The methionyl-tRNA synthetase (MARS) mutation is a very rare cause of congenital pulmonary alveolar proteinosis. We report a 6-month-old boy born with symmetrical intrauterine growth retardation presented with unexplained persistent tachypnea and hypoxemia associated with severe failure to thrive, anemia, hypoalbuminemia and hepatomegaly. Detailed pulmonary investigations including computed tomography chest scan, bronchoscopy and bronchoalveolar lavage revealed pulmonary alveolar proteinosis. Whole exome sequencing identified a homozygous novel variant in the MARS gene, c.854T>C p.(Ile285Thr).

Objectives:To assess the respiratory syncytial virus (RSV) infection incidence rate through the analysis of data collected before and after implementation of a new palivizumab dosing regimen customized for a high-risk Saudi population.Methods:This was a retrospective cohort study performed at Prince Sultan Military Medical City, Riyadh, Saudi Arabia between November 2009 andApril 2017 on 1704 high risk Saudi young children and comparing 3 palivizumab regimens: a 4-week interval dosing regimen starting in either November or mid-September and a 3-week interval dosing regimen starting in mid-September.Results:Despite a decrease in the incidence rate of RSV infection with the three-week interval regimen (3.9% versus 5.9% in seasons 1 and 9.1% in seasons 2), we did not find significant differences among the 3 groups.Conclusion:Expanded use of palivizumab in newborn children could improve outcomes, but further investigation and a careful cost analysis are required.