M Wszoła

Machine Perfusion Preservation Improves Renal Allograft Survival

Machine perfusion (MP) has been used as the kidney preservation method in our center for over 10 years. The first, small (n = 74) prospective, single‐blinded randomized study comparing MP and Cold Storage (CS) showed that the incidence of delayed graft function was higher after CS. There have been no reports in the literature on the effect of storage modality on long‐term function of renal allografts. This paper presents an analysis of long‐term results of renal transplantation in 415 patients operated on between 1994 and 1999. Of those, 227 kidneys were MP‐stored prior to KTx. The control group consisted of 188 CS kidney transplants. Kidneys were not randomized to MP or to CS. Donor demographics, medical and biochemical data, cold ischemia time, HLA match and recipient data were collected. Standard triple‐drug immunosuppression was administered to both groups. Mortality, graft survival and incidence of return to hemodialysis treatment were analyzed. Despite longer cold ischemia time and poorer donor hemodynamics in MP group, 5‐year Kaplan‐Meier graft survival was better in MP‐stored than in CS‐stored kidneys (68.2% vs. 54.2%, p = 0.02). Conclusion: In this nonrandomized analysis, kidney storage by MP improved graft survival and reduced the number of patients who returned to dialysis.

One-year results of a prospective, randomized trial comparing two machine perfusion devices used for kidney preservation.

Studies have shown beneficial effects of machine perfusion (MP) on early kidney function and long‐term graft survival. The aim of this study was to investigate whether the type of perfusion device could affect outcome of transplantation of deceased donor kidneys. A total of 50 kidneys retrieved from 25 donors were randomized to machine perfusion using a flow‐driven (FD) device (RM3; Waters Medical Inc) or a pressure‐driven (PD) device (LifePort; Organ Recovery Systems), 24 of these kidneys (n = 12 pairs; 48%) were procured from expanded criteria donors (ECD). The primary endpoints were kidney function after transplantation defined using the incidence of delayed graft function (DGF), the number of hemodialysis sessions required, graft function at 12 months, and analyses of biopsy. DGF was similar in both groups (32%; 8/25). Patients with DGF in the FD group required a mean of 4.66 hemodialysis sessions versus 2.65 in the PD group (P = 0.005). Overall, 1‐year graft survival was 80% (20/25) vs. 96% (24/25) in the FD and PD groups. One‐year graft survival of ECD kidneys was 66% (8/12) in the FD group versus 92% (11/12) in the PD group. Interstitial fibrosis and tubular atrophy were significantly more common in the FD group – 45% (5/11) vs. 0% (0/9) (P = 0.03) in PD group. There were no differences in creatinine levels between the groups. Machine perfusion using a pressure‐driven device generating lower pulse stress is superior to a flow‐driven device with higher pulse stress for preserving kidney function.

Assessment of Kidneys Procured From Expanded Criteria Donors Before Transplantation

BACKGROUND Using expanded criteria donor (ECD) organs is 1 strategy to make more organs available for transplant. To reduce the number of posttransplant complications and failures, there is a need to create a comprehensive system of evaluation before transplantation, especially for kidneys harvested from ECD. The aim of this study was to assess the results of kidneys procured from ECD seeking to discover the most useful factors for kidney evaluation before transplantation. PATIENTS AND METHODS One hundred seventy-two patients received cadaveric renal transplants between January 1, 2006, and August 31, 2008. We collected data on donors, recipients, and perfusion parameters. We analyzed patient and graft survivals, as well as immediate, delayed, and slow graft function. Kidney recipient function was assessed by serum creatinine concentrations and by creatinine clearance calculated according to the Cockroft-Gault formula. Renal biopsy specimens were obtained in the perioperative periods 147 cases. RESULTS The overall 1-year graft survival was 86.9%. More than 25% of transplanted kidneys were harvested from ECD. There were no significant differences in patient survival between recipients of standard criteria donor kidneys (RSCDK) versus of expanded criteria donor kidneys (RECDK). One-year graft survival was higher among the RSCDK group than the RECDK group, namely, 94.4% versus 62.5%, (P = .004). There were no differences in the incidence of primary nonfunction or in delayed graft function between the groups. RECDK were more likely to show slow graft function (69.2% vs 37.8%; P = .033). A lower graft survival at 6 months after transplantation was observed among organs harvested from ECD compared with standard criteria donor (SCD) kidneys who showed histologic lesions or a flow at the fourth hour of machine perfusion below 0.4 mL/g. Using a logistic regression model, chronic histologic changes were shown to influence kidney survival at 6 months after transplantation. CONCLUSION There was no significant difference in patient survival between recipients of kidneys harvested from expanded versus standard criteria donors. ECD kidneys displayed lower graft survival rates. There was no significant difference in the incidence of delayed graft function between recipients of kidneys harvested from expanded versus standard criteria donors. Pretransplant evaluation of ECD kidneys should include 3 variables: donor parameters, histologic findings, and machine perfusion parameters.

Complications of Transplantation of Kidneys From Expanded-Criteria Donors

BACKGROUND Organ shortage is the primary barrier to kidney transplantation. To maximize organ use, organs from expanded-criteria donors (ECDs) have been used increasingly. Expanded-criteria donors are defined as individuals older than 60 years or older than 50 years with at least 2 of the following risk factors: hypertension, stroke as the cause of death, or serum creatinine concentration greater than 1.5 mg/dL. OBJECTIVE To assess the incidence of complications posttransplantation in ECD kidneys compared with kidneys from standard-criteria cadaveric donors (SCDs). PATIENTS AND METHODS One hundred seventy-two patients received cadaveric renal transplants between January 1, 2006, and August 31, 2008. Donor and recipient data were collected, as well as patient and graft survival and immediate, delayed, or slow graft function. Complication rates for lymphocele, urinary leak, thrombosis, hematoma, urinary tract infection, and cytomegalovirus infection were recorded. Follow-up was for 3 to 35 months, ending on November 30, 2008. RESULTS Overall, mean 1-year graft survival was 86.9%, and mean creatinine concentration was 1.58 mg/dL. One incidence of primary nonfunction (0.6%) was observed. More than 25% of transplanted kidneys were from ECDs. No significant differences were noted in postoperative complications between recipients of ECD or SCD organs. CONCLUSION The rate of complications in recipients of ECD and SCD kidneys is comparable.

Preservation of kidneys by machine perfusion influences gene expression and may limit ischemia/reperfusion injury

Context Machine perfusion improves graft survival. Histopathologic analysis reveals a lower incidence of chronic rejection and interstitial fibrosis in kidneys preserved with machine perfusion. Ischemic/reperfusion injury may help to explain these findings. Objective To assess the activation of genes correlated with ischemic/reperfusion injury in kidneys preserved under different conditions before transplant. Design/Patients Between 2005 and 2006, 69 kidney biopsy specimens were collected and patients were followed up for 5 years after that. Intervention Before transplant, kidneys were preserved with machine perfusion or cold storage. Donors from the machine perfusion and cold storage groups did not differ with regard to age, sex, or hemodynamic status. Recipients were divided into 5 groups: expanded criteria donor–machine perfusion (n = 16), standard criteria donor–machine perfusion (n = 10), expanded criteria donor–cold storage (n = 9), and standard criteria donor–cold storage (n = 27); 7 kidneys were retrieved from living related donors. Main Outcome Measures Biopsies were done 30 minutes after reperfusion. Interleukin-1β, vascular endothelial growth factor, heme oxygenase-1, and hypoxia-inducible factor–1 gene expression levels were analyzed. Results Mean expression levels of hypoxia-inducible factor–1α were significantly higher in the cold storage groups, and lower in the machine perfusion and living-related donor groups. Five-year graft survival was significantly (P < .05) lower in the expanded criteria donor–cold storage group (66%) than in the standard criteria donor–machine perfusion group (90%). Machine perfusion influences gene expression related to hypoxia during reperfusion and may improve the long-term results of kidney transplant.

Surgical site infections in the early posttransplant period after simultaneous pancreas-kidney transplantation.

OBJECTIVE Urinary tract infection (UTI) is among the common infection in simultaneous pancreas-kidney transplantation (SPKT). PATIENTS AND METHODS The study included 26 adult patients undergoing SPKT between September 2001 and December 2006. All the patients were followed prospectively for UTI during the first 4 weeks after surgery. Urine samples were investigated for bacteriologic cultures. The micro-organisms were identified in accordance with standard bacteriologic procedures. Susceptibility testing was carried out using Clinical and Laboratory Standards Institute (CLSI) procedures. RESULTS Among 77 urine specimens obtained from all recipients during the first month, there were 30 isolated bacterial strains. The most common were Gram-positive bacteria (53.3%) with predominance of enterococci (75%) associated with high levels of aminoglycoside resistant strains (HLAR; 58.3%) and vancomycin-resistant strains (VRE; 25%). Gram-negative bacteria were detected in 46.7% of positive cultures. CONCLUSIONS In our study, enterococci predominated as 75% of Gram-positive isolates. The increased proportion of multi-drug-resistant bacteria, which can caused severe UTI in patients after SPKT, may be due to the frequent use of prophylaxis of bacterial infections in patients.

Etiologic agents of bacteremia in the early period after simultaneous pancreas-kidney transplantation.

BACKGROUND Bacteremia is among the known complications in simultaneous pancreas-kidney transplantation (SPKT). This study evaluated the frequency of microbial isolates and their susceptibility profiles among cultures of clinical samples obtained from blood and from the tips of blood vessel catheters of 26 SPKT recipients suspected of bacteremia in the early posttransplant period. PATIENTS AND METHODS Data on microbiologic blood cultures of 26 adult patients undergoing SPKT were collected prospectively from 2001 to the end of 2006. The isolation and identification of cultured microorganisms were performed according to standard microbiological procedures and commercially available tests. The susceptibility of the strains to antibacterial agents was established by the Clinical and Laboratory Standards Institute guidelines. RESULTS All patients were followed prospectively for the first 4 weeks after surgery. Among 66 clinical samples, there were 23 microbial isolates from blood samples of 17 recipients and catheter tips of 12 recipients. The most common isolates were Gram-positive bacteria (73.9%) with domination of staphylococci (64.7%) and MRCNS strains (81.8%). Gram-negative bacteria comprised 17.4% of positive cultures, whereas yeast-like fungi, 8.7% with a predominance of Candida glabrata. CONCLUSION Our study showed predominately Gram-positive bacteria in 73.9% of isolates. The increased proportion of multi-drug-resistant bacteria and fungi to antimicrobial agents may be due to the frequent use of these agents for prophylaxis of bacterial infections in patients.

Simultaneous pancreas-kidney transplantation: analysis of donor factors

There are no urgent indications for simultaneous pancreas-kidney transplantation. So our policy is to harvest only a pancreas in good biologic condition. The criteria for acceptance of a pancreas donor are: age 15 to 40 years, ICU stay < 7 days, no clinical signs of infection, negative virologic status, no history of hypotension or cardiac arrest, serum amylase elevation below three times normal values, controllable hyperglycemia, no history of pancreatic disease, no history of abdominal trauma damaging the organ, no history of alcohol addiction, BMI < 25, no functional or anatomical lesions of the kidneys, and expected ischemia time less than 12 hours. The proper selection of a pancreas donor allows one to achieve good insulin secretion immediately after transplantation. In 2000 to 2002 all 20 pancreases transplanted at transplant center displayed immediate secretory function after transplantation.

Characteristics of Potential Living Kidney Donors and Recipients: Donor Disqualification Reasons—Experience of a Polish Center

INTRODUCTION Kidney transplantation is efficacious as a renal replacement, particularly pre-emptive living donation. In Poland, the rate of transplantation of living donor kidneys is only 3%. The aim of the study was to identify the most common reasons to disqualify a potential living kidney donor. METHODS We evaluated 124 kidney donor candidates for 111 potential recipients at 1 medical center for genders and ages of donor and recipient; thus relation, donor disqualification reasons, number of potential donors for a particular recipient, prior transplantations, and kidney vasculature. RESULTS The 111 recipients of ages 2-62 years had, 1, 2, or 3 potential donors were tested in 101, 1, and 7, cases respectively. We had 18.9% recipients referred for pre-emptive transplantation; 59.5% were on haemodialysis and 21.6% on peritoneal dialysis. In all, 89% recipients sought first kidney transplantations. Kidneys were procured from 49/124 (39.5%) of the initially evaluated donors. The full examination was completed by 92 potential donors with 68/124 donors disqualified early. Single and multiple renal arteries were detected in 56 and 36 potential donors, respectively. Donor disqualification was due to medical contraindications (39.7%), earlier transplantation from a deceased donor (25%), immunologic constraints (23.5%), donor consent withdrawn (6%) or psychological and social reasons (4.4%). CONCLUSIONS A considerable number of donor candidates are disqualified for medical reasons.

Successful outcome of transplant of kidneys recovered from a brain-dead liver transplant recipient: case report.

Few reports describing the use of organs donated by transplant recipients have been published. In this case report, kidneys procured from a brain-dead liver recipient were transplanted successfully. A 21-year-old man was referred for liver transplant after an overdose of acetaminophen. The patients kidney function was initially normal, with proper urine production and normal kidney laboratory parameters. On the third day after admission, the patients kidney laboratory parameters became elevated and hepatic encephalopathy requiring mechanical ventilation developed. An orthotopic liver transplant was performed the next day. The patient did not recover consciousness, and brain death was diagnosed on the third day after the liver transplant surgery. The maximum serum concentration of creatinine was 5.8 mg/dL (513 µmol/L) before kidney recovery, and urine production was normal. The kidneys were recovered with organ-perfusion support and were preserved by using machine perfusion. The kidneys were transplanted into 2 male recipients. Twelve months after transplant, the recipients remained in good health with satisfactory kidney function. This case demonstrates that transplanting kidneys recovered from liver transplant recipients is possible and beneficial, thus expanding the pool of potential donors.