Prevention of the Osmotic Demyelination Syndrome After Liver Transplantation: A Multidisciplinary Perspective

The osmotic demyelination syndrome (ODS) is a serious neurologic condition that occurs in the setting of rapid correction of hyponatremia. It presents with protean manifestations, from encephalopathy to the "locked-in" syndrome. ODS can complicate liver transplantation (LT), and its incidence may increase with the inclusion of serum sodium as a factor in the Mayo End-Stage Liver Disease score. A comprehensive understanding of risk factors for the development of ODS in the setting of LT, along with recommendations to mitigate the risk of ODS, are necessary. The literature to date on ODS in the setting of LT was reviewed. Major risk factors for the development of ODS include severe pretransplant hyponatremia (serum sodium [SNa] < 125 mEq/L), the magnitude of change in SNa pre- versus posttransplant, higher positive intraoperative fluid balance, and the presence of postoperative hemorrhagic complications. Strategies to reduce the risk of ODS include correcting hyponatremia pretransplant via fluid restriction and/or ensuring an appropriate rate of increase from the preoperative SNa via close attention to fluid and electrolyte management both during and after surgery. Multidisciplinary management involving transplant hepatology, nephrology, neurology, surgery, and anesthesiology/critical care is key to performing LT safely in patients with hyponatremia.

Efficacy and Safety Outcomes of Extended Criteria Donor Kidneys by Subtype: Subgroup Analysis of BENEFIT-EXT at 7 Years After Transplant

The phase III Belatacept Evaluation of Nephroprotection and Efficacy as First-Line Immunosuppression Trial-Extended Criteria Donors Trial (BENEFIT-EXT) study compared more or less intensive belatacept-based immunosuppression with cyclosporine (CsA)-based immunosuppression in recipients of extended criteria donor kidneys. In this post hoc analysis, patient outcomes were assessed according to donor kidney subtype. In total, 68.9% of patients received an expanded criteria donor kidney (United Network for Organ Sharing definition), 10.1% received a donation after cardiac death kidney, and 21.0% received a kidney with an anticipated cold ischemic time ≥24 h. Over 7 years, time to death or graft loss was similar between belatacept- and CsA-based immunosuppression, regardless of donor kidney subtype. In all three donor kidney cohorts, estimated mean GFR increased over months 1-84 for belatacept-based treatment but declined for CsA-based treatment. The estimated differences in GFR significantly favored each belatacept-based regimen versus the CsA-based regimen in the three subgroups (p < 0.0001 for overall treatment effect). No differences in the safety profile of belatacept were observed by donor kidney subtype.

Long-Term Outcomes in Belatacept- Versus Cyclosporine-Treated Recipients of Extended Criteria Donor Kidneys: Final Results From BENEFIT-EXT, a Phase III Randomized Study

In the Belatacept Evaluation of Nephroprotection and Efficacy as First-Line Immunosuppression Trial-Extended Criteria Donors (BENEFIT-EXT), extended criteria donor kidney recipients were randomized to receive belatacept-based (more intense [MI] or less intense [LI]) or cyclosporine-based immunosuppression. In prior analyses, belatacept was associated with significantly better renal function compared with cyclosporine. In this prospective analysis of the intent-to-treat population, efficacy and safety were compared across regimens at 7 years after transplant. Overall, 128 of 184 belatacept MI-treated, 138 of 175 belatacept LI-treated and 108 of 184 cyclosporine-treated patients contributed data to these analyses. Hazard ratios (HRs) comparing time to death or graft loss were 0.915 (95% confidence interval [CI] 0.625-1.339; p = 0.65) for belatacept MI versus cyclosporine and 0.927 (95% CI 0.634-1.356; p = 0.70) for belatacept LI versus cyclosporine. Mean estimated GFR (eGFR) plus or minus standard error at 7 years was 53.9 ± 1.9, 54.2 ± 1.9, and 35.3 ± 2.0 mL/min per 1.73 m² for belatacept MI, belatacept LI and cyclosporine, respectively (p < 0.001 for overall treatment effect). HRs comparing freedom from death, graft loss or eGFR <20 mL/min per 1.73 m² were 0.754 (95% CI 0.536-1.061; p = 0.10) for belatacept MI versus cyclosporine and 0.706 (95% CI 0.499-0.998; p = 0.05) for belatacept LI versus cyclosporine. Acute rejection rates and safety profiles of belatacept- and cyclosporine-based treatment were similar. De novo donor-specific antibody incidence was lower for belatacept (p ≤ 0.0001). Relative to cyclosporine, belatacept was associated with similar death and graft loss and improved renal function at 7 years after transplant and had a safety profile consistent with previous reports.

Belatacept Conversion in an HIV-Positive Kidney Transplant Recipient With Prolonged Delayed Graft Function

We report an HIV-positive renal transplant recipient with delayed graft function who was converted from tacrolimus to belatacept in an attempt to improve renal function. The patient had kidney biopsies at 4 and 8 weeks posttransplant that revealed acute tubular necrosis and mild fibrosis. After 14 weeks of delayed function, belatacept was initiated and tacrolimus was weaned off. Shortly after discontinuing tacrolimus, renal function began to improve. The patient was able to discontinue dialysis 21 weeks posttransplant. HIV viral load was undetectable at last follow-up. To our knowledge, this is the first report of belatacept use in a patient with HIV.

Early Liver Transplantation for Severe Alcoholic Hepatitis in the United States--A Single-Center Experience

Early liver transplantation (LT) in European centers reportedly improved survival in patients with severe alcoholic hepatitis (AH) not responding to medical therapy. Our aim was to determine if a strategy of early LT for severe AH could be applied successfully in the United States. We reviewed 111 patients with severe AH at our center from January 2012 to January 2015. The primary end point was mortality at 6 months or early LT, with a secondary end point of alcohol relapse after LT. Survival was compared between those receiving early LT and matched patients who did not. Using a process similar to the European trial, 94 patients with severe AH not responding to medical therapy were evaluated for early LT. Overall, 9 (9.6%) candidates with favorable psychosocial profiles underwent early LT, comprising 3% of all adult LT during the study period. The 6-month survival rate was higher among those receiving early LT compared with matched controls (89% vs 11%, p<0.001). Eight recipients are alive at a median of 735 days with 1 alcohol relapse. Early LT for severe AH can achieve excellent clinical outcomes with low impact on the donor pool and low rates of alcohol relapse in highly selected patients in the United States.

Tailoring the endovascular management of transplant renal artery stenosis

In this study we analyze the different types of endovascular interventions (EVIs) in de novo transplant renal artery stenosis (TRAS) and its anatomical subtypes to examine any variation in recovery of allograft function, blood pressure control, EVI patency and allograft survival with respect to EVI type (DES: drug-eluting stent, BMS: bare-metal stent, PTA: percutaneous transluminal angioplasty). Forty-five patients underwent a total of 50 primary EVIs (DES: 18, BMS: 26, PTA: 6). Patients were stratified according to medical co-morbidities, graft characteristics, biopsy results, clinical presentation and TRAS anatomic subtypes (anastomotic: 26, postanastomotic: 17, bend-kink: 2). There was significant improvement in allograft function and mean arterial blood pressure (MAP) control across all interventions (pre-EVI-creatinine [CR]: 2.8 ± 1.4, post-EVI-Cr: 2.1 ± 0.7, p < 0.001; pre-EVI-MAP: 117 ± 16, post-EVI-MAP: 112 ± 17, p = 0.03) with no significant difference among EVI types. There was no significant difference in allograft survival with respect to EVI type. Patency was significantly higher in EVIs performed with DES and BMS compared to PTA (p = 0.001). In the postanastomotic TRAS subtype, patency rates were significantly higher in DES compared to BMS (p = 0.012) in vessels of comparable reference diameter (≤5 mm).

Long-term exposure to belatacept in recipients of extended criteria donor kidneys

Patients in the BENEFIT-EXT study received extended criteria donor kidneys and a more intensive (MI) or less intensive (LI) belatacept immunosuppression regimen, or cyclosporine A (CsA). Patients who remained on assigned therapy through year 3 were eligible to enter a long-term extension (LTE) study. Three hundred four patients entered the LTE (n = 104 MI; n = 113 LI; n = 87 CsA), and 260 continued treatment through year 5 (n = 91 MI; n = 100 LI; n = 69 CsA). Twenty patients died during the LTE (n = 5 MI; n = 9 LI; n = 6 CsA), and eight experienced graft loss (n = 2 MI; n = 1 LI; n = 5 CsA). Three patients experienced an acute rejection episode (n = 2 MI; n = 1 LI). The incidence rate of serious adverse events, viral infections and fungal infections was similar across groups during the LTE. There were four cases of posttransplant lymphoproliferative disorder (PTLD) from the beginning of the LTE to year 5 (n = 3 LI; n = 1 CsA); two of three PTLD cases in the LI group were in patients who were seronegative for Epstein-Barr virus (EBV(-)) at transplantation. Mean ± SD calculated GFR at year 5 was 55.9 ± 17.5 (MI), 59.0 ± 29.1 (LI) and 44.6 ± 16.4 (CsA) mL/min/1.73 m(2) . Continued treatment with belatacept was associated with a consistent safety profile and sustained improvement in renal function versus CsA over time.

Association of intraoperative blood pressure instability with adverse outcomes after liver transplantation

BACKGROUND

Blood pressure derangements are common in orthotopic liver transplantation (OLT), and are potentially associated with adverse outcomes if they are sustained. While this concept is often believed to be true, few have rigorously demonstrated the validity of this claim, especially in likely vulnerable OLT patients.

METHODS

We retrospectively investigated 827 patients who underwent OLT to determine the magnitude of these hemodynamic associations with adverse outcomes. The median value of the mean arterial pressure (MAP) and the fractional change in the median MAP between subsequent epochs (FCM) were calculated for every 5-minute epoch intraoperatively. Epochs were classified according to prespecified ranges of MAP and fractional changes in MAP (lability) between epochs. Multivariate stepwise logistic regression was used to model associations of risk factors and epochs of intraoperative blood pressure (BP) instability with primary (30-day mortality and/or graft failure) and secondary adverse outcomes.

RESULTS

Primary adverse outcomes occurred in 10.9% and 12.2% of patients for 30-day mortality and 30-day graft failure, respectively. Independent hemodynamic predictors for 30-day mortality and graft failure included sustained periods of MAP <50 mmHg and BP lability where the MAP changed >25%. All of these values were statistically significant.

CONCLUSION

Although severe intraoperative hypotension and BP lability during OLT are often observed in current practice as consequences of major surgical manipulations and patient vulnerability, these are likely not benign conditions based on this retrospective analysis. Prospective trials are warranted to investigate the possibility that interventions tailored to avoidance of hypotension and BP lability may improve outcomes.

Human monoclonal antibody MBL-HCV1 delays HCV viral rebound following liver transplantation: a randomized controlled study

Rapid allograft infection complicates liver transplantation (LT) in patients with hepatitis C virus (HCV). Pegylated interferon-α and ribavirin therapy after LT has significant toxicity and limited efficacy. The effect of a human monoclonal antibody targeting the HCV E2 glycoprotein (MBL-HCV1) on viral clearance was examined in a randomized, double-blind, placebo-controlled pilot study in patients infected with HCV genotype 1a undergoing LT. Subjects received 11 infusions of 50 mg/kg MBL-HCV1 (n=6) or placebo (n=5) intravenously with three infusions on day of transplant, a single infusion on days 1 through 7 and one infusion on day 14 after LT. MBL-HCV1 was well-tolerated and reduced viral load for a period ranging from 7 to 28 days. Median change in viral load (log10 IU/mL) from baseline was significantly greater (p=0.02) for the antibody-treated group (range -3.07 to -3.34) compared to placebo group (range -0.331 to -1.01) on days 3 through 6 posttransplant. MBL-HCV1 treatment significantly delayed median time to viral rebound compared to placebo treatment (18.7 days vs. 2.4 days, p<0.001). As with other HCV monotherapies, antibody-treated subjects had resistance-associated variants at the time of viral rebound. A combination study of MBL-HCV1 with a direct-acting antiviral is underway.

Three-year outcomes from BENEFIT-EXT: a phase III study of belatacept versus cyclosporine in recipients of extended criteria donor kidneys

Recipients of extended-criteria donor (ECD) kidneys have poorer long-term outcomes compared to standard-criteria donor kidney recipients. We report 3-year outcomes from a randomized, phase III study in recipients of de novo ECD kidneys (n = 543) assigned (1:1:1) to either a more intensive (MI) or less intensive (LI) belatacept regimen, or cyclosporine. Three hundred twenty-three patients completed treatment by year 3. Patient survival with a functioning graft was comparable between groups (80% in MI, 82% in LI, 80% in cyclosporine). Mean calculated GFR (cGFR) was 11 mL/min higher in belatacept-treated versus cyclosporine-treated patients (42.7 in MI, 42.2 in LI, 31.5 mL/min in cyclosporine). More cyclosporine-treated patients (44%) progressed to GFR <30 mL/min (chronic kidney disease [CKD] stage 4/5) than belatacept-treated patients (27-30%). Acute rejection rates were similar between groups. Posttransplant lymphoproliferative disorder (PTLD) occurrence was higher in belatacept-treated patients (two in MI, three in LI), most of which occurred during the first 18 months; four additional cases (3 in LI, 1 in cyclosporine) occurred after 3 years. Tuberculosis was reported in two MI, four LI and no cyclosporine patients. In conclusion, at 3 years after transplantation, immunosuppression with belatacept resulted in similar patient survival, graft survival and acute rejection, with better renal function compared with cyclosporine. As previously reported, PTLD and tuberculosis were the principal safety findings associated with belatacept in this study population.

Anti-lymphocyte therapy successfully controls late "cholestatic" rejection in pediatric liver transplant recipients

Rejection is independently associated with liver graft loss in children. We report the successful rescue of grafts using ATG+/-OKT3 in late rejection associated with cholestasis. Retrospective chart review was performed after IRB approval. Between 2003 and 2010, 14 pediatric liver transplant recipients received anti-lymphocyte treatment for "cholestatic" rejection. Median age at transplantation was 12.7 yr (range 0.9-23.4), eight were boys, and immunosuppression was tacrolimus based. Median time from transplantation to rejection was five yr (range 1.1-10.5). Median peak total bilirubin was 11.1 mg/dL (range 1.4-18). All showed moderate to severe acute rejection and hepatocellular cholestasis on histology. ATG/OKT3 was started as first-line therapy in six and in the remaining eight as second-line therapy after failure of pulse steroids. Thirteen responded with normalization of aminotransferases and bilirubin, median time 16 wk (range 7-112); one non-adherent recipient has still not achieved normal graft function at last follow-up. Patient survival is 100%, with no re-transplantation and no post-transplant lymphoproliferative disease, median follow-up 2.9 yr (range 1.1-7.2). Cholestasis associated with acute rejection occurring late after liver transplantation may herald steroid resistance. First-line therapy with anti-lymphocyte preparations, prophylactic anti-microbial therapy, and close monitoring allow excellent rates of patient and graft survival.

A phase III study of belatacept versus cyclosporine in kidney transplants from extended criteria donors (BENEFIT-EXT study)

Recipients of extended criteria donor (ECD) kidneys are at increased risk for graft dysfunction/loss, and may benefit from immunosuppression that avoids calcineurin inhibitor (CNI) nephrotoxicity. Belatacept, a selective costimulation blocker, may preserve renal function and improve long-term outcomes versus CNIs. BENEFIT-EXT (Belatacept Evaluation of Nephroprotection and Efficacy as First-line Immunosuppression Trial-EXTended criteria donors) is a 3-year, Phase III study that assessed a more (MI) or less intensive (LI) regimen of belatacept versus cyclosporine in adult ECD kidney transplant recipients. The co-primary endpoints at 12 months were composite patient/graft survival and a composite renal impairment endpoint. Patient/graft survival with belatacept was similar to cyclosporine (86% MI, 89% LI, 85% cyclosporine) at 12 months. Fewer belatacept patients reached the composite renal impairment endpoint versus cyclosporine (71% MI, 77% LI, 85% cyclosporine; p = 0.002 MI vs. cyclosporine; p = 0.06 LI vs. cyclosporine). The mean measured glomerular filtration rate was 4-7 mL/min higher on belatacept versus cyclosporine (p = 0.008 MI vs. cyclosporine; p = 0.1039 LI vs. cyclosporine), and the overall cardiovascular/metabolic profile was better on belatacept versus cyclosporine. The incidence of acute rejection was similar across groups (18% MI; 18% LI; 14% cyclosporine). Overall rates of infection and malignancy were similar between groups; however, more cases of posttransplant lymphoproliferative disorder (PTLD) occurred in the CNS on belatacept. ECD kidney transplant recipients treated with belatacept-based immunosuppression achieved similar patient/graft survival, better renal function, had an increased incidence of PTLD, and exhibited improvement in the cardiovascular/metabolic risk profile versus cyclosporine-treated patients.

A comparison of long-term survivals of simultaneous pancreas-kidney transplant between African American and Caucasian recipients with basiliximab induction therapy

African Americans (AA) have traditionally been thought to have higher immunologic risk than Caucasians (CA) for rejection and allograft loss. The impact of ethnicity on the outcome of simultaneous pancreas-kidney (SPK) transplant with basiliximab induction has not been reported. In this study, we retrospectively analyze the long-term results of 36 AA and 55 CA recipients of primary SPK. The actual patient survival rates of AA and CA groups were 91.7% vs. 90.1% at 1 year, 93.3% vs. 88.1% at 3 years, and 94.4% vs. 83.3% at 5 years. The actual kidney survival of AA and CA were 91.7% vs. 89.1% at 1 year, 90% vs. 81% at 3 years, and 83.3% vs. 75% at 5 years. The actual pancreas survival of AA and CA were 88.9% vs. 85.5% at 1 year, 83.3% vs. 78.6% at 3 years and 72.2% vs. 70.8% at 5 years. Death-censored analyses also found no difference in pancreas and kidney graft survival rates over 5 years. Higher rejection rate, but the same low CMV infection, and comparable quality of graft function were noted in AA group. AA may not have worse long-term outcomes than CA recipients of SPK with basiliximab induction and tacrolimus (TAC), mycophenolate acid (MFA) and steroid maintenance immunotherapy.

Once-daily tacrolimus extended-release formulation: 1-year post-conversion in stable pediatric liver transplant recipients

The pharmacokinetics, safety and tolerability of a once-daily formulation of tacrolimus (tacrolimus extended-release formulation; XL formerly referred to as MR or MR4) were assessed in 18 stable pediatric liver transplant recipients who were converted from the twice-a-day formulation of tacrolimus (TAC) to XL. Patients received their twice-a-day dose of TAC on study days 1 through 7. Beginning on the morning of study day 8, patients were converted to XL on a 1:1 (mg:mg) basis for their total daily dose, and were maintained on a once-daily AM dosing regimen using the same therapeutic monitoring and patient care techniques employed with TAC. Based on pharmacokinetic profiles obtained on study days 7 (TAC) and 14 (XL), steady state exposure (AUC(0-24)) was equivalent between XL and TAC; the mean XL/TAC ratio for lnAUC(0-24) was 100.9% (90% CI: 90.8%, 112.1%). AUC(0-24) and C(min) were strongly correlated at steady state (correlation coefficient: XL 0.90, TAC 0.94). During the first year post-conversion, there were no cases of acute rejection, discontinuation of XL, graft loss or death. The safety profile of XL was consistent with that known for TAC. These results support the safe and convenient conversion of pediatric liver transplant recipients from twice-a-day TAC to once-daily XL.

Identification of Ultrastructural Changes in Liver Allografts of Patients Experiencing Primary Nonfunction

BACKGROUND

Primary nonfunction (PNF) after liver transplantation is fatal without timely retransplantation. PNF has been associated with many risk factors, but the etiology remains unknown in most cases. Using electron microscopy, we examined the hepatic ultrastructure of donor allografts in patients experiencing PNF and compared the findings with a well-matched group of other donor allografts.

MATERIALS AND METHODS

Archival paraffin-embedded pre- and post-reperfusion donor liver biopsies were examined by electron microscopy in 10 patients with PNF and in 10 controls, matched by donor age +/- 5 years, gender, cold ischemic time +/- 1 hour, and donor cause of death. Mitochondria, endoplasmic reticulum, sinusoidal endothelial cells, and the glycogen content of the cells were assessed. The donors' serum peak transaminases, bilirubin and sodium levels, as well as the recipient age and serum creatinine were compared.

RESULTS

There were no significant differences in recipient age at the time of transplantation, peak recipient serum creatinine, donor peak serum transaminase, sodium or bilirubin levels. In all cases, the endoplasmic reticulum and sinusoidal endothelial cells were ultrastructurally normal. Hepatocytes had variable degrees of glycogen pooling. Hepatic steatosis and intramitochondrial inclusions cells were present in 5/10 PNF compared to 0/10 controls patients on preperfusion liver biopsy (P = .17).

CONCLUSION

Liver allografts from patients suffering from PNF can have mitochondrial ultrastructural changes on preperfusion biopsies.

Conversion of stable liver transplant recipients from a twice-daily Prograf-based regimen to a once-daily modified release tacrolimus-based regimen

INTRODUCTION

Modified release (MR) tacrolimus is an extended release formulation administered once daily. The purpose of this pharmacokinetic (PK) study was to evaluate tacrolimus exposure in stable liver transplant recipients converted from Prograf twice a day to MR tacrolimus once daily.

METHODS

This was an open-label, multicenter study with a single sequence, four-period crossover design. Eligible patients were 18 to 65 years of age, >6 months posttransplant with stable renal and hepatic function and receiving stable doses of Prograf twice a day for >2 weeks prior to enrollment. Patients received Prograf twice a day on days 1 to 14 and 29 to 42. Patients were converted to the same milligram-for-milligram daily dose of MR once daily on days 15 to 28 and 43 to 56. Twenty-four-hour PK profiles were obtained on days 14, 28, 42, and 56. Laboratory and safety parameters were also evaluated.

RESULTS

Of 70 patients, 62 completed all four PK profiles. The AUC0-24 of tacrolimus was comparable for Prograf twice a day (days 14 and 42) and MR tacrolimus once daily (days 28 and 56). The 90% confidence intervals for MR tacrolimus versus Prograf at steady state (days 28 and 56 vs days 14 and 42) was 0.85 to 0.92 for AUC0-24. MR tacrolimus was well tolerated with a safety profile comparable to that of Prograf. AUC0-24 was highly correlated to Cmin for Prograf (day 14, r = .93; Day 42, r = .89) and for MR tacrolimus (day 28, r = .93; day 56, r = .92). Renal and liver function remained stable. One patient experienced acute rejection.

CONCLUSION

The steady-state tacrolimus exposure of MR tacrolimus once daily is equivalent to Prograf twice a day after a milligram-for-milligram conversion in stable liver transplant recipients.

Noninvasive preoperative evaluation of biliary anatomy in right-lobe living donors with mangafodipir trisodium-enhanced MR cholangiography

BACKGROUND

Accurate preoperative radiologic imaging is essential to assess the vascular and biliary anatomy of right-lobe living donors and to ensure their safety. Volumetric magnetic resonance cholangiography (MRCP) using Mangafodipir trisodium (Mn-DPDP) contrast has been recently proposed to evaluate the biliary anatomy of living donor candidates.

METHODS

During their preoperative evaluation, 18 right-lobe (RL) living donors underwent 3D Mn-DPDP-enhanced MRCP in addition to the standard thin- and thick-slab MRCP imaging. Immediately prior to hepatectomy all 18 RL donors underwent intraoperative cholangiography (IOC) via the cystic duct. We compared the efficacy of these different radiologic techniques to actual intraoperative IOC findings.

RESULTS

Sixty-eight intrahepatic bile ducts were identified on IOC, 67(98.5%) by Mn-DPDP-enhanced 3D MRCP, 41 (60%) by thick-slab SSFSE imaging, and 35 (51%) by thin-slice SSFSE imaging. Mn-DPDP-enhanced 3D MRCP detected 100% (n = 5) of the anomalous origins of the right bile duct, and thick-slab MRCP detected 20% (n = 1) and thin-slab MRCP detected 0%. Anterior and posterior right intrahepatic bile ducts were identified by MnDPDP-enhanced 3D MRCP 100% of the time, by thick-slab SSFSE imaging 35% of the time, and by thin-slice SSFSE imaging only 12% of the time.

CONCLUSIONS

Mn-DPDP-enhanced 3D MRCP imaging was highly sensitive and specific in identifying variants of the intrahepatic bile ducts. This technique should be included in the standard protocol of preoperative radiologic evaluation of RL living donor candidates.

Clinical presentations of soft-tissue infections and surgical site infections

Skin and soft-tissue infections that usually follow minor traumatic events or surgical procedures are caused by a wide spectrum of bacteria. Less frequently, the infections occur spontaneously, which often is clinically confusing and leads to delays in diagnosis. Most of the infections are self-limited and easily treated with local measures and/or antibiotics. Others are life-threatening, requiring prompt diagnosis and aggressive surgical debridement in addition to the wise choice of antibiotic agents to limit tissue loss and preserve life. Many survivors experience critical tissue losses that may require changes in lifestyle as well as major reconstructive cosmetic surgery. Involvement of antibiotic-resistant gram-positive microorganisms in these infections only increases the difficulty of their treatment and may have a significant influence on the ultimate outcome.

One hundred nine living donor liver transplants in adults and children: a single-center experience

OBJECTIVE

To summarize the evolution of a living donor liver transplant program and the authors' experience with 109 cases.

SUMMARY BACKGROUND DATA

The authors' institution began to offer living donor liver transplants to children in 1993 and to adults in 1998.

METHODS

Donors were healthy, ages 18 to 60 years, related or unrelated, and ABO-compatible (except in one case). Donor evaluation was thorough. Liver biopsy was performed for abnormal lipid profiles or a history of significant alcohol use, a body mass index more than 28, or suspected steatosis. Imaging studies included angiography, computed tomography, endoscopic retrograde cholangiopancreatography, and magnetic resonance imaging. Recipient evaluation and management were the same as for cadaveric transplant.

RESULTS

After ABO screening, 136 potential donors were evaluated for 113 recipients; 23 donors withdrew for medical or personal reasons. Four donor surgeries were aborted; 109 transplants were performed. Fifty children (18 years or younger) received 47 left lateral segments and 3 left lobes; 59 adults received 50 right lobes and 9 left lobes. The average donor hospital stay was 6 days. Two donors each required one unit of banked blood. Right lobe donors had three bile leaks from the cut surface of the liver; all resolved. Another right lobe donor had prolonged hyperbilirubinemia. Three donors had small bowel obstructions; two required operation. All donors are alive and well. The most common indications for transplant were biliary atresia in children (56%) and hepatitis C in adults (40%); 35.6% of adults had hepatocellular carcinoma. Biliary reconstructions in all children and 44 adults were with a Roux-en-Y hepaticojejunostomy; 15 adults had duct-to-duct anastomoses. The incidence of major vascular complications was 12% in children and 11.8% in adult recipients. Children had three bile leaks (6%) and six (12%) biliary strictures. Adult patients had 14 (23.7%) bile leaks and 4 (6.8%) biliary strictures. Patient and graft survival rates were 87.6% and 81%, respectively, at 1 year and 75.1% and 69.6% at 5 years. In children, patient and graft survival rates were 89.9% and 85.8%, respectively, at 1 year and 80.9% and 78% at 5 years. In adults, patient and graft survival rates were 85.6% and 77%, respectively, at 1 year.

CONCLUSION

Living donor liver transplantation has become an important option for our patients and has dramatically changed our approach to patients with liver failure. The donor surgery is safe and can be done with minimal complications. We expect that living donor liver transplants will represent more than 50% of our transplants within 3 years.

Graft function and survival depend primarily on host factors in compromised recipient models of orthotopic liver transplantation in the rat

BACKGROUND

Experimental models of liver transplantation use normal recipients, although most patients undergoing liver transplantation suffer from acute or chronic liver failure. This study was designed to analyze the outcome of orthotopic liver transplantation in compromised rat hosts.

METHODS

Recipient animals were either rats with D-galactosamine-induced acute or rats with chronic liver failure secondary to common bile duct ligation. Liver damage was evaluated by monitoring enzymes, bilirubin, ammonia levels, prothrombin, thrombin time, and cytokines. In vivo function of hepatocytes and sinusoidal endothelial cells were evaluated by indocyanine green and hyaluronic acid uptake. Transplantation was performed in normal, acute, and chronic liver failure rats at different time points using either freshly harvested or cold-preserved syngeneic livers.

RESULTS

Survival with fresh grafts decreased significantly when transplants were performed 48 hr after the induction of acute liver failure. No rats with acute liver failure survived transplantation with grafts stored for 12 or 24 hr although in chronic failure survival was more 80%. Survival of acute liver failure rats receiving 6 hr preserved grafts was 16.6% compared with 83.3% observed with fresh grafts transplanted at the same time point after D-galactosamine injection. Elevated tumor necrosis factor-alpha and interleukin-1beta levels as well as impaired sinusoidal endothelial cell function were detected in acute liver failure rats with 6 h preserved grafts.

CONCLUSION

These results suggest that preoperative status and different host factors have a significant effect on outcome and graft function after liver transplantation in rats.

Utility of CT angiography for evaluation of living kidney donors

We reviewed our initial experience with helical computed tomography (CT) angiography in the evaluation of living kidney donors which, until now, has necessitated arteriography. Nineteen donors (12 women, 7 men) have had their renal anatomy evaluated solely by CT angiography preoperatively. All scans demonstrated normal collecting systems and single ureters. Five donors (26%) had supernumerary renal arteries. Fourteen donors had single, 4 donors had two, and 1 donor had three renal arteries. Helical CT demonstrated small polar vessels in several donors. Two donors (10%) had supernumerary renal veins. Accuracy of vascular anatomy defined on CT was 90% when confirmed at operation. Anatomically all CT findings were consistent with operative findings except in 1 donor who was found to have a 0.8 cm lesion near the renal hilum. At our institution, the total charges for selective renal arteriography are $3845 and for helical CT with three-dimensional (3-D) reconstruction are $1546. The amount of contrast dye (approximately 100 mL) is equivalent. Patients uniformly reported that the CT scan was a convenient and painless procedure. The accuracy of helical CT angiography is equivalent to arteriography in assessing renal vascular anatomy (with the additional benefit of imaging venous and parenchymal anatomy). Charges for helical CT are 59% less. There is greater patient acceptance and potentially less morbidity associated with the non-invasive nature of helical CT. We believe that CT angiography is the radiologic procedure of choice for the assessment of renal anatomy in potential living kidney donors.

Differential in vivo recovery of sinusoidal endothelial cells, hepatocytes, and Kupffer cells after cold preservation and liver transplantation in rats

BACKGROUND

The injury resulting from cold preservation/reperfusion primarily affects sinusoidal endothelial cells, while hepatocytes are thought to be less vulnerable; morphological changes and increased cytokine release suggest that Kupffer cells are activated. We evaluated the extent of functional damage to the different cell types in the liver after cold preservation and transplantation. Additionally, we analyzed in vivo the patterns of functional recovery of all three cell types over the first week after transplantation in Lewis rats.

METHODS

We evaluated the in vivo uptake of hyaluronic acid, indocyanine green, and radio-labeled sulphur colloid to assess the function of sinusoidal endothelial cells, hepatocytes, and Kupffer cells, respectively. Measurements were performed immediately after transplantation using syngeneic grafts preserved in University of Wisconsin solution for different periods. Functional recovery was monitored in animals receiving grafts preserved for 24 hr over the first postoperative week.

RESULTS

We found that hepatocyte were less affected compared with the profoundly damaged endothelial cells. The phagocytic ability of Kupffer cells was, however, also seriously compromised, which suggests a selective down-regulation. Functional recovery occurs in a differential manner during the first postoperative week starting with hepatocytes followed by sinusoidal endothelial cells. Phagocytic function further deteriorates after transplantation before showing improvement.

CONCLUSIONS

In viable liver grafts, all cell types recover from preservation/reperfusion injury by the end of the first week after transplantation. The differential time courses of the recovery suggest that successful sinusoidal endothelial cell recovery may depend upon prior hepatocyte regeneration and may involve a paracrine interaction, via cytokines and growth factors.