Increased levels of transforming growth factor beta 1 and basic fibroblastgrowth factor in patients on CAPD: A study during non-infected steady state and peritonitis

Long-term influence of continuous ambulatory peritoneal dialysis (CAPD) on concentrations of transforming growth factor beta 1 (TGF-beta 1) and basic fibroblast growth factor (bFGF) in the peritoneal effluent, and the effect of peritonitis on these cytokines were investigated. TGF-beta 1 and bFGF we re assayed in effluent samples from dialysate bags collected during the ini tial week of treatment with CAPD and at 5 months. To determine the effect o f peritonitis, dialysate bags were collected on admission to the hospital a nd on days 3 and 10 and also during non-infected steady state. Serum was dr awn prior to infection and on days 1 and 10. TGF-beta 1 increased more than threefold during the longitudinal follow-up period, median concentrations of 35 pg/ml to 106 pg/ml (P < 0.05). No change in bFGF was seen during this initial 5 months. TGF-beta 1 was increased on the first day of peritonitis (median concentration 169 pg/ml) and reached its maximum on day 3 of infec tion, (median concentration 216 pg/ml) (P < 0.05 vs non-infected state, med ian concentration 39 pg/ml). Basic FGF reached a maximum on day three of in fection (median concentration 7.7 pg/ml; P = 0.01 vs non-infected state) an d then slowly declined. In conclusion, TGF-beta 1 is influenced by CAPD tre atment per se, and together with bFGF is increased during peritonitis, indi cating its importance in the peritoneum and its potential involvement in th e development of tissue fibrosis and eventually ultrafiltration failure.