title: Serum immunoglobulin G levels and peritonitis in peritoneal dialysis patients.
abstract: BACKGROUND
  Peritonitis is a frequent and serious complication of peritoneal dialysis (PD). Whether low immunoglobulin level is associated with PD-related peritonitis is unknown.
  
  
  METHODS
  We conducted a prospective study to assess whether immunoglobulin levels at PD onset could predict the occurrence of peritonitis. All patients starting peritoneal dialysis between 01/2005 and 12/2010 at the University hospital of Besançon, France, were included in the study.
  
  
  RESULTS
  Of 240 consecutive PD patients enrolled (mean follow-up 25 ± 12 months), 76 (32%) had at least one episode of peritonitis. Mean immunoglobulin (Ig)G level at PD start was lower in patients who subsequently experienced peritonitis (7.9 + 3.4 vs. 9.7 + 3.4 g/l, p = 0.005). An increased IgG level at PD onset was associated with a reduced risk of peritonitis [hazard ratio (HR) 0.88, 95% confidence interval (CI) 0.80-0.97 for each increase of 1 g/l in IgG, p = 0.008]. IgG level ≤6.4 g/l ("low IgG") was the best predictive value for the occurrence of subsequent peritonitis: 52 patients (24%) had low IgG levels. At multivariate analysis, both low IgG level (HR 2.49, 95% CI 1.32-4.69, p = 0.005) and diabetes (HR 2.78, 95% CI 1.49-5.20, p = 0.001) were predictive of the occurrence of peritonitis.
  
  
  CONCLUSIONS
  Low IgG levels predict the occurrence of PD-related peritonitis. Randomized studies should determine whether such patients could benefit from intravenous immunoglobulin administration.
authors.affiliation: INSERM UMR1098, Fédération Hospitalo-Universitaire INCREASE, 25020, Besançon, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Courivaud
authors.forename: Karine
authors.initials: K
authors.lastname: Bardonnet
authors.forename: Thomas
authors.initials: T
authors.lastname: Crepin
authors.forename: Catherine
authors.initials: C
authors.lastname: Bresson-Vautrin
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Rebibou
authors.forename: Didier
authors.initials: D
authors.lastname: Ducloux
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D015536:Down-Regulation; D005260:Female; D005602:France; D006785:Hospitals, University; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000009:adverse effects* / Q000401:mortality; D010538:Peritonitis / Q000097:blood / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality / Q000628:therapy; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D007074:Immunoglobulin G