Rationale for using belatacept in combination with sirolimus

Kidney transplantation can be used to replace failing native kidneys; however, it requires long-term immunosuppression, and immunological tolerance for this is not yet achievable. The cornerstone of immunosuppression is based on calcineurin inhibitors, which are nephrotoxic. Therefore, new drugs are being developed that provide efficacious immunosuppression and almost no renal toxicity. The first family of drugs that have these properties are mammalian target of rapamycin inhibitors: these include sirolimus and everolimus. These two drugs, besides their immunosuppressive properties, also have beneficial effects regarding cytomegalovirus (CMV) infection, which is a very common posttransplantation complication. In phase III trials, belatacept, a costimulatory blocker, has also been shown to provide a good immunosuppressive effect and also gives a significantly better cardiovascular profile than cyclosporine-based immunosuppression. However, belatacept can potentially increase infections such as CMV. Thus, herein, we describe the rationale for combining belatacept with sirolimus for kidney transplant patients.

Duodenal villous atrophy: a cause of chronic diarrhea after solid-organ transplantation

Persistent diarrhea is commonly observed after solid organ transplantation (SOT). A few cases of mycophenolate mofetil (MMF)-induced duodenal villous atrophy (DVA) have been previously reported in kidney-transplant patients with chronic diarrhea. Herein, we report on the incidence and characteristics of DVA in SOT patients with chronic diarrhea. One hundred thirty-two SOT patients with chronic diarrhea underwent an oesophago-gastroduodenoscopy (OGD) and a duodenal biopsy after classical causes of diarrhea have been ruled out. DVA was diagnosed in 21 patients (15.9%). It was attributed to mycophenolic acid (MPA) therapy in 18 patients (85.7%) (MMF [n = 14] and enteric-coated mycophenolate sodium [n = 4]). MPA withdrawal or dose reduction resulted in diarrhea cessation. The incidence of DVA was significantly higher in patients with chronic diarrhea receiving MPA compared to those who did not (24.6% vs. 5.1%, p = 0.003). DVA was attributed to a Giardia lamblia parasitic infection in two patients (9.5%) and the remaining case was attributed to azathioprine. In these three patients, diarrhea ceased after metronidazole therapy or azathioprine dose reduction. In conclusion, DVA is a frequent cause of chronic diarrhea in SOT recipients. MPA therapy is the most frequent cause of DVA. An OGD should be proposed to all transplant recipients who present with persistent diarrhea.

Viral infections after kidney transplantation

Chronic immunosuppression, required to maintain allograft function postorgan transplant, predisposes transplant patients to a variety of viral infections. These can occur at every stage of post-transplantation. Some infections, however, such as cytomegalovirus (CMV), Epstein Barr virus (EBV), or BK virus (BKV), tend to occur within months after transplantation. CMV infections can be easily prevented by prophylaxis therapy whereas EVB or BKV infections can be prevented by lowering (when possible) immunosuppression. Some viral infections can result in posttransplant lymphoproliferative disorders (EBV), Kaposi sarcoma (human herpes simplex virus type 8), or skin and/or cervical cancers (papillomavirus). Other viral infections, such as those due to influenza or para influenzae viruses, respiratory syncytial virus, or West nile fever virus, are mostly acquired through environmental spread. Thanks to modern laboratory technique, and a formidable antiviral armamentarium, viral infections in organ transplant patients i) can be easily detected at early stages, and ii) can be efficiently treated.

[Pneumocystis jiroveci infection associated with organizing pneumonia in a kidney transplant patient]

The authors report the association of organizing pneumonia (OP) and a Pneumocystis jiroveci infection in a woman who benefited from a kidney transplant 13 years before and was under corticoids, cyclosporine and mycophenolate mofetil. The diagnosis was based on progressive dyspnoea with fever with an alteration in the general state associated with diffuse micronodular pneumopathy suggesting bronchiolitis. The conformation was obtained by the analysis of the alveolar bronchial washings and the histological examination of the distal biopsies revealing endo-alveolar vegetant fibromas. Transbronchial biopsies may be used for the diagnosis and thereby, avoid an invasive surgical pulmonary biopsy. The aetiology of OP may be related to the immunosuppressant treatment or infection by Pneumocystis jiroveci. The evolution in this case was favourable with trimethoprime and sulfamethoxazole associated with a transient increase in the corticoid treatment. This association is rarely described in patients undergoing solid organ transplants.

Indications for and barriers to preemptive kidney transplantation: a review

Preemptive kidney transplantation is the treatment of choice for end-stage renal disease. Compared with nonpreemptive transplantation, preemptive transplantation is significantly associated with improved kidney allograft survival in recipients of either cadaver or living-donor transplants. This seems to be related to better patient survival. It can be proposed to all patients, but still needs to be evaluated for repeat transplantation. The main barriers are organ-allocation policies and late referral of patients to transplantation centers.

High dose epoetin beta in the first weeks following renal transplantation and delayed graft function: Results of the Neo-PDGF Study

Erythropoietin promotes nephroprotection in animal models of ischemia-reperfusion injury. Neorecormon and Prevention of Delayed Graft Function (Neo-PDGF) is a French open-label multicenter randomized study to evaluate the effect of high doses of epoetin beta (EPO-beta) during the first 2 weeks of renal transplantation on renal function in patients at risk for delayed graft function (DGF). One hundred and four patients were included in the study. Patients randomized in treatment group (A) received four injections of EPO-beta (30.000 UI each), given before surgery and at 12 h, 7 days and 14 days posttransplantation. Patients randomized in control group (B) did not receive EPO-beta. Immunosuppression included induction with basiliximab and maintenance therapy with steroids, mycophenolate mofetil and tacrolimus. At 1 month posttransplant, the estimated glomerular filtration rate (MDRD formula) was 42.5 +/- 19.0 mL/min in the EPO-beta group and 44.0 +/- 16.3 mL/min in the control group (p = ns). The frequency of DGF was similar in both groups (32% vs. 38.8%; p = ns). No difference in the incidence of serious adverse events was observed. (ClinicalTrials.gov number, NCT00815867.).

Hepatitis E virus-induced neurological symptoms in a kidney-transplant patient with chronic hepatitis

It has been shown that hepatitis E virus (HEV) may be responsible for chronic hepatitis in solid-organ transplant patients. It has also been suggested that HEV may be responsible for atypical neurological symptoms during the acute phase. However, the relationship between the neurological symptoms and HEV infection was based on the detection of anti-HEV IgM in the sera. Herein, we report a case where neurological symptoms, that is peripheral nerve involvement with proximal muscular weakness that affected the four limbs joints with central nervous-system involvement and bilateral pyramidal syndrome, occurred in a kidney-transplant patient who was chronically infected by HEV. For the first time, HEV RNA was detected in the serum and cerebrospinal fluid. In addition, clonal HEV sequences were analyzed in both compartments, that is serum and cerebrospinal fluid. The discovery of quasispecies compartmentalization and its temporal association suggests that neurological symptoms could be linked to the emergence of neurotropic variants.

A phase III study of belatacept-based immunosuppression regimens versus cyclosporine in renal transplant recipients (BENEFIT study)

Belatacept, a costimulation blocker, may preserve renal function and improve long-term outcomes versus calcineurin inhibitors in kidney transplantation. This Phase III study (Belatacept Evaluation of Nephroprotection and Efficacy as First-line Immunosuppression Trial) assessed a more intensive (MI) or less intensive (LI) regimen of belatacept versus cyclosporine in adults receiving a kidney transplant from living or standard criteria deceased donors. The co-primary endpoints at 12 months were patient/graft survival, a composite renal impairment endpoint (percent with a measured glomerular filtration rate (mGFR) <60 mL/min/1.73 m(2) at Month 12 or a decrease in mGFR > or =10 mL/min/1.73 m(2) Month 3-Month 12) and the incidence of acute rejection. At Month 12, both belatacept regimens had similar patient/graft survival versus cyclosporine (MI: 95%, LI: 97% and cyclosporine: 93%), and were associated with superior renal function as measured by the composite renal impairment endpoint (MI: 55%; LI: 54% and cyclosporine: 78%; p < or = 0.001 MI or LI versus cyclosporine) and by the mGFR (65, 63 and 50 mL/min for MI, LI and cyclosporine; p < or = 0.001 MI or LI versus cyclosporine). Belatacept patients experienced a higher incidence (MI: 22%, LI: 17% and cyclosporine: 7%) and grade of acute rejection episodes. Safety was generally similar between groups, but posttransplant lymphoproliferative disorder was more common in the belatacept groups. Belatacept was associated with superior renal function and similar patient/graft survival versus cyclosporine at 1 year posttransplant, despite a higher rate of early acute rejection.

Incidence and predictive factors for infectious disease after rituximab therapy in kidney-transplant patients

Rituximab off-label use includes organ transplantation. We review the occurrence of infectious disease and its outcome after rituximab therapy. Between April 2004 and August 2008, 77 kidney-transplant patients received rituximab therapy [2-8 courses (median 4) of 375 mg/m2 each] for various reasons. Their results were compared with a control group (n=902) who had received no rituximab. After a median follow-up of 16.5 (1-55) months for rituximab patients and 60.9 (1.25-142.7) months for control patients, the incidence of infectious disease was 45.45% and 53.9% (ns), respectively. The incidence of bacterial infection was similar between the two groups, whereas the viral-infection rate was significantly lower, and the rate of fungal infection was significantly higher in the rituximab group. Nine out of 77 patients (11.68%) died after rituximab therapy, of which seven deaths (9.09%) were related to an infectious disease, compared to 1.55% in the controls (p=0.0007). In the whole population, the independent predictive factors for infection-induced death were the combined use of rituximab and antithymocyte-globulin given for induction or anti-rejection therapy, recipient age, and bacterial and fungal infections. After kidney transplantation, the use of rituximab is associated with a high risk of infectious disease and death related to infectious disease.

HLA class I antibodies provoke graft arteriosclerosis in human arteries transplanted into SCID/beige mice

Antibodies toward HLA class I and/or MICA are commonly observed in transplanted patients suffering from allograft arteriosclerosis, also called chronic vascular rejection (CVR). The relative importance of cellular versus humoral alloreactivity for CVR is still disputed. We demonstrate that antibodies toward HLA class I provoke lesions typical for CVR in human arteries in vivo in the absence of cellular immunity. To show this, we grafted segments of human mesenteric arteries from 8 deceased organ donors into 36 immunodeficient SCID/beige mice in the infrarenal aortic position. Three mice died postoperatively. The remaining 33 mice received weekly i.v. injections of either a monoclonal antibody toward HLA class I, toward MICA or an irrelevant monoclonal antibody. At sacrifice after 6 weeks, mice receiving the HLA antibody showed a significant neointimal thickening in the grafted artery due to smooth muscle cell (SMC) proliferation while control mice receiving anti-MICA or irrelevant antibody showed little or no thickening. Whereas antibodies toward HLA class I were mitogenic to SMC in vitro, those directed toward MICA did not have any effect. Humoral alloreactivity toward HLA may thus play a causal role for the development of CVR and this opens new possibilities for the treatment of CVR.

[Domino transplantation of a living-donor kidney graft affected by thrombotic microangiopathy: surgical aspects]

We report surgical aspects of the first case of retransplantation of a kidney initially retrieved from a cadaveric donor, then on a first recipient which developed a recurrent severe and intractable thrombotic microangiopathy on the allograft.

Biological changes after liver transplantation according to the presence or not of graft steatosis

AIM

To assess the consequences of graft steatosis on postoperative liver function as compared with normal liver grafts.

PATIENTS AND METHODS

From January 2005 to December 2007, liver transplant patients were prospectively included, excluding those who experienced arterial or biliary complications or presented acute rejection. All patients had a surgical biopsy after reperfusion. Patients were compared according to the rate of macrovacuolar steatosis: namely above or below 20%.

RESULTS

Fifty-three patients were included: 10 in the steatosis group and 43 in the control group. No significant difference was observed in terms of morbidity, mortality, and primary non- or poor function. Nevertheless, biological changes after the procedure were significantly different during the first postoperative week. Prothrombin time, serum bilirubin, and transaminases were significantly increased among the steatosis group compared with the control group (P < .05).

CONCLUSION

This case-controlled study including a small number of patients, described postoperative biological changes among liver transplantations with steatosis in the graft.

Delayed introduction of reduced-dose tacrolimus, and renal function in liver transplantation: the 'ReSpECT' study

We report a multicenter, prospective, randomized, open-label trial investigating the effect of lower levels and delayed introduction of tacrolimus on renal function in liver transplant recipients. Adult patients with good renal function undergoing primary liver transplant were randomized to either: group A (standard-dose tacrolimus [target trough levels >10 ng/mL] and corticosteroids; n = 183); group B (mycophenolate mofetil [MMF] 2g/day, reduced-dose tacrolimus [target trough levels </=8 ng/mL], and corticosteroids; n = 170); group C (daclizumab induction, MMF, reduced-dose tacrolimus delayed until the fifth day posttransplant and corticosteroids, n = 172). The primary endpoint was change from baseline in estimated glomerular filtration rate (eGFR) at 52 weeks. The eGFR decreased by 23.61, 21.22 and 13.63 mL/min in groups A, B and C, respectively (A vs C, p = 0.012; A vs B, p = 0.199). Renal dialysis was required less frequently in group C versus group A (4.2% vs. 9.9%; p = 0.037). Biopsy-proven acute rejection rates were 27.6%, 29.2% and 19.0%, respectively. Patient and graft survival was similar. In conclusion, daclizumab induction, MMF, corticosteroids and delayed reduced-dose tacrolimus was associated with less nephrotoxicity than therapy with standard-dose tacrolimus and corticosteroids without compromising efficacy or tolerability.

Nitric oxide production by the alveolar compartment of the lungs in cirrhotic patients

In cirrhotic patients, alveolar nitric oxide (NO) concentration is increased. This may be secondary to increased output of NO produced by the alveoli (V'(A,NO)) and/or to decreased lung transfer factor of NO. In advanced liver cirrhosis, NO produced by the alveoli may play a role in abnormalities of pulmonary haemodynamics and gas exchanges. In cirrhotic patients, we aimed to measure V'(A,NO) and to compare V'(A,NO) with pulmonary haemodynamics and gas exchange parameters. Measurements were performed in 22 healthy controls and in 29 cirrhotic patients, of whom eight had hepatopulmonary syndrome. Exhaled NO concentrations were measured at multiple expiratory flow rates to derive alveolar NO concentration. V'(A,NO) was the product of alveolar NO concentration by single breath lung transfer factor for NO. V'(A,NO) was increased in patients (median (range) 260 (177-341) nL x min(-1)) compared with controls (79 (60-90), p<0.0001). Alveolar-arterial oxygen tension difference failed to correlate with V'(A,NO). However, cardiac index correlated positively and systemic vascular resistance correlated negatively with V'(A,NO) (r = 0.56, p = 0.001 and r = -0.52, p = 0.004, respectively). In cirrhotic patients, NO was produced in excess by the alveolar compartment of the lungs. Alveolar NO production was associated with hyperdynamic circulatory syndrome but not with arterial oxygenation impairment.