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Regional and racial disparities in use of live non-directed donors. [Meeting Abstract]
Segev, Dorry L; Locke, Jayme E; Simpkins, Christopher E; Warren, Daniel S; Montgomery, Robert A
ISI:000246370200385
ISSN: 1600-6135
CID: 1983242
Minimizing risk associated with elderly liver donors by matching to preferred recipients
Segev, Dorry L; Maley, Warren R; Simpkins, Christopher E; Locke, Jayme E; Nguyen, Geoffrey C; Montgomery, Robert A; Thuluvath, Paul J
Elderly liver donors (ELDs) represent a possible expansion of the donor pool, although there is great reluctance to use ELDs because of reports that increasing donor age predicts graft loss and patient death. The goal of this study was to identify a subgroup of recipients who would be least affected by increased donor age and thus best suited to receive grafts from ELDs. A national registry of deceased donor liver transplants from 2002-2005 was analyzed. ELDs aged 70-92 (n = 1043) were compared with average liver donors (ALDs) aged 18-69 (n = 15,878) and ideal liver donors (ILDs) aged 18-39 (n = 6842). Recipient factors that modified the effect of donor age on outcomes were identified via interaction term analysis. Outcomes in recipient subgroups were compared using Kaplan-Meier survival analysis. Recipients preferred for ELD transplants were determined to be first-time recipients over the age of 45 with body mass index <35, non-status 1 registration, cold ischemic time <8 hours, and either hepatocellular carcinoma or an indication for transplantation other than hepatitis C. In preferred recipients, there were no differences in outcomes when ELD livers were used (3-year graft survival: ELD 75%, ALD 75%, ILD 77%, P > 0.1; 3-year patient survival: ELD 81%, ALD 80%, ILD 81%, P > 0.1). In contrast, there were significantly worse outcomes when ELD livers were used in nonpreferred recipients (3-year graft survival: ELD 50%, ALD 71%, ILD 75%, P < 0.001; 3-year patient survival: ELD 64%, ALD 77%, ILD 80%, P < 0.001). CONCLUSION: The risks of ELDs can be substantially minimized by appropriate recipient selection.
PMID: 17918247
ISSN: 1527-3350
CID: 1981982
Mullerian inhibiting substance regulates androgen-induced gene expression and growth in prostate cancer cells through a nuclear factor-kappaB-dependent Smad-independent mechanism
Tran, Trinh T; Segev, Dorry L; Gupta, Vandana; Kawakubo, Hirofumi; Yeo, Giminna; Donahoe, Patricia K; Maheswaran, Shyamala
Mullerian inhibiting substance (MIS), a member of the TGFbeta superfamily, causes regression of the Mullerian duct in male embryos. The presence of MIS type II and type I receptors in tissues and cell lines derived from the prostate suggests that prostate is a likely target for MIS. In this report, we demonstrate that MIS inhibits androgen-stimulated growth of LNCaP cells and decreases their survival in androgen-deprived medium by preventing cell cycle progression and inducing apoptosis. Expression of dominant-negative Smad1 reversed the ability of MIS to decrease LNCaP cell survival in androgen-deprived medium but not androgen-stimulated growth, whereas abrogation of nuclear factor-kappaB (NFkappaB) activation ablated the suppressive effects of MIS on both androgen-stimulated growth and androgen-independent survival. The effect of MIS on androgen-induced growth was not due to changes in androgen receptor expression. However, MIS suppressed androgen-stimulated transcription of prostate-specific antigen; ablation of NFkappaB activation reversed MIS-mediated suppression of prostate-specific antigen. These observations suggest that MIS regulates androgen-induced gene expression and growth in prostate cancer cells through a NFkappaB-dependent but Smad1-independent mechanism. Thus, MIS, in addition to potentially regulating prostate growth indirectly by suppressing testicular testosterone synthesis, may also be a direct regulator of androgen-induced gene expression and growth in the prostate at the cellular level.
PMID: 16740653
ISSN: 0888-8809
CID: 5129852
Domino paired kidney donation: a strategy to make best use of live non-directed donation
Montgomery, Robert A; Gentry, Sommer E; Marks, William H; Warren, Daniel S; Hiller, Janet; Houp, Julie; Zachary, Andrea A; Melancon, J Keith; Maley, Warren R; Rabb, Hamid; Simpkins, Christopher; Segev, Dorry L
PMID: 16876670
ISSN: 1474-547x
CID: 1981032
New options for patients with donor incompatibilities [Comment]
Montgomery, Robert A; Simpkins, Christopher E; Segev, Dorry L
PMID: 16858275
ISSN: 0041-1337
CID: 1981042
Successful transplantation of cadaveric polycystic liver: case report and review of the literature [Case Report]
Stewart, Zoe A; Kozlowski, Tomasz; Segev, Dorry L; Montgomery, Robert A; Klein, Andrew S
The number of candidates awaiting liver transplantation continues to exceed the available donor organ pool. This steadily increasing donor organ shortage calls for the widening of selection criteria for potential donor organs. Strategies to increase the number of liver allografts include liver splitting, use of donors over 70 years, use of steatotic donor livers, and reutilization of liver allografts after brain death of the first recipient. We report the successful use of a polycystic donor liver and review the experience with this donor population. We propose that the selective use of polycystic donor livers containing small (<5 cm) cysts with preserved liver parenchyma is safe and appropriate.
PMID: 16436973
ISSN: 0041-1337
CID: 1982042
Factors affecting graft survival after liver transplantation from donation after cardiac death donors
Lee, Kwang-Woong; Simpkins, Christopher E; Montgomery, Robert A; Locke, Jayme E; Segev, Dorry L; Maley, Warren R
BACKGROUND: Liver transplantation from donation after cardiac death (DCD) donors is an increasingly common approach for expansion of the donor organ supply. However, transplantation with DCD livers results in inferior graft survival. In this study, we examined donor and recipient characteristics that are associated with poor allograft outcomes and present a set of criteria that permit allograft survival that is comparable to that of donation after brain death (DBD) grafts in both low- and high-risk recipients. METHODS: The United Network for Organ Sharing/Organ Procurement and Transplantation Network Liver Transplantation Registry between January 1996 and March 2006 was investigated. Adult DCD liver transplants (n = 874) were included. RESULTS: A DCD risk index was developed using the statistically significant factors from a multivariate Cox model: history of previous transplantation, life support status at transplantation, donor age, donor warm ischemia time (DWIT), and cold ischemia time (CIT). Favorable DCD donor criteria were donor age < or =45 years, DWIT < or =15 min, and CIT < or =10 hr. Four risk groups were developed based upon index scores that showed different graft survival. Graft survival of the favorable DCD group (84.9% at 1 year, 75.2% at 3 years, and 69.4% at 5 years) was comparable to that for DBD liver transplantation irrespective of recipient condition. Increasing donor age was more highly predictive of poor outcomes in DCD compared to DBD, especially in recipients in poor preoperative condition. CONCLUSIONS: DCD livers from young donors with short DWIT and CIT should be given greater consideration in order to expand the number of available donor organs.
PMID: 17198260
ISSN: 0041-1337
CID: 1982022
The utility of TIPS in the management of Budd-Chiari syndrome
Molmenti, Ernesto P; Segev, Dorry L; Arepally, Aravind; Hong, Jenny; Thuluvath, Paul J; Rai, Rudra; Klein, Andrew S
BACKGROUND AND AIM/OBJECTIVE:Budd-Chiari syndrome (BCS) is a rare condition associated with hepatic venous outflow obstruction classically treated with portosystemic shunts or liver transplantation. Recent reports indicate promising results with the use of transjugular intrahepatic portosystemic shunts (TIPS) in the treatment of these patients. PATIENTS AND METHODS/METHODS:We reviewed a 10-year single-institution experience with TIPS in patients diagnosed with BCS. RESULTS:Eleven patients with BCS underwent TIPS procedures, 3 of whom carried a diagnosis of paroxysmal nocturnal hemoglobinuria, a relative contraindication for liver transplantation. One TIPS procedure was unsuccessful for technical reasons. No patient suffered mortality or major morbidity related to the TIPS procedure. The mean reduction of portal venous pressures was 43.7%, with a mean decrease of 73% in the pressure gradient. Of the 7 patients where long-term follow-up was available, 57% had shunts which remained patent but required several nonsurgical revisions for occlusion, with an average assisted patency of 37.5 months. CONCLUSIONS:TIPS is an effective modality in the treatment of patients with BCS, especially for those who are not candidates for liver transplantation. TIPS can be successfully used as a bridge to surgical portosystemic shunting, as well as liver transplantation, but may cause technical difficulties when performing transplantation.
PMCID:1357177
PMID: 15912047
ISSN: 0003-4932
CID: 5129842
ABO incompatible high-titer renal transplantation without splenectomy or anti-CD20 treatment [Case Report]
Segev, Dorry L; Simpkins, Christopher E; Warren, Daniel S; King, Karen E; Shirey, R Sue; Maley, Warren R; Melancon, J Keith; Cooper, Matthew; Kozlowski, Tomasz; Montgomery, Robert A
Most successful protocols for renal transplantation across ABO incompatible (ABOi) barriers have utilized splenectomy as part of the pre-conditioning process. We recently described successful ABOi transplantation using anti-CD20 monoclonal antibody in lieu of splenectomy. In the current study, we hypothesized that plasmapheresis (PP) and low dose CMV hyper-immunoglobulin (CMVIg) alone would be sufficient to achieve successful engraftment of ABOi kidneys. We describe four blood type incompatible patients who received live donor renal transplants from A1 (two patients), A2 (one patient), and B (one patient) donors. All patients started with antihuman globulin (AHG) phase titers of 64 or higher and were pre-conditioned with PP/CMVIg but not splenectomy or anti-CD20. All 4 patients underwent successful transplantation and have a mean current serum creatinine of 1.1 (range: 0.9-1.2). There were no episodes of antibody mediated rejection. Rapid allograft accommodation may limit the need for long-term antibody suppression provided by splenectomy or anti-CD20, thereby eliminating the added infectious risk of these modalities and removing another disincentive to ABOi transplantation.
PMID: 16162210
ISSN: 1600-6135
CID: 1981072
Characterization of waiting times in a simulation of kidney paired donation
Segev, Dorry L; Gentry, Sommer E; Melancon, J Keith; Montgomery, Robert A
A national kidney paired donation (KPD) program will substantially increase transplant opportunities for recipients with blood type incompatible or cross-match positive donors. It seems likely that donor-recipient pairs with certain blood types, races or restrictions will wait longer than others for a match, although no data exist to confirm this assumption. We simulated patients and characterized the predicted waiting times for different blood type sub-groups, as well as the effects of patient-imposed restrictions on waiting time. We also compared waiting times of different racial sub-groups. Almost all patients with panel-reactive antibody (PRA) less than 80% match within a few months in a national KPD program, with the longest waiting time seen by O recipients with AB donors. Highly sensitized patients wait considerably longer, especially those unwilling to travel or accept older donors, and those with AB or B donors may not match in a timely manner. Although patients are better served by matching in a combined pool than within their own race, racial inequalities exist and bonus points can offset some of these differences. These data provide the first waiting time predictions that can aid patients with incompatible donors in choosing between KPD and desensitization, and can also facilitate planning for a national KPD program.
PMID: 16162194
ISSN: 1600-6135
CID: 1981082