All subjects included into this study will undergo routine examination upon admission to the hospital. These examinations include physical, medical/medication history (on the last year for medical history and the last 3 months for medication history (if available)), vital signs, radiologic data and laboratory tests. Assessment of these data will occur in potential candidates within 24 hours of their hospitalization. BMI (Body Mass Index) will be derived from the subjects' height and weight. PIM 2 and PELOD scores will be computed (the PIM 2 score is a mortality risk score for children, and the PELOD score is a scale estimating the severity of cases of multiple organ).