A. Mautone

Rapid detection of neonatal sepsis using polymerase chain reaction

Clinical diagnosis of sepsis in newborn infants is not easy and there is no laboratory test with 100% specificity and sensitivity, with the exception of blood culture, the results of which are not available for at least 48–72 h. Polymerase chain reaction methodology has been used to diagnose different bacterial, viral and protozoal infections, and the possibility of amplifying the DNA region common to all bacteria could represent an optimal method for the diagnosis of sepsis. The authors have performed PCR in a group of 33 neonates at risk for early‐onset sepsis, correlating molecular data with blood culture results. The presence of bacterial DNA in blood samples was evaluated, amplifying the DNA region encoding the 16S rRNA. There were no false negative results (four positive blood cultures and four positive PCR), with competitive costs and time. This method also allows the diagnosis of sepsis due to uncommon species and also, using a second PCR with specific primers, an aetiological diagnosis.

Early Low-Dose Hydrocortisone in Very Preterm Infants: A Randomized, Placebo-Controlled Trial

Background: Several reports indicate a decreased cortisol response to adrenocorticotropic hormone in preterm infants developing chronic lung disease and in preterm infants with refractory hypotension. Low-dose hydrocortisone (HC) may allow for beneficial effects. Objective: Our aim was to assess whether HC is able to increase survival without chronic lung disease. Methods: We performed a double-blind, randomized, placebo-controlled trial. Fifty mechanically ventilated infants (birth weight: 500–1,249 g) were randomized to receive treatment (HC 0.5 mg/kg/12 h for 9 days, then HC 0.5 mg/kg/24 h for 3 days) or placebo. Major outcome was survival without oxygen dependence at 36 weeks of postconceptional age (O2-free survival). Results: The basic characteristics were similar between the two groups. O2-free survival was higher in the HC group (64 vs. 32%). The advantage was particularly evident among infants without antenatal steroids. The mortality rate was 16% in the HC group versus 40% in the control group (difference not significant). Hypotension after recruitment was reduced by HC (0 vs. 30%). The incidence of gastrointestinal perforation and other adverse effects was similar between the two groups. Conclusions: HC prophylaxis improved O2-free survival and early cardiocirculatory function in our population, without important short-term effects. The neurodevelopmental outcome will be assessed at 2 years.

Gastric electrical activity and gastric emptying in term and preterm newborns.

The aims of this study were to evaluate the gastric electrical activity and gastric emptying in preterm and term newborns and to assess the development of gastric motility by comparing newborns of different gestational ages. The cutaneous electrogastrography and the ultrasonographic study of the gastric emptying were performed before and after milk formula in three groups of infants: 12 preterm newborns with a gestational age of 28–32 weeks, 11 preterm newborns with a gestational age of 32–36 weeks, and 10 full‐term newborns with a gestational age of 36–40 weeks. All recording sessions were performed 1 week after infants had reached full enteral feeding. The percentage of normal slow waves was similar in the three groups but it was not predominant compared to tachygastria in the earliest premature infants (59.3% (12.7–92.3) vs. 29.6% (3.7–78.8); P < 0.05). In addition, a progressive increase in the normal slow wave percentage (59.3% (17.4–87.4), 60.9% (38.1–89.7), 77.8% (66.4–84.8); P < 0.05) was observed as gestation advanced. As regards gastric emptying parameters, the antral area was greater and T½ was longer in the preterm newborns of 28–32 weeks than preterm newborns of 32–36 weeks and full‐term newborns (fasting antral area: 0.96 cm2 (0.6–1.5), 0.63 cm2 (0.4–1.2), 0.55 cm2 (0.1–0.9) respectively, P < 0.05; T½: 83.4 min (76.0–108.5), 70 min (57.5–89.5) and 71.8 min (54.9–81.2), respectively P < 0.05). The comparisons of gastric emptying curves made among the three groups showed a reduced antral dilatation in preterm newborns of 28–32 weeks compared to full‐term newborns at 30 and 60 min after a meal. In conclusion, although enteral feeding is important for the development process of gastrointestinal motility, gastric electrical activity and gastric emptying show an intrinsic maturation depending on the gestational age.

Calprotectin levels in meconium.

Aim: To evaluate the effect of gender, gestational age, birthweight, mode of delivery, 5′‐Apgar score and maternal conditions on calprotectin concentrations in meconium. Methods: Calprotectin was measured in 131 neonates, in the first passed meconium. Results: Calprotectin levels (mean ± SD) resulted in 145.2 ± 78.5 mg kg−1 meconium, significantly correlated with birthweight (r=–0.333; p < 0.001), gestational age (r =–0.206; p = 0.018) and 5′‐Apgar score (r= ‐0.243, p= 0.035). The estimated regression model was: calprotectin levels (mg kg−1) = 269.58–41.54 weight (kg); r = 0.383, p < 0.001. No differences were found in relation to gender, mode of delivery and maternal conditions.

Gastric electrical activity and gastric emptying in preterm newborns fed standard and hydrolysate formulas.

Background Because infant formulas containing hydrolyzed cow milk protein are used to reduce feeding intolerance and to improve gastric emptying, the effect on gastrointestinal motility of a hydrolysate formula was compared with that of a standard preterm formula. Methods Thirty-six preterm newborns with a gestational age of 32.2 ± 2.3 weeks were assigned randomly to standard formula or hydrolyzed formula. Cutaneous electrogastrography and ultrasound examination of gastric emptying were performed simultaneously to evaluate gastrointestinal motility before and after the test meal. All recording sessions were performed 1 week after infants had reached full enteral feeding. Results No significant difference in gastrointestinal symptoms was noted in the newborns fed the different formulas. In particular, regurgitation and vomiting were observed in 78% versus 64% of preterm newborns after standard and hydrolyzed formula, respectively (Fisher exact test, not significant). No differences were found in terms of gastric electrical activity and gastric emptying time between the two groups. Conclusions It seems unnecessary to use hydrolysate formulas to improve motility in preterm infants.

Mild ventriculomegaly as a counselling challenge.

Objective: Our purpose was to evaluate the outcome of a group of fetuses with mild ventriculomegaly. Methods: We retrospectively collected all cases of antenatally diagnosed mild enlargement of the lateral cerebral ventricles (tranverse diameter of the atrium between 10 and 15 mm) between 1992 and 1997. Cases were included in the study if no other ultrasonic anomalies (including soft markers) were found. TORCH screening, karyotyping, search for associated anomalies and neurological examination (including imaging) were performed. Outcome information was available for all cases up to 30 months. Results: Fourteen cases were examined. TORCH was always negative, 1 case with a microdeletion of chromosome 1 was identified. During the course of pregnancy, 2 fetuses showed progression to frank hydrocephalus. Five cases of agenesis of the corpus callosum, 1 of lissencephaly and 1 of heterotopia were eventually diagnosed. After birth 2 syndromes were identified. Three babies died during the follow-up period, among the survivors 4 had severe neurological damage, 2 of them had no associated dysmorphic findings. Discussion: A heterogeneous group of central nervous system disorders may manifest antenatally as mild ventriculomegaly. The current management may not be able to identify dangerous conditions that present subtle dysmorphic features, or be able to predict abnormal outcome in most of the cases.

Does Calprotectin Represent a Regulatory Factor in Host Defense or a Drug Target in Inflammatory Disease

Calprotectin, a protein composed by two subunits of 8 and 14 kD respectively, is released by neutrophils in the biological fluids under inflammatory states. For instance, detection of calprotectin in faeces represents a diagnostic tool in the case of inflammatory bowel disease. Quite interestingly, calprotectin is increased in the stool of healthy newborns from day three up to day thirty and, physiologically, this increase may be interpreted as a defense mechanism against yeast and fungi. Therapeutic attempts at inhibiting the deleterious effect of calprotectin have been experimentally made by using lycoricinidol. This natural compound is able to hamper the calprotectin-induced apoptosis on the one hand. On the other hand, the same compound plays a prophylactic role in the course of experimental arthritis in rats.

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 pre‐term 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).

ACID LYSIS OF RED BLOOD CELLS IN NORMAL CHILDREN

Acid lysis of foetal red cells has been investigated by means of an automated procedure with the Fragiligraph.

Lysis of Neonatal Human Erythrocytes in Hypotonic Solutions of Glucose

The rate of lysis of neonatal and adult human red cells in hypotonic solutions of glucose 0.116 and 0.118 m is examined, using an automatic procedure (Fragiligraph). The lysis of neonatal red cells is similar to the lysis of adult red cells. The decrease in osmotic concentration of D-glucose solution induces an increase in the rate of lysis more significantly in neonatal red cells. High density old red cells are the first to lyse in hypotonic solutions of glucose.