There had been many studies demonstrated that the phosphodiesterase inhibitor pentoxifylline (PTX) is a potent anti-inflammatory, anti-proliferative, and anti-fibrotic agent capable of attenuating experimental renal disease such as drugs, ischemic and sepsis induced AKI. We thus hypothesized that PTX may have therapeutic value for AKI in human. We thereby design this controlled, non-randomized clinical trial, aiming at investigating the potential renoprotective efficacy of PTX, as compared to placebo, in 200 patients with AKI.