Two-operator glucose infusion test (GIT2) for vascular access recirculation measurement during hemodialysis.

Vascular access recirculation rate (AR) monitoring is fundamental to guarantee treatment adequacy and to detect access failure early. We have evaluated the GIT2 test to measure AR unaffected by cardio-pulmonary recirculation (CPR), based on a short glucose infusion in place of the bolus and on a two-operator sampling, differently from the classical glucose infusion test (GIT). The GIT2 test is based on four steps: 1) basal (B) glucose arterial sample; 2) 10% glucose infusion for 1 min, by infusion pump at 600 ml/hr; (or 20% at 300 ml/hr); 3) simultaneous sampling at arterial (A) and venous (V) ports, after 35-40 sec from starting the infusion, taking care to avoid blood pump stop during the test; 4) AR=100*((A-B)/(V-B)). In vitro tests by dialysis on a 40 L tank containing a urea solution, with AR volumetrically simulated at 0, 5, 10, 20%, and in vivo comparison of GIT, GIT2 with stop-flow (SF) urea method. Our results have shown in vitro an almost perfect correspondence of SF urea method and a better reliability of GIT2 than GIT. The methylene-blue test has shown that a single color bolus in V reaches the A port after variable time, depending on blood flow and AR, while the continuous infusion determines a steady gradient after about 30". In vivo tests (n=24) show good correspondence between GIT2 (4.37 +/- 3.36) and SF (4.51 +/- 3.62), while GIT data (1.01 +/- 0.51) are significantly underestimated. In conclusion, our preliminary results have evidenced a good reliability of the new test, the continuous infusion causing a steady gradient in V and A that more precisely reflects the AR rate.

Malignancy after kidney transplantation: results of 400 patients from a single center.

BACKGROUND: Post-transplant malignancies (PTM) occur in a percentage as high as 50% in patients followed 20 yr and have become a main cause of mortality and are expected to be the first cause of death within the next 20 yr in kidney transplant recipients. PATIENTS AND METHODS: We analyzed the PTM incidence in our kidney transplant recipients, and its main risk factors. The records of 400 patients (min follow up = one yr) have been retrospectively reviewed and categorized into three groups: patients without any tumor, with a non-melanoma skin cancer and with a solid or hematologic cancer. A cancer-free multivariate survival study was performed stratified by age, sex, immunosuppressive therapy, time on dialysis, body mass index (BMI), smoke, diabetes and nephropathy. RESULTS: Thirty patients developed PTM: 12 non-melanoma skin cancer, three lymphomas and 15 solid malignancies (seven genitourinary, three lung, two breast, two gastrointestinal and one sarcoma). The mean age at diagnosis was 55 yr, with a mean time from transplant of 27 months. We observed six deaths and two graft losses. Non-melanoma skin cancer-free survival and the solid/hematologic cancer-free survival was 99.5% and 98.5% at one yr, and 95.2% and 94.6% at five yr, respectively. At univariate analysis, age and induction therapy were significant risk factors for both types of PTM, while only recipient age significantly increased the risk of all PTM, and anti CD25 significantly reduced the risk of non-melanoma skin cancer at the multivariate study. CONCLUSIONS: These data confirm the role of age and induction strategies in modulating the risk of neoplasia. To look for which strategies might reduce the PTM risk, including a personalized therapy to minimize the effects of chronic immunosuppressant, will be a crucial goal.