Renal insufficiency is divided into two categories: acute and chronic, with different pathogenic factors, as follows: 1. Chronic renal insufficiency: common acute nephritis, chronic nephritis; diabetic nephropathy, gouty nephropathy, hypertensive nephropathy, and obstructive nephropathy; also seen in hematologic-related nephropathy, multiple myeloma, nephropathy due to dry syndrome; 2. Acute renal insufficiency: common glomerular, tubular, drug, renal vascular factors leading to renal function impairment. Also seen in prerenal factors, including severe infection, shock; postrenal factors including stones, prostate hypertrophy, etc. can lead to renal failure.