GSTM1 and peritonitis: 1. Incidence of complications: peritonitis incidence, catheter outlet infection rate, tunnel infection rate, hospitalization rate2. Daily record of indicator changes: weight. Bmi. Blood pressure, Ultrafiltration, Urine Volume3. Test indicators: Hemoglobin (Hb), Albumin (Alb), hemoglobin (HB), albumin (ALB),Serum creatinine (Scr), Calcium (Ca), Phosphorus (P), serum Creatinine (SCR),Blood urea nitrogen (BUN), Intact parathyroid hormone (iPTH) and urea clearance (Kt/V) indicators