1. From the Department of Neonatology, Medical Academy, Warsaw, Poland; the Pediatric Intensive Care Unit, Medical Academy Children's Hospital, Warsaw, Poland; the Immunology and Microbiology Department, The Children's Memorial Health Institute, Warsaw, Poland; the Hospital Pharmacy of Princess Anna Mazowiecka Hospital, Warsaw, Poland; and the Immunology Department, Rydygiers's Medical Academy, Bydgoszcz, Poland.