Dialysate markers of peritoneal tissue during peritonitis and in stable CAPD.

OBJECTIVE

To investigate whether dialysate concentrations of substances that are locally produced within the peritoneal cavity can be used to study the effects of inflammation on peritoneal tissue.

DESIGN

We followed the appearance rates (AR) of concentrations of cancer antigen (CA) 125, phospholipids (PHL), hyaluronan (HA), and the procollagen peptides PICP (procollagen 1 C-terminal) and PIIINP (procollagen 3 N-terminal) in dialysate during peritonitis (8 consecutive days) and after recovery. Data were compared with the stable situation.

SETTING

CAPD (continuous ambulatory peritoneal dialysis) unit in the Academic Medical Center in Amsterdam.

PATIENTS: Twelve CAPD patients with a total of 16 episodes of peritonitis and 10 clinically stable CAPD patients were studied.

RESULTS

All substances showed temporal increments in dialysate during peritonitis compared to control. No difference was found between the control day of peritonitis and the stable patients. Maximum AR were reached in the acute phase of peritonitis for CA125, PHL, and HA and on day 4 for both PICP and PIIINP. A second increment in CA125 occurred on days 4 to 6. These findings indicate acute damage to the mesothelium (CA125) and other cells (PHL) by the infection. HA may reflect stromal changes. Subsequently, peritoneal healing (PICP,PIIINP) and remesothelialization (second peak CA125) are likely to occur.

CONCLUSIONS

Dialysate concentrations of these substances can be used as markers for the effects of peritonitis on the peritoneum of CAPD patients in vivo. The similarity between the marker concentrations in the effluent after recovery from peritonitis and those in stable CAPD patients implies that complete peritoneal healing is likely to occur after uncomplicated peritonitis.