PERITONEAL DIALYSATE IGG C3 LEVELS DO NOT PREDICT SUSCEPTIBILITY TO PERITONITIS/

Objective: To investigate the usefulness of dialysate IgG and C3 conce ntrations in predicting likelihood of developing peritonitis. Design: Prospective, longitudinal, and comparative study. Setting: Single univ ersity teaching hospital dialysis unit and outpatient clinic. Patients : Thirty-four uremic patients were studied (20 males, 14 females: mean age 47.2, range 20 - 73 years). Monthly serum and overnight dialysate (eight- to eleven-hour dwell) samples were obtained for IgG and C3 es timations over the first six months of the study, and trimonthly sampl es were obtained thereafter. All patients performed exchanges using st andard transfer sets (Baxter system II, Baxter Healthcare Ltd., Thetfo rd, Norfolk, U.K.), used no hypertonic fluid (3.86%) for overnight exc hanges, and were followed up for a minimum of 18 months. Outcome Measu res: Dialysate and serum levels of IgG and C3; peritonitis episodes. R esults: Forty-five episodes of peritonitis occurred in 24 patients dur ing the study period. We examined opsonin levels in the group as a who le, and then in two subgroups of patients: those who remained peritoni tis-free throughout the study, and those who did not. There were no si gnificant differences between IgG and C3 levels in the two groups al a ny time point, and large interpatient and intrapatient variation in le vels were seen. Conclusion: Dialysate levels of IgG acid C3 from the o vernight dwell are not helpful in predicting the risk of developing co ntinuous ambulatory peritoneal dialysis peritonitis in individual pati ents. No correlation was found between opsonin levels and onset of cli nical peritonitis.