Association of SP-B gene 9306 A/G polymorphism (rs7316) and risk of RDS.

BACKGROUND: Respiratory distress syndrome (RDS) is a severe pulmonary disease predominantly affects preterm newborns. Polymorphisms of surfactant-protein genes have been mostly evaluated as the candidate contributors in genetics of RDS. However the results are divers in different studies. We aimed at investigating the association of surfactant protein B (SPB) gene 9306 A/G polymorphism (rs7316) with RDS development. METHOD: Three hundred and eighty newborns with gestational age of less than 34 weeks were included in a multicenter case-control study. Respiratory distress (RD) was scored according to Downes' scoring system. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used for genotyping. RESULT: One hundred and eighty-four neonates showed RDS and 196 did not. Gestational age (GA) was significantly lower in the RDS group compared with the controls. AA genotype and A allele were found more frequently in the RDS group than the controls (96.2% versus 63.8% and 98.1% versus 80.6%, respectively) (p =.0001). CONCLUSIONS: This is the first report of association of SFTPB rs7316 polymorphism with RDS development in Iranian newborns. The current study suggests that GA <28-weeks is the most important factor in predisposition to RDS. Genetic background in terms of SP-B gene might be involved in predisposition to RDS in premature neonates.

Association of SP-C gene codon 186 polymorphism (rs1124) and risk of RDS.

BACKGROUND: Respiratory distress syndrome (RDS) is a severe pulmonary disease that mainly affects preterm neonates. Surfactant-protein genes' polymorphisms have been mostly evaluated as the candidate contributors in genetics of RDS. However, the results are diverse in different populations. We aimed at investigating the association of rs1124 with RDS development. METHOD: Three hundred and thirty five preterm neonates were enrolled in a multicenter case-control study. Respiratory distress (RD) was scored according to Downes' scoring system. Genotyping was performed by PCR-RFLP method. RESULT: One hundred and sixty six neonates showed RDS and 169 did not. Gestational age (GA) was significantly lower in RDS group compared to the controls. In female preterm newborns, AA genotype was found more frequently in RDS group. In RDS group, AA genotype was also associated with milder RD irrespective of gender. In neonates who were born 28-34 weeks, RD appeared to be more severe in the RDS group and males. CONCLUSIONS: This is the first report of association of SFTPC rs1124 polymorphism with RDS development in Iranian newborns. The current study suggests that GA <28-weeks is the most important factor in predisposition to RDS. AA genotype is also, a predisposing factor for the development of RDS in female preterm infants.

Comparison of INSURE method with conventional mechanical ventilation after surfactant administration in preterm infants with respiratory distress syndrome: therapeutic challenge.

Administration of endotracheal surfactant is potentially the main treatment for neonates suffering from RDS (Respiratory Distress Syndrome), which is followed by mechanical ventilation. Late and severe complications may develop as a consequence of using mechanical ventilation. In this study, conventional methods for treatment of RDS are compared with surfactant administration, use of mechanical ventilation for a brief period and NCPAP (Nasal Continuous Positive Airway Pressure), (INSURE method ((Intubation, Surfactant administration and extubation)). A randomized clinical trial study was performed, including all newborn infants with diagnosed RDS and a gestational age of 35 weeks or less, who were admitted in NICU of Valiasr hospital. The patients were then divided randomly into two CMV (Conventional Mechanical Ventilation) and INSURE groups. Surfactant administration and consequent long-term mechanical ventilation were done in the first group (CMV group). In the second group (INSURE group), surfactant was administered followed by a short-term period of mechanical ventilation. The infants were then extubated, and NCPAP was embedded. The comparison included crucial duration of mechanical ventilation and oxygen therapy, IVH (Intraventricular Hemorrhage), PDA (Patent Ductus Arteriosus), air-leak syndromes, BPD (Broncho-Pulmonary Dysplasia) and mortality rate. The need for mechanical ventilation in 5th day of admission was 43% decreased (P=0.005) in INSURE group in comparison to CMV group. A decline (P=0.01) in the incidence of IVH and PDA was also achieved. Pneumothorax, chronic pulmonary disease and mortality rates, were not significantly different among two groups. (P=0.25, P=0.14, P=0.25, respectively). This study indicated that INSURE method in the treatment of RDS decreases the need for mechanical ventilation and oxygen-therapy in preterm neonates. Moreover, relevant complications as IVH and PDA were observed to be reduced. Thus, it seems rationale to perform this method as the initial treatment for neonates with mild to moderate RDS.