Progression Of Respiratory Distress Syndrome Research Articles

Evaluation of the Copy Number Variants and Single-Nucleotide Polymorphisms of ABCA3 in Newborns with Respiratory Distress Syndrome-A Pilot Study.

Background and Objectives: Respiratory distress syndrome (RDS) in preterm infants commonly occurs due to the immaturity-related deficiency of pulmonary surfactant. Beyond prematurity, various environmental and genetic factors can influence the onset and progression of RDS. This study aimed to analyze three single-nucleotide polymorphisms (SNPs) of the ABCA3 gene to assess the ABCA3 gene as a candidate gene for susceptibility to RDS and overall survival in newborns and to evaluate the utility of MLPA in RDS neonatal patients. Materials and Methods: Three SNPs were chosen and genotyped in a cohort of 304 newborns. Data analysis and statistical tests were employed to examine allele frequencies, haplotypes, and measures of pairwise linkage disequilibrium. Results: There was no observed haplotype association with SNPs rs13332514 (c.1059G>A) and rs170447 (c.1741+33T>C) among newborns, both with and without RDS (p > 0.05). The minor C allele frequency of the ABCA3 rs323043 (c.1755G>C) SNP showed a significant increase in preterm infants with RDS. MLPA results indicated that the predominant findings were normal, revealing no CNVs in the genes ABCA3 and SFTPC that were investigated in our patients. Conclusions: The presence of the variant C allele in the rs323043 (c.1755G>C) SNP may be a risk factor for RDS in premature newborns.

An Audit of Management of Respiratory Distress Syndrome in the Context of the 2007 European Consensus Guidelines

Background and aims: To audit compliance and variation in management of neonatal respiratory distress syndrome (RDS) in an era post publication of the 2007 European Consensus Guidelines. Methodology: Retrospective review of inborn preterms less than (< )37 weeks with RDS for the period from January 1st 2008 to December 31st 2008. Results: Of 197 infants, 29(14.72%) infants were < 27 weeks, 31(15.74%) between 27 to < 30 weeks, 91(46.19%) between 30 to < 34 weeks, and 46(23.35%) between 34 to < 37 weeks. All infants< 27weeks received surfactant, administered before 15mins in 28 of 29 infants. 80.65% infants in the 27 to < 30 weeks age group received surfactant, in comparison to 37.36%of infants between 30 to < 34 weeks, and 15.22% infants between 34 to < 37 weeks. Prophylactic surfactant was administered in 58% of infants between 27 to < 30 weeks age group. This did not correlate with the use or non-use of prenatal steroids. Only 1 of 29 infants < 27 weeks was immediately extubated post-surfactant. Timing of surfactant re-dosing was variable and initiated at a higher mean FiO266% and alveolar-arterial ratio 0.14 in prohylaxed infants < 27 weeks compared to rescue/re-dosing surfactant at mean FiO2 48% in infants between 27 to < 30 weeks. Conclusions: Overall compliance was achieved in prophylactic surfactant administration in infants < 27 weeks. For babies more than 27 weeks, significant variation was demonstrated in management strategies. This practice variation prompts generation of a unit policy of when to intervene with progression of RDS.

High Expression of Pulmonary Proteinase-activated Receptor 2 in Acute and Chronic Lung Injury in Preterm Infants

Proteinase-activated receptor 2 (PAR(2)), a G-protein-coupled receptor activated by serine proteinases such as trypsin, has been suggested to play an important role in inflammatory and fibroproliferative processes. In preterm infants, the development of bronchopulmonary dysplasia (BPD) is characterized by early pulmonary inflammation and subsequent interstitial fibrosis. High pulmonary trypsin-2 has been shown to be associated with the development of BPD. We studied the expression and distribution of PAR(2) and trypsin-2 by immunohistochemistry in autopsy lung specimens of fetuses (n = 10), of preterm infants who died of acute or prolonged respiratory distress syndrome (RDS) (n = 8 and n = 7, respectively) or BPD (n = 6), and of newborn infants without lung disease (n = 5) who served as controls. In prolonged RDS and BPD, PAR(2) immunoreactivity was significantly higher in bronchial epithelium when compared with infants without pulmonary pathology (p < 0.05 and p < 0.005, respectively). In alveolar epithelium, expression of PAR(2) was elevated in prolonged RDS when compared with newborn infants without pulmonary pathology (p < 0.05). Moreover, strong expression of PAR(2) was detected in myofibroblasts of thickened and fibrotic alveolar walls in prolonged RDS or BPD. Trypsin-2 was co-localized with PAR(2) in bronchoalveolar epithelium. These findings suggest that PAR(2), possibly activated by trypsin-2, may participate in inflammation and fibroproliferation associated with progression of RDS toward BPD in preterm infants.