L. Paczek

Long-term improvement in renal function with sirolimus after early cyclosporine withdrawal in renal transplant recipients: 2-year results of the Rapamune Maintenance Regimen Study.

Introduction. The purpose of this study was to evaluate early cyclosporine (CsA) withdrawal from a sirolimus (SRL)-CsA-steroid (ST) regimen. Methods. Within 48 hr after transplantation, 525 primary (90%) or secondary (10%) renal allograft recipients with cadaveric (89%) or living (11%) donors received 2 mg of SRL (troughs >5 ng/mL; immunoassay), CsA, and ST. Those eligible (430) were randomly assigned (1:1) at 3 months ± 2 weeks to remain on triple-drug therapy (SRL-CsA-ST group) or to have CsA withdrawn and SRL trough concentrations targeted to 20 to 30 ng/mL (SRL-ST group) until month 12, and 15 to 25 ng/mL thereafter. Results. At 24 months, there were no statistically significant differences in patient survival (94.0% vs. 95.3%), graft survival (91.2% vs. 93.5%), acute rejection after randomization (5.1% vs. 9.8%) or discontinuations (34% vs. 33%) for SRL-CsA-ST versus SRL-ST, respectively. Serum creatinine level was significantly better in patients who had CsA withdrawn (167 vs. 128 &mgr;mol/L, P <0.001), as was the slope of 1/creatinine. Similarly, systolic blood pressure was lower in patients who had CsA withdrawn (141 vs. 134 mm Hg, P <0.001). High-density lipoprotein cholesterol was significantly higher in the SRL-ST group, whereas total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels were not significantly different. Hypertension, creatinine increase, abnormal kidney function, toxic nephropathy, edema, hyperuricemia, cataracts, Herpes zoster, and malignancy were reported significantly more often in patients continuing CsA. Thrombocytopenia, hypokalemia, abnormal liver function tests, abnormal wound healing, ileus, and pneumonia were reported significantly more frequently with SRL-ST. Conclusion. Data at 2 years confirm that early CsA withdrawal followed by an SRL-ST maintenance regimen results in long-term improvement in both renal function and blood pressure, without increased risk of graft loss or late acute rejection.

Machine Perfusion Preservation Improves Renal Allograft Survival

Machine perfusion (MP) has been used as the kidney preservation method in our center for over 10 years. The first, small (n = 74) prospective, single‐blinded randomized study comparing MP and Cold Storage (CS) showed that the incidence of delayed graft function was higher after CS. There have been no reports in the literature on the effect of storage modality on long‐term function of renal allografts. This paper presents an analysis of long‐term results of renal transplantation in 415 patients operated on between 1994 and 1999. Of those, 227 kidneys were MP‐stored prior to KTx. The control group consisted of 188 CS kidney transplants. Kidneys were not randomized to MP or to CS. Donor demographics, medical and biochemical data, cold ischemia time, HLA match and recipient data were collected. Standard triple‐drug immunosuppression was administered to both groups. Mortality, graft survival and incidence of return to hemodialysis treatment were analyzed. Despite longer cold ischemia time and poorer donor hemodynamics in MP group, 5‐year Kaplan‐Meier graft survival was better in MP‐stored than in CS‐stored kidneys (68.2% vs. 54.2%, p = 0.02). Conclusion: In this nonrandomized analysis, kidney storage by MP improved graft survival and reduced the number of patients who returned to dialysis.

The effects of FK778 in combination with tacrolimus and steroids: A phase II Multicenter study in renal transplant patients

Background. In animal and in vitro models, FK778 inhibits acute rejection, modifies vasculopathy, and shows anti-viral activity. We report first efficacy and safety data of FK778 in human kidney transplant recipients at two concentration-controlled ranges. Methods. In a double-blind manner, 149 patients were randomized to a 12-week treatment with FK778 in combination with tacrolimus (Tac) and corticosteroids (S). Of the high-level group (H), 49 patients received 2×600 mg/day FK778 and continued on 150 mg/day, 54 patients of the low-level group (L) got 1×600 mg/day followed by 75 mg/day, and 46 patients received placebo (P). Subsequent FK778 doses were adjusted to trough levels of 100–200 &mgr;g/mL (H) and 10–100 &mgr;g/mL (L). The primary endpoint was the incidence of biopsy proven acute rejection (AR). Results. In 93% of the patients in group L, targeted plasma trough levels were reached by Day 3; in half of the patients in group H, the targeted levels were reached by Day 9. Graft survival at week 16 was 89.7%, 88.8%, and 91.3%, and the incidences of AR were 26.5%, 25.9%, and 39.1% for groups H, L, and P. For the subgroup of patients in which target levels were reached by week 2, incidences were 7.7%, 27.1%, and 39.1%, respectively. Anemia, the most frequently reported adverse event especially in group H, was reversible. Mean total cholesterol and LDL-cholesterol levels were reduced during FK778 treatment compared with group P. Conclusion. FK778 is pharmacologically active, well-tolerated, and safe. To fully benefit from this promising new drug, FK778 dosing will be optimized in subsequent studies.

A prospective randomized multicenter study of tacrolimus in combination with sirolimus in renal-transplant recipients.

Background. Recently, sirolimus (SRL) was introduced as an immunosuppressant in solid-organ transplantation. This study evaluated combinations of SRL and tacrolimus (Tac). Methods. This 6-month study investigated the safety and efficacy of Tac and steroids in combination with three different doses of SRL in renal-transplant recipients. A total of 104 patients were randomized in four groups: one group received Tac and steroids (control n=28), and three groups also received the following daily SRL doses: 0.5 mg (TacSRL0.5, n=25), 1 mg (TacSRL1, n=25), or 2 mg (TacSRL2, n=26). Tac doses were adjusted to whole-blood trough levels. Steroids were tapered from 20 mg per day to 5 mg per day. The SRL groups underwent a second randomization to discontinue SRL at either month 3 or 5. Results. At month 6, patient survival rates were 100%, 100%, 96.0%, and 100%, and graft survival rates were 96.4%, 84.0%, 88.0%, and 84.6%, respectively. The overall safety profile was similar in all groups. The incidences of infections during months 1 to 3 were similar in all groups (control 46.4%, TacSRL0.5 32.0%, TacSRL1 56.0%, TacSRL2 46.2%). The 3-month incidences of hypercholesteremia (cholesterol >240 mg/dL or low-density lipoprotein cholesterol >160 mg/dL) were 21.4%, 36.0%, 48.0%, and 50.0% (P =0.019). Lipid levels improved after withdrawal of SRL. The 3-month incidences of biopsy-proven acute rejection were 28.6% (control), 8.0% (TacSRL0.5), 8.0% (TacSRL1), and 3.8% (TacSRL2) (P =0.014). Conclusion. Tac in combination with low doses of SRL provides a very effective and safe regimen.

Prognostic significance of free radicals: Mediated injury occurring in the kidney donor

Background. Brain death is associated with hemodynamic disturbances in systemic circulation and metabolic storm, and, thus, free radical-mediated injury to donor tissues was hypothesized. An assessment of oxidative stress in the donor and its effect on posttransplant kidney graft function comprised the scope of the study. Methods. A prospective study was performed in 27 donors and 50 kidney transplant recipients. Sera from 27 brain-dead organ donors and preservation media were tested for malondialdehyde (MDA) and for total antioxidant status (TAS). Kidneys were preserved in University of Wisconsin-gluconate solution with machine perfusion. Mean ischemia time was 36.7±8 hours. Organs were transplanted to recipients on the Polish National Waiting List and posttransplant kidney function was monitored periodically. Posttransplant delayed graft function (DF) was diagnosed when a patient required at least one dialysis within first week after transplantation. Acute rejection was diagnosed clinically and confirmed with fine-needle biopsy if necessary. Results. Thirty-two recipients had immediate graft function (IF), and 18 suffered from DF. MDA level in preservation solution at the end of machine perfusion was significantly higher in the DF group (52.6±31 vs. 25.3±19 &mgr;mol/L) whereas donor TAS activity was lower (1.14±0.2 vs. 0.97±0.3 mmol/mL). Patients who suffered from acute rejection received kidneys from donors with significantly higher serum MDA (66±73 &mgr;mol/ml vs. 23±49 for patients without rejection). Serum creatinine 12 to 48 months after transplantation correlated to donor- and preservation-solution MDA (P <0.006). Conclusions. Free-radical mediated injury occurring in the donor and during preservation is strictly correlated with immediate and long-term kidney function. It may also cause grafts to be prone to acute rejection.

Biliary tract complications following liver transplantation

INTRODUCTION Biliary tract complications, which occur in 5.8% to 24.5% of adult liver transplant recipients, remain one of the most common problems following transplantation. The aim of this study was to evaluate these problems and analyze methods of treatment. MATERIAL AND METHODS From 1989 to 2003, 36 (18.7%) among 193 patients who underwent orthotopic liver transplantations in our center developed biliary complications. Biliary strictures that developed in 18 cases (9.3%) were the most common complications. Clinical manifestations of strictures developed at 2 to 24 months after transplantation. Bile leaks occurred in 10 patients (5.2%), and were diagnosed in along the T-tube 4 cases and was not accompanied by any clinical manifestation. Bile leak to the peritoneum after T-tube removal occurred in 2 patients (1.1%). Solitary gallstone formation in one case (0.5%) was removed with the use of ECPW. One patient required retransplantation within 3 months after transplantation, because of the most severe complication-ischemic necrosis of biliary tract. RESULTS Uneventful recovery was achieved in 34 patients in the analyzed group (94.4%). There was no case of recurrence during outpatient follow up. Two patients died in late follow-up of unrelated causes: namely, gastrointestinal bleeding due to a duodenal ulcer and multi-organ failure (MOF) due to a third severe episode of acute liver transplant rejection. CONCLUSIONS Biliary complications remain an important problem in liver transplantation. Endoscopic and radiologic management are effective in the majority of cases. Surgical intervention is obligatory in selected cases.

Urinary tract infections in the early posttransplant period after kidney transplantation: etiologic agents and their susceptibility.

OBJECTIVE Urinary tract infection (UTI) is among the most common infections in solid organ transplantation, especially in kidney transplantation. PATIENTS AND METHODS This study included 295 adult patients undergoing KTx between September 2001 and December 2007. All patients were followed prospectively for UTI during the first 4 weeks after surgery. Samples of urine were investigated by bacteriological cultures to identify microorganisms in accord with standard procedures. Susceptibility testing was performed using Clinical and Laboratory Standards Institute procedures. RESULTS Urine specimens (n=582) were obtained from 84.5% of 245 recipients during the first month after transplantation. Among the isolated bacterial strains (n=291), the most common were Gram-negative bacteria (56.4%) predominantly Serratia marcescens (32.3%) and Enterobacter cloacae (14.6%). Extended- spectrum beta-lactamase (ESBL+) strains were isolated in 52.5% of cases. Gram-positive bacteria comprised 35.7%; most commonly, high-level aminoglycoside resistant (HLAR; 87.8%) and vancomycin-resistant (VRE; 11%) Enterococci. There were fungal strains in 23 cases (7.9%). CONCLUSION Our study showed predominantly Gram-negative rods from the Enterobacteriaceae family comprising (84.8%) of Gram-negative isolates: 52.5% ESBL and resistant enterococci (87.5%) in Gram-positive isolates. The increased proportion of isolates of multi-drug-resistant bacterial agents which can cause severe UTIs may be due to our frequent use of ceftriaxone for perioperative bacterial prophylaxis.

Renal function after liver transplantation: calcineurin inhibitor nephrotoxicity

Renal failure, mainly due to calcineurin inhibitor (CNI) nephrotoxicity, is the most common complication following orthotopic liver transplantation (ltx). The aim of this study was to evaluate the incidence and course of renal failure in adult ltx patients. Severe acute renal failure in early postoperative period due to impaired hemodynamics and CNI nephrotoxicity, occurred in 14 patients, 3 of whom required dialysis. The creatinine clearance after ltx showed a tendency to decrease, but there was no statistically significant difference (P >.05) in the change in serum creatinine clearance levels between patients treated with tacrolimus (TAC) versus Cyclosporine (CsA) during the first 2 years of follow-up. Fourteen patients required conversion of their regimen because of CNI nephrotoxicity namely, dose reduction (n = 7) or discontinuation of CNI therapy with the replacement by mycophenolate mofetil (MMF) (n = 5) or SRL (n = 5). Dose reduction or CNI withdrawal significantly improved the creatinine clearance (P <.05) without affecting lives graft function. No episode of acute rejection was observed after conversion. Neither conversion of CsA to TAC nor the reverse maneuver significantly influenced the serum creatinine level (P >.05). Reduction of the CNI dose or CNI discontinuation or replacement with MMF or SRL in patients with stable liver but impaired renal function is safe, resulting in a significant improvement in renal function.

Trypsin, elastase, plasmin and MMP-9 activity in the serum during the human ageing process

OBJECTIVE the aim of this work was to define the influence of the ageing process on the activity of proteolytic enzymes, such as trypsin, elastase, plasmin and active MMP-9 concentration, as well as the inhibitor alpha 1-antitrypsin. Moreover, we assessed associations between enzyme activity and selected clinical and biochemical parameters. METHODS healthy normotensive volunteers (n = 60, 30 women) aged 20-82 years were split into subgroups: young (aged 20-22), middle-aged (49-52) and elderly (77-82). Serum enzyme activity was assessed using fluorometric methods. RESULTS overall, active MMP-9 concentration and trypsin activity decreased with age, and alpha1-antitrypsin concentration and plasmin activity increased. Activity of elastase increased with age when compared to the young age group. An inverse correlation was identified between MMP-9 concentration and BMI and a direct correlation found between BMI and elastase, plasmin activity and alpha1-antitrypsin concentration. In the middle-aged group, glucose correlated directly with trypsin activity and inversely with MMP-9 concentration. Trypsin activity and MMP-9 concentration correlated inversely with cholesterol concentration and plasmin and elastase activity, and the alpha1-antitrypsin concentration correlated with cholesterol concentration in the overall group. CONCLUSIONS the results confirm the influence of the ageing process on the activity of serum proteolytic enzymes. The activity of individual proteolytic enzymes in the serum changes with age.

Urine proteome of autosomal dominant polycystic kidney disease patients.

BackgroundAutosomal dominant polycystic kidney disease (ADPKD) is responsible for 10% of cases of the end stage renal disease. Early diagnosis, especially of potential fast progressors would be of benefit for efficient planning of therapy. Urine excreted proteome has become a promising field of the search for marker patterns of renal diseases including ADPKD. Up to now however, only the low molecular weight fraction of ADPKD proteomic fingerprint was studied. The aim of our study was to characterize the higher molecular weight fraction of urinary proteome of ADPKD population in comparison to healthy controls as a part of a general effort aiming at exhaustive characterization of human urine proteome in health and disease, preceding establishment of clinically useful disease marker panel.ResultsWe have analyzed the protein composition of urine retentate (>10 kDa cutoff) from 30 ADPKD patients and an appropriate healthy control group by means of a gel-free relative quantitation of a set of more than 1400 proteins. We have identified an ADPKD-characteristic footprint of 155 proteins significantly up- or downrepresented in the urine of ADPKD patients. We have found changes in proteins of complement system, apolipoproteins, serpins, several growth factors in addition to known collagens and extracellular matrix components. For a subset of these proteins we have confirmed the results using an alternative analytical technique.ConclusionsObtained results provide basis for further characterization of pathomechanism underlying the observed differences and establishing the proteomic prognostic marker panel.