Dopamine versus dobutamine in very low birthweight infants: endocrine effects

OBJECTIVES: To compare the endocrine effects of dopamine and dobutamine in hypotensive very low birthweight (VLBW) infants. DESIGN: Non-blinded randomised prospective trial. SETTING: Level III neonatal intensive care unit. PATIENTS: 35 hypotensive VLBW infants who did not respond to volume loading, assigned to receive dopamine or dobutamine. Measurements: Haemodynamic variables and serum levels of thyroid stimulating hormone (TSH), total thyroxine (T(4)), prolactin (PRL) and growth hormone were assessed during the first 72 h of treatment and the first 72 h after stopping treatment. RESULTS: Demographic and clinical data did not significantly differ between the two groups. Necessary cumulative and mean drug doses and maximum infusion required to normalise blood pressure were significantly higher in the dobutamine than in the dopamine group (p<0.01). Suppression of TSH, T(4) and PRL was observed in dopamine-treated newborns from 12 h of treatment onwards, whereas levels of growth hormone reduced significantly only at 12 h and 36 h of treatment (p<0.01). TSH, T(4) and PRL rebound was observed from the first day onwards after stopping dopamine. Dobutamine administration did not alter the profile of any of the hormones and no rebound was observed after stopping treatment. CONCLUSION: Dopamine and dobutamine both increase the systemic blood pressure, though dopamine is more effective. Dopamine reduces serum levels of TSH, T(4) and PRL in VLBW infants but such suppression is quickly reversed after treatment is stopped. Further research is required to assess if short-term iatrogenic pituitary suppression has longer-term consequences.     

Thyrotropin, prolactin and growth hormone response to synthetic thyrotropin-releasing hormone in newborn infants.

The effects of 50 microgram synthetic thyrotropin-releasing hormone (TRH) intravenously on thyrotropin (TSH), prolactin (PRL) and growth hormone (GH) levels were studied in 8 normal male newborns during the first hours of life. Mean plasma GH concentrations were similar to baseline values during the period of study; on the contrary, plasma PRL and TSH values increased in all infants after TRH administration. These data demonstrate a normal pituitary reserve of PRL and TSH in the early period of human life.     

Thyroid function in healthy and sick very-low-birth-weight infants--thyrotropin and free thyroxine levels until the sixth week of age

Hypothyroxinemia in preterm infants without congenital hypothyroidism is associated with developmental delay. Longitudinal information on thyroid function in very-low-birth-weight (VLBW, <1,500 g birth weight) infants is limited: we present data on thyroid function in sick and healthy VLBW infants until 6 weeks of age. Free T(4) and TSH levels routinely obtained on days 14-21 and days 35-49 in 92 consecutive VLBW infants were correlated retrospectively with neonatal morbidity. Free T(4) levels were positively correlated with gestational age; an independent effect of neonatal disease on thyroid function was not detectable.     

急性白血病化疗对垂体、性腺、甲状腺激素的影响

目的评价儿童急性白血病(AL)及联合化疗对其垂体、性腺、甲状腺激素的影响。方法测定37例(男23例,女14例)AL患儿化疗前后和20例对照组血清促卵泡激素(FSH)、黄体生成素(LH)、睾酮(T)、雌二醇(E2)、催乳素(PRL)、生长激素(GH)、促甲状腺激素(TSH)、游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)水平。结果AL患儿FSH、LH、T、E2、GH、FT4、TSH水平化疗前后及对照组各组差异无显著意义(P>0.05),PRL水平治疗前高于对照组(P<0.01),男童PRL水平治疗前后比较差异有显著意义(P<0.01)。FT3治疗前低于对照组(P<0.001),治疗后趋于正常(P>0.05)。结论AL本身及联合化疗对患儿垂体-性腺轴功能及GH水平无明显影响。AL本身可使PRL水平升高,而化疗药物可抑制男童PRL的分泌。联合化疗对甲状腺功能无影响,FT3水平对判断AL患儿病情变化、疗效及预后有一定参考意义。     

Transthyretin levels are not related to Apgar score in low birth weight and very low birth weight infants

BACKGROUND: Previous studies have reported an increased incidence of thyroid dysfunction in premature/low birth weight infants. The cord blood concentrations of transthyretin (TTR), a thyroid hormone binding protein, have also been found to be decreased in preterm infants. While thyroid hormone concentrations are decreased in sick infants, it is not known if physical condition influences TTR levels. Serial concentrations of TTR following birth have not previously been reported. AIMS: To measure serial serum concentrations of TTR in premature infants following birth, and determine whether TTR levels are related to physical condition. METHODS: A cohort of 65 premature very low birth weight (VLBW) and LBW infants were studied. Serum samples were obtained on the day of birth, and for 8 weeks following birth. Apgar scores at birth as well as the incidence of respiratory distress syndrome (RDS) were noted. RESULTS: Baseline serum T4 concentrations and Apgar scores were significantly lower in VLBW infants, while the severity of RDS was significantly higher in the VLBW group. Multivariate analyses revealed that T4 levels were negatively associated with RDS, while TSH concentrations were positively related to gestational age. TTR concentrations were not related to gestational age at birth, Apgar score, or RDS, and did not change markedly over 8 weeks. CONCLUSIONS: These findings suggest that serum TTR concentrations are not related to birth weight/gestational age and are not associated with either clinical condition at birth (as assessed by Apgar score) or the occurrence of RDS. Reference values for TTR concentrations in VLBW and LBW infants are provided from birth to 8 weeks of age.     

PITUITARY-ADRENAL AND TESTICULAR FUNCTION IN PRETERM INFANTS AFTER PRENATAL DEXAMETHASONE TREATMENT

ABSTRACT. Pituitary-adrenal and testicular function was monitored by plasma ACTH and testosterone (T) measurements in preterm newborns (gestational age below 36 weeks), exposed in utero to dexamethasone treatment for prevention of respiratory distress syndrome. A group of age-matched premature newborns and full-term infants served as controls. The cord-blood ACTH level was high in each group (logarithmic means 65-75 ng/l), but decreased within the first 2 days of life to mean levels between 20-30 ng/l on days 3 to 10 inclusive. Dexamethasone treatment had no effect on the postnatal ACTH concentrations when compared with preterm or full-term controls. Similarly, no differences in plasma ACTH were found between untreated preterm and full-term infants during the first 10 days of life. T levels in mixed cord blood were on average 2-3 nmol/l in the preterm male infants. An increase to a mean level of 10 nmol/l was seen in 1 h and 1d samples. Thereafter, the concentration of T decreased to 2-3 nmol/l on days 3-10 postnatally. No effect of dexamethasone treatment was seen on the postnatal pattern of plasma T. When preterm male and full-term male infants were compared, no difference was seen in the T peak in the first day of life. However, the 1-3, and 60-90 day concentrations of T were 2-fold ( p <0.01–0.05) higher in the preterm group. It is concluded that prenatal dexamethasone treatment of the mother does not influence the postnatal pituitary-adrenal function as monitored by ACTH measurements. Likewise, no effect of this treatment was observed on the postnatal testicular activity of preterm male infants. The immediate postnatal peak in plasma T levels persisted longer in the preterm than in the full-term male infants.     

A modified vitamin regimen for vitamin B2, A, and E administration in very-low-birth-weight infants

INTRODUCTION: Very-low-birth-weight (VLBW; birth weight, <1,500 g) infants receive preterm infant formulas and parenteral multivitamin preparations that provide more riboflavin (vitamin B2) than does human milk and more than that recommended by the American Society of Clinical Nutrition. VLBW infants who are not breast-fed may have plasma riboflavin concentrations up to 50 times higher than those in cord blood. The authors examined a vitamin regimen designed to reduce daily riboflavin intake, with the hypothesis that this new regimen would result in lower plasma riboflavin concentrations while maintaining lipid-soluble vitamin levels. METHODS: Preterm infants with birth weight < or =1,000 g received either standard preterm infant nutrition providing 0.42 to 0.75 mg riboflavin/kg/day (standard group), or a modified regimen providing 0.19 to 0.35 mg/kg/day (modified group). The modified group parenteral vitamin infusion was premixed in Intralipid. Enteral feedings were selected to meet daily riboflavin administration guidelines. Plasma riboflavin, vitamin A, and vitamin E concentrations were measured weekly by high-performance liquid chromatography. Data were analyzed with the independent t test, chi, and analysis of variance. RESULTS: The 36 infants (17 standard group, 19 modified group) had birth weight and gestational age of 779 +/- 29 g and 25.5 +/- 0.3 weeks (mean +/- SEM) with no differences between groups. Modified group infants received 38% less riboflavin (0.281 +/- 0.009 mg/kg/day), 35% more vitamin A (318.3 +/- 11.4 microg/kg/day), and 14% more vitamin E (3.17 +/- 0.14 mg/kg/day) than standard group infants. Plasma riboflavin rose from baseline in both groups but was 37% lower in the modified group during the first postnatal month (133.3 +/- 9.9 ng/mL). Riboflavin intake and plasma riboflavin concentrations were directly correlated. Plasma vitamin A (0.222 +/- 0.022 microg/mL) and vitamin E (22.26 +/- 1.61 /mL) concentrations were greater in the modified group. CONCLUSIONS: The modified vitamin regimen resulted in reduced riboflavin intake and plasma riboflavin concentration, suggesting plasma riboflavin concentration is partially dose dependent during the first postnatal month in VLBW infants. Modified group plasma vitamin A and vitamin E concentrations were greater during the first month, possibly because the vitamins were premixed with parenteral lipid emulsion. Because of the complexity of this protocol, the authors suggest that a parenteral multivitamin product designed for VLBW infants which uses weight-based dosing should be developed.     

COMBINED TEST OF HYPOTHALAMIC-PITUITARY FUNCTION IN GROWTH-RETARDED CHILDREN TREATED WITH GROWTH HORMONE: II. Secretion of LH, FSH, TSH, Prolactin and ACTH

Abstract. P. C. Eskildsen, B. B. Jacobsen, K. W. Kastrup, S. Krabbe, P. E. Lebech and K. E. Petersen (The Children's Hospital Fuglebakken, Herlev Hospital and Frederiksberg Hospital, Copenhagen, Denmark). Combined test of hypothalamic-pituitary function in growth-retarded children treated with growth hormone. Acta Paediatr Scand, Suppl. 277: 14, 1979.—A total number of 23 patients treated with human growth hormone were retested by use of a combined pituitary stimulation test. Plasma concentrations of GH, FSH, LH, TSH, T₄, T₃, prolactin (PRL), ACTH and cortisol were measured before and after stimulation with hypoglycemia, TRH and LHRH. The test was performed in patients with persistent GH deficiency (group A) and patients with transitory GH deficiency (group B). In group A a normal pubertal development was found in three patients, whereas in prepubertal subjects the FSH/LH responses were smaller than those of prepubertal patients in group B. Also plasma ACTH increase was less pronounced in group A patients than in group B. In contrast, the plasma TSH and PRL responses were more sustained in group A than in group B. The secretory pattern of TSH and PRL was comparable in the two groups of patients. Thus, in patients with persistent GH deficiency additional multiple disturbances of the hypothalamic-pituitary function often appeared whereas in most patients with transitory GH deficiency the combined pituitary test was normal at the reinvestigation.     

Pituitary-adrenal and testicular function in preterm infants after prenatal dexamethasone treatment

Pituitary-adrenal and testicular function was monitored by plasma ACTH and testosterone (T) measurements in preterm newborns (gestational age below 36 weeks), exposed in utero to dexamethasone treatment for prevention of respiratory distress syndrome. A group of age-matched premature newborns and full-term infants served as controls. The cord-blood ACTH level was high in each group (logarithmic means 65-75 ng/l), but decreased within the first 2 days of life to mean levels between 20-30 ng/l on days 3 to 10 inclusive. Dexamethasone treatment had no effect on the postnatal ACTH concentrations when compared with preterm or full-term controls. Similarly, no difference in plasma ACTH were found between untreated preterm and full-term infants during the first 10 days of life. T levels in mixed cord blood were on average 2-3 nmol/l in the preterm male infants. An increase to a mean level of 10 nmol/l was seen in 1 h and 1 d samples. Thereafter, the concentration of T decreased to 2-3 nmol/l on days 3-10 postnatally. No effect of dexamethasone treatment was seen on the postnatal pattern of plasma T. When preterm male and full-term male infants were compared, no difference was seen in the T peak in the first day of life. However, the 1-3, and 60-90 days concentrations of T were 2-fold (p less than 0.01-0.05) higher in the preterm group. It is concluded that prenatal dexamethasone treatment of the mother does not influence the postnatal pituitary-adrenal function as monitored by ACTH measurements. Likewise, no effect of this treatment was observed on the postnatal testicular activity of preterm male infants. The immediate postnatal peak in plasma T levels persisted longer in the preterm than in the full-term male infants.     

Effect of metoclopramide treatment on thyrotropin and prolactin levels in sick neonates

The present study was carried out to define whether dopaminergic mechanisms contribute to the regulation of thyrotropin (TSH) and prolactin PRL release in the immediate neonatal period. 14 full-term neonates with a mean birth weight of 3,240 g and a mean gestational age of 39.1 weeks were administered metoclopramide (MTC), a specific dopamine antagonist, in a dose of 0.1 mg/kg/day to treat delayed gastric emptying, regurgitation and abdominal distension. Prior to and after 3-day MTC administration, blood samples were taken to determine serum TSH and PRL levels using a radioimmunoassay method. It has been demonstrated that in response to MTC administration PRL increased significantly from 4,010 +/- 383 to 5,478 +/- 441 mU/l (p less than 0.01), while TSH showed only a tendency to rise independent of the pretreatment hormone levels (from 2.85 +/- 0.44 to 3.06 +/- 0.38 mU/L. In healthy control infants and in those infants with similar functional gastrointestinal disturbances who were treated without MTC, serum PRL levels fell significantly from days 3-4 to days 6-7, serum TSH, triiodothyronine and free thyroxine, however, remained unaltered. It is concluded that dopaminergic inhibitory mechanism may be involved in the control of pituitary PRL and TSH release already in the neonatal period.     

Thyroid function tests in preterm infants born to preeclamptic mothers with placental insufficiency

OBJECTIVE: Since preeclampsia causes placental insufficiency, it can be hypothesized that it decreases placental passage of thyroxine (T4) from mother to infant and thus may deepen the transient hypothyroxinemia seen in preterm infants after birth. The aim of this study was to compare thyroid function tests of preterm infants born to preeclamptic mothers with placental insufficiency with preterm infants born to mothers without placental insufficiency. METHODS: Thirty-one preterm infants born to preeclamptic mothers with placental insufficiency were included in the study (group I) and 31 preterm infants born to mothers without placental insufficiency were included as the control group (group II). Thyroid hormone levels were assayed from blood samples obtained from the women before birth and thereafter from the infants at delivery (cord) and on the 1st, 3rd, 7th, and 21st days of life. RESULTS: Cord blood triiodothyronine (T3), free T3 (FT3) and free thyroxine (FT4) levels in group I were lower than in group II, whereas thyrotropin (TSH) and thyroxine binding globulin (TBG) levels were higher. No statistical difference in hormone levels studied at postnatal 1st, 3rd, 7th, and 21st day was found between the two groups. CONCLUSION: Low levels of thyroid hormones and high level of TSH in cord blood in premature infants born to preeclamptic mothers with placental insufficiency suggest intrauterine hypothyroidism. Increase in TSH and thyroid hormone concentrations after birth reveal that the hypothalamic-pituitary-thyroid axis is intact.     

Relationship between free T4 levels and postnatal steroid therapy in preterm infants

Background: Transient hypothyroxinemia is the most common thyroid dysfunction in preterm infants. Hypothalamic–pituitary–thyroid immaturity and non‐thyroidal illness contribute to its etiology. The aim of the present study was therefore to determine the relationship between thyroid hormone status and early postnatal steroid therapy in preterm infants. Methods: A prospective study of premature infants born at <28 weeks of gestation between July 2001 and June 2007 was conducted. Selective postnatal steroid (dexamethasone) therapy was used in lung disease treatment if the infants needed high mean airway pressure‐assisted ventilation and supplemental oxygen at 2 weeks of age. Free T4 (FT4) and thyroid‐stimulating hormone (TSH) levels were assessed at 2 weeks after birth. Blood samples in eight infants were available after starting steroid therapy. Infants receiving steroids (steroid (+); n= 8) were compared to those not receiving steroids (steroid (?); n= 73). Results: The demographic data were not significantly different between the two groups. The neonatal illnesses and drug use were also not significantly different between the groups. The steroid (+) group had significantly lower FT4 and TSH levels at 2 weeks after birth than the steroid (?) group. The increase in FT4 levels after steroid withdrawal was greater than that during the same period in the steroid (?) patients. Conclusion: Even if it cannot be excluded that reduced FT4 and TSH concentrations are caused by non‐thyroidal illness, the present study suggests that postnatal steroid treatment reduces the FT4 and TSH levels in premature infants born at <28 weeks of gestation.     

Urinary S-100B concentrations in term and preterm infants at risk for brain damage

BACKGROUND: Elevated serum concentrations of S-100B, a 21-kDa protein expressed in astroglial cells, has been used to assess cerebral damage after head trauma, infection, ischemia, and perinatal asphyxia. OBJECTIVE: As S-100B is eliminated by the kidneys, we investigated the feasibility of measuring S-100B in urine of newborns with severe perinatal asphyxia, and in very low birth weight (VLBW) preterm infants at risk for neurodevelopmental impairment. METHODS: We first analyzed urine samples of 8 term or near-term newborns without major medical problems, followed by urine samples of 2 term newborns with severe birth asphyxia, and finally urine samples of 8 VLBW (gestational age 24-28 weeks) infants collected every 4 h for up to 10 days. RESULTS: Urinary S-100B concentrations in 8 term or near-term newborns without major medical problems were consistently <1 microg/l. In 2 term newborns with severe asphyxia (Apgar 0/0/0 and 0/2/4) who subsequently had widespread cerebral damage on magnetic resonance imaging, peak urinary S-100B concentrations on the first day of life were 28.1 and 28.4 microg/l, respectively. In 5/8 VLBW infants, urinary S-100B was> microg/l in samples obtained on the first day of life (range 1.2-44.9 microg/l, median 6.8 microg/l). Peak S-100B in urine samples collected during the first 12 h of life were negatively related to gestational age (R(s)=-0.882, p=0.009). Three of the 8 preterm infants had peak urinary concentrations>0 microg/l but neither ultrasound signs of brain damage nor neurodevelopmental delay at 1 year corrected age. CONCLUSIONS: The determination of urinary S-100B concentrations might be helpful in term infants with severe asphyxia, while high urinary S-100B concentrations in preterm infants are to be attributed to immaturity.     

Metabolic and endocrine events at the time of the first feed of human milk in preterm and term infants.

The first feed of breast milk given to a group of 12 term infants was previously shown to increase the levels of blood glucose and plasma insulin, growth hormone (GH), gastrin, and enteroglucagon. We have now studied the effects of the first feed of breast milk in two similar groups of preterm infants, to compare the results with those obtained for the term infant. One group of 8 preterm infants received a bolus (2.5 ml/kg) of breast milk via a nasogastric tube; the other group of 5 infants received a continuous intragastric infusion (2.5 ml/kg per hour) of breast milk. No change occurred in the concentrations of blood glucose, lactate, pyruvate, or ketone bodies, or in plasma insulin, GH, pancreatic glucagon, or enteroglucagon in either the ''bolus fed'' or the ''infusion fed'' group of preterm infants. Thus the marked metabolic and endocrine changes in term infants after the first feed do not occur in preterm infants with standard methods of feeding.     

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.     

TSH, FT4 and T3T evaluation in normal and preterm hospitalized newborns]

Thyroid hormones are essential for foetus and newborn development. Preterm newborns present low levels for thyroid hormones. These low levels are related with disorder in psychomotor and neurological development. In the literature, several studies concerning newborns treated with thyroid hormone have been realized in different conditions; however, there is no consensus about preterm newborn supplementation benefit. OBJECTIVE: The aim of the study was to defined hormonal values used for normal and preterm newborns. MATERIAL AND METHODS: We reported TSH, T3T and T4L levels for 195 normal or preterm newborns, eutrophic or small for gestational age (SGA). RESULTS: A positive correlation was found between hormonal level and gestational age. This work allowed us to define a threshold for preterm newborn according to their gestational age. CONCLUSION: Owing to lack of consensus, those values are useful for clinical and biological follow-up of thyroid function for newborns at risk (SGA and preterm before 32 weeks) during the first year of life. Finally, it would be interesting to study systematic supplementation of thyroid hormone for those infants in a prospective study.     

Plasma thyroid hormones and prolactin in premature infants and their mothers after prenatal treatment with thyrotropin-releasing hormone.

We assayed TSH, triiodothyronine, free thyroxine, and prolactin (PRL) in plasma of women and infants participating in a trial of prenatal thyrotropin-releasing hormone (TRH) treatment for prevention of newborn lung disease. Women in labor at 26-34 wk of gestation received 400 micrograms of TRH i.v. every 8 h (one to four doses) plus 12 mg betamethasone (one or two doses); controls received saline plus betamethasone. Mean cord concentrations in control infants were TSH 9.7 mU/L, triiodothyronine 0.6 nmol/L (40.2 ng/dL), free thyroxine 14.4 pmol/L (1.13 ng/dL), and PRL 67.6 micrograms/L. TRH increased maternal plasma TSH by 100% at 2-4 h after treatment and decreased levels by 28-34% at 5-36 h. In cord blood of treated infants delivered at 2-6 h, TSH, triiodothyronine, and PRL were all increased about 2-fold versus control, and free thyroxine was increased 19%; the response was similar after one, two, three, or four doses of TRH. In treated infants delivered at 13-36 h, cord TSH and triiodothyronine levels were decreased 62 and 54%, respectively, and all thyroid hormones were lower after birth at 2 h of age versus control. We conclude that prenatal TRH administration increases thyroid hormones and PRL in preterm fetuses to levels similar to those normally occurring at term. Pituitary-thyroid function is transiently suppressed after treatment to a greater extent in fetus than mother, and infants born during the early phase of suppression do not have the normal postnatal surge in thyroid hormones.     

Catch-up growth of head circumference of very low birth weight,small for gestational age preterm infants and mental development to adulthood

OBJECTIVE: To examine the influence of postnatal energy quotient (EQ, energy intake/kg body weight per day) on head circumference (HC) growth and mental development of very low birth weight (VLBW), small for gestational age (SGA, <10th percentile) preterm infants. STUDY DESIGN: SGA VLBW preterm infants (n = 46) with primarily symmetric intrauterine growth restriction were compared with 62 appropriate for gestational age (AGA) VLBW preterm infants and 73 term infants from the Bonn Longitudinal study. RESULTS: Twenty-seven of 46 (59%) of the SGA preterm infants showed complete HC catch-up growth by the age of 12 months, but mostly before 6 months after term (HC catch-up group). These infants had significantly higher mean EQs from day 2 to 10 than the group of 19 infants without HC catch-up (EQ, 95 vs 78). Mean EQs correlated significantly with developmental and intelligence quotients (DQ/IQ) from 18 months to 6 years. As adults, the HC of the HC catch-up group was not significantly different from that of the AGA preterm infants, the term infants, and their parents. The group without HC catch-up had smaller HC as adults. CONCLUSIONS: Our data suggest that early postnatal high-energy nutrient intake for SGA preterm infants is needed to promote HC catch-up growth and to prevent negative consequences of undernutrition.     

Plasma protein Z levels in healthy and high-risk newborn infants

AIM: To evaluate plasma protein Z (PZ) levels in healthy and high-risk newborn infants. METHODS: A longitudinal observational study was conducted. Inclusion criteria were: healthy term and preterm newborns normal for gestational age and newborns belonging to one of the following groups: newborns small for gestational age (SGA), newborns affected by respiratory distress syndrome (RDS), newborns from mothers with pre-eclampsia. Newborns with sepsis, congenital malformation or haemorrhagic disorders were excluded. Plasma PZ levels, protein C (PC) concentration, PC activity and protein-induced vitamin K absence levels were measured. RESULTS: 53 newborns were enrolled into the study. PZ and PC antigen levels varied significantly among analysed subgroups on day 1 (p < 0.01): lower levels of these inhibitors were found in RDS newborns (group C), newborns from mothers affected by pre-eclampsia (group D) and SGA newborns (group E) than in healthy term and preterm newborns (groups A and B). CONCLUSION: PZ deficiency occurs in newborns affected by severe RDS, in newborns from pre-eclamptic mothers and in SGA newborns, probably owing to activated coagulation in the first two conditions and to reduced PZ synthesis in the last condition.     

Endocrine activity in preterm and full-term lambs. 1. Adrenal response to synacthen. 2. Thyroid response to ovine thyroid-stimulating hormone or thyrotropin-releasing hormone

Neonatal endocrine status was studied in 14 lambs born 7 days before term, after estrogen injection into the ewes, and in 15 full-term animals. Plasma cortisol and triiodothyronine (T3) levels were depressed during the first hours of life in preterm lambs and plasma reverse T3 levels were significantly higher than in controls. The rise in plasma cortisol levels after Synacthen injection was significantly lowered by prematurity, suggesting reduced sensitivity of the adrenal cortex to ACTH. After ovine TSH injection, plasma thyroxine (T4) levels increased during a shorter period of time in preterm lambs, resulting in a lowered T4 rise; the T3 response was not affected by prematurity. After TRH injection, the rises in plasma T3 and T4 levels were significantly higher in preterm than in full-term lambs, suggesting a pituitary hypersensitivity to TRH linked to prematurity. Moreover it appeared that the response of reverse T3 to TSH or TRH was very weak.