Rubin Z, et al. - Researchers, herein, focused on the epidemiology as well as characterization of the clinical outcomes of children hospitalized with primary immunodeficiency disease (PIDD) in the United States. Findings suggested a possible over time increase in the prevalence of PIDDs in the hospitalized pediatric population in the United States. Data also reported an association of younger age with higher mortality, hospital costs, and length of stay.