IGFBP7 and acute kidney injury: Six studies (n = 350) were conducted to evaluate the diagnostic value of urinary [TIMP-2] x [IGFBP7] for AKI after major surgeries (5 cardiac surgery [13, 14, 16–18] and 1 non-cardiac surgery [15]), and four studies (n = 1298) were conducted among ICU patients [11, 12, 19, 20].