ACTH and cortisol cord plasma concentrations in preterm and term infants.

OBJECTIVE: To measure the adrenocorticotropic hormone (ACTH) and cortisol (F) cord plasma levels in preterm and term infants in relation to their mode of delivery. STUDY DESIGN: We studied 180 newborns appropriate for gestational age (GA) with birth weights between 365 and 4380 g and GAs between 21 and 41 weeks divided into three groups: born by vaginal delivery (VD), elective cesarean section (ECS) and emergency cesarean section (EMCS). ACTH and F levels were valued with enzyme-linked immunosorbent assay testing. Median concentrations were compared between groups by Student's T-test for independent and paired data. Multiple regression analysis was used to investigate the effect of GA on F and ACTH concentrations. RESULT: A significant positive correlation between GA and plasma concentrations of ACTH (P<0.05) was found in the whole population, but not between GA and F (P=NS). A significant positive correlation was found between GA and plasma concentrations of both ACTH (P=0.01) and F (P=0.03) in VD. In those born by ECS, we demonstrated a positive correlation not only between plasma concentrations of ACTH (P=0.0000) and F (P=0.00002), respectively, with GA, but also a correlation between ACTH and F (P=0.0004). No significant correlations were found in the EMCS group (P=NS). CONCLUSION: Our results suggest simultaneous pituitary-adrenal maturation, which is complete only at term. The responsiveness of preterm babies to different stressful stimulations is similar to the terms' but quantitatively lower, and the secretion of ACTH and F may not suffice in severe pathological circumstances.

[Influence of prolonged treatment with octreotide on GH, IGF I, insulin, ACTH, cortisol, T3, T4 and TSH secretion in a case of congenital chylothorax]. / Influenza del trattamento prolungato con octreotide sulla secrezione di GH, IGFI, insulina, ACTH, cortisolo, T3, T4 e TSH in un caso di chilotorace congenito.

Congenital chylothorax is a rare condition characterized by the accumulation of lymph fluid in the pleural space that causes respiratory and circulatory dysfunctions, immune deficiencies, hypoalbuminemia, electrolyte imbalance and alterations of the coagulation. Mortality rates are elevated and can rise to 50%. Therapy consists in conservative treatment based on thoracic drainage combined with total parenteral nutrition or use of low-fat high-protein diet supplemented with medium chain triglycerides. In case of failure surgical intervention may be considered. During the last years some authors have experienced the use of octreotide with doubtful results. In no case the drug impact on insulin, GH and cortisol secretion in neonatal age has been investigated and only in one case the effect on thyroid hormones has been assessed. We report the case of a 36-week baby with congenital chylothorax treated with octreotide for 42 days. The drug was well tolerated but hormonal level measurements showed a deep depression of insulin secretion unaccompanied by alterations of glucose levels. Levels of GH and TSH showed only a transitory decrease. ACTH and cortisol remained normal. At 5 months, the measurements of hormonal levels did not show significant alterations. It is not possible to determine if such a drug played an essential role in the solution of the pleural effusion, but it is important to emphasize that a prolonged treatment with octreotide has not caused, in our case, persistent hormonal alterations.

[Quantitative ultrasound for the assessment of bone in the preterm infant]. / Utilizzo dell'ultrasonografia quantitativa nella valutazione dello stato minerale osseo del neonato pretermine.

AIM: Preterm infants are at risk of osteopathy of prematurity (OP). The present study aims to assess quantitative ultrasound as a safe and non-invasive method in evaluating bone mineral status in the critically ill preterm infant. METHODS: Sixty preterm infants (27 females) have been evaluated in the Neonatal Intensive Care Unit of the University Hospital of Siena. Gestational age was between 22 and 36 weeks and birth weight ranged between 610 and 3240 g. A single operator did all the measurements on the second metacarpus by the DBM Sonic BP (IGEA). Ultrasound parameters were bone transmission time (BTT, micros) and speed of sound (SOS, m/s). RESULTS: BTT positively increased with birth gestational age (r=0.72, P<0.001, F-Ratio=62.4428), birth weight (r=0.7827, P<0.001, F-Ratio=91.7274) and birth length (r=0.7729, P<0.001, F-Ratio=86.0748). SOS was also related with gestational age (r=0.2937, P<0.023, F-Ratio=5.4768), birth weight (r=0.2634, P<0.042, F-Ratio=4.3250) and birth length (r=0.3252, P<0.011, F-Ratio=6.8596). Small infants for gestational age showed BTT values lower then infants with appropriate size for gestational age (P<0.03). There was no difference between male and female infants. CONCLUSION: Quantitative ultrasound is a non-invasive method, which is easy to perform in a Neonatal Intensive Unit, safe, harmless and gentle. This method detects subtle differences in bone mineral status, according to gestational age, weight and length. Quantitative ultrasound is a useful screening tool for early detection of bone status in newborns and a valid method for the longitudinal assessment of bone in growing children.

[Insulin and glucagon plasma levels in very low birth weight preterm infants of appropriate weight for gestational age]. / Livelli plasmatici di insulina e glucagone in neonati pretermine di peso molto basso appropriato per l'eta gestazionale.

OBJECTIVES: Prematurity is a known risk factor for hypoglycaemia, hyperglycemia, neonatal sepsis and other common neonatal complications, possibly associated with glucoregolatory hormone (insulin and glucagon) alterations. Insulin and glucagon levels change also in relation to gender, mode of delivery and postnatal clinical severity. Because of the lack of reference range in literature, the aim of this study is to assess plasma insulin and glucagon levels in preterm appropriate for gestational age (AGA) infants of birth weight <1500 g (very low birth weight, VLBW) as a function of gestation, birth weight, gender and mode delivery. METHODS: The authors examined 48 preterm AGA infants (mean birth weight 1 163+/-286 g, mean gestational age 28.2+/-2.4 weeks). The infant population was subdivided in relation to gestational age, weight, gender, mode of delivery and assisted ventilation at 5-7(th) days. Plasma glucose, insulin and glucagon levels were assessed in all newborns at birth and at 5-7(th) days of life. Data were analyzed using t-test. RESULTS: A negative correlation between insulin and gestational age was observed (P<0.05). At birth, no significant differences regarding plasma glucose, insulin and glucagon levels were observed as a function of the examined category variables. At the 5-7(th) days of life, insulin levels were significantly higher in newborns with gestational age =or<27 weeks (P<0.02), in the female gender (P<0.02) and in the infants born to emergency Cesarean delivery (P<0.05). CONCLUSIONS: These findings indicate potentially useful reference range values for plasma insulin and glucagon in the VLBW population.