The effect of dwell time on peritoneal phagocytic defense of chronic peritoneal dialysis patients.

: We studied the phagocytic capacity of peritoneal macrophages (PM) isolated from effluents after 4 different dwell times (1.5 to 15 hours) in six stable CAPD patients. In addition IgG and C3 levels as well as opsonic activity of the effluents were measured. Both IgG levels and opsonic activity increased significantly with prolonged dwell times. The same held true for the number of phagocytes and their phagocytic capacity. Thus prolonged dwell time enhanced both opsonic activity and phagocytic capacity significantly. As in CCPD the dwell time period between (dis)connection procedures is much longer than in CAPD, this might play an important role in the lower peritonitis rate among CCPD-treated patients.