Van Der Heggen, et al. - This pilot study aimed at determining the incidence and risk factors of hyperfiltration in a paediatric intensive care setting. Additionally, researchers performed a comparison of different methods for glomerular filtration rate (GFR) assessment in critically ill children. They realized common occurrence of hyperfiltration in critically ill children. The modified Schwartz formula seemed to underestimate GFR in case of hyperfiltration. Cystatin C appeared a promising alternative renal biomarker but required further investigation.