טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentKeren Rinat
SubjectExpression of Surfactant Proteins in Newborn Infants
with Respiratory Distress Syndrome (RDS)
DepartmentDepartment of Medicine
Supervisors Mr. Zalman Weintraub
Dr. Miriam David
Assistant Professor Fuad Fares


Abstract

Deficiency of pulmonary surfactant is the principle cause of neonatal Respiratory Distress Syndrome (RDS). A major complication of RDS is Bronchopulmonary Dysplasia (BPD). Inability to produce surfactant protein B (SP-B) causes lethal RDS. A common SP-B mutation is the 121ins2. It was found on both alleles in approximately two thirds of SP-B-deficient patients due to early termination of translation. Recently, a 122delT mutation in SP-B gene was found associated with RDS. Polymorphism of the SP-A gene may also related to RDS. Our study examines the relationship between SP-A and SP-B levels to gestational age, RDS severity and later development of BPD. We also screened for mutations in SP-B gene in neonates in Israel.

The study population consisted of 60 preterm infants and 8 term infants. SP-A and SP-B levels were measured in bronchial lavage using ELISA. 121ins2 and 122delT mutations in SP-B gene were screened in patients who had low levels of SP-B. There was no correlation between SP-A and SP-B levels to gestational age (GA). However, in the group of infants born later than 28 weeks gestation there was some correlation between GA and SP-A levels only. In infants below 28 weeks gestation, there was inverse correlation between SP-B levels and GA. Only in infants with birth weight above 1000 g. SP-A and SP-B correlated directly with birth weight. The proteins levels increased slightly during the first 5-10 days. Higher levels of SP-A and SP-B were related to lower Mean Airway Pressure. No correlation was found between the initial proteins levels and the incidence and severity of BPD. No mutations in SP-B gene were found in the 8 term infants with severe RDS.