Birth weight and early lung compliance as predictors of short-term outcome in premature infants with respiratory distress syndrome

In addition to birth weight (BW), respiratory mechanics during the first week of life have been reported to predict outcome in ventilated newborn infants with respiratory distress syndrome (RDS). Most measuring techniques are invasive, requiring the placement of an oesophageal tube or balloon. In the present study the compliance (Crs) and resistance (Rrs) of the total respiratory system were measured without an oesophageal tube , using a commercially available system (PEDS; MAS Inc., Hatfield, Pa.) . The Crs and Rrs were determined once, within 24 hours of birth, in 28 preterm infants requiring mechanical ventilation for RDS. Variables such as gestational age (GA) and BW were also evaluated for their predictive role in outcome. Poor outcome was defined as death from respiratory failure or the development of bronchopulmonary dysplasia (BPD) at 28 days. All non-survivors died of refractory respiratory failure, at a median of age of 6 days. The median Crs of the 21 survivors was 0.5 ml/cm H2O and of the non-survivors 0.21 ml/cm H2O (P = 0.01). Crs below 0.45 ml/cm H2O predicted 15 of the 16 infants who either developed BPD or died (positive predictive value 100%; negative predictive value 92%; sensitivity 94%; specificity 100%). Nine survivors, who subsequently developed B PD, had a median Crs of 0.38 ml/cm H2O. Their Crs was significantly lowe r than that of the infants without evidence of BPD (Crs = 0.61 ml/cm H2O ) (P = 0.01). All of the 12 babies without BPD who survived had median C rs values above 0.45 ml/cm H2O. The median Rrs of the 9 infants with BPD (96 cm H2O/l/s) was also significantly higher than the Rrs value of the non-BPD group (59 cm H2O/l/s) (P = 0.05). When stepwise multiple logistic regression was applied to predict outcome, the only variable that could be entered at a 0.05 level of significance was BW. Uncorrected compliance entered the second step, but did not reach statistical significance. We conclude that in premature infants with RDS, BW is a strong predictor of outcome. Although determination of the Crs within the first 24 hours after birth did not add significance to this predictive model, it was nevertheless a useful parameter to determine respiratory morbidity and mortality.

The prenatal role of thyroid hormone evidenced by fetomaternal Pit-1 deficiency

The role of thyroid hormone in the human fetus is uncertain; a significant amount of T4 is transferred from the maternal to the fetal circulation. A mother-infant pair was found to be heterozygotic for a point mutation in codon 271 of the gene encoding Pit-1, a pituitary-specific transcription factor regulating somatotrope, lactotrope, and thyrotrope function. At birth, serum T4 was undetectable in mother and infant. The newborn presented with a striking delay of respiratory, cardiovascular, neurological, and bone maturation. Despite replacement therapy since birth, neurological development of the infant is impaired. Fetomaternal Pit-1 deficiency resulted in unmitigated fetal hypothyroidism that unmasked thyroid hormone as a potent endogenous drive of fetal maturation and revealed placental transfer of maternal T4 as a rescue mechanism for infants with congenital hypothyroidism, preventing fetal and neonatal symptoms of thyroid deficiency and safeguarding developmental potential.

Diaphragmatic hernia in Denys-Drash syndrome

We report on a newborn infant with male pseudohermaphroditism and glomerular lesions (Denys-Drash syndrome) but without Wilms tumor. A constitutional heterozygous mutation in the WT1 gene (366Arg to His) was identified. In addition the child had a large diaphragmatic hernia, so far not described in Denys-Drash syndrome. The expression of the WT1 gene in pleural and abdominal mesothelium and the occurrence of diaphragmatic hernia in transgenic mice with a homozygous WT1 deletion strongly suggests that the diaphragmatic hernia in this patient is part of the malformation pattern caused by WT1 mutations.

Dopamine suppresses thyroid-stimulating hormone secretion in neonatal hypothyroidism

The infusion of dopamine, a hypophysiotropic catecholamine, which inhibits release of thyroid stimulating hormone (TSH), is the inotropic therapy of first choice in neonatal intensive care. Newborns with primary hypothyroidism are at increased risk of cardiocirculatory morbidity and are screened by measuring serum TSH concentrations. In an infant with both congenital heart disease and neonatal hypothyroidism, withdrawal of dopamine infusion was documented to evoke a doubling of serum TSH levels within 40 min, a finding suggestive of an inhibitory effect of dopamine administration on neonatal TSH hypersecretion. As a result, dopamine therapy may be a pitfall in TSH screening for neonatal hypothyroidism.

Asplenia syndrome and isolated total anomalous pulmonary venous connection in siblings

We report on a family with asplenia syndrome in one and total anomalous pulmonary venous connection (TAPVC) in the other sib. Both conditions are rare, may have a genetic cause and belong to a spectrum of laterality disorders. This suggests that both asplenia syndrome and TAPVC in this family are the clinical expression of a single genetic disorder.

Flat chest in survivors of bronchopulmonary dysplasia

Pulmonary mechanics as well as chest wall width and depth were measured in 52 1-year-old survivors of newborn lung disease. Of the 52 patients examined, 22 had developed bronchopulmonary dysplasia (BPD). Chest wall depth was significantly less in the patients who survived with development of BPD compared with those who did not develop BPD. Pulmonary resistance and chest wall width-to-depth ratio were significantly increased in the patients with BPD. Because the chest wall of infants is highly compliant, we suggest that the flatter chest in patients with BPD could result from the abnormal pulmonary mechanics.

Properties of thyroid-stimulating hormone and cortisol secretion by the human newborn on the day of birth

Secretory activation of the thyroid and adrenal glands is a hallmark of the neonatal adaptation to extrauterine life. TSH and cortisol play key roles in these axes. The highest serum concentrations of TSH attained over the full span of human life are normally found shortly after birth. Serum cortisol is also known to be elevated in the immediate postnatal period. However, the dynamics of TSH and cortisol secretion have hitherto not been documented on the day of birth. To study the properties of neonatal TSH and cortisol secretion, we obtained arterial blood at regular intervals (every 20 min for 6 h) from nine polycythemic newborns (gestational age, 34-41 weeks) on the first and/or fourth days after birth during a therapeutic, standardized, isovolumetric, partial exchange transfusion. One premature infant had received betamethasone antenatally. The serum TSH level of an infant with congenital hyperthyroidism of transplacental origin was also measured at the postnatal age of 1 h. Deconvolution analysis of the profiles revealed that all infants displayed a combination of basal and pulsatile TSH release. Bursts of TSH secretion occurred at a median interval of 133 min. The median serum TSH half-life was 75 min. On the day of birth, basal TSH secretion and the amplitude of pulsatile TSH secretion were higher than 3 days later. Cortisol was secreted exclusively in a pulsatile fashion. Bursts of cortisol release occurred at a median interval of 69 min. The median serum cortisol half-life was 60 min. Cortisol secretion appeared to shift gradually from a high frequency, low amplitude pattern early on the first day toward a lower frequency, higher amplitude pattern 3 days later. TSH and cortisol secretion were low in the infant who received betamethasone prenatally. Serum TSH was undetectable in the infant with congenital hyperthyroidism. In conclusion, serum TSH concentrations in the human newborn appear to be elevated on the day of birth as a result of amplified basal and pulsatile TSH release, then fall rapidly through a mechanism that decreases the amplitude of TSH secretion and are affected by modulation of the fetal thyroid axis. From the day of birth onward, cortisol was found to be released in an exclusively pulsatile mode, with characteristics that appear to depend on postnatal age and prenatal glucocorticoid exposure.

A new peroxisomal disorder with fetal and neonatal adrenal insufficiency

A boy with a new type of adrenoleukodystrophy is described. This was characterised by fetal and neonatal adrenal insufficiency, a neurological picture as seen in neonatal adrenoleukodystrophy, but with a normal number of peroxisomes in the liver and a peroxisomal dysfunction limited to the very long chain fatty acids and pristanic acid.

Pulmonary mechanics during respiratory distress syndrome in the prediction of outcome and differentiation of mild and severe bronchopulmonary dysplasia

Pulmonary mechanics was prospectively and longitudinally studied in a cohort of 58 infants who suffered from respiratory distress syndrome. The aim was to determine if early compliance and resistance measurements had additional value to simple clinical variables in predicting poor outcome ie nonsurvival or severe bronchopulmonary dysplasia (BPD) at 28 days. Second, we wanted to determine whether and when the recently described type 1 (mild) BPD and type 2 (severe) BPD could be differentiated by means of lung function tests. In a logistic model, neither lung compliance nor pulmonary resistance at days 1 and 4 of life were selected as predictive variables. On the other hand, gestational age and the ventilatory index no. 1 (ventilator frequency x maximal inspiratory pressure) on day 3 were the best early predictors of poor outcome. Type 2 BPD was characterized by a lower lung compliance and a higher pulmonary resistance than type 1 BPD, although the differences were only significant at 28 days. In conclusion, pulmonary function tests were not helpful in the early prediction of poor outcome at 28 days. They might, however, be of value in the follow-up of BPD patients after 28 days.

Intractable asphyxia at birth: analysis of the underlying conditions

A review of clinical and pathological data on 10,000 consecutive deliveries revealed that the incidence of unexpected and intractable asphyxia at birth despite adequate resuscitation was 0.24%. Lung hypoplasia appeared to be the underlying non-viable condition in 22 out of 24 infants. Attention is drawn to congenital neuromuscular disorders which were found to be the cause of lung hypoplasia in at least 4 out of 22 infants. Some helpful hints for diagnosis are given which may contribute to the final decision making.

Child morbidity patterns in two tropical seasons and associated mortality rates

Cross-sectional morbidity recorded during two successive quarterly survey rounds and subsequent 27-months mortality were studied in a random sample of 4238 preschool children in a rural Zairian area. Analysis focuses on morbid patterns, i.e. any combination of the principal signs and symptoms encountered in tropical areas (oedema, marasmus, cough, fever, diarrhoea and tachypnoea). Almost half the children (45-48%) had signs of morbidity, a very high rate. The 3-6 month age group emerged as particularly vulnerable with the highest prevalences of all morbid patterns except for isolated fever. Isolated cough was more prevalent in the dry season probably as an effect of nightly indoor woodburning. All other morbid patterns were significantly more prevalent in the rainy season. Diarrhoea with cough was found to constitute half of all cases of diarrhoea. The results show that with a few simple questions on major symptoms and a brief examination by paramedical health workers, children with an increased risk of death can be identified. The method can be applied at under-5 clinics. Prognosis is particularly bad in severe malnutrition, especially when associated with diarrhoea, in diarrhoea with cough, cough with fever/tachypnoea and for children who are found sick both in the rainy and the subsequent dry season.

Dopamine inhibits growth hormone and prolactin secretion in the human newborn

Dopamine is frequently used in neonatal intensive care for its vasopressor, renal vasodilating, and cardiac inotropic properties. The effect of i.v. dopamine infusion on neonatal pituitary hormone secretion is currently unknown. We observed strikingly low serum concentrations of growth hormone (GH) and prolactin (PRL) during a therapeutic, standardized, isovolumetric, partial exchange transfusion (blood sampling every 20 min for 6 h) in two polycythemic neonates requiring intensive therapy, including continuous dopamine infusion. In addition, the secretion of GH and PRL was studied in three neonates with symptomatic polycythemia (gestational age 34-38 wk; birth weight 2110-2530 g; postnatal age 10-30 h) during a partial exchange transfusion, including an intervening dopamine infusion (8 micrograms/kg/min i.v. for 2 h). The GH and PRL profiles were evaluated by deconvolution analysis. Initially, the three newborns exhibited high-amplitude, pulsatile GH secretion and continuously elevated PRL release. During the dopamine infusion, GH secretion was virtually abolished and PRL release was reduced by at least 50%. Dopamine withdrawal was associated with a rebound release of GH and PRL. Finally, serum GH and PRL concentrations were studied in nine nonpolycythemic newborns (gestational age 31-40 wk; birth weight 1680-4000 g; postnatal age 2-28 d) at the end of a prolonged dopamine infusion (3-5 micrograms/kg/min i.v. for 2-27 d). Within 2 h after dopamine withdrawal, GH and PRL levels increased a median 3-fold and 10-fold respectively. These data concord to indicate that dopamine is a potent inhibitor of GH and PRL secretion in the human newborn.

Congenital pulmonary lymphangiectasis with chylothorax: a heterogeneous lymphatic vessel abnormality

We report on 7 perinatal autopsy cases of primary congenital pulmonary lymphangiectasis (CPL) with bilateral chylothorax. This study demonstrates that primary CPL is often complicated by chylous pleural effusions with ensuing pulmonary hypoplasia. Conversely, CPL appears to be a constant pathological finding in spontaneous congenital chylothorax. These observations indicate a common pathogenesis for both disorders. The basic defect is not an intrinsic lung abnormality, but a developmental error of the lymphatic system resulting in a pulmonary lymphatic obstruction sequence. The cause of CPL is heterogeneous. Apparently, most cases are sporadic occurrences. We report the second instance of CPL in sibs. This indicates that some cases are genetically determined with autosomal recessive inheritance. CPL may also be part of a multiple congenital anomalies (MCA) syndrome such as Noonan, Ullrich-Turner, and Down syndrome.

[Familial occurrence of esophageal atresia]

Two siblings with esophageal atresia are reported, and literature data as to familial occurrence and heredity have been reviewed. Until now, only statistical data can be given: the recurrence risk for sibs after one affected child is around 0.5-2% and after two affected children around 20%. The risk for the children of a parent affected by congenital esophageal atresia is estimated at around 3-4%. This is compatible with the recurrence risk of a multifactorial condition in first degree relatives. However, two patients have been described in which the possibility of autosomal dominant transmission has been raised.

Properties of growth hormone and prolactin hypersecretion by the human infant on the day of birth

The neonatal period is the only interval in postnatal life characterized by physiologically elevated plasma concentrations of GH and PRL, two hormones of common origin. To study the secretion of GH and PRL on the day of birth, we obtained at regular intervals (every 20 min for 6 h) blood from seven polycythemic newborns (gestational age 34-41 weeks; birthweight 1600-3960 g; postnatal age 6-23 h) during a therapeutic, standardized, isovolumetric, partial exchange transfusion. Serum GH concentrations were measured by RIA and PRL levels by immunoradiometric assay. Deconvolution analysis of the profiles revealed that all infants displayed a pulsatile pattern of amplified GH release (range 9-191 micrograms/L). Bursts of GH secretion occurred at a median interval of 73 min. The median serum GH half-life was 18 min. All infants had continuously elevated serum PRL concentrations (range 86-191 micrograms/L) and none appeared to release PRL episodically. There was no significant cross-correlation between the secretion of GH and PRL. Mean serum GH concentrations during the 6-h study were higher than in cord serum at birth, whereas PRL and insulin-like growth factor-1 levels were lower than at birth. In conclusion, the neonatal hypersomatotropism appears to be characterized by high-amplitude, high-frequency, pulsatile secretion of GH without a prolonged GH half-life, whereas hyperprolactinemia seems to result from GH-independent, continuous PRL release. The immediate postnatal rise of GH secretion in the human newborn may be related to decreased inhibition by circulating insulin-like growth factor-1.

Pulsatile and sexually dimorphic secretion of luteinizing hormone in the human infant on the day of birth

Experimental evidence indicates that the hypothalamic-pituitary-gonadal axis is operational and sexually dimorphic in the mammalian fetus and newborn. We examined the dynamics of human luteinizing hormone (LH) secretion in five male and three female infants on the day of birth, after 34-41 wk of gestation. The infants were polycythemic, and blood samples were obtained every 20 min for 160 to 360 min during a therapeutic, standardized, isovolumetric, partial exchange transfusion. Serum LH was measured by an immunoradiometric assay that does not cross-react with human chorionic gonadotropin. The serum profiles of LH presented a striking sex dimorphism with elevated LH levels in male compared with female newborns. Deconvolution analysis of all male LH profiles was consistent with a high-frequency, pulsatile secretory pattern. Testosterone, measured in a pooled serum sample of each infant, was 10-fold higher in male than in female newborns. These results document pulsatile and sexually dimorphic secretion of LH in the human infant as early as the first day of postnatal life. It is possible that the augmented LH secretion in the male newborn participates in the neonatal rise of the serum testosterone concentration.

Outcome of respiratory distress syndrome at 28 days: a prospective longitudinal study

Fifty eight newborn infants with respiratory distress syndrome (RDS) were prospectively studied, in order to determine clinical variables prognostic of poor outcome at 28 days. Twenty six infants survived without bronchopulmonary dysplasia (BPD), 13 had Type 1 BPD, 4 had Type 2 BPD and 15 infants died before 28 days. Survivors without BPD had higher birthweights and gestational ages. Among the other infants, severity of initial lung disease was the best discriminator between outcome groups: Type 1 BPD infants had the best lungs at onset, and the nonsurvivors had the worst lungs. Stepwise multiple logistic regression identified gestational age and the ventilatory index number 1 (VI1) (= respirator frequency x maximal inspiratory pressure) at day 3 as the most useful variables to predict "poor outcome" (nonsurvival or Type 2 BPD). Ninety five percent of the infants were correctly classified using a cut-off probability of 0.5. We conclude that RDS outcome at 28 days is determined at a very early stage and that poor outcome can be predicted with reasonable accuracy at three days of age.

Outcome of respiratory distress syndrome at 28 days: a prospective longitudinal study

Fifty eight newborn infants with respiratory distress syndrome (RDS) were prospectively studied, in order to determine clinical variables prognostic of poor outcome at 28 days. Twenty six infants survived without bronchopulmonary dysplasia (BPD), 13 had Type 1 BPD, 4 had Type 2 BPD and 15 infants died before 28 days. Survivors without BPD had higher birthweights and gestational ages. Among the other infants, severity of initial lung disease was the best discriminator between outcome groups: Type 1 BPD infants had the best lungs at onset, and the nonsurvivors had the worst lungs. Stepwise multiple logistic regression identified gestational age and the ventilatory index number 1 (VI1) (= respirator frequency x maximal inspiratory pressure) at day 3 as the most useful variables to predict "poor outcome" (nonsurvival or Type 2 BPD). Ninety five percent of the infants were correctly classified using a cut-off probability of 0.5. We conclude that RDS outcome at 28 days is determined at a very early stage and that poor outcome can be predicted with reasonable accuracy at three days of age.

Pathogenesis of congenital cystic adenomatoid malformation of the lung

Congenital cystic adenomatoid malformation is a rare developmental abnormality of the lung. In most earlier reported cases, the anatomy of the bronchial tree was poorly documented. We describe four cases studied following autopsy. Post-mortem bronchography or serial microscopical examination showed segmental bronchial absence or atresia in each of them. Our observations provide further evidence pointing to bronchial atresia as being the primary defect leading to the development of congenital cystic adenomatoid malformation. The morphology of the lesion, i.e. the type of malformation, is determined by the extent of dysplastic lung growth beyond the atretic segment. The aetiology of the bronchial atresia is probably heterogeneous and may either represent a primary malformation, or be the result of vascular disruption.

Effect of prenatal betamethasone/thyrotropin releasing hormone treatment on somatosensory evoked potentials in preterm newborns

The maternal administration of betamethasone and thyrotropin releasing hormone (TRH) to accelerate the maturation of the fetus is an increasingly adopted strategy to prevent neonatal morbidity in preterm infants. The effect of this prenatal treatment on the neural maturation of the infant was assessed by measuring somatosensory evoked potentials (SEP) in preterm infants (gestational age 29-36 wk) on the 1st postnatal day, at the age of 1 wk, and before discharge. The N1 latency values of the SEP obtained in 14 infants who were exposed prenatally to betamethasone/TRH were compared with the N1 latencies measured in 12 control infants. On the 1st postnatal day, the N1 latencies in the betamethasone/TRH-treated infants were strikingly shorter (p less than 0.01) than in the controls. However, at the age of 1 wk and at discharge, the N1 latency values of both groups were similar. In conclusion, the present study provides the first solid evidence for the concept that the prenatal exposure to betamethasone/TRH accelerates the SEP-assessed neural maturation of the human fetus, that this prenatal acceleration is followed by a compensatory relative deceleration during the early neonatal period, and that the subsequent SEP-assessed neural maturation proceeds at a normal velocity.

[Stridor in infants: sometimes not so innocent]

Stridor is a frequent symptom in the neonate. Often it consists of a discrete inspiratory stridor in an alert child or of a transient symptom of a viral respiratory infection. In both cases no specific therapy is required. Whenever stridor occurs in the first months of life, or when it is severe or chronic, or when stridor also persists throughout expiration, an underlying anatomic anomaly frequently exists. The following steps are important to the diagnostic management: besides a detailed and complete history and physical examination, an X-ray of the airways and, if necessary, laryngo/bronchoscopy, angio(cardio)graphy or computerized tomography of the chest and the cervical region. Subsequently, appropriate therapeutic management can be initiated by proficient and accomplished physicians.

Unilateral thalamic haemorrhage in the pre-term and full-term newborn

One full-term and three premature newborns with a unilateral thalamic haemorrhage are reported. The lesion was diagnosed using cranial ultrasonography and confirmed in three using magnetic resonance imaging. Severe perinatal asphyxia occurred in all infants. The neonatal clinical history, subsequent neuro-developmental outcome and neuroimaging findings are discussed. As the prognosis appears to be much better than for infants with bilateral thalamic densities, it is important that this type of lesion is recognised as a separate entity.

Subcapsular hemorrhage of the liver and hemoperitoneum in premature infants: report of 4 cases

The occurrence of a subcapsular hemorrhage of the liver (SHL) with associated hemoperitoneum in four very low birth weight infants (VLBW) is described. We conclude from the analysis of these four cases and a review of the literature, that the pathogenesis of SHL is multifactorial, which emphasizes the extreme vulnerability of these infants.