The severity of nephritis varies from one kidney infection to another. If left untreated, the life expectancy of patients ranges from a few months to decades. If the nephritis is mild, such as for simple hematuria without urine protein or abnormal kidney function, patients do not even need to take medication at this time, and their life expectancy is the same as normal people and will not be greatly affected. If the urine protein quantification is less than 3.5 grams and the kidney function is normal, some patients can heal themselves if they are not treated; however, the majority of patients will have a slow decline in kidney function, and a small number of patients will progress to uremia within a few decades. If the urine protein quantification is greater than 3.5 grams or the kidney function is already abnormal, without active treatment, patients will progress to uremic syndrome within a few years. At present, the level of medical technology has improved greatly compared to the previous level, even patients with uremia can survive for more than 10-20 years if they are treated with active dialysis. If uremic patients remain untreated aggressively, life-threatening conditions may occur at any time.