<qa>  What is Ketosteril?This study will evaluate patients who have an episode of moderate to severe acute kidney injury AKI and are followed in a focused post-AKI clinic. After patients present signs of kidney recovery and before hospital discharge, patients who give consent will be enrolled in the study. At the first post-AKI clinic visit, patients will be randomly allocated to follow a normal ad-lib or a low protein diet LPD for 3 months. Patients allocated to a LPD will receive a drug called Ketosteril. This drug allows the intake of essential amino acids while minimizing the amino-nitrogen intake, what in excess, can be bad for the recovered kidney. The investigators will evaluate the nutritional parameters and the kidney recovery of all patients and compare these parameters in those two groups. 