Four demographic factors, including age, BMI, sex, diabetes, and dialysis age; 10 local environmental factors, including the shower interval, last shower time, suture, cover, secretion, granulation, itchiness, last disinfection, redness, and catheter service time; and fifteen systemic biochemical factors, including transferrin saturation, RBC, hemoglobin, Hct, serum iron, transferrin, calcium, phosphates, PTH, albumin, pre-albumin, Cr, BUN, CRP, and β2m, were tested for their correlation with the skin microbiota components in the network analysis. Here, B2M is linked to diabetes mellitus.