Kidney (Renal) failures occur mostly due to dehydration, excessive intake of synthetic medicines, diabetes mellitus, irregular blood pressure, etc.

Chronic Kidney Disease is divided into 5 stages depending on the Glomerular Filtration Rate (GFR). The following table shows the stages of Kidney Diseases indicated by the GFR and how it is managed

Stages 1 90 or above Kidney damage with normal or high GFR The cause of Kidney damage is detected early and treatment begins. It is important to manage other problems such as Diabetes and Hypertension.
Stages 2 60-89 Kidney damage with slightly lower GFR The doctor estimates how quickly Kidney Disease progresses. Diabetes and Hypertension will need to be kept under control by regularly monitoring it.
Stages 3 30-59 Kidney damage with moderately low GFR The doctor usually checks for Anemia. The treatment begins at this point.
Stages 4 15-29 Kidney damage with severely low GFR The doctor and you will have to come to a decision as to which treatment would be preferable in the event of a kidney failure. The doctor will monitor your health condition closely.
Stages 5 <15 Kidney failure You will have to start dialysis or have to go through kidney transplant. You will also have to regularly see your doctor for treatment or have consultation.