Kandasamy Y, et al. - In this longitudinal cohort study, researchers sought to measure serial CysC (Cystatin C) in a cohort of neonates born preterm until the age of 2 years. They tested the assumption that CysC levels are independent of body weight and would not vary with gestational age. This investigation was carried out from August 2014 until October 2016 and follow up was completed in October 2018. They involved preterm infants at less than 28 weeks of gestation (extremely preterm infants) and followed up until the age of 24 months. The sample consisted of 58 preterm neonates with mean gestation was 26.2 (1.5) weeks, and a mean birth weight was 917 (140) g. Despite a significant increase in body weight, one‐way analysis of variance did not display any significant difference in CysC levels between 28, 32‐ and 37‐weeks' gestation. In the neonatal period, the mean CysC level was higher and subsequently plateaued by 24 months. Serum CysC level is not affected by postnatal age or gender, irrespective of body weight.