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ABO-incompatible deceased donor liver transplantation in the United States: a national registry analysis
Stewart, Zoe A; Locke, Jayme E; Montgomery, Robert A; Singer, Andrew L; Cameron, Andrew M; Segev, Dorry L
In the United States, ABO-incompatible liver transplantation (ILT) is limited to emergent situations when ABO-compatible liver transplantation (CLT) is unavailable. We analyzed the United Network for Organ Sharing database of ILT performed from 1990-2006 to assess ILT outcomes for infant (0-1 years; N = 156), pediatric (2-17 years; N = 170), and adult (> 17 years; N = 667) patients. Since 2000, the number of ILT has decreased annually, and there has been decreased use of blood type B donors and increased use of blood type A donors. Furthermore, ILT graft survival has improved for all age groups in recent years, beyond the improved graft survival attributable to era effect based on comparison to respective age group CLT. On matched control analysis, graft survival was significantly worse for adult ILT as compared to adult CLT. However, infant and pediatric ILTs did not have worse graft survival versus age-matched CLT. Adjusted analyses identified age-specific characteristics impacting ILT graft loss. For infants, transplant after 2000 and donor age < 9 years were associated with reduced risk of ILT graft loss. For pediatric patients, female recipient sex and donor age > 50 years were associated with increased risk of ILT graft loss. For adults, life support, repeat transplant, split grafts, and hepatocellular carcinoma were associated with increased risk of ILT graft loss. The current study identifies important trends in ILT in the United States in the modern immunosuppression era, as well as specific recipient, donor, and graft characteristics impacting ILT graft survival that could be utilized to guide ILT organ allocation in exigent circumstances. Liver Transpl 15:883-893, 2009. (c) 2009 AASLD.
PMID: 19642117
ISSN: 1527-6473
CID: 1981872
Successful liver transplantation for Budd-Chiari syndrome in a patient with paroxysmal nocturnal hemoglobinuria treated with the anti-complement antibody eculizumab [Case Report]
Singer, Andrew L; Locke, Jamye E; Stewart, Zoe A; Lonze, Bonnie E; Hamilton, James P; Scudiere, Jennifer R; Anders, Robert A; Rother, Russell P; Brodsky, Robert A; Cameron, Andrew M
Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired hemolytic anemia caused by somatic mutations in the phosphatidylinositol glycan-complementation class A gene and the resulting absence of a key complement regulatory protein, CD59. Affected red blood cells in patients with PNH undergo intravascular complement-mediated lysis with resulting anemia, hemoglobinuria, and venous thromboses. Hepatic venous outflow thrombosis [Budd-Chiari syndrome (BCS)] is especially common in PNH patients and often fatal. The few case reports of outcomes in patients undergoing liver transplant for BCS secondary to PNH detail instances of recurrent BCS as well as early thrombotic portal vein occlusion and hepatic artery thrombosis requiring retransplantation. PNH is therefore generally considered a contraindication to liver transplantation. Here we present the first report of a patient with PNH and BCS undergoing successful liver transplantation while receiving eculizumab, a humanized monoclonal antibody that blocks the activation of the terminal complement at C5.
PMID: 19399743
ISSN: 1527-6473
CID: 2209372
Histidine-tryptophan-ketoglutarate (HTK) is associated with reduced graft survival of deceased donor kidney transplants
Stewart, Z A; Lonze, B E; Warren, D S; Dagher, N N; Singer, A L; Montgomery, R A; Segev, D L
Single-center studies have reported equivalent outcomes of kidney allografts recovered with histidine-tryptophan-ketoglutarate (HTK) or University of Wisconsin (UW) solution. However, these studies were likely underpowered and often unadjusted, and multicenter studies have suggested HTK preservation might increase delayed graft function (DGF) and reduce graft survival of renal allografts. To further inform clinical practice, we analyzed the United Network for Organ Sharing (UNOS) database of deceased donor kidney transplants performed from July 2004 to February 2008 to determine if HTK (n = 5728) versus UW (n = 15 898) preservation impacted DGF or death-censored graft survival. On adjusted analyses, HTK preservation had no effect on DGF (odds ratio [OR] 0.99, p = 0.7) but was associated with an increased risk of death-censored graft loss (hazard ratio [HR] 1.20, p = 0.008). The detrimental effect of HTK was a relatively late one, with a strong association between HTK and subsequent graft loss in those surviving beyond 12 months (HR 1.43, p = 0.007). Interestingly, a much stronger effect was seen in African-American recipients (HR 1.55, p = 0.024) than in Caucasian recipients (HR 1.18, p = 0.5). Given recent studies that also demonstrate that HTK preservation reduces liver and pancreas allograft survival, we suggest that the use of HTK for abdominal organ recovery should be reconsidered.
PMID: 19298449
ISSN: 1600-6143
CID: 1980672
ABO incompatible renal transplantation: a paradigm ready for broad implementation
Montgomery, Robert A; Locke, Jayme E; King, Karen E; Segev, Dorry L; Warren, Daniel S; Kraus, Edward S; Cooper, Matthew; Simpkins, Christopher E; Singer, Andrew L; Stewart, Zoe A; Melancon, J Keith; Ratner, Lloyd; Zachary, Andrea A; Haas, Mark
The requirements for potent immunosuppression coupled with the formidable risk of irreversible antibody-mediated rejection (AMR) have thus far limited the expansion of ABO incompatible (ABOi) kidney transplantation. We present a retrospective review of our single-center experience with 60 consecutive ABOi kidney transplants and describe the evolution of our treatment protocol to one that consists only of a brief escalation in immunosuppression without long-term B-cell suppression from splenectomy or anti-CD20. The 1-, 3-, and 5-year graft survival rates for the cohort were 98.3%, 92.9%, and 88.7%, respectively, which is comparable with United Network for Organ Sharing data for compatible live donor transplants. No instances of hyperacute rejection were observed, and no grafts were lost secondary to AMR. In fact, fewer than 15% of the patients experienced a clinical episode of AMR, and rejections were mild. Elimination of B-cell ablative therapies did not result in an increased incidence of AMR. Excellent graft function persists with a current median creatinine clearance of 60 mL/min. The findings of this study and the relatively simple therapeutic regimen used should facilitate widespread application of ABOi kidney transplantation resulting in one of the most rapid escalations in access to organs in the modern era of kidney transplantation.
PMID: 19384174
ISSN: 1534-6080
CID: 1980682
Kidney transplantation in previous heart or lung recipients
Lonze, B E; Warren, D S; Stewart, Z A; Dagher, N N; Singer, A L; Shah, A S; Montgomery, R A; Segev, D L
Outcomes after heart and lung transplants have improved, and many recipients survive long enough to develop secondary renal failure, yet remain healthy enough to undergo kidney transplantation. We used national data reported to United Network for Organ Sharing (UNOS) to evaluate outcomes of 568 kidney after heart (KAH) and 210 kidney after lung (KAL) transplants performed between 1995 and 2008. Median time to kidney transplant was 100.3 months after heart, and 90.2 months after lung transplant. Renal failure was attributed to calcineurin inhibitor toxicity in most patients. Outcomes were compared with primary kidney recipients using matched controls (MC) to account for donor, recipient and graft characteristics. Although 5-year renal graft survival was lower than primary kidney recipients (61% KAH vs. 73.8% MC, p < 0.001; 62.6% KAL vs. 82.9% MC, p < 0.001), death-censored graft survival was comparable (84.9% KAH vs. 88.2% MC, p = 0.1; 87.6% KAL vs. 91.8% MC, p = 0.6). Furthermore, renal transplantation reduced the risk of death compared with dialysis by 43% for KAH and 54% for KAL recipients. Our findings that renal grafts function well and provide survival benefit in KAH and KAL recipients, but are limited in longevity by the general life expectancy of these recipients, might help inform clinical decision-making and allocation in this population.
PMID: 19260837
ISSN: 1600-6143
CID: 1980712
Histidine-Tryptophan-Ketoglutarate (HTK) is associated with reduced graft survival in deceased donor livers, especially those donated after cardiac death
Stewart, Z A; Cameron, A M; Singer, A L; Montgomery, R A; Segev, D L
Single-center studies have reported that liver allograft survival is not affected by preservation in histidine-tryptophan-ketoglutarate (HTK) versus University of Wisconsin (UW) solution. We analyzed the UNOS database of liver transplants performed from July, 2004, through February, 2008, to determine if preservation with HTK (n = 4755) versus UW (n = 12 673) impacted graft survival. HTK preservation of allografts increased from 16.8% in 2004 to 26.9% in 2008; this was particularly striking among donor after cardiac death (DCD) allografts, rising from 20.7% in 2004 to 40.9% in 2008. After adjusting for donor, recipient and graft factors that affect graft survival, HTK preservation was associated with an increased risk of graft loss (HR 1.14, p = 0.002), especially with DCD allografts (HR 1.44, P = 0.025) and those with cold ischemia time over 8 h (HR 1.16, P = 0.009). Furthermore, HTK preservation was associated with a 1.2-fold higher odds of early (< 30 days) graft loss as compared to UW preservation (OR 1.20, p = 0.012), with a more pronounced effect on allografts with cold ischemia time over 8 h (OR 1.31, p = 0.007), DCD allografts (OR 1.63, p = 0.09) and donors over 70 years (OR 1.67, p = 0.081). These results suggest that the increasing use of HTK for abdominal organ preservation should be reexamined.
PMID: 19067658
ISSN: 1600-6143
CID: 1981902
The use of antibody to complement protein C5 for salvage treatment of severe antibody-mediated rejection [Case Report]
Locke, J E; Magro, C M; Singer, A L; Segev, D L; Haas, M; Hillel, A T; King, K E; Kraus, E; Lees, L M; Melancon, J K; Stewart, Z A; Warren, D S; Zachary, A A; Montgomery, R A
Desensitized patients are at high risk of developing acute antibody-mediated rejection (AMR). In most cases, the rejection episodes are mild and respond to a short course of plasmapheresis (PP) / low-dose IVIg treatment. However, a subset of patients experience severe AMR associated with sudden onset oliguria. We previously described the utility of emergent splenectomy in rescuing allografts in patients with this type of severe AMR. However, not all patients are good candidates for splenectomy. Here we present a single case in which eculizumab, a complement protein C5 antibody that inhibits the formation of the membrane attack complex (MAC), was used combined with PP/IVIg to salvage a kidney undergoing severe AMR. We show a marked decrease in C5b-C9 (MAC) complex deposition in the kidney after the administration of eculizumab.
PMID: 18976298
ISSN: 1600-6143
CID: 1980752
Histidine-tryptophan-ketoglutarate (HTK) is associated with reduced graft survival in pancreas transplantation
Stewart, Z A; Cameron, A M; Singer, A L; Dagher, N N; Montgomery, R A; Segev, D L
Prior single-center studies have reported that pancreas allograft survival is not affected by preservation in histidine-tryptophan-ketoglutarate (HTK) versus University of Wisconsin (UW) solution. To expand on these studies, we analyzed the United Network for Organ Sharing (UNOS) database of pancreas transplants from July 2004, through February 2008, to determine if preservation with HTK (N = 1081) versus UW (N = 3311) impacted graft survival. HTK preservation of pancreas allografts increased significantly in this time frame, from 15.4% in 2004 to 25.4% in 2008. After adjusting for other recipient, donor, graft and transplant center factors that impact graft survival, HTK preservation was independently associated with an increased risk of pancreas graft loss (hazard ratio [HR] 1.30, p = 0.014), especially in pancreas allografts with cold ischemia time (CIT) >or=12 h (HR 1.42, p = 0.017). This reduced survival with HTK preservation as compared to UW preservation was seen in both simultaneous pancreas-kidney (SPK) transplants and pancreas alone (PA) transplants. Furthermore, HTK preservation was also associated with a 1.54-fold higher odds of early (<30 days) pancreas graft loss as compared to UW (OR 1.54, p = 0.008). These results suggest that the increasing use of HTK for abdominal organ preservation should be re-examined.
PMID: 18986383
ISSN: 1600-6143
CID: 1980742
Histidine-Tryptophan-Ketoglutarate (HTK) Is Associated with Reduced Graft Survival of Deceased Donor Kidney Transplants. [Meeting Abstract]
Stewart, Zoe A; Lonze, Bonnie E; Warren, Daniel S; Dagher, Nabil N; Singer, Andrew L; Montgomery, Robert A; Segev, Dorry L
ISI:000265068800149
ISSN: 1600-6135
CID: 1982612
Use of Histidine-Tryptophan-Ketoglutarate for Liver Allograft Preservation Reduces Graft Survival and Is Not Cost-Effective Resource Utilization. [Meeting Abstract]
Stewart, Zoe A; Cameron, Andrew M; Dagher, Nabil N; Singer, Andrew L; Montgomery, Robert A; Segev, Dorry L
ISI:000265068800250
ISSN: 1600-6135
CID: 1982632