Carmelo Mamì

Thyroid function in children with cystic fibrosis

Serum concentrations of T4, T3, reverse T3 (rT3), TSH, Thyroxine binding globulin (TBG) and Thyroxine binding prealbumin (TBPA) were measured and a TRH-stimulation test was performed in 10 iodide untreated children affected by cystic fibrosis (CF) and in 84 controls.As compared to the controls, CF patients had lower T4 and rT3, similar T3 and TBG and increased T3:T4 ratios. They also had lower TBPA, but this could not account for the low T4. Finally they had higher basal and TRH-stimulated TSH. Our results indicate subclinical hypothyroidism in CF. The mechanisms responsible for this situation are not elucidated by our data.

Long-term follow up of neonatally diagnosed primary megaureter: rate and predictors of spontaneous resolution

Abstract Objective. Primary megaureter (PM) represents 6–10% of all antenatal displaced urinary malformations. Spontaneous resolution of PM is a well-known event. This long-term follow-up study evaluated the incidence and rate of resolution of PM. Some predictive factors were revised, based on morphological classification and scintigraphic pattern. Material and methods. Sixty neonates with PM were followed. The diagnosis was confirmed by ultrasound examination and 99mTc-DTPA diuretic renal scan. All the observed patients underwent antibiotic prophylaxis. All conservatively treated children were followed from 6 months to 15 years. Follow-up consisted of monthly urine cultures, renal ultrasound and DTPA diuretic renography. Hydroureteronephrosis was considered to have resolved when a retrovesical cross-sectional diameter of ureter less than 6 mm was found. Results. In total, 72 PM were identified in this series. At the end of the follow-up period, 38 PM (52.8%) had resolved, in 18 PM (25%) ureteral dilatation persisted and 16 PM (22.2%) required a surgical procedure. The median age at resolution was significantly affected by presenting hydronephrosis grade and cross-sectional diameter at diagnosis, but not by gender. The 99mTc-DTPA renogram results showed no functional impairment in resolved and persisting cases, even after long-term observation. Conclusions. The data show that 22% of neonatal PM require surgical treatment. Poor drainage on 99mTc-DTPA scan, grade IV–V hydronephrosis and ureteric diameter more than 15.0 mm were statistically significant and independent predictive factors for surgery. The time to spontaneous resolution in neonatally diagnosed PM may exceed 3.6 years, after which recovery is rare.

Incidence of meconium aspiration syndrome in term meconium-stained babies managed at birth with selective tracheal intubation

Abstract The delivery room management of infants born through meconium stained amniotic fluid (MSAF) remains controversial. The aim of this prospective study was to evaluate maternal and neonatal characteristics of MSAF infants and the incidence of meconium aspiration syndrome (MAS) in routine delivery room management which reserved selective intubation for depressed/asphyxiated babies. Between October 1993 and September 1997, a consecutive sample of 3745 full-term infants was analyzed. Of these, 361 were MSAF infants. No significant difference in maternal age, parity, gestational age, sex, low 1 and 5 minute Apgar scores, metabolic acidemia, or need for endotracheal intubation was found between MSAF and non-MSAF infants. Only one of the MSAF infants (0.28%), who needed intubation, developed MAS. Identification of postterm pregnancy and prenatal asphyxia is the best prevention of MAS.

Atrial Natriuretic Peptide and Renin‐Aldosterone Relationship in Healthy Newborn Infants

ABSTRACT. Plasma atrial natriuretic peptide (ANP) and aldosterone concentrations, and plasma renin activity (PRA) were measured by radioimmunoassay concurrently in 20 healthy full term infants, in cord blood, at 24 hours after birth and on the 4th day of life. ANP and aldosterone increased significantly at 24 hours and was persistently elevated on the 4th day of life. PRA remained unchanged during the first four days of life. In cord blood, ANP concentrations were correlated with aldosterone concentrations (r= 0.49, p<0.05) and hematocrit (r= 0.58, p<0.02). At the 24 hours of life, plasma ANP concentrations were correlated with weight loss observed on the 4th day of life (r= ‐0.70, p<0.005), while the percentage changes in plasma aldosterone concentrations were correlated with percentage changes in systolic blood pressure (BP) (r= 0.49, p<0.05). These findings suggest that during the early newborn period ANP and aldosterone act as an integrated system which has a role in regulation blood pressure and intravascular volume homeostasis.

Longitudinal study of blood pressure during the 1st year of life

Systolic and diastolic blood pressure (BP), heart rate and weight were measured in 260 boys and 254 girls, from birth to 12 months of age. Mean±SD values of parameters studied and percentile curves are reported. Systolic and diastolic BP increase significantly during the first 6 months of life and are poorly correlated with weight. In the 1st month of life the diastolic BP values are lower than those reported by others.

Serum levels of resistin and its correlation with adiponectin and insulin in healthy full term neonates

UNLABELLED Resistin and adiponectin are two adipokines involved in the regulation of insulin sensitivity, and have been suggested as mediators of adult metabolic syndrome. AIM The aim of this study was to investigate cord blood levels of resistin, and their postnatal changes in full-term appropriate for gestational age (AGA) neonates. Interrelations between resistin, adiponectin, and insulin, and between resistin and neonatal and maternal anthropometric parameters were also assessed. DESIGN Blood samples were obtained from 30 full term AGA neonates at birth and on the 4th day of life. Anthropometric variables studied included birth weight, length, body mass index (BMI), neonatal weight loss, and mothers BMI. Resistin and adiponectin were determined by ELISA, and insulin by radioimmunoassay method. Data were analyzed using Wilcoxon test and Spearmans correlation coefficient. RESULTS Resistin levels were high at birth and did not change on the 4th day of life. Resistin levels were not correlated to insulin, nor adiponectin levels, nor any anthropometric parameter of neonates or their mothers. Instead, adiponectin levels increased on the 4th day of life, and were correlated to insulin levels. CONCLUSION High levels of resistin in full-term AGA neonates suggest that this hormone may play a role in maintenance of metabolic neonatal homeostasis, but its physiological significance needs further investigation.

The validity of the Apgar scores in the assessment of asphyxia at birth

A prospective study was performed in 613 consecutively live born infants to investigate the validity of 1- and 5-min Apgar scores as an index for asphyxial assessment at birth. The independent and combined relationship between Apgar scores, metabolic acidemia, pulse oximeter (SaPO2) measurements and neonatal outcome were determined. In the term infants 1-min Apgar score was more influenced by the mode of delivery and by gestational age than by asphyxia. Instead, 5-min Apgar score had a high concordance with metabolic acidemia. Infants with low Apgar scores, metabolic acidemia and arterial desaturation have the highest incidence of neonatal intensive care unit admission and poor neonatal outcome. The study suggests that the 5-min Apgar score is useful for immediate clinical assessment and care of the neonate.

Effects of the mode of delivery on ANP and renin-aldosterone system in the fetus and the neonate.

Plasma ANP and aldosterone levels, plasma renin activity (PRA), haematocrit, systolic and diastolic blood pressure (BP), were evaluated in 15 full-term infants delivered by elective Caesarean section (CS group) and in 15 full-term infants delivered vaginally (vaginal group). The mode of delivery did not influence the cord blood levels of ANP and their increase at the 24th hour of life. Instead, PRA was lower and plasma aldosterone levels were higher in the CS group than in the vaginal group. Also haematocrit and BP were influenced by mode of delivery. The haematocrit values were lower in the CS group than in the vaginal group at birth as well at the 24th hour of life. The values of systolic and diastolic BP were the same in both groups, at birth, but at the 24th hour of life increases were observed only in the vaginal group. On the fourth day of life weight loss was the same in both groups. Our findings suggest that the mode of delivery has more influence on neonatal BP adaptation than on neonatal volume homeostasis.

Transient electrocardiographic changes suggesting myocardial ischaemia in newborn infants following tocolysis with beta-sympathomimetics.

Serial electrocardiograms (ECGs) were studied prospectively in 80 apparently healthy newborn infants; 30 infants exposed in utero to prolonged tocolytic therapy (21 to ritodrine and 9 to isoxsuprine) and 50 infants non-exposed in utero to drugs (control group) matched for gestational age, Apgar score, and birth weight. Duration of exposure to tocolysis was at least 30 days (30–180 days) with an oral dosage of 10 mg 3 times daily. ECGs were graded for changes suggestive of ischaemia using the arbitrary grading system described by Jedeikin et al. [12]. In all infants with ECG features of myocardial ischaemia, serum creatine-phosphokinase iso-enzyme (CK-MB) activity was measured. Six out of 21 infants to ritodrine and six out of nine infants exposed to isoxsuprine showed a degree of ECG ischaemia which persisted for several weeks. No control infant presented grade 2 or 3 ECG changes after the 5th day of life. The results of this study seem to show that prolonged tocolytic therapy with β-sympathomimetics has side-effects on the fetal myocardium and suggest that this treatment be reserved only for selective cases and/or for short periods of time.

Visfatin: New marker of oxidative stress in preterm newborns

Background: Oxidative stress is involved in several neonatal conditions characterized by an upregulation in the production of oxidative or nitrative free radicals and a concomitant decrease in the availability of antioxidant species. Oxygen, which is obviously vital to survival, can be highly damaging to neonatal tissue which is known to be poorly equipped to neutralize toxic derivatives. Thus, exposure of the newborn infant to high oxygen concentrations during resuscitation at birth increases oxidative damage. Visfatin is an adipocytokine involved in oxidative stress and an important mediator of inflammation that induces dose-dependent production of both pro-inflammatory and anti-inflammatory cytokines. To our knowledge, the diagnostic value of visfatin as a marker of oxidative stress in preterm newborns has not been investigated. Objective: The aim of this study was to evaluate visfatin levels in preterm neonates resuscitated with different concentrations of oxygen in the delivery room. Patients: Fifty-two preterm newborns with gestational age less than 32 weeks, resuscitated randomly with different oxygen concentrations (40%, 60%, or 100%) were enrolled at the University Hospital of Messina, over a 12-month period to evaluate serum visfatin levels at T0 (within 1 h after birth), T24 h, T72 h, and T168 h of life. Results: At T72 h and T168 h, higher serum visfatin values in the high-oxygen group compared to the low- and mild-oxygen subjects (P = 0.002 and P <0.001, respectively) were noted. Conclusion: The results of this study suggest that visfatin could be a new marker of oxidative stress in preterm newborns.