than 0.05) in F/A occurred with each increase in lipid dose in infants less than 30 wk gestation, but not in infants greater than or equal to 30 wk gestation. There was a direct linear correlation (r = 0.65, p less than 0.001) between F/A ratio and unbound bilirubin (estimated fluorometrically by the ratio of albumin-bound bilirubin/reserve bilirubin binding capacity, B/R). The largest increases in unbound bilirubin (albumin-bound bilirubin/reserve bilirubin binding capacity) were seen in infants with F/A greater than 4.0. The gestational age of infants with F/A greater than 4.0 was significantly less (p less than 0.01) than infants with F/A less than 4.0 (28.7 +/- 0.47 vs. 31.1 +/- 0.40 wk, mean +/- SEM). In 10/58 infusions there was a fall in unbound bilirubin, unrelated to birthweight, gestational age, postnatal age, however, during these infusions the end-infusion F/A was greater than or equal to 3.0. We conclude that 1 g/kg of lipid emulsion infused over a 15-hr period has minimal risk of decreasing bilirubin binding in premature infants less than 30 wk gestation. As doses of 2 or 3 g/kg are used, these infants may be at risk of decreased bilirubin binding, due to elevations in the F/A ratio. Monitoring of the F/A ratio may identify infants at risk for decreased bilirubin binding during lipid infusion and provide guidelines for determining the appropriate lipid dose.

Heart rate and sleep time: their relationship with growth and adiposity in male infants

In a clinical trial based on the direct relationship between heart rate activity and energy expenditure during awake and asleep states, 21 healthy 18-month-old infants had their heart rate monitored over a period of 24 h and correlated with their nutritional intake, growth parameters, and measurements of adiposity (fat cell size and skinfold thickness). Infants with higher 24-h and asleep heart rates had smaller fat cells (r = -0.50) and skinfold thickness (abdominal r = -0.70, suprailiac r = -0.80, triceps r = -0.67). Infants with higher relative weight had higher heart rates during awake periods (r = 0.60). Infants sleeping for longer periods had higher weight gain velocity from birth (r = 0.51) and higher relative weight (r = 0.54). This study demonstrates the heart rate activity and duration of sleep are related to growth and adipose tissue deposition during infancy.

Taurine deficiency in the severe hepatic dysfunction complicating total parenteral nutrition

The etiology of the severe hepatic dysfunction associated with total parenteral nutrition (TPN) remains unknown, but recent studies suggest that taurine deficiency may be associated with the development of cholestasis in experimental animals. That taurine deficiency might also play a role in the development of the severe hepatic dysfunction in human infants receiving TPN as their sole nutritional intake is the subject of the present report. Serial plasma aminograms were obtained from three children with severe hepatic dysfunction associated with TPN, in whom progressive disease led to death after 20, 13, and 14 months. All three children underwent massive intestinal resection for necrotizing enterocolitis, leaving 30, 44, and 17 cm of viable small bowel, respectively. Balanced TPN was given as 20 to 25 g/kg/d dextrose, 1.5 to 2.5 g/kg/d crystalline amino acids, and 2 to 3 g/kg/d fat emulsion; enteral feedings were attempted but were poorly tolerated. Mild cholestasis progressed to severe hepatic dysfunction manifested by hyperbilirubinemia, increased serum transaminases, hypoproteinemia, and abnormal coagulation profiles. Liver histology revealed extensive fibrosis, fatty replacement, and coarse cholestasis, necrosis not being prominent. Serial plasma aminograms revealed markedly elevated plasma levels of methionine (1353, 1168, and 113 nm/mL), low levels of 1/2 cystine (68.4, trace, and 17 nm/dL), and undetectable levels of taurine; plasma levels of branched-chain amino acids were normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term assessment of growth, nutritional status, and gastrointestinal function in survivors of necrotizing enterocolitis

The long-term effect of necrotizing enterocolitis on growth, nutritional status, and gastrointestinal function was assessed in premature infants at the age of 1 year. Of the 22 of 40 infants who developed NEC, 18 were given medical treatment and four required surgical treatment consisting of intestinal resection of less than one fourth of the small bowel. Eighteen infants who did not develop NEC served as controls. At 1 year follow-up, NEC survivors and controls had normal and comparable anthropometric measurements, biochemical values (serum iron, albumin, prealbumin, retinol binding protein, liver function studies) and gastrointestinal tract function (vitamin E absorption, fasting serum bile acids concentration, lactose breath test). This study demonstrates that, in the absence of short bowel syndrome, there is no detectable long-term effect on growth, nutritional status, and gastrointestinal tract function in premature infants who had NEC in the newborn period.

Nonnutritive sucking during gavage feeding enhances growth and maturation in premature infants

The effects of nonnutritive sucking (NNS) by means of a pacifier during gavage feeding were studied in 30 premature infants whose birth weight was less than 1,500 g. The addition of NNS accelerated the maturation of the sucking reflex, facilitating a more rapid transition from gavage to oral feedings. Additionally, NNS decreased intestinal transit time and caused a more rapid weight gain despite comparable caloric intake resulting in a shortened hospital stay. Although the physiologic mechanisms resulting from this form of oral stimulation remain to be investigated, our data suggest that NNS may be an important factor to consider in the feeding of premature infants.

Sustained flexibility in infant feeding tubes containing nonmigrating plasticizer

Due to medical complications related to stiffness developed in polyvinyl chloride (PVC) feeding tubes presently manufactured with di-octylphthalate (DOP), we have assessed the flexibility of PVC tubes manufactured with a nonmigrating plasticizer, ti-octyltrimellitate (TOTM) (National Catheter Co., Argyle, NY). Two sizes of DOP and TOTM PVC feedings tubes were evaluated, #5 French and #8 French. Number 5 French DOP tubes became significantly stiffer as early as 1 to 2 days after intubation and continued to stiffen up to 8 days of use. Among the #5 French DOP tubes, those placed in the jejunum were found to become significantly stiffer than those placed in the stomach. No correlations were found between the development of stiffness and gestational age, postnatal age, sex, birthweight, or kinds of feedings. In contrast, #5 French TOTM and #8 French tubes (DOP and TOTM) did not develop any significant stiffness up to 5 to 8 days of use. This study demonstrates the sustained flexibility of TOTM tubes, and important factor to increase the safety of enteral feedings in newborn infants.

Hyperalimentation-induced cholestasis. Increased incidence and severity in premature infants

Two hundren sixty-seven neonates who received parenteral nutrition were monitored for signs of liver dysfunction. Cholestatic jaundice occurred in we infants, with a higher incidence in the more immature infants. There was an inverse correlation between severity of jaundice and the degree of prematurity. Infants with cholestasis remained without gastrointestinal feedings and received parenteral nutrition for periods of time significantly higher than infants without cholestasis. The incidence of this complication did not seem to correlate with the amount of protein infusate (amino acid solution). A higher incidence of sepsis was noted in infants who were affected by cholestasis. Close monitoring for signs of liver dysfunction in all neonates receiving parenteral nutrition is strongly recommended.

Controlled study of transpyloric and intermittent gavage feeding in the small preterm infant

There were 53 appropriate for gestational age infants with a birth weight of less than 1,700 gm admitted to the Children's Hospital in Denver who were randomly assigned to two groups for gavage or transpyloric (nasojejunal) feedings. The two groups were not significantly different in terms of gestational age, birth weight, and morbidity. No significant differences were observed for caloric intake after 4 days of age, growth parameters (weight, length, and head circumference), serum total protein levels, feeding-related complications, duration of intravenous fluid supplementation, and length of hospitalization. The results indicate that intermittent gastric gavage feedings are as efficacious as transpyloric feedings in supplying nutrition to the low birth-weight infant. Because of inherently greater risks, costs, radiation, and requisite personnel expertise, transpyloric feedings cannot be recommended as a routine method of feeding for the low birth-weight infant.

A clinical score for predicting the level of respiratory care in infants with respiratory distress syndrome

A scoring system was developed to predict the need for transferring infants with respiratory distress syndrome (RDS) from community hospitals to specialized respiratory care centers. Five clinical and laboratory determinations (birthweight, clinical RDS score, FI02, PCO2 and pH) recorded from 100 infants with RDS during one year were utilized in a score with values ranging from 0 to 10. Application of the score to 159 infants with RDS during the following year showed that: (1) 73 per cent of infants scoring less than or equal to 3 received only oxygen by hood; (2) 75 per cent of infants scoring 4--5 required continuous positive airway pressure (CPAP); and (3) 87 per cent of infants scoring greater than or equal to 6 needed mechanical ventilation (7V). Mean scores were significantly different (p less than 0.02) for each type of respiratory therapy employed: oxygen by hood (2.30 +/- 0.19 S.E.M.); CPAP (4.27 +/- 0.16 S.E.M.); MV (6.72 +/- 0.25 S.E.M.). The accuracy and simplicity of the score make it valuable for the physician in the community hospital to assist in deciding when to transfer a neonate with RDS for more intensive respiratory therapy.