Intraperitoneal verapamil therapy in CAPD patients with peritoneal hypopermeability. Effects on ultrafiltration

We found higher peritoneal lymphocyte (PLy) and macrophage (PM0) Ca++ concentrations in CAPD patients with low peritoneal ultrafiltration (UF), than in normal UF patients, as well as the release of greater amounts of lymphomonokines such as interferon-gamma and interleukin-1, which stimulate peritoneal fibroblast proliferation. Since Ca++ is essential in immune-cell activation and lymphomonokine production, the authors analyzed the effects of intraperitoneal (IP) verapamil therapy in 16 CAPD patients with UF loss. The areas studied included: 1) PLy and PM0 Ca++ concentration, 2) peritoneal dialysis effluent (PDE) lymphomonokine levels, 3) peritoneal glucose absorption, 4) UF volume, and 5) peritoneal morphology. In the 10 low UF patients who showed normal glucose absorption and increased peritoneal fibroblast proliferation, of verapamil therapy increased UF volume, decreased the amount of peritoneal fibroblast proliferation, and normalized the previously high PLy and PM0 Ca++ concentrations and PDE lymphomonokine levels. Conversely, UF was not improved by IP verapamil in the six low UF patients showing high glucose absorption and prevalent mesothelial alterations. In conclusion, IP verapamil can be considered a suitable therapy for increasing UF volume in CAPD patients with peritoneal hypopermeability due to a lymphomonokine-mediated hyperproliferation of peritoneal fibroblasts.