1. Division of Paediatric Surgery; Department of General-Visceral and Transplant Surgery; University Hospital; University Duisburg-Essen; Essen Germany
2. Children's Hospital; Klinik 2; Duisburg-Essen; Essen Germany
3. Institute of Medical Microbiology; University Hospital; University Duisburg-Essen; Essen Germany
4. Department of General-Visceral and Transplant Surgery; University Hospital; University Duisburg-Essen; Essen Germany