A. Osama Gaber

A Prospective, Randomized, Double-Blind, Placebo-Controlled Multicenter Trial Comparing Early (7 Day) Corticosteroid Cessation Versus Long-Term, Low-Dose Corticosteroid Therapy

Objective:To compare outcomes with early corticosteroid withdrawal (CSWD) and chronic low dose corticosteroid therapy (CCS). Summary Background Data:Final, 5-year results from the first randomized, double-blind, placebo-controlled trial of early CSWD (at 7 days posttransplant) are presented. Methods:Adult recipients of deceased and living donor kidney transplants without delayed graft function were randomized to receive prednisone (5 mg/d after 6 months posttransplant) or CSWD. Blinding was maintained for 5 years. This clinical trial is registered at www.clinicaltrials.gov (NCT00650468). Results:Results in 386 patients CSWD (n = 191), CCS (n = 195) are presented (CSWD; CCS). No differences were observed at 5 years in the proportion of patients experiencing: primary end point (composite of death, graft loss, or moderate/severe acute rejection) (30/191 (15.7%); 28/195 (14.4%)), patient death (11/191(5.8%);13/195 (6.7%)), death-censored graft loss (11/191 (5.8%); 7/195(3.6%)), biopsy confirmed acute rejection (BCAR) (34/191 (17.8%); 21/195 (10.8%), P = 0.058), moderate/severe acute rejection (15/191 (7.9%); 12/195 (6.2%)). Kaplan Meier analyses of the primary end point and its components also showed no differences; but BCAR was higher with CSWD (P = 0.04). Increased BCAR episodes were primarily corticosteroid-sensitive Banff 1A rejections: the incidence of antibody-treated BCAR was similar between groups (11/191 (5.8%); 13/195 (6.7%)). No differences in renal function were observed at 5 years: mean serum creatinine (1.5 ± 0.6; 1.5 ± 0.7 mg/dL), or Cockroft Gault calculated creatinine clearance (58.6 ± 19.7; 59.8 ± 20.5 mL/min). CSWD was associated with improved serum triglycerides (evaluated by mean and median change from baseline) at all time points (except at 5 years measured by mean change). Weight change also demonstrated changes favoring CSWD (median change from baseline at 5 years: 5.1 vs. 7.7 kg, P = 0.05). New onset diabetes after transplant (NODAT) was similar with respect to proportions who required treatment (23/107 (21.5%)); 18/86 (20.9%); however, fewer CSWD patients required insulin for NODAT at 5 years (4/107 (3.7%)); 10/86 (11.6%), P = 0.049). Changes in HgA1c values (from baseline) were lower in CSWD patients at all time points except 4 years. Conclusions:Early CSWD, compared with CCS, is associated with an increase in BCAR primarily because of mild, Banff 1A, steroid-sensitive rejection, yet provides similar long-term renal allograft survival and function. CSWD provides improvements in cardiovascular risk factors (triglycerides, NODAT requiring insulin, weight gain). Tacrolimus/MMF/antibody induction therapy allows early CSWD with results comparable to long-term low dose (5 mg/d) prednisone therapy.

Amelioration of the physiologic and biochemical changes of acute pancreatitis using an anti-TNF-α polyclonal antibody☆☆☆

Tumor necrosis factor (TNF) is an inflammatory cytokine that may be an important mediator in the development of the systemic sequelae associated with severe acute pancreatitis. The purpose of this study was to determine whether the neutralization of TNF-alpha with a polyclonal antibody could ameliorate selected biochemical parameters of severe pancreatitis in a rat model. Pancreatitis was induced by an antegrade injection of artificial bile into the bile duct. Forty rats were randomized into 4 groups: no surgery (controls), saline infusion to bile duct (sham), placebo treatment in animals with pancreatitis (placebo + Px), and pretreatment with a polyclonal antibody (PAb) in animals with pancreatitis (PAb + Px). Serum TNF-alpha, amylase, calcium, hematocrit, glucose, and ascites volume were measured 2 hours after bile duct infusion. Pretreatment with the PAb produced a significant improvement in all parameters when compared with pancreatitis animals treated with placebo (p < 0.001). In addition, TNF-alpha, which was elevated in animals with pancreatitis, was reduced significantly in treated animals (p < 0.001). These results suggest that TNF-alpha may be an important mediator in the evolution of the systemic manifestations of severe acute pancreatitis.

The Effect of CYP3A5 and MDR1 Polymorphic Expression on Cyclosporine Oral Disposition in Renal Transplant Patients

Variability in CYP3A (CYP3A4/5) and P‐glycoprotein (human MDR1 gene product) activity underlies interindividual differences in oral cyclosporine (CsA) bioavailability. Racial differences in polymorphic expression of CYP3A5 and MDR1 may explain observed interracial variability in oral bioavailability. Our objective was to evaluate the effect of CYP3A5 and MDR1 polymorphic expression on CsA oral disposition. Steady‐state plasma concentration profiles (n = 19) were sampled in renal transplant recipients receiving concentration‐adjusted CsA maintenance therapy. CsA plasma concentrations were measured by fluorescence polarization immunoassay. CYP3A5 and MDR1 genotypes were determined by real‐time polymerase chain reaction. Noncompartmental pharmacokinetic analysis and nonlinear mixed‐effects modeling (NONMEM) were performed to assess the effect of genotype on CsA pharmacokinetics. MDR1 C3435T genotype was identified as the best predictor of CsA systemic exposure. CsA oral clearance was significantly higher in subjects who carried at least one 3435T allele compared to homozygous wild‐type individuals (40.0 ± 2.2 vs. 26.4 ± 3.1 L/h, p = 0.007). MDR1 C3435T genotype accounted for 43% of the interindividual variability of CsA oral clearance in the study population after accounting for interoccasion variability. The authors were unable to independently assess whether CYP3A5 correlated with any CsA pharmacokinetic parameter since all CYP3A5 nonexpressors were also 3435T allele carriers. MDR1 3435T allele carriers have enhanced oral clearance compared to individuals with the CC genotype. The frequency of the 3435T allele is lower in African Americans compared to Caucasians. Thus, the MDR1 C3435T genotype offers a potential mechanistic basis to explain interracial differences in CsA oral bioavailability. Further studies are needed to explore the relationship between CYP3A5 and MDR1 genotype and phenotype.

Anti-TNFα therapy improves survival and ameliorates the pathophysiologic sequelae in acute pancreatitis in the rat

BACKGROUND Elevated levels of tumor necrosis factor-alpha (TNFalpha) have been measured in a lethal model acute pancreatitis (AP) and may contribute to the pathophysiologic sequelae of the disease. METHODS To determine the significance of anti-TNFalpha therapy on survival and disease manifestations in a clinically relevant model of AP, a rat model was developed using a retrograde pancreatic ductal infusion of bile. Animals were randomized to no treatment (n = 30) or treatment with anti-TNFalpha antibody 15 minutes prior to induction of AP (n = 30). Five treated and 5 untreated rats were killed at various time periods up to 72 hours to provide temporal characterization of TNFalpha activity in AP. RESULTS A burst Of TNFalpha activity in the serum of untreated pancreatitis animals between 1 and 3 hours after induction of the disease is prevented by pretreatment with anti-TNFalpha antibody. CONCLUSIONS These findings provide a plausible mechanism for the improvement in biochemical and histologic parameters as well as in overall survival in an experimental model of acute pancreatitis in the rat.

Kidney and pancreas transplantation

Data from the Scientific Registry of Transplant Recipients offer a unique and comprehensive view of US trends in kidney and pancreas waiting list characteristics and outcomes, transplant recipient and donor characteristics, and patient and allograft survival. Important findings from our review of developments during 2002 and the decades transplantation trends appear below.

Effects of tacrolimus on hyperlipidemia after successful renal transplantation: A southeastern organ procurement foundation multicenter clinical study

BACKGROUND Tacrolimus has been shown to have a less adverse effect on the lipid profiles of transplant patients when the drug is started as induction therapy. In order to determine the effect tacrolimus has on lipid profiles in stable cyclosporine-treated renal transplant patients with established hyperlipidemia, a randomized prospective study was undertaken by the Southeastern Organ Procurement Foundation. METHODS Patients of the 13 transplant centers, with cholesterol of 240 mg/dl or greater, who were at least 1 year posttransplant with stable renal function, were randomly assigned to remain on cyclosporine (control) or converted to tacrolimus. Patients converted to tacrolimus were maintained at a level of 5-15 ng/ml, and control patients remained at their previous levels of cyclosporine. Concurrent immunosuppressants were not changed. Levels of total cholesterol, triglycerides, total high-density lipoprotein, low-density lipoprotein (LDL), very-low-density lipoprotein, and apoproteins A and B were monitored before conversion and at months 1, 3, and 6. Renal function and glucose control were evaluated at the beginning and end of the study (month 6). RESULTS A total of 65 patients were enrolled; 12 patients failed to complete the study. None were removed as a result of acute rejection or graft failure. Fifty-three patients were available for analysis (27 in the tacrolimus group and 26 controls). Demographics were not different between groups. In patients converted to tacrolimus treatment, there was a -55 mg/dl (-16%) (P=0.0031) change in cholesterol, a -48 mg/dl (-25%) (P=0.0014) change in LDL cholesterol, and a -36 mg/dl (-23%) (P=0.034) change in apolipoprotein B. There was no change in renal function, glycemic control, or incidence of new onset diabetes mellitus in the tacrolimus group. CONCLUSION Conversion from cyclosporine to tacrolimus can be safely done after successful transplantation. Introduction of tacrolimus to a stable renal patient does not effect renal function or glycemic control. Tacrolimus can lower cholesterol, LDL, and apolipoprotein B. Conversion to tacrolimus from cyclosporine should be considered in the treatment of posttransplant hyperlipidemia.

Effects of Theophylline on Erythropoietin Production in Normal Subjects and in Patients with Erythrocytosis after Renal Transplantation

BACKGROUND Erythrocytosis occurs in 10 to 15 percent of renal-transplant recipients, and there is in vitro evidence that the production of erythropoietin is modulated by adenosine. METHODS We prospectively evaluated the effects of theophylline, a nonselective adenosine antagonist, in eight patients with erythrocytosis after renal transplantation and in five normal controls. RESULTS After an eight-week course of theophylline treatment, the mean (+/- SEM) serum erythropoietin levels were significantly reduced in both the renal-transplant recipients (from 60 +/- 14 units per liter at base line to 9 +/- 7 units after treatment; P less than 0.05) and the normal subjects (from 6.9 +/- 0.8 units per liter at base line to 4.7 +/- 0.5 units per liter after treatment; P less than 0.05). Similarly, the hematocrits were reduced in both the transplant recipients (from 0.58 +/- 0.04 at base line to 0.46 +/- 0.03 after treatment; P less than 0.05) and the normal subjects (from 0.43 +/- 0.01 at base line to 0.39 +/- 0.01; P less than 0.05). In the renal-transplant recipients, red-cell mass was also reduced after eight weeks of theophylline (from 3197 +/- 82 ml at base line to 2273 +/- 69 ml after treatment; P less than 0.05). The previous requirement of weekly phlebotomy was eliminated in all recipients. Plasma and urinary cyclic AMP levels were not increased. These effects were reproducible when the subjects were rechallenged with theophylline after a recovery period. CONCLUSIONS Theophylline attenuates the production of erythropoietin in both normal subjects and patients with erythrocytosis after renal transplantation and may be useful in the treatment of the latter condition.

Donor-specific HLA-DQ antibodies may contribute to poor graft outcome after renal transplantation

Increasing evidence suggests a detrimental effect of donor-specific antibodies directed against the human leukocyte antigen (HLA)-A, -B, and -DR loci on renal allograft outcomes. Limited data exist on the impact of de novo HLA-DQ antibodies. Over a 3-year period, we prospectively monitored 347 renal transplant recipients without pre-transplant donor-specific antibodies for their development de novo. After 26 months of follow-up, 62 patients developed donor-specific antibodies, of which 48 had a HLA-DQ antibody either alone (33 patients) or in combination with an HLA-A, -B, or -DR antibody (15 patients). Only 14 patients developed a donor-specific HLA-A, -B, or -DR antibody without a HLA-DQ antibody present. Acute rejection occurred in 21% of the HLA-DQ-only patients, insignificant when compared with 11% of patients without donor-specific antibodies. At the last follow-up, the mean serum creatinine and the fraction of patients with proteinuria were significantly higher in those that developed only HLA-DQ than those without antibodies. The 3-year graft survival was significantly worse when HLA-DQ antibodies were combined with non-DQ antibodies (52%) compared with HLA-DQ alone, non-DQ antibodies alone, or no antibodies (92-94%). Thus, our prospective monitoring study found that donor-specific HLA-DQ antibodies were the most common type detected and these antibodies may contribute to inferior graft outcomes. Ongoing surveillance is necessary to determine the long-term outcome of patients developing HLA-DQ donor-specific antibodies.

Quantitative detection of T-cell activation markers by real-time PCR in renal transplant rejection and correlation with histopathologic evaluation

Background. The quest for noninvasive methods to diagnose rejection in solid-organ transplants has been rejuvenated by recent observations that specific cytotoxic T-cell markers are up-regulated during rejection. Methods. We developed a one-step real-time polymerase chain reaction (PCR) method allowing reliable detection of the expression of several T-cell genes within a relatively short period of time. The assay is highly sensitive and reproducible with a wide dynamic range allowing accurate quantification of target mRNA in as little as 3 pg total RNA. The utility of this assay in detecting renal allograft rejection was evaluated. Peripheral blood mononuclear cells were collected from 27 patients undergoing kidney allograft biopsies for renal dysfunction after transplantation. Expression of the T-cell activation markers, granzyme B, perforin, and HLA-DRA, was quantified and correlated to the histopathologic changes in the renal biopsies. Results. In cases with allograft rejection (n=8), peripheral lymphocyte expression was increased for granzyme B (P <0.001) and perforin (P <0.08) compared with cases without rejection (n=19). Granzyme B mRNA up-regulation showed the highest specificity for detecting rejection (95%). Moreover, HLA-DRA mRNA was significantly up-regulated (P <0.0016) and had the highest sensitivity (88%) detecting rejection. The up-regulation of both granzyme B and HLA-DRA was most specific in detecting rejection, P <0.001. Conclusions. These data demonstrate that a rapid test of target gene up-regulation using real-time PCR can be used as an aid in the diagnosis of kidney allograft rejection. This is also the first report on the possible utility of HLA-DRA mRNA up-regulation as a marker for kidney transplant rejection.

Predicting poor outcome following hepatectomy: analysis of 2313 hepatectomies in the NSQIP database

BACKGROUND For the past two decades multiple series have documented that liver resection has become safer. The purpose of this study was to determine the current status of hepatic resection in the USA by analysing the multi-institutional experience within the National Surgical Quality Improvement Program (NSQIP) dataset. METHODS Of the 363,897 cases in the 2005-2007 NSQIP Participant Use File, 2313 elective open hepatectomy cases were identified (1344 partial, 230 left, 510 right and 229 extended hepatectomies). A total of 57 perioperative risk factors and 28 postoperative complications were compared. To determine the applicability of NSQIP general risk models to hepatic surgery, the prognostic value of standard multivariate analysis was compared with the NSQIP general surgery aggregate risk indices (expected probability of morbidity [morbprob], expected probability of mortality [mortprob]). RESULTS The median age of patients listed in the database was 60 years; sex distributions were equivalent; 78% were White; 65% of patients had an ASA score of 3 or 4, and the most prevalent co-morbidity was hypertension (46%). A total of 41% of patients had disseminated cancer, 19% of whom had received chemotherapy within 30 days of surgery. The overall 30-day mortality rate was 2.5% (57/2313) and the 30-day major morbidity rate was 19.6% (453/2313). Multivariate analysis identified nine risk factors associated with major morbidity and two risk factors associated with mortality. In contrast, the morbprob and mortprob statistics did not predict outcomes accurately. For those patients who developed major morbidity, the median length of stay was longer (10 vs. 6 days; P = 0.001) and the mortality rate was higher (11.3% vs. 0.3%; P = 0.001). CONCLUSIONS Analysis of the NSQIP experience with hepatectomy indicates that the current mortality and major morbidity rate benchmarks are 2.5% and 19.6%, respectively. Poor outcomes were associated with nutritional status, liver function and the extent of hepatectomy. The NSQIP general surgery morbprob and mortprob values were relatively poor predictors of post-hepatectomy observed morbidity, indicating the need for specialty-specific NSQIP modelling.