Light Chain Podocytopathy Mimicking Recurrent Focal Segmental Glomerulosclerosis.

Kidney injury related to paraproteinemia is common and typically occurs after the fourth decade of life in association with an underlying plasma cell dyscrasia or other lymphoproliferative disease. Kidney transplantation in paraprotein-related kidney disease can be successful in conjunction with treatment of the underlying hematopoietic process; however, when hematologic response to therapy is not achieved, recurrent kidney injury is frequently seen. We describe a young male patient who presented at the age of 23 years with end-stage kidney disease thought to be secondary to focal segmental glomerulosclerosis; this patient ultimately received two kidney allografts. He experienced recurrent proteinuria in both kidneys, with a biopsy from his second allograft showing kappa-restricted crystalline light chain podocytopathy, which was identified in both his native and first allograft kidneys upon retrospective review. Recurrent light chain podocytopathy has not been previously reported but poses a diagnostic challenge as it can mimic focal segmental glomerulosclerosis, particularly in young patients in whom paraprotein-related kidney injury is usually not suspected.

Association of Clinical Events With Everolimus Exposure in Kidney Transplant Patients Receiving Low Doses of Tacrolimus.

A key objective in the use of immunosuppression after kidney transplantation is to attain the optimal balance between efficacy and safety. In a phase 3b, multicenter, randomized, open-label, noninferiority study, the incidences of clinical events, renal dysfunction, and adverse events (AEs) were analyzed at 12 months in 309 de novo renal transplant recipients receiving everolimus (EVR), low-dose tacrolimus (LTac), and prednisone. Cox proportional hazard regression modeling was used to estimate the probability of clinical events at specified combinations of time-normalized EVR and Tac trough concentrations. At 12 months, the highest incidence of treated biopsy-proven acute rejection (tBPAR) and graft loss occurred most often in patients with EVR trough concentration <3 ng/mL (64.7% and 10.5%, respectively). At 1 month and 12 months, increasing EVR levels were associated with fewer tBPAR events (both p < 0.0001). Low estimated glomerular filtration rate (eGFR) and decreased eGFR occurred more often in patients with lower EVR and higher Tac levels. AEs were most often observed in patients with EVR levels <3 ng/mL. This study supports maintaining an EVR trough concentration of 3-8 ng/mL, when combined with LTac, to achieve balanced efficacy and safety in renal transplant recipients. TRIAL REGISTRATION: NCT01025817.

Efficacy and Safety of Everolimus Plus Low-Dose Tacrolimus Versus Mycophenolate Mofetil Plus Standard-Dose Tacrolimus in De Novo Renal Transplant Recipients: 12-Month Data.

In this 12-month, multicenter, randomized, open-label, noninferiority study, de novo renal transplant recipients (RTxRs) were randomized (1:1) to receive everolimus plus low-dose tacrolimus (EVR+LTac) or mycophenolate mofetil plus standard-dose Tac (MMF+STac) with induction therapy (basiliximab or rabbit anti-thymocyte globulin). Noninferiority of composite efficacy failure rate (treated biopsy-proven acute rejection [tBPAR]/graft loss/death/loss to follow-up) in EVR+LTac versus MMF+STac was missed by 1.4%, considering the noninferiority margin of 10% (24.6% vs. 20.4%; 4.2% [-3.0, 11.4]). Incidence of tBPAR (19.1% vs. 11.2%; p < 0.05) was significantly higher, while graft loss (1.3% vs. 3.9%; p < 0.05) and composite of graft loss/death/lost to follow-up (6.1% vs. 10.5%, p = 0.05) were significantly lower in EVR+LTac versus MMF+STac groups, respectively. Mean estimated glomerular filtration rate was similar between EVR+LTac and MMF+STac groups (63.1 [22.0] vs. 63.1 [19.5] mL/min/1.73 m2 ) and safety was comparable. In conclusion, EVR+LTac missed noninferiority versus MMF+STac based on the 10% noninferiority margin. Further studies evaluating optimal immunosuppression for improved efficacy will guide appropriate dosing and target levels of EVR and LTac in RTxRs.

New-Onset Diabetes After Transplantation: Results From a Double-Blind Early Corticosteroid Withdrawal Trial.

New-onset diabetes after transplantation (NODAT) is an important complication following kidney transplantation. Data from the 5-year early steroid withdrawal double-blind randomized trial were analyzed to determine if steroid avoidance reduced the NODAT risk. Incidence, timing and risk factors for NODAT were evaluated using eight definitions. By American Diabetes Association definition, 36.3% of patients on chronic corticosteroids (CCS) and 35.9% on early corticosteroid withdrawal (CSWD) were diagnosed with NODAT by 5 years. The definition combining fasting blood glucose ≥126 mg/dL on two occasions or treatment identified slightly more cases of NODAT: CCS (39.3%) and CSWD (39.4%). Through 5 years posttransplant, the proportion of NODAT patients requiring treatment were similar (CSWD 22.5% vs. CCS 21.5%); however, insulin therapy was lower with CSWD (3.7% vs. 11.6%; p = 0.049). By multivariate analysis, only age, but not corticosteroid use, was a significant risk factor for NODAT for more than one definition. Numerical, but not statistically significant trends toward lower NODAT rates with CSWD were observed through 5 years for insulin use, HbA1c ≥6.0% and ≥6.5% on two occasions. This prospective, randomized trial of CSWD indicates that CSWD has a limited impact in reducing NODAT when compared to low-dose prednisone (5 mg/day from month 6 to 5 years).

First-in-human study of the safety and efficacy of TOL101 induction to prevent kidney transplant rejection.

TOL101 is a murine IgM mAb targeting the αß TCR. Unlike other T cell targets, the αß TCR has no known intracellular signaling domains and may provide a nonmitogenic target for T cell inactivation. We report the 6-month Phase 2 trial data testing TOL101 in kidney transplantation. The study was designed to identify a dose that resulted in significant CD3 T cell modulation (<25 T cell/mm(3) ), to examine the safety and tolerability of TOL101 and to obtain preliminary efficacy information. Thirty-six patients were enrolled and given 5-10 daily doses of TOL101; 33 patients completed dosing, while three discontinued after two doses due to a self-limiting urticarial rash. Infusion adjustments, antihistamines, steroids and dose escalation of TOL101 reduced the incidence of the rash. Doses of TOL101 above 28 mg resulted in prolonged CD3 modulation, with rapid recovery observed 7 days after therapy cessation. There were no cases of patient or graft loss. Few significant adverse events were reported, with one nosocomial pneumonia. There were five biopsy-confirmed acute cellular rejections (13.9%); however, no donor-specific antibodies were detected. Overall TOL101 was well-tolerated, supporting continued clinical development using the dose escalating 21-28-42-42-42 mg regimen.

Transfer of peanut IgE sensitisation after combined pancreas-kidney transplant.

BACKGROUND: The transfer of peanut allergy has been reported following solid organ transplantation. OBJECTIVE: Present a case of peanut sensitization following combined pancreas-and-kidney transplantation. METHODS: Circulating specific IgE against peanut were measured in serum samples collected from the transplant recipient 1 month before transplantation, and 1, 3 and 6 months after transplantation. Skin tests were performed 1, 3 and 6 months following transplant. RESULTS: The organ recipient's pre-transplant peanut IgE levels were negative. At 1 month post-transplant, the patient had a 6 mm skin test to peanut and had serum IgE to peanut Arah1 of 0.79 kU/L. At 3 months, skin test size and IgE to peanut Arah1 decreased to 4 mm, and 0.69 kU/L respectively. At 6 months, the patient's skin test and IgE to peanuts were negative. At that time, the patient underwent a peanut food challenge without a clinical reaction to suggest allergy. CONCLUSION AND CLINICAL RELEVANCE: We report the development of IgE peanut sensitization in a recipient of a combined pancreas and kidney transplantation. Increasing awareness of this allergen sensitization following transplantation may help prevent serious allergic reactions in transplant recipients.

Effect of corticosteroid withdrawal on tacrolimus and mycophenolate mofetil exposure in a randomized multicenter study.

As corticosteroid-sparing protocols are increasingly utilized in kidney transplant recipients, it is crucial to understand potential drug interactions between tacrolimus (TAC) and the effect of corticosteroid withdrawal as well as to characterize dose adjustments of mycophenolate mofetil (MMF) in this setting. This prospective, multicenter, randomized, double-blind study included 397 patients who were randomized on posttransplant day 8 to receive either placebo (CSWD) or corticosteroid continuance (CCS). TAC trough levels at week two posttransplant were significantly greater in the CSWD group whereas TAC doses were comparable to the CCS group. This interaction was not observed in the African American subgroup. Higher serum creatinine and potassium levels were also observed in the CSWD group. MMF dose was significantly reduced in the CSWD group by the investigators because of decreased WBC counts, mostly outside of study protocol criteria, despite similar incidence of neutropenia and reported cytomegalovirus infection. Understanding TAC and MMF exposure in the context of corticosteroid-sparing protocols should allow for improved dosing of immunosuppressants and better management of posttransplant patients.

Cytomegalovirus incidence between everolimus versus mycophenolate in de novo renal transplants: pooled analysis of three clinical trials.

Everolimus (EVR) in heart and renal transplant (RTx) recipients may be associated with a decreased incidence of cytomegalovirus (CMV). A detailed analysis of the association between EVR versus mycophenolic acid (MPA) and CMV events has not been reported. CMV data from 2004 de novo RTx recipients from three-randomized, prospective, EVR studies A2309 (N = 833), B201 (N = 588) and B251 (N = 583) were retrospectively analyzed to identify differences between two EVR dosing groups and MPA. EVR groups received 1.5 mg/day, or 3 mg/day with either standard (SD-CsA) or reduced dose cyclosporine (RD-CsA). Controls received MPA with SD-CsA. CMV prophylaxis was as per center practice. CMV incidence (infection/syndrome, disease, viremia) was captured per local center evaluations. Kaplan-Meier analyses demonstrated that freedom from CMV viremia and infection/syndrome was significantly greater for EVR versus MPA for recipients without CMV prophylaxis. Among recipients who received prophylaxis, freedom from viremia was greater for EVR 3.0 mg; freedom from infection/syndrome was greater for EVR 3.0 and 1.5 mg. Although freedom from organ involvement was numerically greater for EVR, it was not statistically significant. This analysis documents significant reductions in the incidence of CMV infection/syndrome and viremia in EVR-treated de novo RTx recipients, especially those who did not receive CMV prophylaxis versus MPA.

Preconditioning: from experimental findings to novel therapies in acute kidney injury.

Improving the ability of the kidney to tolerate injury through preconditioning is likely to have important clinical implications. Although a number of preconditioning strategies have been studied, ischemic preconditioning (IP) has been studied the most experimentally. The information gathered has helped us shed more light into the mechanisms responsible for this tissue adaptation that confers to tissues a more resistant status. IP is effective within minutes, suggesting that preformed mediators are involved. This is followed by delayed preconditioning, a phenomenon that is less potent but longer acting. Remote preconditioning occurs also in non-affected tissues and can be transferable. A number of mediators and transcription factors have been implicated including kinases, heat shock proteins, nitric oxide and neurogenic pathways, all of which help change the cell into a more resistant phenotype. There is evidence that IP also occurs in the human environment with lessons learned from myocardial ischemia, hepatic resection and cerebral ischemia. Because of the ethical impediment with intentionally applying organ ischemia, there has been an interest in pharmacological preconditioning lately. Exogenously administered erythropoietin was shown to benefit kidneys subjected to different insults. In addition, mesenchymal stem cells-based approaches for the prevention and treatment of acute kidney injury (AKI) are being studied. Calcineurin inhibitors may represent a viable way to reduce ischemia reperfusion injury in transplantation. Translating the experimental findings to the clinical arena remains a challenge. The discovery of new biomarkers for AKI should help initiate therapy early, when therapy could make a difference.

Successful treatment of recurrent Henoch-Schönlein purpura in a renal allograft with plasmapheresis.

Acute and severe cases of Henoch-Schönlein purpura (HSP) nephritis have been treated with plasmapheresis (PA) in both adults and children. It has been used either alone or with steroids, antiplatelets or cytoxic drugs. Generally, renal function has been shown to improve when PA is utilized. The role of PA in recurrent HSP after renal transplantation is unclear and has not been well described in the literature. We report a 29-year-old female with HSP who developed end-stage renal disease and subsequently underwent a renal transplantation with eventual loss of the allograft 5 years later due to recurrent HSP nephritis. Retransplantion was performed and the patient developed active HSP nephritis in her second allograft within a week after transplantation. In an effort to preserve her allograft, four cycles of PA were performed. Her proteinuria resolved and renal biopsies afterwards demonstrated marked reduction in mesangial IgA deposition. We conclude that PA may be useful in recurrent HSP nephritis, especially when used early. The risk of additional immunosuppression caused by PA needs to be considered. More studies need to be done to evaluate the efficacy of PA in this setting as well as to define the optimal treatment regimen.

Expression of vascular endothelial growth factor and its receptors Flt-1 and KDR/Flk-1 in chronic cyclosporine nephrotoxicity.

BACKGROUND: Vascular endothelial growth factor (VEGF) is an endothelial cell mitogen involved in angiogenesis, wound healing, and inflammation. METHODS: Rats placed on low salt diet (LSD) or normal salt diet (NSD) were treated with cyclosporine (CsA) or vehicle (VH) and killed at 7 or 28 days. We studied the expression of VEGF and its receptors Flt-1 and KDR/Flk-1 mRNA by Northern and that of VEGF protein by Western blot. RESULTS: CsA induced VEGF mRNA and protein expressions at 7 and 28 days in LSD rats. At 7 days, CsA up-regulated the expression of Flt-1 and KDR/Flk-1 receptors; however, at 28 days, Flt-1 remained unchanged whereas KDR/Flk-1 expression declined. In NSD rats, in which the lesion did not develop, the expression of VEGF and its receptors remained similar to control. CONCLUSIONS: What causes VEGF to be up-regulated remains unclear. Further studies are needed to study the role of hypoxia and other cytokines in relation to VEGF in this model.

Mechanism of fibrosis in experimental tacrolimus nephrotoxicity.

The clinical use of tacrolimus (FK506) is limited by nephrotoxicity. The pathogenesis of fibrosis in chronic FK506 nephrotoxicity remains unknown. Because transforming growth factor (TGF)-beta plays a key role in the fibrogenesis of many diseases, including cyclosporine nephrotoxicity, we studied a salt-depleted rat model of chronic FK506 nephropathy in which clinically relevant FK506 blood levels are obtained and which shows similarities to the lesions described in patients receiving FK506. Pair-fed rats were treated with either FK506 (1 mg/kg/day s.c.) or an equivalent dose of vehicle and were killed at 7 or 28 days. Characteristic histologic changes of tubular injury, interstitial fibrosis, and arteriolopathy developed in FK506-treated rats at 28 days and were accompanied by worsening kidney function, decreased concentrating ability, and enzymuria. FK506-treated kidneys had a progressive increase in the expression of TGF-beta1 and matrix proteins (biglycan, tenascin, fibronectin, and type I collagen). This effect seems to be specific because the expression of type IV collagen, a basement membrane collagen, was not affected. Matrix deposition was present mostly in the tubulointerstitium and vessels in accordance with the FK506 chronic lesion. The expression of plasminogen activator inhibitor-1, a protease inhibitor influenced by TGF-beta, followed TGF-beta1 and matrix proteins, suggesting that the fibrosis of chronic FK506 nephropathy likely involves the dual action of TGF-beta1 on matrix deposition and degradation. Since both peripheral and tissue renin expression were elevated with FK506, the renin-angiotensin system may play a role in the pathogenesis of this condition.

Results of the double-blind, randomized, multicenter, phase III clinical trial of Thymoglobulin versus Atgam in the treatment of acute graft rejection episodes after renal transplantation.

BACKGROUND: Thymoglobulin, a rabbit anti-human thymocyte globulin, was compared with Atgam, a horse anti-human thymocyte globulin for the treatment of acute rejection after renal transplantation. METHODS: A multicenter, double-blind, randomized trial with enrollment stratification based on standardized histology (Banff grading) was conducted. Subjects received 7-14 days of Thymoglobulin (1.5 mg/kg/ day) or Atgam (15 mg/kg/day). The primary end point was rejection reversal (return of serum creatinine level to or below the day 0 baseline value). RESULTS: A total of 163 patients were enrolled at 25 transplant centers in the United States. No differences in demographics or transplant characteristics were noted. Intent-to-treat analysis demonstrated that Thymoglobulin had a higher rejection reversal rate than Atgam (88% versus 76%, P=0.027, primary end point). Day 30 graft survival rates (Thymoglobulin 94% and Atgam 90%, P=0.17), day 30 serum creatinine levels as a percentage of baseline (Thymoglobulin 72% and Atgam 80%; P=0.43), and improvement in posttreatment biopsy results (Thymoglobulin 65% and Atgam 50%; P=0.15) were not statistically different. T-cell depletion was maintained more effectively with Thymoglobulin than Atgam both at the end of therapy (P=0.001) and at day 30 (P=0.016). Recurrent rejection, at 90 days after therapy, occurred less frequently with Thymoglobulin (17%) versus Atgam (36%) (P=0.011). A similar incidence of adverse events, post-therapy infections, and 1-year patient and graft survival rates were observed with both treatments. CONCLUSIONS: Thymoglobulin was found to be superior to Atgam in reversing acute rejection and preventing recurrent rejection after therapy in renal transplant recipients.

Cyclosporine nephropathy: pathophysiology and clinical impact.

Cyclosporine (CsA) has markedly improved the results of transplantation, and its use has been extended to include autoimmune and primary renal diseases. However, the major limitation to its nephrotoxicity. Acutely, a reversible form of renal vasoconstriction can occur in all patients receiving CsA. In addition, progressive renal insufficiency owing to CsA has also been well documented. Clinically, long-term CsA nephrotoxicity is characterized by slowly progressive azotemia, proteinuria, and hypertension. Histologically, there is striped tubulointerstitial fibrosis, tubular atrophy, and afferent arteriolopathy. New evidence suggests that the histological changes in long-term CsA nephropathy are independent of the functional changes. Recently transforming growth factor (TGF)-beta was shown to be upregulated along with matrix proteins in a model of CsA nephrotoxicity. Because TGF-beta has immunosuppressive activities, it was suggested that it may contribute not only to CsA nephrotoxicity, but also to the mechanism of action of CsA. A number of strategies have been devised to try to minimize CsA nephrotoxicity, but remain inconclusive. Presently, it is not clear what role CsA therapy plays in the chronic failure of renal allografts. Continued research should give new insights into measures to overcome CsA-induced scarring in the kidney.

Effect of some syrup constituents on the solubility of sorbic acid.

The effects of sucrose, glucose, sorbitol, and saccharin on the aqueous solubility of sorbic acid at 20 and 37 degrees C were determined. Sucrose, glucose, and sorbitol decreased the solubility of sorbic acid with increasing concentrations at both temperatures. Increasing the concentrations of these sweetening agents resulted in decreases in the dielectric constants. Calculation of the free energy and enthalpy changes indicated that the dissolution process for sorbic acid became progressively unfavorable with increasing sugar concentration.

Percutaneous diffusion of cefalexin, sulfamethoxazole and diphenhydramine from ointments.

The effects of ointment base, drug concentration, and the presence of surfactant on the diffusion of cefalexin, sulfamethoxazole and diphenhydramine through excised mouse skin were studied. The total amount of diffused drug per ml against time and against the square root of time as plotted for the evaluation of results. As was expected from theory, a linear relationship was obtained for each drug when the square root of time was employed. The effect of the vehicle on the release of cefalexin was in the following decreasing order: o/w emulsion greater than water-soluble greater than hydrophilic greater than oleaginous greater than w/o emulsion base. That on the release of sulfamethoxazole was in the order: water-soluble greater than o/w emulsion greater than w/o emulsion = oleaginous = hydrophilic. The order in case of diphenhydramine was as follows: o/w emulsion greater than water-soluble greater than hydrophilic greater than oleaginous = w/o emulsion. The increase in drug concentration or the addition of a surfactant has caused an increase in the diffusion rate of each of the drugs.