Prospective, multicenter, spontaneous, non-interventional, non pharmacological. Study aimed at evaluate kinetics, diagnostic and prognostic value of pro-ADM (proadrenomedullin) as compared to PCT (procalcitonin) in patients presenting with infections or other complications post hematopoietic stem cell transplantation (HSCT)

Evaluation of diagnostic performance of pro-ADM as compared to palliative care therapy (PCT) in paediatric and young adult patients with any type of complications after hematopoietic stem cell transplantation or with transplant related complications.

Inclusion Criteria:

• Written informed consent of the parents/legal guardians and patient's assent/consent according to national regulations. For subjects who turn 18 years of age during participation in this study, participation in the future use portion of the study after their 18th birthday requires that they sign the informed consent statement following turning 18 years of age.
• Age at time of registration from 28 days to less than 39 years of age.
• Malignant disease (i.e. Acute lymphocytic leukemia (ALL), Acute myeloid leukemia (AML), Myelodysplastic syndromes (MDS)) or nonmalignant disease (e.g. immunodeficiency or inherited disorders of metabolism or hemoglobinopathies etc.) indicated for allogeneic HSCT.

Exclusion Criteria:

• Age less than 28 days
• Obese patients with body mass index: > 30 kg/m^2.
• Impaired cardiac function: severe cardiac insufficiency indicated by left ventricle ejection fraction (LVEF) ≤ 35%.
• Impaired liver function indicated by Bilirubin >3 times the upper limit of normal (ULN), or aspartate aminotransferase/alanine aminotransferase (AST/ALT) >10 times ULN
• Impaired renal function indicated by estimated glomerular filtration rate (GFR), according to the Schwartz formula for ages 1-17 and according to CDKEPI creatinine equation for ages above 17 years old) < 60 mL/min/1,73m^2.
• Concurrent severe active infection at the start of conditioning regimen

Pediatric and young adult patients affected by malignant or non-malignant disorders referred for HCST