Is chlorine and sodium levels in the amniotic fluid a new marker for fetal lung maturation and RDS severity?

BACKGROUND: Amniotic fluid (AF) is a dynamic liquid whose contents vary according to the needs of the fetus. Levels of the amniotic components have been used in numerous studies as potential biomarkers to screen pregnancy-related abnormalities. As a reflection of Na+ and Cl- levels of fetal lung fluid, amniotic fluid's Na+ and Cl- levels can be used as an indicator of lung maturation in the newborn period. This study aimed to investigate whether Na+ and Cl- levels in the amniotic fluid would be a new marker to determine the severity of respiratory distress and pulmonary maturation in the newborn. METHODS: This prospective cohort study was conducted at Hacettepe University Neonatal Intensive Care Unit. One hundred twenty single infants who were delivered with the cesarean section between January 2015 and March 2016 were included. Na+ and Cl- levels were measured from AF. RESULTS: There were 46 of 120 infants (33.3%) in Group-1 and 74 infants (66.7%) in Group-2. Na + and Cl- levels of the AF of Group-1 were higher than Group 2 and this was statistically significant (p < .001/p: .01, respectively). Na+ and Cl- levels of the AF were significantly higher in infants who needed surfactant (p < .001/p: .001, respectively). CONCLUSION: Our results showed that Na+ and Cl- levels of the AF can be used as an indicator of infant lung maturation.

A novel NKX3-2 mutation associated with perinatal lethal phenotype of spondylo-megaepiphyseal-metaphyseal dysplasia in a neonate.

Spondylo-megaepiphyseal-metaphyseal dysplasia (SMMD) is an autosomal recessive skeletal dysplasia, characterized by disproportionate short stature with a short and stiff neck and trunk. SMMD is caused by inactivating mutations in NKX3-2, which encodes a homeobox-containing protein. Because of the rarity of the disorder, the diagnostic feature has not been fully established yet. We describe an affected newborn with dysmorphic facial features and severe short trunk. The patient required immediate intubation at the delivery room and duodenal atresia was detected during his course in neonatal intensive care unit. Skeletal survey revealed total absence of the ossification of the vertebral bodies, pubis, and ischia. Mainly the femora was short and broad with mild flaring of the metaphyses. The downward sloping or tented appearance of the ribs was distinctive. A diagnosis of SMMD was made on clinical and radiological grounds. Molecular analysis revealed homozygosity for a novel mutation, c.507-508delCA (p.Gly171Cysfs*55) in exon 2 of NKX3-2. The patient was operated on postnatal day 7 for duodenal atresia. In the post-operative period he developed sepsis and respiratory failure and he died on postnatal day 14. Although no neuroradiologic imaging could be performed, the findings of clubfoot, neuromuscular respiratory insufficiency requiring invasive mechanical ventilation and downward sloping or tented appearance of the ribs were suggestive of very early cervical cord compression leading to perinatal mortality. To our knowledge this patient yet represents one of the most severe postnatal phenotypes of SMMD.