Long Term Renal Function After CRRT in the Paediatric Intensive Care Unit, a Follow-up Study.

In this study the investigators will evaluate the long-term renal function in children treated with continuous renal replacement therapy (CRRT) due to acute kidney injury (AKI) and multiple organ failure (MOF) in the pediatric intensive care unit (PICU). These children are not always referred for nephrology follow up after their ICU stay and it is unclear to what extent the patients suffer from chronic renal disease. The primary aim is to establish the frequency of chronic kidney disease (CKD) in children treated with CRRT due to AKI. Secondary outcomes will include mortality, frequency of end stage-renal disease (ESRD) and need for hemodialysis and/or renal transplantation.

Inclusion Criteria:- Age newborn to 18 when admitted to ICU. CRRT treatment 2008-2021 due to AKI stage ≥ stage 1 (according to KDIGO) and/or ≥ 2 organ failuresExclusion Criteria:CRRT due to metabolic and/or endocrinologic comorbidity.Chronic renal failure before CRRT.Previous renal transplantation.Prospective part:- Not a resident of Stockholm County and no planned follow up at Karolinska University Hospital.Retrospective part:- Patient referred to Karolinska University Hospital from a hospital outside Sweden.