Pédiatrie. 1. Comment favoriser le développement de l'oralité en néonatologie [Pediatrics. How can we improve oral feeding in the neonatal intensive care unit?].

Preterm or sick neonates are frequently hampered in establishing a safe and efficient oral feeding. This can delay hospital discharge and impact on parent-child bonding, growth or neurodevelopment. Recent researches identified a pattern of interventions that could allow to reduce these troubles and to shorten hospital stays.

An effector-reduced anti-β-amyloid (Aβ) antibody with unique aβ binding properties promotes neuroprotection and glial engulfment of Aβ.

Passive immunization against β-amyloid (Aβ) has become an increasingly desirable strategy as a therapeutic treatment for Alzheimer's disease (AD). However, traditional passive immunization approaches carry the risk of Fcγ receptor-mediated overactivation of microglial cells, which may contribute to an inappropriate proinflammatory response leading to vasogenic edema and cerebral microhemorrhage. Here, we describe the generation of a humanized anti-Aβ monoclonal antibody of an IgG4 isotype, known as MABT5102A (MABT). An IgG4 subclass was selected to reduce the risk of Fcγ receptor-mediated overactivation of microglia. MABT bound with high affinity to multiple forms of Aβ, protected against Aβ1-42 oligomer-induced cytotoxicity, and increased uptake of neurotoxic Aβ oligomers by microglia. Furthermore, MABT-mediated amyloid plaque removal was demonstrated using in vivo live imaging in hAPP((V717I))/PS1 transgenic mice. When compared with a human IgG1 wild-type subclass, containing the same antigen-binding variable domains and with equal binding to Aβ, MABT showed reduced activation of stress-activated p38MAPK (p38 mitogen-activated protein kinase) in microglia and induced less release of the proinflammatory cytokine TNFα. We propose that a humanized IgG4 anti-Aβ antibody that takes advantage of a unique Aβ binding profile, while also possessing reduced effector function, may provide a safer therapeutic alternative for passive immunotherapy for AD. Data from a phase I clinical trial testing MABT is consistent with this hypothesis, showing no signs of vasogenic edema, even in ApoE4 carriers.

Placental immaturity, endocardial fibroelastosis and fetal hypoxia.

We describe a term newborn who, after a normal gestational course, presented at birth with absent cardiac activity and no spontaneous breathing. Death occurred within 30 h. Autopsy revealed placental villous immaturity, multiple acute hypoxic lesions, but also chronic hypoxic lesions like endocardial fibroelastosis. This striking association of endocardial fibroelastosis and placental villous immaturity is reviewed and correlated with 2 other cases of placental villous immaturity that led to in utero death at 39 and 41 weeks of gestation. Placental villous immaturity must be suspected and looked for by both pediatricians and obstetricians in every case of stillbirth or perinatal asphyxia of unclear origin. In order to minimize the risk of recurrence in further pregnancies, elective cesarean section may be considered.

Neurons in the corpus callosum of the cat during postnatal development.

The corpus callosum (CC) is a major telencephalic commissure containing mainly cortico-cortical axons and glial cells. We have identified neurons in the CC of the cat and quantified their number at different postnatal ages. An antibody against microtubule-associated protein 2 was used as a marker of neurons. Immunocytochemical double-labelling with neuron-specific enolase or gamma-aminobutyric acid antibodies in the absence of glial fibrillary acidic protein positivity confirmed the neuronal phenotype of these cells. CC neurons were also stained with anti-calbindin and anti-calretinin antibodies, typical for interneurons, and with an anti-neurofilament antibody, which in neocortex detects pyramidal neurons. Together, these findings suggest that the CC contains a mixed population of neuronal types. The quantification was corrected for double counting of adjacent sections and volume changes during CC development. Our data show that CC neurons are numerous early postnatally, and their number decreases with age. At birth, about 570 neurons are found within the CC boundaries and their number drops to about 200 in the adult. The distribution of the neurons within the CC also changes in development. Initially, many neurons are found throughout the CC, while at later ages they become restricted to the boundaries of the CC, and in the adult to the rostrum of the CC close to the septum pellucidum or to the indusium griseum. Although origin and function of transient CC neurons in development and in adulthood remain unknown, they are likely to be interstitial neurons. Some of them have well-developed and differentiated processes and resemble pyramidal cells or interneurons. An axon-guiding function during the early postnatal period can not be excluded.

Validation of two echocardiographic indexes to improve the diagnosis of complex coarctations.

OBJECTIVES: Coarctation of the aorta is one of the most common congenital heart defects. Its diagnosis may be difficult in the presence of a patent ductus arteriosus, of other complex defects or of a poor echocardiographic window. We sought to demonstrate that the carotid-subclavian artery index (CSA index) and the isthmus-descending aorta ratio (I/D ratio), two recently described echocardiographic indexes, are effective in detection of isolated and complex aortic coarctations in children younger and older than 3 months of age. The CSA index is the ratio of the distal aortic arch diameter to the distance between the left carotid artery and the left subclavian artery. It is highly suggestive of a coarctation when it is <1.5. The I/D ratio defined as the diameter of the isthmus to the diameter of the descending aorta, suggests an aortic coarctation when it is less than 0.64. METHODS: This is a retrospective cohort study in a tertiary care children's hospital. Review of all echocardiograms in children aged 0-18 years with a diagnosis of coarctation seen at the author's institution between 1996 and 2006. An age- and sex-matched control group without coarctation was constituted. Offline echocardiographic measurements of the aortic arch were performed in order to calculate the CSA index and I/D ratio. RESULTS: Sixty-eight patients were included in the coarctation group, 24 in the control group. Patients with coarctation had a significantly lower CSA index (0.84+/-0.39 vs 2.65+/-0.82, p<0.0001) and I/D ratio (0.58+/-0.18 vs 0.98+/-0.19, p<0.0001) than patients in the control group. Associated cardiac defects and age of the child did not significantly alter the CSA index or the I/D ratio. CONCLUSIONS: A CSA index less than 1.5 is highly suggestive of coarctation independent of age and of the presence of other cardiac defects. I/D ratio alone is less specific than CSA alone at any age and for any associated cardiac lesion. The association of both indexes improves sensitivity and permits diagnosis of coarctation in all patients based solely on a bedside echocardiographic measurement.

Development of a real-time PCR for the specific detection of Waddlia chondrophila in clinical samples.

Waddlia chondrophila is considered as an emerging human pathogen likely involved in miscarriage and lower respiratory tract infections. Given the low sensitivity of cell culture to recover such an obligate intracellular bacteria, molecular-based diagnostic approaches are warranted. We thus developed a real-time PCR that amplifies Waddlia chondrophila DNA. Specific primers and probe were selected to target the 16S rRNA gene. The PCR specifically amplified W. chondrophila but did not amplify other related-bacteria such as Parachlamydia acanthamoebae, Simkania negevensis and Chlamydia pneumoniae. The PCR exhibited a good intra-run and inter-run reproducibility and a sensitivity of less than ten copies of the positive control. This real-time PCR was then applied to 32 nasopharyngeal aspirates taken from children with bronchiolitis not due to respiratory syncytial virus (RSV). Three samples revealed to be Waddlia positive, suggesting a possible role of this Chlamydia-related bacteria in this setting.

Health-related quality of life in long-term survivors of relapsed childhood acute lymphoblastic leukemia.

BACKGROUND: Relapses occur in about 20% of children with acute lymphoblastic leukemia (ALL). Approximately one-third of these children can be cured. Their risk for late effects is high because of intensified treatment, but their health-related quality of life (HRQOL) was largely unmeasured. Our aim was to compare HRQOL of ALL survivors with the general population, and of relapsed with non-relapsed ALL survivors. METHODOLOGY/PRINCIPAL FINDINGS: As part of the Swiss Childhood Cancer Survivor Study (SCCSS) we sent a questionnaire to all ALL survivors in Switzerland who had been diagnosed between 1976-2003 at age <16 years, survived ≥5 years, and were currently aged ≥16 years. HRQOL was assessed with the Short Form-36 (SF-36), which measures four aspects of physical health and four aspects of mental health. A score of 50 corresponded to the mean of a healthy reference population. We analyzed data from 457 ALL survivors (response: 79%). Sixty-one survivors had suffered a relapse. Compared to the general population, ALL survivors reported similar or higher HRQOL scores on all scales. Survivors with a relapse scored lower in general health perceptions (51.6) compared to those without (55.8;p=0.005), but after adjusting for self-reported late effects, this difference disappeared. CONCLUSION/SIGNIFICANCE: Compared to population norms, ALL survivors reported good HRQOL, even after a relapse. However, relapsed ALL survivors reported poorer general health than non-relapsed. Therefore, we encourage specialists to screen for poor general health in survivors after a relapse and, when appropriate, specifically seek and treat underlying late effects. This will help to improve patients' HRQOL.

Prenatal diagnosis of urinary malformations: results in a series of 93 consecutive cases.

OBJECTIVE: To evaluate the pertinence of prenatal diagnosis in cases of congenital uropathy. STUDY DESIGN: Retrospective evaluation over a period of 6.5 years. METHOD: 93 cases were involved in the comparison of prenatal ultrasonographic diagnosis with neonatal findings, autopsy results, and follow-up data. RESULTS: 33 fetuses had renal parenchymal lesions, 44 had excretory system lesions, and 6 had bladder and/or urethral lesions. Seventy-three pregnancies lead to live births. Eighteen terminations of pregnancy were performed on the parents' request for extremely severe malformations. Two intrauterine deaths were observed, and two infants died in the postnatal period. Prenatal diagnosis was obtained at an average of 27 weeks gestation. Diagnostic concordance was excellent in 82% and partial in 12% of cases with renal parenchymal lesions; the false-positive rate was 6%. For excretory system lesions, concordance was excellent in 87% and partial in 7.4% of cases, with a false-positive rate of 5.6%. Finally, concordance was excellent in 100% of cases of bladder and/or urethral lesions. The overall rate of total concordance was 86%. Partial concordance cases consisted of malformations different from those previously diagnosed, but prenatal diagnosis nevertheless lead to further investigations in the neonatal period and to proper management. The false-positive diagnoses (5.4%) never lead to termination of pregnancy. CONCLUSION: Prenatal diagnosis of congenital uropathy is effective. A third-trimester ultrasonographic examination is necessary to ensure proper neonatal management, considering that the majority of cases are diagnosed at this gestational age.

Dépistage néonatal systématique de la mucoviscidose en Suisse: dès janvier 2011 [Implementation of the neonatal cystic fibrosis screening program in Switzerland: beginning January 2011].

The diagnosis of cystic fibrosis (CF) is often delayed because of the nonspecificity of a wide variety of clinical symptoms at disease onset. Newborn screening for CF has been advocated to reduce delays in diagnosis, facilitating preventive care for early respiratory and nutritional involvement. According to American and European consensus and experience of existing programs, a Swiss Nationwide Cystic Fibrosis Newborn Screening Program started in January 2011. Screening strategy combines two steps: an immunoreactive trypsinogen assay and DNA mutation analysis in dried blood samples at day 4 (Guthrie cards).

Can dopamine prevent the renal side effects of indomethacin? A prospective randomized clinical study.

BACKGROUND: Indomethacin therapy for closure of a patent ductus arteriosus in preterm neonates is responsible for transient renal insufficiency. Dopamine theoretically reduces the renal side effects of indomethacin therapy. PATIENTS: 33 neonates with a mean gestational age of 28.5 weeks who received indomethacin for treatment of a symptomatic PDA were included in a prospective randomized controlled clinical study. METHOD: 15 patients were treated with indomethacin alone (control group), 18 patients with indomethacin and dopamine (study group). Indomethacin was given in a dose of 0.2 mg/kg/dose intravenously, all patients received three doses with intervall of 12 hours. The dose of dopamine was in all patients 4 micrograms/kg per minute commencing 2 hours prior to the first dose of indomethacin and continuing for 12 hours after the third dose. RESULTS: Indomethacin induced a significant increase in serum creatinin (76.3 mumol/l vs 99.7 mumol/l for the control group, and 70.7 mumol/l vs 93.0 mumol/l for the study group), and weight (1259 g vs 1316 g for the control group, and 1187 g vs 1221 g for the study group). The increase systolic blood pressure (61 mmHg vs 65.7 mmHg) in the study group was significant (p < 0.05) but remained unchanged in the control group. The changes between the study group and the control group were not significant either in serum creatinin, fractional excretion of sodium, or weight gain. The failure rate of ductal closure was not different between the two groups. CONCLUSION: The additional use of dopamine does not reduce the renal side effects of indomethacin.

Considerations for prenatal counselling of patients with cardiac rhabdomyomas based on their cardiac and neurologic outcomes.

Cardiac rhabdomyomas are benign cardiac tumours with few cardiac complications, but with a known association to tuberous sclerosis that affects the neurologic outcome of the patients. We have analysed the long-term cardiac and neurological outcomes of patients with cardiac rhabdomyomas in order to allow comprehensive prenatal counselling, basing our findings on the records of all patients seen prenatally and postnatally with an echocardiographic diagnosis of cardiac rhabdomyoma encountered from August, 1982, to September, 2007. We analysed factors such as the number and the location of the tumours to establish their association with a diagnosis of tuberous sclerosis, predicting the cardiac and neurologic outcomes for the patients.Cardiac complications include arrhythmias, obstruction of the ventricular outflow tracts, and secondary cardiogenic shock. Arrhythmias were encountered most often during the neonatal period, with supraventricular tachycardia being the commonest rhythm disturbance identified. No specific dimension or location of the cardiac rhabdomyomas predicted the disturbances of rhythm.The importance of the diagnosis of tuberous sclerosis is exemplified by the neurodevelopmental complications, with four-fifths of the patients showing epilepsy, and two-thirds having delayed development. The presence of multiple cardiac tumours suggested a higher risk of being affected by tuberous sclerosis. The tumours generally regress after birth, and cardiac-related problems are rare after the perinatal period. Tuberous sclerosis and the associated neurodevelopmental complications dominate the clinical picture, and should form an important aspect of the prenatal counselling of parents.

Hemodynamic effects of sodium bicarbonate in critically ill neonates.

OBJECTIVE: To analyze the cardiovascular effects of sodium bicarbonate in neonates with metabolic acidosis. DESIGN: Prospective, open, non-randomized, before-after intervention study with hemodynamic measurements performed before and 1, 5, 10, 20, and 30 min after bicarbonate administration. SETTING: Neonatal intensive care unit, tertiary care center. PATIENTS: Sequential sample of 16 paralysed and mechanically ventilated newborn infants with a metabolic acidosis (pH < 7.25 in premature and < 7.30 in term infants, base deficit > -8). INTERVENTION: An 8.4% sodium bicarbonate solution diluted 1:1 with water (final osmolality of 1000 mOsm/l) was administered in two equal portions at a rate of 0.5 mmol/min. The dose in mmol was calculated using the formula "base deficit x body weight (kg) x 1/3 x 1/2". MEASUREMENTS AND RESULTS: Sodium bicarbonate induced a significant but transient rise in pulsed Doppler cardiac output (CO) (+27.7%), aortic blood flow velocity (+15.3%), systolic blood pressure (BP) (+9.3%), (+14.6%), transcutaneous carbon dioxide pressure (PtcCO2) (+11.8%), and transcutaneous oxygen pressure (PtcO2) (+8%). In spite of the PaCO2 elevation, pH significantly improved (from a mean of 7.24 to 7.30), and the base deficit decreased (-39.3%). Calculated systemic vascular resistance (SVR) (-10.7%) and diastolic BP (-11.7%) decreased significantly, while PaO2 and heart rate (HR) did not change. Central venous pressure (CVP) (+6.5%) increased only slightly. By 30 min after bicarbonate administration all hemodynamic parameters, with the exception of the diastolic BP, had returned to baseline. CONCLUSION: Sodium bicarbonate in neonates with metabolic acidosis induces an increase in contractility and a reduction in afterload.

Neurodevelopmental outcome of neonates treated with nitric oxide for persistent pulmonary hypertension

Persistent pulmonary hypertension of the newborn (PPHN) is a life threatening condition associated with an increased risk of neurodevelopmental impairment. The recommended treatment for this condition is inhaled nitric oxide (iNO) and has been used in our Neonatal Intensive Care Unit since 1998. We prospectively offered neurodevelopmental follow-up to children treated with iNO for PPHN, including extensive neurological evaluation, developmental/cognitive evaluation at 18 months and 3.5-5 years old, and evaluated the rate of severe and moderate handicap and normal neurodevelopmental outcome, compared to a control group and the literature. Population consisted of 29 patients treated only with iNO, born between 01.01.1999 and 31.12.2005 (study group), and 32 healthy term infants born in 1998 in our maternity (control group). During those seven years, 65 infants were admitted in our Unit with PPHN, of whom 40 were treated with iNO alone. 34 children survived (85%) and were offered neurodevelopmental follow-up, 7 children were lost to follow-up due to various reasons. 22 children were examined at the age of 18 months (76%) with a rate of moderate handicap of 22% (2 with expressive language delay, 2 with difficult behavior, and 1 child with moderate hearing loss), and a rate of major handicap of 4.5% (1 child with cerebral palsy due to perinatal stroke, and moderate hearing loss). At preschool age, 17 (50%) were examined, the rate of moderate handicap was 22% (4 borderline intelligence, 1 hearing loss), and the rate of major handicap was 4.5% (one child with cerebral palsy and hearing loss), compared to 26.9% and 0% in the control group. Mean developmental quotient at 18 months was 100.3 ± 8.7 (control group 118.3), and at preschool age mean cognitive indices were within normal limits for the 2 tests performed at 3.5 or 5 years (108 ± 21, 94.4 ± 17). Most of the children with a less favorable neurodevelopmental outcome suffered from birth asphyxia (ruptured uterus, placental abruption, maternal hypotension, diabetic cardiomyopathy), and notably, the 2 children with sensorineural hearing loss both suffered from severe hypoxic-ischemic enkelopathy. Treatment with iNO was not the direct cause of the neurodevelopmental impairments observed in children treated for PPHN.