A Novel, Dose-Adjusted Tacrolimus Trough-Concentration Model for Predicting and Estimating Variance After Kidney Transplantation.

BACKGROUND AND OBJECTIVE: Given that a high intrapatient variability (IPV) of tacrolimus whole blood concentration increases the risk for a poor kidney transplant outcome, some experts advocate routine IPV monitoring for detection of high-risk patients. However, attempts to estimate the variance of tacrolimus trough concentrations (TTC) are limited by the need for patients to receive a fixed dose over time and/or the use of linear statistical models. A goal of this study is to overcome the current limitations through the novel application of statistical methodology generalizing the relationship between TTC and dose through the use of nonparametric functional regression modeling. METHODS: With TTC as a response and dose as a covariate, the model employs an unknown bivariate function, allowing for the potentially complex, nonlinear relationship between the two parameters. A dose-adjusted variance of TTC is then derived based on standard functional principal component analysis (FPCA). To assess the model, it was compared against an FPCA-based model and linear mixed-effects models using prediction error, bias, and coverage probabilities for simulated data as well as phase III data from the Astellas new drug application studies for extended-release tacrolimus. RESULTS: Our numerical investigation indicates that the new model better predicts dose-adjusted TTCs compared with the prediction of linear mixed effects models. Estimated coverage probabilities also indicate that the new model accurately accounts for the variance of TTC during the periods of large fluctuation in dose, whereas the linear mixed effects model consistently underestimates the coverage probabilities because of the inaccurate characterization of TTC fluctuation. CONCLUSION: This is the first known application of a functional regression model to assess complex relationships between TTC and dose in a real clinical setting. This new method has applicability in future clinical trials including real-world data sets due to flexibility of the nonparametric modeling approach.

Real-World Study of Once-Daily, Extended-Release Tacrolimus Versus Twice-Daily, Immediate-Release Tacrolimus in Kidney Transplantation: Clinical Outcomes and Healthcare Resource Utilization.

INTRODUCTION: Real-world data with extended-release tacrolimus (ER-T) are lacking in the USA. This study examined clinical outcomes and healthcare resource utilization in kidney transplant patients receiving ER-T in clinical practice. METHODS: This was a retrospective, single-center analysis (February-June 2016) using data from Northwestern University's Enterprise Data Warehouse. Adult patients receiving a kidney transplant in the preceding 4 years, treated de novo or converted to ER-T from immediate-release tacrolimus (IR-T) within 10 days post-transplantation, and maintained on ER-T (at least 3 months) were included. Patients were matched for demographic and clinical characteristics with IR-T-treated control patients. Endpoints included clinical outcomes and healthcare resource utilization up to 1 year post-transplantation. RESULTS: A total of 19 ER-T-treated patients were matched with 55 IR-T-treated patients. No ER-T-treated patients experienced biopsy-confirmed acute rejection (BCAR) or graft failure versus 3 (5.5%) and 3 (5.5%) IR-T-treated patients, respectively. Mean estimated glomerular filtration rate (eGFR), the number of all-cause outpatient visits, readmissions, and all-cause hospitalization days were comparable between groups. Tacrolimus trough levels, days to target level (6-10 ng/mL), and number of required dose adjustments were also similar. CONCLUSION: Real-world clinical outcomes and healthcare resource utilization were similar with ER-T and IR-T. Larger studies will need to investigate the trend toward fewer BCAR events, and increased graft survival with ER-T. FUNDING: Astellas Pharma Global Development, Inc. Plain language summary available for this article.

The Association of Tacrolimus Formulation Switching with Trough Concentration Variability: A Retrospective Cohort Study of Tacrolimus Use Post-Kidney Transplantation Based on National Drug Code (NDC) Numbers.

INTRODUCTION: It was hypothesized that patients experiencing at least one tacrolimus formulation switch may require more frequent therapeutic drug monitoring, subsequent dose adjustments, and a potential for untoward clinical outcomes than patients who remain on a single formulation. METHODS: Eligible patients were adult kidney transplant recipients with stable renal function at month 3 post-transplant and no evidence of acute rejection, receiving an oral, tacrolimus-based regimen. Patients were categorized into two groups (fixed or variable formulation) using the US National Drug Code (NDC) on the basis of tacrolimus formulation usage over the 12-month period. RESULTS: A total of 305 patients were enrolled from four US transplant centers; 44 (14.4%) received multiple formulations and 261 (85.6%) received a single formulation. Mean number of tacrolimus dose adjustments and mean cumulative milligram dose change were not statistically different between the two groups. Mean trough-to-dose ratio, frequency of trough level measurements, and mean number of excursions above 120% or below 80% of the patient's mean trough concentration were significantly higher in the variable compared to the fixed formulation group. CONCLUSION: A variable tacrolimus formulation regimen was associated with a higher frequency of trough level measurements and a greater number of excursions in trough levels compared with continuing on a fixed formulation regimen of tacrolimus in this retrospective chart review study. FUNDING: Astellas Pharma Global Development, Inc. Plain language summary available for this article.

Comparison of the effects of standard vs low-dose prolonged-release tacrolimus with or without ACEi/ARB on the histology and function of renal allografts.

Targeting the renin-angiotensin system and optimizing tacrolimus exposure are both postulated to improve outcomes in renal transplant recipients (RTRs) by preventing interstitial fibrosis/tubular atrophy (IF/TA). In this multicenter, prospective, open-label controlled trial, adult de novo RTRs were randomized in a 2 × 2 design to low- vs standard-dose (LOW vs STD) prolonged-release tacrolimus and to angiotensin-converting enzyme inhibitors/angiotensin II receptor 1 blockers (ACEi/ARBs) vs other antihypertensive therapy (OAHT). There were 2 coprimary endpoints: the prevalence of IF/TA at month 6 and at month 24. IF/TA prevalence was similar for LOW vs STD tacrolimus at month 6 (36.8% vs 39.5%; P = .80) and ACEi/ARBs vs OAHT at month 24 (54.8% vs 58.2%; P = .33). IF/TA progression decreased significantly with LOW vs STD tacrolimus at month 24 (mean [SD] change, +0.42 [1.477] vs +1.10 [1.577]; P = .0039). Across the 4 treatment groups, LOW + ACEi/ARB patients exhibited the lowest mean IF/TA change and, compared with LOW + OAHT patients, experienced significantly delayed time to first T cell-mediated rejection. Renal function was stable from month 1 to month 24 in all treatment groups. No unexpected safety findings were detected. Coupled with LOW tacrolimus dosing, ACEi/ARBs appear to reduce IF/TA progression and delay rejection relative to reduced tacrolimus exposure without renin-angiotensin system blockade. ClinicalTrials.gov identifier: NCT00933231.

Amelioration of hepatic inflammation in a mouse model of NASH using a dithiocarbamate derivative.

PURPOSE: The process whereby liver inflammation develops in non-alcoholic steatohepatitis (NASH) is not fully understood. While modification of the inflammatory milieu is an attractive target to prevent the development of hepatocellular injury, most antiinflammatory agents have proven ineffective in this setting. Tetraethylthiuram disulfide (TDSF) is able to induce S-glutathionylation of NF-κB along with critical signaling proteins involved with inflammation, especially when complexed with a heavy metal. For this reason, we hypothesized that administration of TDSF would function to ameliorate necroinflammatory activity in a mouse model of NASH. METHODS: Mice were divided into five groups and received control chow versus a methionine-choline-deficient diet. After 6 weeks of TDSF versus sham gavage, animals were necropsied. Using conventional H&E staining, livers were examined using the Brunt scoring system by a hepatopathologist blinded to treatment groups. Validated mouse primer sets were used for quantitative real-time PCR to evaluate changes in mRNA expression. RESULTS: Livers treated with TDSF demonstrated a qualitative reduction in lobular inflammation, lipogranuloma formation, and Kupffer cell accumulation, but not steatosis. Significant reductions in inflammatory transcripts for α-1-collagen, TGF-ß, Mmp2, MCP-1, and TNF-1α were also observed. CONCLUSIONS: Animals treated with TDSF exhibit a reduction in lobular inflammation that is independent of lipid accumulation when administered MCD diet. Similar reductions are seen in several inflammatory transcripts associated with NASH. Additional work in this area may reveal a therapeutic role for TDSF or similar agents in curtailing inflammatory signaling within the liver.

Perceived benefits of a transplant surgery experience to general surgery residency training.

OBJECTIVES: The benefit of a solid-organ transplant experience during general surgical training has been questioned recently. In 2008, in response to an American Board of Surgery (ABS) directive, a survey was conducted by the Association of Program Directors in Surgery (APDS) in coordination with the American Society of Transplant Surgeons (ASTS) to determine the perceived value of a transplant surgery rotation to program directors and residents. With the aim of providing additional insight, we conducted a separate study, independent of the ABS and ASTS, to ascertain resident perceptions regarding the specific skill sets that they acquire during their transplant surgery rotations and their applicability to other surgical subspecialties. METHODS: A preliminary, 51-item, web-based questionnaire was completed by 69.6% of residents in nationally accredited general surgery programs who accessed the survey. The results were examined using appropriate statistical methods to determine associations between answers. RESULTS: Although only 16.6% of participants responded that they were considering a career in transplantation, 63.4% answered that the skill sets acquired during this rotation would assist them in their surgical careers regardless of their chosen specialty. Most (65.5%) respondents answered that the techniques learned were directly applicable to other specialties, such as vascular, urologic, trauma, and hepatobiliary surgery. Free response questions indicated that the most common criticisms of this rotation were the limited amount of operative participation, lack of teaching by attendings, and lifestyle limitations. CONCLUSIONS: The results of this study indicate that surgery residents are conflicted regarding their transplant surgery experience but regard it as a beneficial addition to their training. Most respondents indicated also that these skills were transferable directly to other surgical specialties.

Efficacy of neoadjuvant chemoradiation, followed by liver transplantation, for perihilar cholangiocarcinoma at 12 US centers.

BACKGROUND & AIMS: Excellent single-center outcomes of neoadjuvant chemoradiation and liver transplantation for unresectable perihilar cholangiocarcinoma caused the United Network of Organ Sharing to offer a standardized model of end-stage liver disease (MELD) exception for this disease. We analyzed data from multiple centers to determine the effectiveness of this treatment and the appropriateness of the MELD exception. METHODS: We collected and analyzed data from 12 large-volume transplant centers in the United States. These centers met the inclusion criteria of treating 3 or more patients with perihilar cholangiocarcinoma using neoadjuvant therapy, followed by liver transplantation, from 1993 to 2010 (n = 287 total patients). Center-specific protocols and medical charts were reviewed on-site. RESULTS: The patients completed external radiation (99%), brachytherapy (75%), radiosensitizing therapy (98%), and/or maintenance chemotherapy (65%). Seventy-one patients dropped out before liver transplantation (rate, 11.5% in 3 months). Intent-to-treat survival rates were 68% and 53%, 2 and 5 years after therapy, respectively; post-transplant, recurrence-free survival rates were 78% and 65%, respectively. Patients outside the United Network of Organ Sharing criteria (those with tumor mass >3 cm, transperitoneal tumor biopsy, or metastatic disease) or with a prior malignancy had significantly shorter survival times (P < .001). There were no differences in outcomes among patients based on differences in surgical staging or brachytherapy. Although most patients came from 1 center (n = 193), the other 11 centers had similar survival times after therapy. CONCLUSIONS: Patients with perihilar cholangiocarcinoma who were treated with neoadjuvant therapy followed up by liver transplantation at 12 US centers had a 65% rate of recurrence-free survival after 5 years, showing this therapy to be highly effective. An 11.5% drop-out rate after 3.5 months of therapy indicates the appropriateness of the MELD exception. Rigorous selection is important for the continued success of this treatment.

Liver transplantation in septuagenarians receiving model for end-stage liver disease exception points for hepatocellular carcinoma: the national experience.

Current liver allocation policy in the United States grants liver transplant candidates with stage T2 hepatocellular carcinoma (HCC) a priority Model for End-Stage Liver Disease (MELD) score of 22, regardless of age. Because advanced age may portend an increase in all-cause mortality after transplantation for any diagnosis, the aim of this study was to examine overall posttransplant survival in elderly patients with HCC versus younger cohorts. Based on Organ Procurement and Transplantation Network data, Kaplan-Meier 5-year survival rates were compared. Recipients undergoing primary liver transplantation were stratified into cohorts based on age (<70 or ≥ 70 years) and the receipt of MELD exception points for HCC. Log-rank and Wilcoxon tests were used for statistical comparisons. In 2009, 143 transplants were performed for patients who were 70 years old or older. Forty-two percent of these patients received a MELD exception for HCC. Regardless of the diagnosis, the overall survival rate was significantly attenuated for the septuagenarians versus the younger cohort. After 5 years of follow-up, this disparity exceeded 10% to 15% depending on the populations being compared. The 1-, 2-, 3-, 4-, and 5-year actuarial survival rates were 88.4%, 83.2%, 79.6%, 76.1%, and 72.7%, respectively, for the patients who were younger than 70 years and 81.1%, 73.8%, 67.1%, 61.9%, and 55.2%, respectively, for the patients who were 70 years old or older. Five-year survival was negatively affected for patients with HCC who were younger than 70 years; this disparity was not observed for patients with HCC who were 70 years old or older. In conclusion, although patients who are 70 years old or older compose a small fraction of transplant recipients in the United States, patients in this group undergoing transplantation for HCC form an even smaller subset. Overall, transplantation in this age group yields outcomes inferior to those for younger cohorts. However, unlike patients who are less than 70 years old and receive MELD exception points, overall liver transplant survival is not affected by HCC at an advanced age.

Recurrent hepatocellular carcinoma in liver transplant recipients with hepatitis C.

PURPOSE: Hepatitis C (HCV) is the most common liver disease in patients transplanted with hepatocellular carcinoma (HCC) in the West. We examined predictors of HCC recurrence in liver transplant recipients with HCV. METHODS: From 1997 to 2006, 53 patients with HCC and HCV underwent liver transplantation. Pre-and post-operative data (including liver biopsies 4 months post-transplant) were collected. Differences between HCC recurrence and non-recurrence groups were detected by Student's t test or chi-square test. Data were analyzed as predictors of HCC recurrence by logistic regression multivariate analysis. Cumulative survival was analyzed by Kaplan-Meier curves and compared by the log-rank test. RESULTS: Eleven of 53 patients (20.8%) developed HCC recurrence at a median interval of 15 months (2 to 55 months). Median Histology Activity Index (HAI) of liver biopsies, AST, and ALT at 4 months were significantly greater in patients with HCC recurrence. Independent predictors of HCC recurrence were HAI ≥ 4 at 4 months, ALT ≥ 100 at 4 months, and vascular invasion. Patients with HCC recurrence had significantly decreased survival. CONCLUSIONS: In this preliminary study, Histology Activity Index and ALT at 4 months, as well as vascular invasion, predicted HCC recurrence in liver transplant recipients with HCV.

Impact of calcineurin inhibitors on hepatitis C recurrence after liver transplantation.

BACKGROUND AND AIMS: The aim of this retrospective study is to assess the impact of calcineurin inhibitors on hepatitis C virus recurrence following liver transplantation. METHODS: A total of 396 patients underwent liver transplantation for hepatitis C virus-induced liver disease between 1991 and 2005 at a single center. We examined the pre- and post-operative characteristics of patients who received either cyclosporine (n = 126) or tacrolimus (n = 270) as maintenance immunosuppression. In addition, we compared the postoperative course, including patient, graft and hepatitis C virus recurrence-free survival between the two groups. RESULTS: There were no significant differences between the two groups in either post-operative hepatitis C virus-ribonucleic acid or histological fibrosis score (performed within 6 months after transplant per protocol). The graft and patient survivals did not differ between the two groups (logrank p = 0.34 and 0.15, respectively). Histologic hepatitis C virus recurrence-free survival, however, was significantly higher in the cyclosporine group than in the tacrolimus group (55.4 vs. 30.8% at 1 year, 18.6 vs. 10.3% at 3 years, 16.7 vs. 8.1% at 5 years, p < 0.001). CONCLUSIONS: Patients transplanted for hepatitis C virus and treated with cyclosporine versus tacrolimus may have a higher recurrence-free survival.

Using the modern Silverhawk™ atherectomy catheter to characterize biliary structures that appear malignant: review of initial experience.

BACKGROUND: Diagnosis of a biliary stricture often hinges on cytological interpretation. In the absence of accompanying stroma, these results can often be equivocal. In theory, advanced shave biopsy techniques would allow for the preservation of tissue architecture and a more accurate definition of biliary pathology. OBJECTIVES: We sought to determine the initial diagnostic utility of the modern Silverhawk™ atherectomy (SA) catheter in the evaluation of biliary strictures that appear to be malignant. METHODS: A total of 141 patients with biliary pathology were identified during a retrospective review of medical records for the years 2006-2011. The SA catheter was employed 12 times in seven patients for whom a tissue diagnosis was otherwise lacking. RESULTS: Neoplasia was definitively excluded in seven specimens from four patients. These four individuals were followed for 1-5 years to exclude the development of cholangiocarcinoma (CC). Samples were positive for CC in three patients, one of whom became eligible for neoadjuvant therapy and orthotopic liver transplantation. CONCLUSIONS: The SA catheter appears to be a useful adjunct in diagnosing patients with biliary pathology. The existence of this technique, predicated on tissue architecture, may impact therapy, allow more timely diagnosis, and exclude cases of equivocal cytology. Although the initial results of SA use are promising, more experience is required to effectively determine its clinical accuracy.

Liver transplantation in a 7-month-old girl with Caroli's disease.

Caroli's disease (including Caroli's syndrome) is a rare autosomal recessive disorder of the liver characterized by diffuse cystic dilatation of the intrahepatic bile ducts. The disease may present at any age and is characterized by recurrent episodes of biliary obstruction, cholangitis, hepaticolithiasis, and liver abscesses. Caroli's syndrome is further associated with congenital hepatic fibrosis and portal hypertension. Patients with recurrent complications or cirrhosis may die because of recurrent infection, portal hypertension, liver failure, or cholangiocarcinoma. Liver transplantation is the treatment of choice for these complicated patients. Here we describe the youngest reported patient with Caroli's syndrome treated successfully using liver transplantation and review the recent literature.

Adult post-transplant lymphoproliferative disease in the liver graft in patients with recurrent hepatitis C.

AIM: The aim of this study is to clarify the association between hepatitis C virus (HCV) infection and post-transplant lymphoproliferative disease (PTLD) in the liver allograft. METHODS: Of the 933 adults who underwent liver transplantation (LT) between 1990 and 2005, 10 patients developed PTLD. Seven of the 10 patients that were HCV(+) (group 1) were compared with three HCV-negative recipients (group 2). RESULTS: The mean time between LT and PTLD was 24.5 months. There were no differences between in Epstein-Barr virus antibody status or tumor lymphocyte subsets. In five of the seven HCV-positive recipients who developed PTLD, PTLD recurred preferentially in the liver allograft, whereas none of the three HCV-negative patients who developed PTLD did so in the liver (71.4 vs. 0%, respectively, P=0.038). In all five patients with graft PTLD, HCV recurred within 12 months followed by PTLD. There were significant differences between groups 1 and 2 in mean lymphocyte infiltrate scores (6.0±2.1 vs. 2.0±0.7, P=0.037), fibrosis stage (2.4±0.5 vs. 0.7±0.5, P=0.029), and frequency of lymphoid follicles in portal areas (33.6±14.8% vs. 1.1±2.3%, P=0.0002). CONCLUSION: When PTLD occurs in patients with HCV recurrence after LT, it does so preferentially in the liver allograft.

ENCODE tiling array analysis identifies differentially expressed annotated and novel 5' capped RNAs in hepatitis C infected liver.

Microarray studies of chronic hepatitis C infection have provided valuable information regarding the host response to viral infection. However, recent studies of the human transcriptome indicate pervasive transcription in previously unannotated regions of the genome and that many RNA transcripts have short or lack 3' poly(A) ends. We hypothesized that using ENCODE tiling arrays (1% of the genome) in combination with affinity purifying Pol II RNAs by their unique 5' m7GpppN cap would identify previously undescribed annotated and unannotated genes that are differentially expressed in liver during hepatitis C virus (HCV) infection. Both 5'-capped and poly(A)+ populations of RNA were analyzed using ENCODE tiling arrays. Sixty-four annotated genes were significantly increased in HCV cirrhotic as compared to control liver; twenty-seven (42%) of these genes were identified only by analyzing 5' capped RNA. Thirty-one annotated genes were significantly decreased; sixteen (50%) of these were identified only by analyzing 5' capped RNA. Bioinformatic analysis showed that capped RNA produced more consistent results, provided a more extensive expression profile of intronic regions and identified upregulated Pol II transcriptionally active regions in unannotated areas of the genome in HCV cirrhotic liver. Two of these regions were verified by PCR and RACE analysis. qPCR analysis of liver biopsy specimens demonstrated that these unannotated transcripts, as well as IRF1, TRIM22 and MET, were also upregulated in hepatitis C with mild inflammation and no fibrosis. The analysis of 5' capped RNA in combination with ENCODE tiling arrays provides additional gene expression information and identifies novel upregulated Pol II transcripts not previously described in HCV infected liver. This approach, particularly when combined with new RNA sequencing technologies, should also be useful in further defining Pol II transcripts differentially regulated in specific disease states and in studying RNAs regulated by changes in pre-mRNA splicing or 3' polyadenylation status.

Plasmapheresis and Intravenous Immune Globulin Improve Neurologic Outcome of Central Pontine Myelinolysis Occurring Post Orthotopic Liver Transplant.

OBJECTIVE: To report 2 cases of central pontine myelinolysis (CPM) post liver transplantation in which treatment with plasmapheresis and intravenous immune globulin improved expected neurologic outcome. CASE SUMMARY: Two patients who underwent orthotopic liver transplant developed CPM early in their postoperative course. Magnetic resonance imaging of the brain demonstrated severe demyelination of either the pons or the midbrain, respectively. Both patients developed significant neurologic abnormalities, including acute mental status changes, severe muscle weakness, spasticity, and/or prolonged paralysis. Pretransplant laboratory results indicated serum sodium levels fluctuating between 115 mEq/L and 152 mEq/L. Both patients received 6 days of plasmapheresis (PP) followed by 5 consecutive days of intravenous immune globulin (IVIG). Significant neurologic improvement was experienced at 2 and 4 weeks, respectively, after therapy was initiated. Complete resolution of neurologic symptoms was evident at 1 year follow-up. DISCUSSION: Currently, specific guidelines or recommendations for the treatment of CPM are practically nonexistent. CPM remains a neurologic complication that is difficult to treat and may result in permanent significant neurologic sequelae. The etiology and pathogenesis of this disease are unclear, although aggressive osmolar correction, particularly in the setting of hyponatremia, is the main risk factor. While patients may eventually show some improvement with supportive care, progress is often protracted, and complete resolution of symptoms is exceedingly rare. The severity of the midbrain lesions juxtaposed against the rapidity of symptom resolution in these 2 patients alludes to a potential therapeutic benefit after initiation of therapy with PP and IVIG. CONCLUSIONS: These cases suggest that prompt recognition of CPM and initiation of PP and IVIG may help modulate its progress and improve long-term neurologic outcome.

Liver transplantation for cholangiocarcinoma.

Liver transplantation for cholangiocarcinoma (CCA) remains a controversial subject. More than 15 years after, a novel protocol combining neoadjuvant chemoradiation and orthotopic liver transplantation was first used in patients with unresectable hilar CCAs, these methods have yet to reach broad application. Results have confirmed that this approach leads to significantly lower recurrence rates and higher long-term survival rates than other existing treatment modalities. Despite this, protocols to treat patients with CCA are not widespread, and are available at only a handful of transplant programs. At these centers, treatment success may ultimately hinge on regional model for end-stage liver disease scores and waiting time for transplant. While acknowledging these factors as well as a severe organ shortage, it is important that the transplant community not overlook a potentially effective form of therapy for a previously untreatable disease.

Binding of anti-HLA class I antibody to endothelial cells produce an inflammatory cytokine secretory pattern.

Current methods are inadequate for the diagnosis of early chronic allograft rejection. The goal of this study was to determine whether ligation of anti-HLA antibodies to endothelial cells is associated with a distinctive cytokine secretory pattern. Human iliac artery endothelial cells (HIAEC) cultured in vitro were incubated with w6/32, an anti-HLA class I mAb. Culture supernatants collected daily for up to 4 days were tested for secretion of 13 cytokines using a multiplexed fluorescent microsphere immunoassay. Culture of HIAEC with medium containing mAb w6/32 supported the growth of HIAEC during the 4-day study period. Levels of the pro-inflammatory cytokines IL-1beta, IL-6, IL-8, and TNF-alpha became significantly increased in supernatants of HIAEC incubated with the mAb w6/32. We conclude that ligation of anti-HLA class I antibodies to HLA class I antigens in endothelial cells initiates an acute inflammatory process and detecting an inflammatory cytokine secretory pattern might be useful to diagnose sub-clinical chronic allograft rejection.

Decreased incidence of acute rejection in adolescent kidney transplant recipients using antithymocyte induction and triple immunosuppression.

BACKGROUND: Acute rejection is a frequent event in pediatric renal transplantation; it can diminish allograft function and affect long-term outcome. Recent data from the North American Pediatric Renal Transplant Cooperative Study indicates that the rate of acute rejection remains high despite current immunosuppressive regimens. METHODS: In this retrospective series, we examined 37 pediatric renal transplant recipients who received induction doses of antithymocyte globulin combined with maintenance immunotherapy using tacrolimus, mycophenolate mofetil, and prednisone. The postoperative course was reviewed for initial and total hospital stay, number of rehospitalizations, evidence of posttransplant complications, graft fibrosis, and overall patient and graft survival. RESULTS: Three episodes of acute rejection (8.1%) were recorded in the first year posttransplant. The median initial hospital stay for patients receiving a kidney transplant was 8 days. Patient and graft survival were 100% and 91.9% at 1 year, respectively. The incidence of viral infection (cytomegalovirus, BK virus, and Epstein-Barr virus) and posttransplant lymphoproliferative disease remained low. Urinary tract infection and fluid and electrolyte complications were the main causes of posttransplant hospitalization. CONCLUSIONS: We conclude that induction with antithymocyte globulin and maintenance immunosuppression with tacrolimus, mycophenolate, and prednisone should be considered a valuable tool in the management of children undergoing renal transplantation.

Recombinant plasma gelsolin infusion attenuates burn-induced pulmonary microvascular dysfunction.

Reduced plasma concentrations of the extracellular actin-binding proteins gelsolin and Gc-globulin correlate with pulmonary failure and death in humans after injury. The purpose of this study was to investigate the role of plasma gelsolin in the pathophysiology of inflammation-induced lung injury. We postulated that plasma gelsolin levels decrease at an early time point after burn injury and that the intravenous infusion of gelsolin prevents burn-induced pulmonary microvascular dysfunction. Adult Sprague-Dawley rats were randomized to undergo a 40% body surface area thermal injury (Burn) or manipulation without burn (Sham). Plasma gelsolin and Gc-globulin concentrations were determined at various times during the first 6 days of injury by Western blotting. Other animals were randomized to receive either recombinant human gelsolin (0.078, 0.78, or 7.8 mg) or albumin (7.8 mg) before and 8 h after Burn or Sham. Twenty-four hours later, pulmonary microvascular permeability was assessed by measuring the capillary filtration by use of an isolated, perfused lung model. We found that plasma gelsolin levels of burn-injured rats decreased to 10% of normal levels within 12 h and remained below normal levels for up to 6 days postinjury. Gc-globulin values also fall, but to a lesser extent and only transiently. Treatment of burned animals with intravenous infusions of recombinant human gelsolin prevented the increase in pulmonary microvascular permeability that accompanies this injury. Our findings are consistent with the hypothesis that plasma gelsolin depletion contributes to the pathophysiology of pulmonary microvascular dysfunction during inflammation.