<prompt> Answer this question truthfullyWhat are the different stages of chronic kidney disease CKD and what are the corresponding ranges of glomerular filtration rate GFR?  <response>: <reason> The stages of CKD are as follows: Stage I - NormalHigh: GFR 90, Stage II - Mild: GFR 60-89, Stage III - Moderate: GFR 30-59, Stage IV - Severe: GFR 15-29, Stage V - Kidney failure: GFR 15. 