Study of the Intermediate Metabolism in Children With Acute Lymphoblastic Leukemia (ALL)

* Sex: all * Minimum age: 1 year * Maximum age: 16 years * The study accepts healthy volunteers as matched controls for the patinets. * Inclusion criteria: 1)Children diagnosed with ALL 2) Diagnosis confirmed with bone marrow biopsy 3) Sampling before the initiation of therapy 4) Informed consent signed * Exclusion Criteria: 1) Children with a known chronic illness before ALL diagnosis 2) ALL remission 3) Not signed informed consent * Population description: Patients are recruited from the Pediatric Hematology/Oncology Department of Aristotle University of Thessaloniki (AHEPA hospital) and from the Pediatric Hematology/ Oncology Department of Ippokration Hospital, that host all children diagnosed with ALL in nothern Greece. Matched controls are recruited from outpatient clinic of the 2nd and 4th Pediatric Department of Aristotle University of Thessaloniki. * Sampling method: Non-probability sample