Navigated laparoscopic microwave ablation of tumour mimics in pig livers: a randomized ex-vivo experimental trial.

BACKGROUND: In order to efficiently perform laparoscopic microwave ablation of liver tumours precise positioning of the ablation probe is mandatory. This study evaluates the precision and ablation accuracy using the innovative laparoscopic stereotactic navigation system CAS-One-SPOT in comparison to 2d ultrasound guided laparoscopic ablation procedures. METHODS: In a pig liver ablation model four surgeons, experienced (n = 2) and inexperienced (n = 2) in laparoscopic ablation procedures, were randomized for 2d ultrasound guided laparoscopic or stereotactic navigated laparoscopic ablation procedures. Each surgeon performed a total of 20 ablations. Total attempts of needle placements, time from tumor localization till beginning of ablation and ablation accuracy were analyzed. RESULTS: The use of the laparoscopic stereotactic navigation system led to a significant reduction in total attempts of needle placement. The experienced group of surgeons reduced the mean number of attempts from 2.75 ± 2.291 in the 2d ultrasound guided ablation group to 1.45 ± 1.191 (p = 0.0302) attempts in the stereotactic navigation group. Comparable results could be observed in the inexperienced group with a reduction of 2.5 ± 1.50 to 1.15 ± 0.489 (p = 0.0005). This was accompanied by a significant time saving from 101.3 ± 112.1 s to 48.75 ± 27.76 s (p = 0.0491) in the experienced and 165.5 ± 98.9 s to 66.75 ± 21.96 s (p < 0.0001) in the inexperienced surgeon group. The accuracy of the ablation process was hereby not impaired as postinterventional sectioning of the ablation zone revealed. CONCLUSION: The use of a stereotactic navigation system for laparoscopic microwave ablation procedures of liver tumors significantly reduces the attempts and time of predicted correct needle placement for novices and experienced surgeons without impairing the accuracy of the ablation procedure.

Prospective Analyses of Circulating B Cell Subsets in ABO-Compatible and ABO-Incompatible Kidney Transplant Recipients.

Immunosuppressive strategies applied in renal transplantation traditionally focus on T cell inhibition. B cells were mainly examined in the context of antibody-mediated rejection, whereas the impact of antibody-independent B cell functions has only recently entered the field of transplantation. Similar to T cells, distinct B cell subsets can enhance or inhibit immune responses. In this study, we prospectively analyzed the evolution of B cell subsets in the peripheral blood of AB0-compatible (n = 27) and AB0-incompatible (n = 10) renal transplant recipients. Activated B cells were transiently decreased and plasmablasts were permanently decreased in patients without signs of rejection throughout the first year. In patients with histologically confirmed renal allograft rejection, activated B cells and plasmablasts were significantly elevated on day 365. Rituximab treatment in AB0-incompatible patients resulted in long-lasting B cell depletion and in a naïve phenotype of repopulating B cells 1 year following transplantation. Acute allograft rejection was correlated with an increase of activated B cells and plasmablasts and with a significant reduction of regulatory B cell subsets. Our study demonstrates the remarkable effects of standard immunosuppression on circulating B cell subsets. Furthermore, the B cell compartment was significantly altered in rejecting patients. A specific targeting of deleterious B cell subsets could be of clinical benefit in renal transplantation.

Onset and progression of de novo donor-specific anti-human leukocyte antigen antibodies after BK polyomavirus and preemptive immunosuppression reduction.

BACKGROUND: BK polyomavirus (BKPyV) viremia/nephropathy and reduction in immunosuppression following viremia may increase the risk of alloimmune activation and allograft rejection. This study investigates the impact of BKPyV viremia on de novo donor anti-human leukocyte antigen (HLA)-specific antibodies (dnDSA). PATIENTS AND METHODS: All primary renal transplants at East Carolina University from March 1999 to December 2010, with at least 1 post-transplant BKPyV viral load testing, were analyzed. Patients were negative for anti-HLA antibodies to donor antigens (tested via single antigen beads) at transplantation and at first BKPyV testing. RESULTS: Nineteen of 174 patients (11%) tested positive for BKPyV viremia. Within 24 months of BKPyV viremia detection, 79% of BKPyV-viremic patients developed dnDSA. Only 20% of BKPyV viremia-persistent cases, compared to 86% of BKPyV viremia-resolved cases, developed dnDSA (P = 0.03). Poor allograft survival was evident in BKPyV viremia-persistent patients (60% failure by 2 years post BKPyV diagnosis) and in BKPyV viremia-resolved patients with dnDSA (5-year post BKPyV diagnosis allograft survival of 48%). CONCLUSIONS: Post-transplant BKPyV viremia and preemptive immunosuppression reduction is associated with high rates of dnDSA. When preemptively treating BKPyV viremia, dnDSA should be monitored to prevent allograft consequences.

Correlation Between the Transplant Evaluation Rating Scale (TERS) and Medical Outcomes in Living-Donor Kidney Transplant Recipients: A Retrospective Analysis.

BACKGROUND: Pretransplant psychosocial evaluation of living-donor kidney transplantation (LDKT) candidates identifies recipients with potentially inferior posttransplant outcomes. Rating instruments, based on semi-standardized interviews, help to improve and standardize psychosocial evaluation. The goal of this study was to retrospectively investigate the correlation between the Transplant Evaluation Rating Scale (TERS) and transplant outcome in LDKT recipients. METHODS: TERS scores were retrospectively generated by 2 raters based on comprehensive interviews of 146 LDKT recipients conducted by mental health professionals (interrater reliability, 0.8-0.9). All patients were eligible for transplantation according to pretransplant psychosocial evaluation. Patients were classified into 2 groups according to their TERS scores, in either two thirds excellent risk (TERS <29) and one third at least moderate risk (TERS ≥29) candidates. Analyzed medical parameters were change in estimated glomerular filtration rate and acute rejection (AR) episodes within the first year posttransplant. In addition, a subgroup of 65 patients was tested for de novo donor-specific HLA antibodies (DSA) posttransplant. RESULTS: There was no significant difference between the excellent (n = 97) and at least moderate (n = 49) risk candidates according to TERS in terms of organ function (estimated glomerular filtration rate decline >25%: 17 of 97 vs 11 of 49; P = .51) and episodes of AR (19 of 97 vs 15 of 49; P = .15). Patients developing de novo DSA (n = 18 [28%]) did not have higher pretransplant TERS scores (DSA positive, 11 of 42 vs 7 of 23; P = .78). CONCLUSIONS: Classifying LDKT recipients according to TERS score did not predict medical outcome at 1 year posttransplant or the occurrence of de novo DSA.

Postoperative Continuous Infusion of Local Anesthesia in Hand-Assisted Retroperitoneoscopic Living Donor Nephrectomy.

INTRODUCTION: Postoperative pain management in living kidney donor nephrectomy plays a key role in donor comfort and is important for the further acceptance of living kidney donation in times of organ shortage. Standard pain treatment (SPT) based on opioids is limited due to related side effects. Continuous infusion of local anesthesia (CILA) into the operative field is a promising alternative. The aim of this study was to evaluate whether CILA could reduce the dose of opioids in living kidney donors operated with hand-assisted retroperitoneoscopic donor nephrectomy (HARP). METHODS: An observational study on 30 living donors was performed. The primary outcome was the difference of morphine equivalents (MEQ) administered between CILA and SPT. RESULTS: On day 0 and 1, living donors with CILA received significant less MEQ compared to the SPT group, although on day 1 this effect was not statistically significant (day 0: 6.3 mg, interquartile range [IR] 4.2-11.2 vs 16.8 mg, IR 10.5-22.1, P = .009; day 1: 5.25 mg, IR 2.1-13.3 vs 13.3 mg, IR 6.7-23.8, P = .150). On days 2 and 3 there was no difference (day 2: 13.3 mg, IR 0.0-20.0 vs 13.3 mg, IR 6.7-13.3, P = .708; day 3: 13.3 mg, IR 0.0-26.7 vs 13.3 mg, IR 6.7-20, P = .825). Overall (days 0 to3) MEQ was also less for CILA without reaching statistical significance (39.6 mg, IR 10.9-70.5 vs 59.6 mg, IR 42.4-72.9, P = .187). CONCLUSIONS: CILA seems to be an effective instrument for donor pain management in the first 24 hours after HARP. Its effect abates by 48 hours after surgery, especially if highly potent nonopioids are given.