All patients starting PD as the first dialysis treatment will be considered. Recruitment will take place over a six-months period in hospitals belonging to the Instituto Mexicano de Seguro Social. Inclusion criteria include: adult patients with signed informed consent given; there should not be selection for age, gender, primary cause of renal disease. Patients will not be included if they were previously in hemodialysis or received renal transplant. Patients will also be excluded if they are on immunosuppressive therapy, have diagnosis of cancer, or are seropositive for HIV or hepatitis.