Less frequent catheter dressing changes decrease local cutaneous toxicity of high-dose chemotherapy in children, without increasing the rate of catheter-related infections: results of a randomised trial.

Cutaneous lesions caused by catheter dressing changes can be serious and generate local pain in children undergoing high-dose chemotherapy followed by bone marrow transplantation. One hundred and thirteen children entered a randomised trial to compare two catheter dressing change frequencies (15 days vs 4 days). Skin toxicity was classified according to the following scale: grade 0: healthy skin, to grade 4: severe skin toxicity. A qualitative culture of the skin at the catheter entry site was taken whenever the dressing was changed. Of the 112 evaluable children (56 in each group) 32 developed grade > or = 2 local skin toxicity (eight in the 15-day group and 24 in the 4-day group; P = 0.001). Although higher in the 4-day group, the proportions of children experiencing pain during and between dressing changes were not statistically different between the two groups. The proportion of patients with one or more positive skin culture(s) at the catheter entry site during hospitalisation were similar in the two groups (27% in the 15-day group and 23% in the 4-day group) as were the proportions of documented nosocomial bloodstream infections (11% and 13%; NS). Whereas the planned frequency was maintained in the 4-day group (mean = 4 days, s.d. = 1), it was usually shortened in the 15-day group (mean = 8 days, s.d. = 4), mainly because dressings had loosened. Decreasing the catheter dressing change frequency proved efficient in reducing cutaneous toxicity without increasing the risk of local and systemic infection. In our unit, catheter dressings are changed every 8 days since this analysis.

In vitro generation of cytotoxic effectors activated by interleukin 2 (IL-2): comparison of autologous peripheral blood stem cells (PBSC) from adults and children.

Previous studies demonstrated that ex vivo IL-2- activated PBSC could generate cytotoxic effectors without impairing haematopoietic reconstitution. Clinical experience and previous studies indicated that children with solid tumours could benefit from high-dose chemotherapy with immune modulation. We studied the generation of cytotoxic effectors from growth-factor +/- chemotherapy-mobilised PBSC from 10 patients (five adults and five children) with different solid tumours. Cells were placed in culture in serum-free culture medium supplemented with IL-2 1000 U/ml +/- IL-12 for 1, 2, 4 or 7 days. Anti-tumour cytotoxicity was tested against K562, Daudi and two neuroblastoma cell lines (Gau, NB91). Cultured adult PBSC in the presence of IL-2 (1000 U/ml) showed marked cytotoxicity against all the cell lines tested from day 1. At day 2, with an E:T ratio of 25:1, cytotoxicity was 53% +/- 10.4, 63.2% +/- 23.8, 38% +/- 9.1, and 39% +/- 15.7 against K562, Daudi, Gau and NB91, respectively. Cytotoxic activity of child PBSC was significantly lower (P < 0.05) and was displayed after longer culture times (day 4). No difference was found in the phenotype analysis of lymphoid subsets before and after IL-2 activation between adult and child PBSC. Haematological properties of the graft were not significantly impaired by IL-2 activation.