“…It is well known that the so called renal functional reserve, in healthy subjects, must be exhausted before serum creatinine increases (11,20). Since creatinine has a much lower sensitivity than other recently identified biomarkers, it could be supposed that different methods of investigation, could have revealed renal reserve reduction, otherwise missed by the simple creatinine rise (21). In fact, some novel biomarkers appear to be positive even in to "subclinical AKI" where creatinine does not increase (22,23).…”