Study of epidermal “downgrowth” at catheter exit site

A probe (2mm in diameter) was inserted through the CAPD catheter exit site, and the longest distance covered by the catheter was defined as “downgrowth” (“DGR”). Then the downgrowth (DGR) was actually measured in 4 cases in surgery. In 3 cases free from infections, DGR (7, 10, 10mm) almost agreed to “DGR” (7, 12, 8mm). In 47 cases (at 27.3±14.0 months after initiation of CAPD), “DGR” was 10.5±4.7mm. “DGR” was not correlated with sinus tract (ST) and the duration of CAPD. When these cases were divided by the length of ST into under-30mm (23.1±5.4mm, n=22) and over-31mm groups (57.0±23.7mm, n=25), “DGR” was significantly shorter in the former groups. There was no correlation between “DGR” and the site of exit. “DGR” was markedly lengthened when exit infection was present, which suggested that the tissue around the catheter became fragile by infection. The DGR of the CAPD catheter was clarified by the measurement of “DGR”.