Chronic Kidney Disease (CKD) is defined as the gradual loss of kidney function and structural damage. There are many different causes leading to kidney disease, which will be reviewed in the next section. Kidney disease can be categorized into five stages depending on the remaining level of function or how severe the damage is to the kidneys. Based on the cause of your underlying kidney disease, the function may decrease gradually over many years without any physical symptoms. Not every person progresses through all the stages.
The last stage of kidney disease is called End Stage Renal Failure (ESRF). At this point, the remaining function of the kidney is too low to meet the physiological need to remove water and waste products from the body. It is at this point that patients usually develop signs, also described as symptoms, such as edema (swelling), shortness of breath, fatigue, loss of appetite, nausea and vomiting, and eventually changes in mental status and heart function. At this stage, renal replacement therapy is initiated by the physician.