title: Peritonitis, peritoneal inflammation and membrane permeability: a longitudinal study of dialysate and serum MCP-1 in stable patients on peritoneal dialysis.
abstract: BACKGROUND
  Increase in peritoneal membrane permeability (D/P) correlates with systemic and peritoneal markers of inflammation and neoangiogenesis. Monocyte chemoattractant protein-1 (MCP-1, CCL2) is a potent chemoattractant and activator of monocytes/macrophages. We measured the serum (sMCP-1) and dialysate MCP-1 (dMCP-1) concentrations of stable peritoneal dialysis (PD) patients and studied various factors affecting MCP-1 production. We also looked at the correlation of dMCP-1 concentrations with change in D/P over 12 months.
  
  
  METHODS
  Forty-five stable prevalent and 6 new PD patients (22 CAPD, 29 APD) were studied. Median PD duration was 21 months (range 1-114). D/P was measured by standardized peritoneal equilibration test (PET). Patients with recent peritonitis within 3 months of the start of study were excluded. MCP-1 concentrations were measured in serum, overnight dialysate and post-PET dialysate, both at baseline and at 12 months by ELISA.
  
  
  RESULTS
  On univariate analysis, post-PET dMCP-1 concentrations positively correlated with sMCP-1 (p=0.0002), duration of PD (p=0.02), dialysate volume (p=0.001), peritoneal creatinine clearance (p=0.0002) and D/P (p=0.001). There was a negative correlation with residual renal function (p=0.001). dMCP-1 concentrations were higher in patients with past peritonitis (p=0.001). On multivariate analysis, factors independently associated with dMCP-1 were sMCP-1 (p=0.003) and past peritonitis (p=0.001). Thirty patients completed this study, and D/P rose by > 0.1 in 20% patients. dMCP-1 concentrations were higher in baseline and 12-month samples in patients with change in D/P >0.1.
  
  
  CONCLUSIONS
  We conclude that dMCP-1 concentrations are related to past peritonitis and serum MCP-1. It is difficult to interpret the relationship of dMCP-1 with change in D/P over time due to the small number of patients.
authors.affiliation: Renal Department, Charing Cross Hospital, London - UK. armalik@ntlworld.com
authors.forename: Amir R
authors.initials: AR
authors.lastname: Malik
authors.forename: Mark A
authors.initials: MA
authors.lastname: Little
authors.forename: Marie
authors.initials: M
authors.lastname: Henriksson
authors.forename: Frederick W K
authors.initials: FW
authors.lastname: Tam
authors.forename: Edwina A
authors.initials: EA
authors.lastname: Brown
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018932:Chemokine CCL2 / Q000032:analysis* / Q000097:blood; D005260:Female; D015312:Hemodialysis Solutions / Q000737:chemistry*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis; D010537:Peritoneum / Q000378:metabolism*; D010538:Peritonitis / Q000097:blood* / Q000378:metabolism*; D010539:Permeability
chemical_list: C111835:CCL2 protein, human; D018932:Chemokine CCL2; D015312:Hemodialysis Solutions