Finding Eden - alternative transplantation sites for pancreatic islets

Pancreatic islets transplantation is an established treatment method for type 1 diabetic patients with the hypoglycemia unawareness syndrome in whom a therapy with modern technologies fails. Islet transplantation is most commonly done using an interventional radiology method: a tissue suspension of pancreatic islets is applied into a branch of the portal vein through a percutaneously installed catheter. Although being minimally invasive unlike pancreas organ transplant, this method is associated with many technical difficulties. Possible complications of the procedure include hemorrhage and portal vein thrombosis. Unlike their natural dispersed localization in exocrine pancreas, isolated pancreatic islets are exposed to hypoxia, toxins and immunosuppressive drugs in the liver parenchyma. Direct contact with the recipients blood causes an instant blood mediated inflammatory reaction (IBMIR) resulting in the death of more than half of the pancreatic islets shortly after their application. Therefore the size of the islet graft is often insufficient and a number of transplanted patients require administration of exogenous insulin. All of these are reasons for seeking an alternative transplantation site with more hospitable conditions for long-term islet survival. Various transplantation sites have been tested in experimental and clinical research. The advantages and disadvantages of some of them are summarized in this paper. Currently, transplantation into the greater omentum seems most promising, which has already been used in clinical practice at several institutions.

Predictive Potential of Flow Cytometry Crossmatching in Deceased Donor Kidney Transplant Recipients Subjected to Peritransplant Desensitization

Recipient sensitization is a major risk factor of antibody-mediated rejection (ABMR) and inferior graft survival. The predictive effect of solid-phase human leukocyte antigen antibody testing and flow cytometry crossmatch (FCXM) in the era of peritransplant desensitization remains poorly understood. This observational retrospective single-center study with 108 donor-specific antibody (DSA)-positive deceased donor kidney allograft recipients who had undergone peritransplant desensitization aimed to analyze variables affecting graft outcome. ABMR rates were highest among patients with positive pretransplant FCXM vs. FCXM-negative (76 vs. 18.7%, p < 0.001) and with donor-specific antibody mean fluorescence intensity (DSA MFI) > 5,000 vs. <5,000 (54.5 vs. 28%, p = 0.01) despite desensitization. In univariable Cox regression, FCXM positivity, retransplantation, recipient gender, immunodominant DSA MFI, DSA number, and peak panel reactive antibodies were found to be associated with ABMR occurrence. In multivariable Cox regression adjusted for desensitization treatment (AUC = 0.810), only FCXM positivity (HR = 4.6, p = 0.001) and DSA number (HR = 1.47, p = 0.039) remained significant. In conclusion, our data suggest that pretransplant FCXM and DSA number, but not DSA MFI, are independent predictors of ABMR in patients who received peritransplant desensitization.

Transabdominal two-cavity approach for radical nephrectomy combined with inferior vena cava thrombectomy for malignant thrombus caused by renal cell carcinoma: a case series

BACKGROUND

Advanced renal cell carcinoma in some cases causes malignant intravascular thrombus with the potential for growth into the inferior vena cava or even the right atrium. Renal cell carcinoma is accompanied by malignant intravascular thrombus in up to 10% of cases. We present an overview of three patients diagnosed as having renal cell carcinoma with malignant intravascular thrombus requiring radical nephrectomy combined with inferior vena cava thrombectomy.

CASE PRESENTATION

Three patients diagnosed as having renal cell carcinoma were indicated for renal cell carcinoma combined with inferior vena cava thrombectomy between 2014 and 2017 at our department: a 69-year-old white Caucasian woman, a 74-year-old white Caucasian woman, and a 58-year-old white Caucasian woman. According to the Novick classification of inferior vena cava tumor thrombus, there was one infrahepatic (level II) and two supradiaphragmatic (level IV) malignant intravascular thrombi. The average age of these patients was 67 years (range 58-74 years). All patients underwent radical nephrectomy combined with inferior vena cava thrombectomy through transabdominal approach. In patients with level IV malignant intravascular thrombus, transesophageal echocardiogram was used to guide the placement of the inferior vena cava cross-clamp above the diaphragm. In one patient the pericardium was opened to place a cross-clamp above a tumor just below the right atrium. There were no postoperative mortalities to date with an average follow-up of 23 months (range 2-48 months). To date, no patient has demonstrated recurrent inferior vena cava malignant intravascular thrombus requiring secondary inferior vena cava thrombectomy or any other treatment. A comparison of estimated blood loss and transfusion rate was not significantly different in all three cases.

CONCLUSION

Despite the technical complexity of the procedure, caval thrombectomy combined with radical nephrectomy currently represents the only radical treatment for renal cell carcinoma accompanied by malignant intravascular thrombus with good mid-term oncological outcomes.

Simultaneous living donor orthotopic renal transplantation and bilateral nephrectomy for recurrent renal cell carcinoma and renal failure: case report and review of literature

Background

We report the case of a 43-year-old female patient with systemic lupus erythematosus, class III lupus nephritis, with predialysis creatinine levels around 350 μmol/L (3.95 mg/dL) after partial resection of the left kidney with histologically verified papillary carcinoma in 2010. Preoperative computed tomography of the abdomen revealed a small 8 mm tumor in the left upper kidney pole. The patient was indicated for simultaneous bilateral nephrectomy and orthotopic renal transplantation with the aim to minimize invasiveness of the procedure as well as for curable tumor removal.

Method

The procedure was performed under the full anesthesia trough upper middle laparotomy. As the first step, bilateral transperitoneal nephrectomy was performed. The live donor surgery started in a parallel theater to shorten the cold ischemic time of the graft. The renal graft had singe vessels and ureter; it was placed into the recipient’s right orthotopic position. End-to-end anastomosis of the right renal vein and artery anastomosis were performed; ureter was anastomosed end-to-end using recipient’s ureter.

Results

The postoperative period was uneventful with repeatedly excellent ultrasonography check-up of the graft’s perfusion. The patient was discharged after 13 days with a good renal function of the graft (urea: 15 mmol/L, creatinine 160 μmol/L [1.80 mg/dL]).

Conclusion

Orthotopic renal transplantation is a technically challenging but valid alternative for patients who are unsuitable candidates for heterotopic renal transplantation or in cases where there is a clear benefit of orthotopic renal transplantation.

The Effects of Diuresis, Duration of Dialysis and Age on Lower Urinary Tract Function in Urologically Healthy Male Patients on the Waiting List for Kidney Transplant

PURPOSE

This work investigated the effects of diuresis, duration of dialysis and age on lower urinary tract function in urologically healthy males on the waiting list for kidney transplant.

MATERIALS AND METHODS

The study included all men who had kidney transplants at our centre between January 2009 and December 2014 who had normal urological findings prior to inclusion on the list. Diuresis, the duration of haemodialysis, age, and parameters of function of the lower urinary tract as determined by filling and voiding cystometry were evaluated.

RESULTS

The study included 127 men (median age, 59 years; median diuresis, 250 mL; median duration of dialysis, 469.5 days). We found that greater diuresis was accompanied by significantly higher FDV, FDV/Cmax, NDV,Cmax and compliance and by significantly lower Pdet.max, PdetQmax and BOOI. Longer duration of dialysis was accompanied by significantly lower FDV, NDV and Cmax, compliance and Qmax.p and with significantlyhigher Pdet.max, PdetQmax and BOOI. Older age was associated with significantly higher Pdet.max and with significantly lower compliance. Worsening of the basic parameters of the storage function of the lower urinary tract occurred when diuresis decreased to 500-750 mL, when the duration of dialysis was one year and when patients were older than 54 years.

CONCLUSION

In healthy male patients on the waiting list for kidney transplant, there were connections between the occurrence of dysfunctions of the lower urinary tract and diuresis, duration of dialysis and age. Patients should be monitored for dysfunctions of the lower urinary tract before and after transplantation.

Aorto-iliac endarterectomy: Old-fashioned or re-newed method?

INTRODUCTION

Aorto-iliac occlusive disease is best treated with endovascular angioplasty/stenting or surgical bypass, depending on disease severity. Aorto-iliac endarterectomy was frequently used until the 1980s. However, it can still be performed in cases of previous failure or contraindication of standard methods. The aim was a retrospective evaluation of a single-center case series of aorto-iliac endarterectomy.

METHODS

Seven patients at mean age 60±8 years (5768 years) were treated by aorto-iliac endarterectomy between 2013 and 2018. Rutherford categories of leg ischemia were 2 (moderate claudication) 3x, 3 (severe claudication) 2x, 4 (rest pain) and 5 (toe gangrene). The reasons for endarterectomy approach were: late in-stent iliac occlusion in an oncology patient, failure or complication of previous endovascular treatment of short iliac stenosis 2×, high infection risk of prosthesis use in long iliac-femoral occlusion, and short iliac occlusions 3x. Two patients after previous organ transplant were on immunosuppression.

RESULTS

Technical success rate was 100%. There was no peri-operative (30 days) death or amputation. Mean follow-up was 17 months (1.1 month3.3 year). One patient required additional tibial bypass 1 month after endarterectomy to heal foot gangrene. One patient developed symptomatic re-stenosis which was treated with iliac stenting 8 months after procedure. All patients clinically improved and recovered from leg ischemia. Two patients died of tumor with preserved limb 1.1 month and 3.1 years after procedure, respectively. Five remaining patients are asymptomatic with patent revascularization to date.

CONCLUSION

Aorto-iliac endarterectomy is a vital alternative technique for revascularization in selected patients when other methods seem inappropriate. Key words: endarterectomy - peripheral arterial disease - iliac artery - abdominal aorta.

[Simultaneous transplantation of the kidney and the islets of Langerhans]

Simultaneous kidney and islet transplantation is recent therapeutic alternative for diabetics with end-stage kidney disease, who are not acceptable for simultaneous pancreas-kidney transplantation. Islet transplantation has less complications but still worse long-term function compared to whole pancreas transplantation.

[Clinical experience with cold-preservation of venous and arterial allografts. long-term outcomes]

INTRODUCTION

Venous and arterial allografts extend the possibilities of peripheral arterial disease as well as vascular prosthesis infections treatment.

MATERIAL AND METHODS

Between 10/1997 and 1/2009 we used 112 allogeneic vessels (30 arteries, 82 veins) in 104 patients. Venous allografts were used for 82 reconstructions in 75 patients (M/F 41/34, aged 41-85 years, median 66 years) with critical limb ischemia and no suitable autogenous venous material. Arterial allografts were used in 9 patients (M/F 8/1, aged 56-77 years, median 63 years) with aortoiliac prosthetic infections or mycotic abdominal aortic aneurysms and in 20 transplanted patients (M/F 11/9, aged 32-67 years, median 56 years) with aortoiliac atherosclerotic disease.

RESULTS

Patients survival rate after allovenous bypasses was 92% at 1 year and 78% at 3 years. Limb salvage rate was 67% at 1 year and 53% and 3 years. Secondary patency rate was 48% at 1 year and 27% at 3 years. Patient survival rate after alloarterial bypasses was 86% at 1 year and 69% at 3 years. No signs of arterial grafts aneurysmal formation and no need for secondary intervention of any arterial reconstruction was observed during the follow up period in any patient after alloarterial transplantation.

CONCLUSIONS

Cold-stored venous and arterial allografts are suitable alternative conduits for limb salvage procedures, vascular prosthesis infections as well as for arterial reconstructions in transplanted patients.

Cold-stored Venous Allografts in the Treatment of Critical Limb Ischaemia

OBJECTIVES

To assess the outcome of cold-stored venous allografts in critically ischemic limbs in patients with no ipsilateral autogenous greater saphenous vein.

DESIGN

A non-randomised, retrospective, single-center study.

METHODS

From September 2000 to June 2006, 46 cold-stored venous allografts obtained during multiorgan harvest were implanted into 44 critically ischaemic limbs of 43 patients. The indication for reconstructions was rest pain (24%) or tissue lost (76%). Sixty-seven percent of procedures were performed as secondary reconstructions, and 61% of veins were anastomosed to tibial or pedal arteries. Thirty-seven percent of patients received prednisone, and 46% tacrolimus as postoperative immunosuppressive therapy. Mean patient follow-up period was 13.3 months (range 1 week to 60 months).

RESULTS

The secondary patency rate for the cohort was 83+/-5.6% at 1 month, 64+/-8.2% at 6 months, 57+/-10.0% at 12 months and 46+/-10.7% at 24 months. Limb salvage rate was 96+/-3.1% at 1 month, 78+/-6.9% at 6 months, 71+/-8.1% at 12 months and 50+/-11.8% at 24 months.

CONCLUSION

Cold-stored venous allografts are an alternative conduit for limb salvage procedures when ipsilateral autogenous vein is unavailable.