Clinical significance of peritoneal dialysate IgG levels in CAPD patients

To assess the normal range and the clinical significance of peritoneal IgG, the levels of these proteins were measured in 24 hour dialysates of 69 patients. The mean + SD of IgG levels was 7.2 +/- 4.3 mg/dl. Two patients had peritoneal IgG concentrations below and 6 above the mean +/- SD range. There were no significant correlations between peritoneal IgG levels and sex, previous hemodialysis, age, time of dialysis, number of peritonitis or estimated daily protein intake. In 29 of these patients dialysate IgG levels measured again one year later did not show significant differences between the first and the second determination of IgG (from 6.3 +/- 3.3 to 6.6 +/- 3.2 mg/dl), but changes of 10% or more were observed in 14 of these patients. Our data show no relation between peritoneal IgG and peritonitis episodes. Therefore by these results dialysate IgG cannot be used as a reliable index to decide which patients are at high risk for peritonitis.