without any evidence of damage [24]. Urinary excretion of KIM-1 has been shown to be an independent predictor of long-term graft dysfunction after kidney transplant [26]. However, evidence for its use in screening people with CKD is lacking. Other markers may prove useful as therapeutic targets, diagnostic tests or prognostic tools to help prevent kidney damage [27, 28] but they are beyond the scope of the present editorial. Accurate assessment of renal function is essential especially in those at high risk of deve- loping CKD, both young and old. Screening indi- viduals with the available prediction equations has limitations. New markers of kidney injury such as NGAL hold hopes for improved prediction of renal function independently of age, ethnicity, gender, muscle mass and body fat. More studies are needed to assess the influence of ethnicity, various drugs and changes in body composition in relation to this marker. 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