Relationship between placental weight and late-onset circulatory collapse.

BACKGROUND: Late-onset circulatory collapse (LCC) is a serious complication in preterm infants and is increasing in Japan. The underlying pathophysiology is thought to be relative adrenal insufficiency and it is more likely to develop at a young gestational age (GA) and in low birthweight (BW) infants. BW to placental weight ratio (BPR) is an index of pregnancy outcomes and early neonatal morbidity. We aimed to analyze the relationship between LCC and potential predicting factors including BPR. METHODS: This retrospective study included 261 singletons born before 32 weeks of gestation between 2007 and 2017. Perinatal data, including the placental weight and BPR, were collected from medical records and were assessed for their relationship with LCC. Propensity score analysis was performed and matched factors were GA and BW. RESULTS: Sixty-seven infants (25.7%) had LCC (median GA 27.4 weeks). GA and BW differed significantly between the LCC and non-LCC groups (P < 0.001, respectively). The placental weight and BPR of the LCC group were significantly lower than those of the non-LCC group, while Z-score of BPR did not differ significantly between the groups. After propensity score matching, there was a significant difference in the incidence of severe intraventricular hemorrhage (grades III-IV; P = 0.042), but no differences in BPR and Z-score of BPR between the groups. CONCLUSION: In the propensity score analysis matched for GA and BW, there was no significant difference in perinatal factors including BPR between the LCC and non-LCC groups, except for incidence of severe intraventricular hemorrhage.

Exfoliative toxin A staphylococcal scalded skin syndrome in preterm infants.

UNLABELLED: Staphylococcal scalded skin syndrome (SSSS) demonstrates dermal symptoms due to exfoliative toxin (ET) A or ETB produced by Staphylococcus aureus. We examined the association between anti-ETA antibodies and SSSS onset in neonates. Three preterm infants carried an ETA-producing strain of S. aureus, manifesting as either SSSS or bullous impetigo; a full-term infant carrying the same strain was asymptomatic. The infants (n=106) were categorized into three groups according to their gestational age (GA) as follows: <30 weeks, 30-37 weeks, and >37 weeks. The measured levels of anti-ETA antibody in the three infants displaying SSSS were low before the onset of dermal symptoms; only the asymptomatic full-term infant displayed a high antibody level. Anti-ETA antibody levels in the preterm group with a GA of <30 weeks were statistically lower than those in the term infant group; the prevalences of anti-ETA antibodies above a cutoff value in the three groups of neonates were 55 % (18/33) among preterm infants with a GA <30 weeks, 73 % (25/34) among those with a GA of 30-37 weeks, and 90 % (35/39) among infants with a GA >37 weeks. CONCLUSION: The presence of anti-ETA antibodies below a particular cutoff level might be associated with SSSS onset in preterm infants.

Recessive RYR1 mutations in a patient with severe congenital nemaline myopathy with ophthalomoplegia identified through massively parallel sequencing.

Nemaline myopathy (NM) is a group of congenital myopathies, characterized by the presence of distinct rod-like inclusions "nemaline bodies" in the sarcoplasm of skeletal muscle fibers. To date, ACTA1, NEB, TPM3, TPM2, TNNT1, and CFL2 have been found to cause NM. We have identified recessive RYR1 mutations in a patient with severe congenital NM, through high-throughput screening of congenital myopathy/muscular dystrophy-related genes using massively parallel sequencing with target gene capture. The patient manifested fetal akinesia, neonatal severe hypotonia with muscle weakness, respiratory insufficiency, swallowing disturbance, and ophthalomoplegia. Skeletal muscle histology demonstrated nemaline bodies and small type 1 fibers, but without central cores or minicores. Congenital myopathies, a molecularly, histopathologically, and clinically heterogeneous group of disorders are considered to be a good candidate for massively parallel sequencing.

Right-to-left shunting in the ductus arteriosus is induced readily by intense crying and rapid postural change in neonates with meconium-stained amniotic fluid.

OBJECTIVE: To investigate postnatal changes in the direction of blood flow through the ductus arteriosus in neonates with meconium-stained amniotic fluid, we measured preductal and postductal oxygen saturation in normal neonates, neonates with meconium-stained amniotic fluid, and a neonate with persistent pulmonary hypertension of the newborn. DESIGN: Prospective, observational case series report. SETTING: A single, tertiary neonatal intensive care unit. PATIENTS: Twelve normal neonates, seven neonates with meconium-stained amniotic fluid, and a neonate with persistent pulmonary hypertension of the newborn. INTERVENTIONS: SpO2 is simultaneously monitored in the right upper and lower limbs after birth. MEASUREMENTS AND MAIN RESULTS: Compared with normal neonates, three neonates with meconium-stained amniotic fluid required longer than +2 SD of the mean time for the postductal SpO2 to reach 90% and/or 95%. In a neonate with meconium-stained amniotic fluid, intense crying triggered frequent decreases to <70% in the postductal SpO2 from 25 mins after birth, while the preductal SpO2 remained at 95% or above. When the other newborn with meconium-stained amniotic fluid was held in the father's arms after 98 mins, the postductal SpO2 decreased rapidly to <80%, while the preductal SpO2 remained at 95%. Thus, 5% or greater difference between the preductal and postductal SpO2 was observed from 25 mins after birth until 120 mins in all neonates with meconium-stained amniotic fluid, whereas the difference disappeared after 25 mins in 12 normal neonates. In a neonate with persistent pulmonary hypertension of the newborn who required vigorous resuscitation, 5% or greater difference between the preductal and postductal SpO2 levels was observed until 6 hrs after birth. CONCLUSIONS: Right-to-left shunting in the ductus arteriosus may be induced readily by intense crying and rapid postural change in infants with meconium-stained amniotic fluid. It is important to monitor SpO2 at both pre- and postductal regions until 120 mins after birth in neonates with meconium-stained amniotic fluid and to subject these infants to minimal manipulations.

Intratracheal catheter suction removes the same volume of meconium with less impact on desaturation compared with meconium aspirator in meconium aspiration syndrome.

OBJECTIVE: To evaluate the impact of suction technique on the rate of meconium removal, oxygenation, and hemodynamics in an animal experimental model of meconium aspiration syndrome (MAS). METHODS: MAS was induced in ventilated rabbits using 3.5 ml/kg of 20% human meconium. Tracheal suction with either catheter suction (CS) or meconium aspirator (MA) was performed after meconium instillation. Percentage of meconium collection rate, PaO(2) trends for 2h after tracheal suction, and acute-phase SpO(2) trends were compared between CS and the other three groups, the tube was withdrawn while meconium was aspirated with an MA, then the trachea was reintubated 5, 10 or 15s after suctioning of meconium. RESULTS: Percentage of meconium collection rate and PaO(2) showed no significant differences between groups. The MA group taking 15s for reintubation after meconium suctioning, showed a significantly lower acute-phase SpO(2) than the CS group (P<0.05). The time for SpO(2) to return to >or=90% was also longer in the MA group taking 15s for reintubation than in the CS group (P<0.05). CONCLUSION: Intratracheal CS removed the same volume of meconium with less impact on desaturation compared with meconium aspiration in an animal model of MAS. Intratracheal CS may be benefit to remove meconium in non-vigorous infants with meconium-stained amniotic fluid at birth.