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John F Renz

Publications and source records attributed to John F Renz.

18 recordsLinked to original sources
PubMed2006

Extended-donor criteria liver allografts.

Extended-donor criteria liver allografts do not meet traditional criteria for transplantation. Although these organs offer immediate expansion of the donor pool, transplantation of extended-donor criteria liver allografts increases potential short- and long-term risk to the recipient. This risk may manifest as impaired allograft function or donor-transmitted disease. Guidelines defining this category of donor, level of acceptable risk, principles of consent, and post-transplantation surveillance have not been defined. This article reviews the utilization, ethical considerations, and outcomes of extended-donor criteria liver allografts.

Donor Selection↗
PubMed2005

Infectious enteritis after intestinal transplantation: incidence, timing, and outcome.

BACKGROUND: The study reviews the incidence, timing, and outcome of infectious enteritis (IE) after intestinal transplantation (ITx). METHODS: A retrospective review of all patients who underwent ITx at a single institution between 1991 and 2003 was undertaken using database and medical records. Standard statistical analyses were performed. RESULTS: Of 33 ITx recipients, 13 (39%) developed 20 culture- or biopsy-proven episodes of IE. Recipient demographics included the following: 10 males, median age 34 (10-585) months, 11 liver + intestine grafts, and two isolated intestine grafts. Infections were diagnosed a median of 76 days (32-1,800 days) after ITx. There were 14 viral (one cytomegalovirus, eight rotavirus, four adenovirus, one Epstein-Barr virus), three bacterial (Clostridium difficile), and three protozoal (one Giardia lamblia, two Cryptosporidium) infections. The bacterial infections tended to present earlier than the viral infections, and the most frequent presenting symptom was diarrhea. Complete resolution was achieved in 17 (94%) incidences with the appropriate antimicrobial or conservative therapy. It was interesting that there were seven rejection episodes documented by biopsy at the approximate time of diagnosis of IE. There were two graft losses: one because of adenoviral enteritis and one because of rejection after rotavirus enteritis. Three-year patient survival is 74% with no deaths directly attributable to IE. CONCLUSIONS: IE can occur in 39% of recipients after ITx. Viral agents are the cause in two thirds of the cases. With supportive care and appropriate treatment, resolution is possible in the majority of cases. Differentiating rejection and infection on histopathology can be difficult and relies on cultures and immunostaining.

Adult↗
PubMed2005

A critical evaluation of hepatic resection in cirrhosis: optimizing patient selection and outcomes.

Hepatic resection has long been the mainstay of treatment of primary liver cancers, particularly hepatocellular carcinoma (HCC). Because of the high incidence of cirrhosis in patients with HCC, the use of resection was initially limited by the ability of the cirrhotic liver to sustain the surgical insult and the mass reduction. Today, hepatectomy in cirrhosis is undergoing a remarkable evolution. Although surgical and anesthetic improvements have increased the safety of this option, the rapid development of alternative therapies has decreased the need for it. Local excision for small HCC is likely to be replaced by image-guided, percutaneous ablative techniques. Furthermore, total replacement of a cirrhotic liver may be a more effective long-term cure than resection. Unquestionably, resection remains the optimal approach for patients with large tumors and healthy underlying liver function. The role of rapidly evolving new approaches will remain the subject of intensive inquiry in the years to come. In this report, we have attempted to clarify current practice with respect to the evaluation, selection, and technique of resection in cirrhosis, and identify areas of active inquiry.

Carcinoma, Hepatocellular↗
PubMed2005

Utilization of extended donor criteria liver allografts maximizes donor use and patient access to liver transplantation.

OBJECTIVE: The objective of this study was to evaluate the effect of systematic utilization of extended donor criteria liver allografts (EDC), including living donor allografts (LDLT), on patient access to liver transplantation (LTX). SUMMARY BACKGROUND DATA: Utilization of liver allografts that do not meet traditional donor criteria (EDC) offer immediate expansion of the donor pool. EDC are typically allocated by transplant center rather than regional wait-list priority (RA). This single-institution series compares outcomes of EDC and RA allocation to determine the impact of EDC utilization on donor use and patient access to LTX. METHODS: The authors conducted a retrospective analysis of 99 EDC recipients (49 deceased donor, 50 LDLT) and 116 RA recipients from April 2001 through April 2004. Deceased-donor EDC included: age >65 years, donation after cardiac death, positive viral serology (hepatitis C, hepatitis B core antibody, human T-cell lymphotrophic), split-liver, hypernatremia, prior carcinoma, steatosis, and behavioral high-risk donors. Outcome variables included patient and graft survival, hospitalization, initial graft function, and complication categorized as: biliary, vascular, wound, and other. RESULTS: EDC recipients were more frequently diagnosed with hepatitis C virus or hepatocellular carcinoma and had a lower model for end-stage liver disease (MELD) score at LTX (P < 0.01). Wait-time, technical complications, and hospitalization were comparable. Log-rank analysis of Kaplan-Meier survival estimates demonstrated no difference in patient or graft survival; however, deaths among deceased-donor EDC recipients were frequently the result of patient comorbidities, whereas LDLT and RA deaths resulted from graft failure (P < 0.01). EDC increased patient access to LTX by 77% and reduced pre-LTX mortality by over 50% compared with regional data (P < 0.01). CONCLUSION: Systematic EDC utilization maximizes donor use, increases access to LTX, and significantly reduces wait-list mortality by providing satisfactory outcomes to select recipients.

Adolescent↗
PubMed2005

Predictors of candidate maturation among potential living donors.

The shortage of deceased donor allografts and improved outcomes in partial organ transplantation have led to widespread application of adult-to-adult living donor liver transplantation. Donor selection limits overall utilization of this technique and predictors of candidate maturation have been inadequately studied to date. We therefore collected data on 237 consecutive potential donors including their age, sex, ethnicity, relationship to the recipient, education, employment and religious beliefs and practices. Of these 237 candidates, 91 (38%) were excluded for medical and psychosocial reasons, 53 (22%) withdrew from the process predonation and 93 (39%) underwent partial liver donation. In multivariate analyses, the relationship between the donor and the recipient was highly predictive of successful donation. For pediatric recipients, no parents voluntarily withdrew from the evaluation process. For adult recipients, spouses are the most likely to donate, followed by parents, children and siblings. Additional predictors for donation included self-description as religious but not regularly practicing, part-time employment and higher education. Race, ethnicity, gender and age did not predict donation in multivariate analysis. Further understanding of the complex decision to donate may improve donation rates as well as permit more efficient and cost-effective donor evaluation strategies.

Adolescent↗
PubMed2004

Split-liver transplantation in the United States: outcomes of a national survey.

OBJECTIVE: Assess application and outcomes of split-liver transplantation within the United States. SUMMARY BACKGROUND DATA: While a theoretically attractive mechanism to increase cadaver organ supply, split-liver transplantation has been infrequently applied. The American Society of Transplant Surgeons, in an attempt to gather preliminary data on split-liver transplantation, performed a data protected survey of transplant centers participating in the U.S. Scientific Registry for Transplant Recipients. METHODS: Between April 2000 and May 2001, 89 surgical teams were surveyed. Elicited data included graft type, recipient status, procurement method, graft sharing, graft outcomes, recipient outcomes, and experience with cadaver, whole-organ transplantation. RESULTS: Eighty-three surgical teams reported data on 207 left lateral segment, 152 right trisegment, 15 left lobe, and 13 right lobe grafts. The split procedure was performed ex vivo in 54% and in situ in 46% of grafts. Complications were frequent in all graft types with biliary and vascular complications equally distributed between grafts procured by either technique. Primary nonfunction, graft failure, and recipient death correlated with transplant status. CONCLUSIONS: Split-liver transplantation has been principally applied to adult-child pairs with at least one recipient critically ill. Biliary and vascular complications account for the majority of morbidity in grafts procured by either split technique with graft failure and recipient death observed more frequently in critically ill recipients. Enhanced utilization and improved results may be possible through improved information sharing and modification of allocation criteria.

Adult↗
PubMed2003

Analysis of failure in living donor liver transplantation: differential outcomes in children and adults.

Over the past decade we have reported excellent outcomes in pediatric living-donor liver transplantation (LDLT) with recipient survival exceeding 90%. Principles established in these patients were extended to LDLT in adults. To compare outcomes in donors and recipients between adult and pediatric LDLT in a single center, we reviewed patient records of 45 LDLT performed between 1/98 and 2/01: 23 adult LDLT (54 +/- 6.5 yr) and 22 pediatric LDLT (33.7 +/- 53.5 months). Preoperative liver function was worse in adults (International Normalized Ratio [INR] 1.5 +/- 0.4 vs. INR 1.2 +/- 0.5; p = 0.032). 4 adults (17%) met criteria for status 1 or 2A. Only 1 child was transplanted urgently. Analysis included descriptive statistics and Kaplan-Meier estimation. Donor mortality was 0% with 1 re-exploration, 2.4%. Median hospital stay (LOS) was 6.0 days (range, 4-12 days). Donor morbidity and LOS did not differ by sex, extent of hepatectomy, or adult and pediatric LDLT ( p = 0.49). In contrast, recipient outcomes were worse for adults. Adult 1 year graft survival was 65% (3 retransplants [ReTx], 5 deaths) vs. 91% for children (1 ReTx, 1 death) p = 0.02. Graft losses in adults were due to sepsis (n = 3), small for size (n = 2), suicide, and hepatic artery thrombosis (HAT), whereas in children graft losses were due to portal thrombosis and total parenteral nutrition (TPN) liver failure. Biliary leaks occurred in 22% of adults and 9% of children. Hepatic vein obstruction occurred in 17% of adults and in none of the children. Median LOS was comparable (adult, 16.5 days (range, 7-149 days); child, 17 days (range, 10-56 days), p = 0.2). Graft function (total bilirubin (TBili) < 5mg/dl, INR < 1.2, aspartate aminotransferase (AST) < 100 U/l) normalizing by day 4 in children and by day 14 in adults. Adults fared worse, with an array of problems not seen in children, in particular, hepatic vein obstruction and small-for-size syndrome. Biliary leaks were diagnosed later in adults and were lethal in 3 cases; this was later avoided with biliary drainage in adult recipients. Finally, use of LDLT in decompensated adults led to death in 3 of 4 patients, and should be restricted to elective use.

Adolescent↗
PubMed2003

Changing faces of liver transplantation: partial-liver grafts for adults.

The utilization of partial-liver grafts for transplantation of adults represents an evolution from strategies designed to increase pediatric organ supply that have been justified by increased organ-waiting times and morbidity of adult transplant candidates. These techniques, which include adult-to-adult living-donor and split-liver transplantation, mandate particular surgical and medical considerations, as partial-liver grafts predispose to unique complications resulting from anatomic variations, technical considerations, and recipient physiology. Adult-to-adult living-donor liver transplantation has been successfully reported throughout the world; however, the magnitude of the donor operation has resulted in serious morbidity and donor mortality that have stimulated an ethical debate as to the future of this procedure. The limitations encountered in the application of adult-to-adult, living-donor liver transplantation have renewed interest in the successful implementation of split-liver transplantation between two adults from one adult cadaver donor. This manuscript details current technical considerations for the performance of adult-to-adult living-donor and split-liver transplantation, summarizes current outcomes, and explores the ethical dilemma of living-donation.

Asia↗
PubMed2003

The conventional technique in in-situ split-liver transplantation.

Split-liver transplantation are innovative surgical techniques of graft creation that expand the cadaver donor pool and decrease reliance upon living-donation. To date, split-liver transplantation has been principally applied to pediatric recipients with excellent outcomes. Significant decreases in pediatric wait-list times, wait-list morbidity, and lower utilization of living-donation at centers that routinely implement split-liver transplantation have led to renewed interest in expanding these techniques to include two adult recipients from one adult cadaver donor. This article details technical considerations of the conventional in situ split procedure for the creation of a pediatric left lateral segment graft and an adult trisegment graft, and summarizes current outcomes.

Adult↗
PubMed2003

Split-liver transplantation: a review.

Split-liver transplantation (SLT), a procedure where one cadaver liver is divided to provide for two recipients, offers immediate expansion of the existing cadaver donor pool. To date, the principal beneficiaries of SLT have been adult/pediatric recipient pairs with excellent outcomes reported; however, the current scarcity of cadaver organs has renewed interest in expanding these techniques to include two adult recipients from one adult cadaver donor. Significant obstacles to the widespread application of SLT exist and must be resolved by the transplant community before greater utilization can be realized. This manuscript reviews the historic background, surgical techniques, current results, and obstacles impeding further application of SLT.

Adult↗
PubMed2003

Acquired hemophilia A after liver transplantation: a case report.

It is well recognized that orthotopic liver transplantation rapidly corrects the coagulation disorder observed in patients with hemophilia A or B combined with end-stage liver disease; however, the transmission of hemophilia from a donor to a transplant recipient has not been reported previously. We describe a patient who developed acquired hemophilia A after liver transplantation due to the unknown presence of factor VIII inhibitor in the donor. The resulting coagulation disorder was unresponsive to standard factor replacement therapy, and was ultimately corrected with retransplantation. Hemophiliac donors should not be precluded from organ donation, though the presence of factor VIII inhibitor should be actively sought before organ procurement. High levels of factor VIII inhibitor represents an absolute contraindication to liver donation.

Factor VIII↗
PubMed2003

Multivisceral and isolated intestinal procurement techniques.

Improved outcomes in multivisceral and isolated intestinal transplantation have generated increased demand for these procedures. Enhanced recognition of potential multivisceral/intestinal donors and widespread application of advanced organ procurement techniques is necessary in the current climate of organ scarcity. This manuscript details the multivisceral and isolated intestinal procurement techniques currently performed at the University of California Los Angeles.

Colon↗
PubMed2003

One hundred in situ split-liver transplantations: a single-center experience.

OBJECTIVE: To identify predictors of graft and recipient survival from a single-institution series of in situ split-liver transplantations and compare outcomes to living donor and whole organs for adults and children. SUMMARY BACKGROUND DATA: Split-liver transplantation is a surgical technique that creates 2 allografts from a single cadaver donor. We have applied split-liver transplantation to all indications and categories of medical urgency for initial as well as retransplantation to expand the current donor pool and decrease reliance upon living donation. METHODS: A retrospective analysis was conducted of 100 consecutive in situ split-liver transplantations yielding a left lateral segment and right trisegment graft that were performed at the University of California Los Angeles between 9/91 and 02/03. These 100 transplantations generated 190 allografts for transplantation into 105 children and 60 adults, with the sharing of 25 allografts among transplant centers across the United States. Outcomes and incidence of complications were compared with living donor and whole organ recipients receiving liver transplantation during the same time period with independent predictors of split-liver graft and recipient survival identified by multivariate analysis. RESULTS: The incidence of biliary and vascular complications observed in recipients of left lateral segment grafts created by split-liver transplantation was not statistically different from recipients of left lateral segment grafts created from living donation or children receiving whole-organ grafts from pediatric donors. Kaplan-Meier survival estimations of left lateral segment graft and recipient survival also demonstrated no statistical difference among split-liver, living donor, and whole-organ recipients. Right trisegment grafts from split-liver transplantation demonstrated a 10% incidence of biliary and 7% incidence of vascular complications. Long-term graft function was excellent with patient and graft survival equal to 1086 recipients of cadaver whole-organ grafts from donors ages 10-40 years who underwent transplant operations during the same time period. Predictors of split-liver transplantation graft and recipient survival included United Network for Organ Sharing status at transplantation, indication, occurrence of a complication, donor creatinine, and donor length of hospitalization. CONCLUSIONS: Split-liver transplantation is an effective mechanism for immediate expansion of the cadaver donor pool that can reduce dependence upon living donation in adults and children.

Adolescent↗
PubMed2002

Allograft rejection in pediatric liver transplantation: Comparison between cadaveric and living related donors.

The aim of this study was to determine whether living related liver transplantation has an immunological advantage compared with cadaveric liver transplants in children. The records of 100 pediatric primary liver transplant recipients performed between January 1992 and December 1998 at the University of California, San Francisco Medical Center, were reviewed retrospectively. Ten children who died or required a second graft within the first 14 post-operative days were excluded from this study group. Two children with combined kidney-liver transplants were also excluded. As a result, the study group included 51 children in the cadaveric liver transplantation (CLT) group and 37 children in the living-related liver transplantation (LRLT) group. Until 1995, primary immunosuppression consisted of cyclosporin A, azathioprine and steroids. Since 1995, primary immunosuppression consisted of cyclosporin A, mycophenolate mofetil and steroids. Actuarial graft survival rates at 1, 2 and 5 yrs were 90%, 80.9% and 80.9% in the CLT group vs. 94.6%, 91.6% and 78.5% in the LRLT group, respectively (NS). Rejection was diagnosed in 40 of 51 cadaveric first grafts (78.4%) and 25 of 37 living-related primary grafts (67.6%). Rejection episodes were diagnosed greater than 1 yr post-transplantation in 11 of 51 cadaveric first grafts (21.6%) and none of 37 living-related primary grafts (0%) (p < 0.05). LRLT succeeded in reducing the immunosuppressive therapy compared with CLT at 24 months after transplantation (p < 0.05). The overall incidence of rejection and graft survival rate were comparable in CLT and LRLT; however, rejection episodes in LRLT recipients diagnosed greater than 1 yr post-transplant were significantly fewer than CLT recipients. LRLT have a partial immunological advantage compared with CLT.

Adolescent↗
PubMed2002

Optimizing the use of donated cadaver livers: analysis and policy development to increase the application of split-liver transplantation.

The American Society of Transplant Surgeons and the American Society of Transplantation jointly sponsored a conference in Crystal City, Virginia, on March 28th and 29th, 2001, to explore mechanisms for maximizing the cadaver-organ donor pool. Participants from transplantation medicine, surgery, organ procurement organizations, the general public, and government convened to address expanding utilization of each organ type. The committee assigned to review liver organ utilization identified multiple practices that could expand the potential donor pool including non-heart beating donors, marginal grafts, efficient allocation of cadaver organs, and wider application of split-liver transplantation. This article details the data reviewed by the liver committee and their recommendations on policy development for the expanded application of split-liver transplantation.

Cadaver↗
PubMed2002

Donor health assessment after living-donor liver transplantation.

OBJECTIVE: To elicit donor opinions on liver living donation through use of a survey that protected the anonymity of the respondent and to assay long-term (follow-up > 1 year) donor health by a widely recognized instrument for health assessment. SUMMARY BACKGROUND DATA: Living-donor liver transplantation is an accepted technique for children that has recently been extended to adults. Limited donor outcomes data suggest favorable results, but no outcomes data have been reported using an instrument that elicits an anonymous response from the donor or employs a widely recognized health survey. METHODS: Forty-one living-donors between June 1992 and June 1999 were identified and included in this study, regardless of specific donor or recipient outcome. Each donor received a 68-question survey and a standard McMaster Health Index. RESULTS: Survey response was 80%. All donors were satisfied with the information provided to them before donation. Eighty-eight percent of donors initially learned of living donation only after their child had been diagnosed with liver disease: 44% through the transplant center, 40% by popular media, 12% by their pediatrician, and 4% by their primary care physician. Physical symptoms, including pain and the surgical wound, were recurrent items of concern. Perception of time to "complete" recovery were less than 3 months (74%), 3 to 6 months (16%), and more than 6 months (10%). Donors' return to physical activities was shown by above-mean McMaster physical scores; scores for social and emotional health were not different from population data. There were no reported changes in sexual function or menstruation after donation, and five of six donors procreated. CONCLUSIONS: Donors overwhelmingly endorsed living donation regardless of recipient outcome or the occurrence of a complication. Eighty-nine percent advocated "increased" application of living donation beyond "emergency situations," and no donor responded that living donation should be abandoned or that he or she felt "forced" to donate.

Adult↗
PubMed2001

Liver transplantation for nonviral, nonmalignant diseases:problem of recurrence.

Liver transplantation has evolved rapidly from an experimental treatment to universally accepted therapy for end-stage liver disease. Indications for liver transplantation have expanded with the evolution of the procedure to include metabolic,viral, malignant, and acquired liver failure. As long-term liver transplant recipient follow-up data become available, the development of recurrent liver disease within the transplanted allograft is an increasing dilemma. The value of the transplant procedure must be assessed within the context of survival as well as the potential for recurrent disease and the associated need for re-transplantation. This study represents a compilation of data obtained from adult patients undergoing liver transplantation for nonviral, nonmalignant etiologies at the University of California San Francisco and a comparison of our data with other centers. Between February 1988 and January 1997, 654 liver transplants were performed on 623 patients. From this group, 406 recipients were identified as meeting study inclusion criteria: age above 18 years, and transplantation for a nonmalignant, nonviral etiology of liver failure. Indications for liver transplantation included primary biliary cirrhosis (n = 65), primary sclerosing cholangitis (n = 49), autoimmune hepatitis (n = 37),Budd-Chiari syndrome (n = 7), cryptogenic cirrhosis (n = 88),and alcoholic liver disease (n = 160). Mean follow-up within the diagnostic groups ranged from 4.9 to 5.6 years. Evaluation of clinical,immunosuppressive, and pathologic data for each diagnostic group was performed to determine the incidence, time to recurrence, clinical presentation, and sequelae of disease recurrence.

Adult↗