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Abstract: Background: The use of kidneys from elderly deceased donors has substantially increased organ supply, although it is associated with worse graft function and survival rates. The risk of kidneys from elderly donors as well as expanded criteria donors (ECDs) on kidney transplant outcome was investigated. Patients and methods: Seventy-five kidney transplants from ECDs over a 5-year period were reviewed retrospectively. Old age and increased donor risk variables were analyzed separately in relation to graft function and survival. Results: Sixty-four of 75 (85.3%) recipients had functioning grafts 5 years posttransplant. The overall actuarial graft survivals from 1 to 5 years were 87.5%, 68.1%, 57.3%, 55.4%, and 47.3%, respectively. Early graft function gave 47 (62.7%) kidneys remarkable actuarial survivals of 100.0%, 88.3%, 75.8%, 75.8%, and 68.4% at 1 to 5 years posttransplant, and 28 (37.3%) kidneys had delayed graft function with substantially decreased actuarial survival rates, ranging from 66.7% to 23.2%. Kidneys from elderly donors had considerable actuarial graft survival rates of 100.0%, 83.3%, 76.9%, 76.9%, and 67.0% from 1 to 5 years, respectively; these were the best graft survival rates compared with kidneys from the other donor categories. The other donor risk variables when associated with advanced age of any had an adverse effect on recipient graft function and survival, but no single risk variable alone, or a combination of any two, showed any statistically significant variability. Conclusion: Elderly kidney donors provided a substantial organ pool expansion without affecting patient and graft survival in many patients. ECDs can be utilized safely if adequate measures are taken. [Copyright &y& Elsevier]

Abstract: The Hellenic Transplant Organization (HTO), a nonprofit organization sector of the Greek Ministry of Health, was officially established in 1999. Since March 2001, HTO has been responsible for donation and transplantation processes in Greece and organ sharing between Greece and other European countries. The organization’s main tasks are: donor referral, charting, donor assessment, organ evaluation, organ allocation and transplantation. Today, the results show increased success rates to previously believed unthinkable levels. Precisely, the percentage of referred versus used cadaveric donors increased by 468% and 134%, respectively. Cadaveric kidney transplantation has also shown remarkable progress with a 126% increase during the same period. Similarly, liver transplantation showed a threefold rise (89%) during the same time. Unfortunately, heart and lung transplantations remain low, thus preventing statistical conclusions to be drawn. Although Greece in previous years had the lowest donor and transplantation rates per million population, its position compared with other European countries is expected to rise significantly this year. Undoubtedly, the numbers and percentages compared to previous years are due to the radical changes implemented by the HTO, by introducing transplant coordination principles and procurement management, which were concepts not previously established in Greece. However, there are still major obstacles, such as intensivists’ refusal to disconnect, inaccessible geographical locations, few transplant centers, and society’s suspicion of organ donation concept, that still need attention. Nevertheless, the first step has been taken and other European countries standards will hopefully be attained soon. [Copyright &y& Elsevier]

Abstract: The success of a transplantation program depends upon the quality and effectiveness of the donation process, whereby the key role is assigned to the local transplant coordinator (TxC). This important professional figure was only recently established in Greece. The local TxC duties were outlined alongside those of the Hellenic Transplant Organization (HTO) foundation in 1999, whereby three different transplant coordinator positions—central, local, and clinical—were specified. In 2002, the above-mentioned positions were legally consolidated. Local TxCs had to be doctors or nurses, in a 70%-30% ratio, already working in intensive care unit (ICU) and had to be appointed by the hospital and ICU directors in each hospital as requested by the HTO. By the end of 2004, this network consisted of 122 TxCs located in 74 ICUs, especially trained in donation procedures and ethics. Half of the doctors were ICU directors, especially appointed to influence ICU personel. Furthermore in 2005, the board of directors of HTO decided that there should be closer cooperation between the 45 most donor generating ICUs and their TxCs. It was decided that the local TxCs would work part-time and receive a monthly grant. The 45 ICU network started in 2005, resulting in an 154% increased rate of potential donor referrals and a 33% and almost 38% increase in actual donors and transplantations, respectively, compared to 2004. This substantial increase was achieved by the institution of TxC network. [Copyright &y& Elsevier]

Background: Replacement of β-cells with the use of isolated islet allotransplantation (IT) is an emerging therapy for type 1 diabetics with hypoglycemia unawareness. The current standard protocol calls for a 36-72-hour culture period before IT. We examined 13 clinical islet preparations with ≥2 purity fractions to determine the effect of culture on viability. Methods: After standard islet isolation and purification, pure islet fractions were placed at 37°C with 5% CO2 for 12-24 hours and subsequently moved to 22°C, whereas less pure fractions were cultured at 22°C for the entire duration. Culture density was targeted at a range of 100-200 islet equivalents (IEQ)/cm² adjusted for purity. Islets were assessed for purity (dithizone staining), quantity (pellet volume and DNA), and viability (oxygen consumption rate normalized to DNA content [OCR/DNA] and membrane integrity). Results: Results indicated that purity was overestimated, especially in less pure fractions. This was evidenced by significantly larger observed pellet sizes than expected and tissue amount as quantified with the use of a dsDNA assay when available. Less pure fractions showed significantly lower OCR/DNA and membrane integrity compared with pure. The difference in viability between the 2 purity fractions may be due to a variety of reasons, including hypoxia, nutrient deficiency, toxic metabolite accumulation, and/or proteolytic enzymes released by acinar tissue impurities that are not neutralized by human serum albumin in the culture media. Conclusions: Current clinical islet culture protocols should be examined further, especially for less pure fractions, to ensure the maintenance of viability before transplantation. Even though relatively small, the difference in viability is important because the amount of dead or dying tissue introduced into recipients may be dramatically increased, especially with less pure preparations. [ABSTRACT FROM AUTHOR]

Background Serum creatinine (S-Cr) is the most commonly used marker for the assessment of renal function in kidney transplantation (KTx). Cystatin-C (Cys-C) has been proposed as an alternative marker of renal function for the estimated glomerular filtration rate (eGFR), which seems to be more accurate than S-Cr. The aim of this study was to investigate the relationship between changes in S-Cr, Cys-C, and eGFR measurements in KT patients during the early post-transplantation (post-Tx) period. Methods Fifty consecutive patients, aged 15 to 70 years, were subjected to KT. Blood samples were collected at stable time-points on pre-Tx and post-Tx days 2, 6, and 14 and in the third month. Cys-C and S-Cr levels were measured, and GFR was estimated at all time-points using the Cockcroft–Gault and Le Bricon equations. Results S-Cr and Cys-C levels decreased significantly post-Tx in all time-point determinations compared with pre-Tx levels. Both markers showed a parallel decrease, reaching normal levels in the third month. Estimated GFR post-Tx by S-Cr and Cys-C exhibited a parallel progressive increase without significant difference between the calculations. Correlation between S-Cr and Cys-C in all time-point determinations was positive and of high significance using Pearson's correlation ( r = 0.969, P < .01; r = 0.951, P < .01; r = 0.969, P < .01; r = 0.701, P < .01). Also, the correlation between the eGFR by Cys-C and S-Cr was positive and of high significance in all post-Tx calculations ( r = 0.896, P < .01; r = 0.935, P < .01; r = 0.929, P < .01; r = 0.861, P < .01). Ten recipients had acute rejection and were treated successfully with antirejection therapy. Their S-Cr, cys-C, and eGFR results were analyzed separately and showed a significant difference from no-rejection patients, with Cys-C being more sensitive to earlier eGFR changes. Conclusion Cystatin-C is an alternative and accurate marker of renal function in KT patients showing similar diagnostic characteristics to S-Cr. However, Cys-C appears superior to S-Cr in reflecting early GFR temporary changes, which is critical for the early detection of acute rejection. [ABSTRACT FROM AUTHOR]

Abstract: Urological complications after renal transplantation increase morbidity, delay graft function, and occasionally lead to graft and/or patient loss. The aim of this study was to analyze the causes of and therapeutic approaches to urological complications in renal transplantation as they related to patient outcomes. A series of 1525 consecutive renal transplantations were performed over a 24-year period. Renal grafts were obtained in 814 cases from living-related and in 711 from cadaveric donors. A Lich-Gregoire ureterovesical reimplantation technique with minimal bladder wall dissection was employed in all cases. Ureteral stents were routinely used in cadaveric transplants and exceptionally among living-related grafts. Urological complications were classified according to the mechanism and site of urinary tract involvement: graft ureteropelvic junction obstruction/stenosis (A), ureteral obstruction/stenosis (B), ureterovesical anastomosis obstruction/stenosis (C), urinary leakage (D), and other (E). Overall, we encountered 96 urological complications (6.3%). Group C complications occurred in 29 cases (30.2%), followed by 27 cases (28.1%) for group B patients, 25 cases (26.0%) for group D, 12 cases (12.5%) for group A, and 3 cases (3.1%) for group E patients. Surgical intervention was required in 49 (51.0%) of all urological complications. The others (n = 47, 49.0%) were treated either conservatively or by minimally invasive procedures. A rapid diagnosis of urological complications, assisted by early posttransplant DTPA scans, routine ultrasonography, and especially prompt treatment, resulted in compensation of renal graft dysfunction in the vast majority (n = 90, 93.8%) of cases. Surgical techniques of graft retrieval and reimplantation are of utmost importance to minimize the incidence of urological complications. [Copyright &y& Elsevier]

Background: The shipment of human islets (IE) from processing centers to distant laboratories is beneficial for both research and clinical applications. The maintenance of islet viability and function in transit is critically important. Gas-permeable silicone rubber membrane (SRM) vessels reduce the risk of hypoxia-induced death or dysfunction during high-density islet culture or shipment. SRM vessels may offer additional advantages: they are cost-effective (fewer flasks, less labor needed), safer (lower contamination risk), and simpler (culture vessel can also be used for shipment). Method: IE were isolated from two manufacturing centers and shipped in 10-cm² surface area SRM vessels in temperature- and pressure-controlled containers to a distant center after at least 2 days of culture (n = 6). Three conditions were examined: low density (LD), high density (HD), and a microcentrifuge tube negative control (NC). LD was designed to mimic the standard culture density for IE preparations (200 IE/cm²), while HD was designed to have a 20-fold higher tissue density, which would enable the culture of an entire human isolation in 1-3 vessels. Upon receipt, islets were assessed for viability (measured by oxygen consumption rate normalized to DNA content [OCR/DNA)]), quantity (measured by DNA), and, when possible, potency and function (measured by dynamic glucose-stimulated insulin secretion measurements and transplants in immunodeficient B6 Rag+/- mice). Postshipment OCR/DNA was not reduced in HD vs LD and was substantially reduced in the NC condition. HD islets exhibited normal function postshipment. Based on the data, we conclude that entire islet isolations (up to 400,000 IE) may be shipped using a single, larger SRM vessel with no negative effect on viability and ex vivo and in vivo function. [ABSTRACT FROM AUTHOR]