Superior rejection profile during the first 24 months after heart transplantation under tacrolimus as baseline immunosuppressive regimen.

BACKGROUND: The use of tacrolimus (TAC) in patients after heart transplantation (HTX) has increased over the last few years. AIM: In this retrospective study, we evaluated the effects of a TAC (conventional and extended-release TAC)-based immunosuppressive therapy regarding rejection profile in comparison to a cyclosporine A (CSA)-based regimen in patients after HTX. METHODS: The data of 233 patients who underwent HTX at the Heidelberg Heart Transplantation Center from May 1998 until November 2010 were retrospectively analyzed. Primary immunosuppressive therapy was changed from a CSA (n=114) to a TAC (n=119)-based regimen in February 2006 according to center routine. Follow-up period was 2 years post-HTX. Primary endpoint was time to first biopsy-proven rejection requiring therapy. In all patients, routine follow-up at the Heidelberg Heart Transplantation Center was mandatory. RESULTS: Multivariate risk factor analysis regarding time to first rejection episode showed no statistically significant differences regarding recipient age, donor age, recipient sex, donor sex, sex mismatch, ischemic time, and diagnosis leading to HTX between the two groups (all P= not statistically significant). Time to first biopsy-proven rejection was significantly longer in the TAC group (intention-to-treat analysis, n=233, log-rank test P<0.0001; per-protocol analysis, n=150, log-rank test P=0.0003). In patients who underwent a change of primary immunosuppression (n=49), a significantly longer time to first biopsy-proven rejection was also found in the primary TAC subgroup (log-rank test P=0.0297). Further subgroup analysis in the TAC subgroups showed no statistically significant differences in time to biopsy-proven rejection under extended-release TAC compared to conventional TAC (intention-to-treat analysis, log-rank test P=0.1736). CONCLUSION: Our study demonstrated that a TAC-based primary immunosuppressive therapy is superior to a CSA-based immunosuppressive regimen in patients after HTX regarding time to first biopsy-proven rejection.

Azathioprine hypersensitivity syndrome: a case report.

We report here the case of a 51-year-old man presenting to the Emergency Department with a febrile cutaneous eruption with diffuse arthralgia 10 days after the onset of azathioprine therapy. The clinical examination did not reveal any inflammatory syndrome and the results of all bacteriological tests were negative. A skin biopsy was performed, which revealed a granulocytary pustula with superficial dermal oedema and a neutrophil infiltration without sign of vasculitis. A side effect of azathioprine was suspected, and treatment was discontinued. Fortunately, the patient recovered within a few days. Azathioprine hypersensitivity syndrome is a rare side effect of azathioprine. Hypersensitivity syndrome is an idiosyncratic, non-IgE-mediated reaction that appears to be unrelated to thiopurine methyltransferase levels. Diagnosis is mainly clinical and requires an exclusion of other processes. The only treatment option available is to stop azathioprine intake.

What does the future hold for clinical studies in vasculitis?

The era prior to 1990 was a time of careful observation of disease presentation, course, outcomes and meticulous pathology studies. These mainly single-centre studies introduced new life-saving therapies for drugs still used effectively today. In the 1970-1980s, cyclophosphamide (CyP) added to glucocorticosteroids (GCS) was shown to be life-saving. The trade-off was often severe adverse events. Some forms of vasculitis were found not as ominous as thought initially. Some could be treated with safer drugs [e.g. methotrexate (MTX)]. However, whether mild or severe, patients were not cured. From 1990 to the present large collaborative networks have provided studies were not possible heretofore. Randomized controlled trials captured and manipulated vast amounts of data, banked biological specimens and shared these resources and intellectual capital, moving the field forward at an extraordinary pace. We now know that even for severe forms of granulomatosis and polyangiitis [granulomatosis with polyangiitis (GPA), Wegener's granulomatosus (WG)], microscopic polyangiitis (MPA) and Churg-Strauss syndrome (CSS), we do not need to use CyP for extended periods. We have learned recently that rituximab is as effective as CyP for severe WG and MPA. We should never again see the permanent toxicities born from years of chronic CyP use. However, short courses of CyP remain useful and can be life-saving. Step-down therapy from CyP is now a standard of care, perhaps to be replaced by rituximab in the future. If one accepts the premise that there are few cures at present for idiopathic large- and small-vessel vasculitis, we will serve our patients well if we can determine the most effective initial therapy that leads to a maintenance strategy for remission with least risk. Ultimately, we wish to identify causes of vasculitis so they can be used as a wedge to secure cures. Unmet needs and strategies are as follows: (1) to increase the numbers of vasculitis-trained physicians; (2) to define risk-benefit formulae for chronic maintenance therapy versus discontinuation of treatment after remission; (3) to define risk- and cost-benefit formulae for laboratory monitoring; (4) large-scale studies with longer follow-up that explore inhibition of interleukin-5 in CSS; (5) to explore the value of anti-interferon-γ for GCA, Takayasu's and other granulomatous vasculitides; and (6) identification of aetiological factors: cures will probably be linked to knowledge of the antigen driving the disease, plus vulnerabilities of the patient that prepare them to develop an illness phenotype. Improved outcomes using anti-inflammatory/immunosuppressive agents do not rule out infection as a driver for autoimmunity. Techniques that can facilitate pathogen discovery have never been more sophisticated.

Laboratory evaluation of inflammatory bowel disease.

PURPOSE OF REVIEW: Recognizing inflammatory bowel disease (IBD) is straightforward when alarm symptoms are present, such as bloody diarrhea and weight loss. When the presentation is subtle or atypical, physicians must determine which patients warrant evaluation for IBD. Appropriate use of noninvasive tests can help identify which patients should undergo further investigation. RECENT FINDINGS: Currently IBD serologies lack high enough sensitivity and specificity to make them useful as a screening test for distinguishing IBD from other disorders, but they may have a role in classifying subtypes of IBD. Fecal markers seem promising for helping to differentiate IBD from irritable bowl syndrome and for monitoring disease activity. Pharmacogenetically guided dosing is recommended for safe use of thiopurines but ongoing routine laboratory monitoring remains important. Thiopurine metabolite measurement can be useful but may not be needed in all cases. SUMMARY: Primary care physicians should continue to rely on routine laboratory tests and clinical suspicion to decide which patients with abdominal pain to refer to a gastroenterologist. Serology panels are not useful for IBD screening as the results may lead to unnecessary procedures. Although fecal markers do show promise as a screening test for IBD, patient resistance to providing stool samples may limit its usefulness in disease monitoring. Thiopurine metabolite levels are best used in conjunction with clinical status and routine laboratory tests to monitor clinical response and adverse events.

Pharmacogenomic studies of the anticancer and immunosuppressive thiopurines mercaptopurine and azathioprine.

AIMS: To examine the allelic variation of three enzymes involved in 6-mercaptopurine/azathioprine (6-MP/AZA) metabolism and evaluate the influence of these polymorphisms on toxicity, haematological parameters and metabolite levels in patients with acute lymphoblastic leukaemia (ALL) or inflammatory bowel disease (IBD). METHODS: Clinical data and blood samples were collected from 19 ALL paediatric patients and 35 IBD patients who were receiving 6-MP/AZA therapy. All patients were screened for seven genetic polymorphisms in three enzymes involved in mercaptopurine metabolism [xanthine oxidase, inosine triphosphatase (C94-->A and IVS2+21A-->C) and thiopurine methyltransferase]. Erythrocyte and plasma metabolite concentrations were also determined. The associations between the various genotypes and myelotoxicity, haematological parameters and metabolite concentrations were determined. RESULTS: Thiopurine methyltransferase variant alleles were associated with a preferential metabolism away from 6-methylmercaptopurine nucleotides (P = 0.008 in ALL patients, P = 0.038 in IBD patients) favouring 6-thioguanine nucleotides (6-TGNs) (P = 0.021 in ALL patients). Interestingly, carriers of inosine triphosphatase IVS2+21A-->C variants among ALL and IBD patients had significantly higher concentrations of the active cytotoxic metabolites, 6-TGNs (P = 0.008 in ALL patients, P = 0.047 in IBD patients). The study confirmed the association of thiopurine methyltransferase heterozygosity with leucopenia and neutropenia in ALL patients and reported a significant association between inosine triphosphatase IVS2+21A-->C variants with thrombocytopenia (P = 0.012). CONCLUSIONS; Pharmacogenetic polymorphisms in the 6-MP pathway may help identify patients at risk for associated toxicities and may serve as a guide for dose individualization.

Lymphoma after living donor kidney transplantation: an Iranian multicenter experience.

INTRODUCTION: Post-transplant lymphoproliferative disorders (PTLD) are well-recognized complications in solid organ recipients. Limited data exist about the development of PTLDs in living kidney recipients. This study deals with a multicenter nationwide experience with kidney recipients from living donors. METHODS: We reviewed data of PTLD patients from a total population of 6,500 patients transplanted at three different transplant centers in Iran from 1984 to 2006. We also compared their data with 2,250 normal kidney recipients of Baqiyatallah Transplant Center. Data were analyzed to determine potential correlates with the occurrence of PTLD and patient outcome. RESULTS: Overall, 31 patients were diagnosed as having post-transplant lymphomas. The incidence of PTLD in our kidney transplant population comprised 0.47%. Sixteen (53%) PTLD patients were females, whereas 15 (47%) were males. The mean ages at transplantation and diagnosis were 37.1 and 41.9, respectively. Twelve (63%) patients died, and seven are alive. All deaths occurred within the 1st year after PTLD diagnosis. The mean time period from transplantation to diagnosis of PTLD was 64 (0.7-173) months. Localization of PTLD in the brain associated the worst outcome. Compared to non-PTLD patients, PTLD patients were significantly female predominated (51.6% vs. 32.2%; P = 0.03) and had lower age at transplantation (36.9 years vs. 42.9 years, respectively; P = 0.01). Patients under immunosuppressive regimens containing azathioprine were at higher risk for acquiring PTLDs compared to those with a MMF-containing regimen. CONCLUSION: PTLD is a major threat to kidney transplant recipients. Immunosuppressive agents have a significant role in developing the disease. Early detection of the disease and using more safe immunosuppresants may have beneficial effects on patient outcomes and incidence of the disease.

After discontinuation of calcineurin inhibitors, tapering of mycophenolate mofetil further impairs donor-directed cytotoxicity.

BACKGROUND: Recently, we described a significant decrease in donor-specific cytotoxic T-lymphocyte precursor frequency (CTLpf) after discontinuation of calcineurin inhibitors (CNI), while the proliferative capacity in mixed lymphocyte culture (MLC), and the number of interferon-gamma (IFN-gamma) producing cells (pc) in Elispot remained unchanged. METHODS: We tested T-cell reactivity in CNI free patients with stable renal graft function, on mycophenolate mofetil (MMF) or azathioprine (AZA) plus prednisone, who were tapered to 50% of their MMF or AZA dose. RESULTS: Furthermore, tapering of the MMF or AZA dose resulted in a decrease of donor-reactive CTLpf in all patients with detectable CTLpf. Detectable numbers decreased from a median of 32 to 8 CTLp/10(6) peripheral blood mononuclear cell (PBMC). No effect on third-party reactive CTLpf was found, while the T-cell reactivity to donor and third-party cells as tested in MLC and in IFN-gamma Elispot was not affected either by tapering of immunosuppression. Third-party reactivity was significantly higher than donor-specific reactivity in all tests. A control group showed no changes in any of the in vitro assays. CONCLUSION: Both withdrawal of CNI and tapering of MMF or AZA dose decreases the donor-specific CTLpf. Our data suggest that reduction of immunosuppression results in a specific decrease of donor-directed cytotoxic capacity of immunocompetent cells, while their proliferation and cytokine production capacity remained unchanged. Immunosuppression hinders development of cytotoxic non-responsiveness.

Immunosuppressive drugs in ulcerative colitis: twisting facts to suit theories?

Immunosuppressive drugs have become a mainstay of therapy for the inflammatory bowel diseases. Although robust evidence exists in support of the use of these drugs in Crohn's disease, a close evaluation of the available data in ulcerative colitis reveals a much weaker evidence base. In particular, randomised controlled trials of azathioprine, the most commonly used immunosuppressive agent, do not provide rich evidence of efficacy whereas observational cohorts suggest this agent is effective, particularly in patients with relapsing disease who require corticosteroids. Ciclosporin is also effective in the most refractory cases but its efficacy needs to be carefully weighed against the possibility of rare but life threatening complications. Although the evidence base in support of immunosuppressive drugs in ulcerative colitis is not as strong as in Crohn's disease, these agents clearly have a role in the treatment of this disease.

Economic evaluation of everolimus vs. azathioprine at one year after de novo heart transplantation.

BACKGROUND: Everolimus decreases acute rejection and cardiac allograft vasculopathy after heart transplantation. We compared within-trial costs and resource use over 1 yr of follow-up in de novo heart transplant patients randomized to everolimus 1.5 mg/d (n = 209), everolimus 3.0 mg/d (n = 211), or azathioprine (n = 214). PATIENTS AND METHODS: Resource use data were collected prospectively for 634 patients from 14 countries. We used the nonparametric bootstrap method to test for differences in mean costs and to estimate confidence intervals for cost-effectiveness ratios. RESULTS: Everolimus patients had lower incidence of efficacy failure compared with azathioprine patients (41.6%, everolimus 1.5 mg; 32.2%, everolimus 3.0 mg; 52.8%, azathioprine). Compared with patients receiving azathioprine, everolimus patients spent more days in the hospital [36.3 d for everolimus 1.5 mg/d (p = 0.21); 38.4 d for everolimus 3.0 mg/d (p = 0.01); 32.2 d for azathioprine]. Mean total costs, excluding the study medications, were not significantly different among treatment groups ($72 065 for everolimus 1.5 mg; $72 631 for everolimus 3.0 mg; $70 815 for azathioprine). CONCLUSIONS: Over 1 yr of follow-up after heart transplantation, everolimus did not significantly increase treatment costs, excluding the costs of the study medications, while reducing efficacy failure. Longer follow-up and the cost of everolimus are required to fully evaluate the cost-effectiveness of everolimus vs. azathioprine in post-transplant maintenance.

Treatment of autoimmune hepatitis.

Corticosteroid therapy is effective in all forms of autoimmune hepatitis, and the combination of prednisone and azathioprine is preferred. Remission can be achieved in 80% of patients within 3 years, and the 10- and 20-year survival rates exceed 80%. Histological cirrhosis does not affect response or longevity, and all patients with severe disease should be treated, including children, elderly adults, postmenopausal women, individuals with acute or fulminant presentations, and those without conventional autoantibodies. Relapse is common, and long-term low-dose prednisone or azathioprine therapy is preferred after multiple relapses. Sustained remission is achievable, even after relapse, in 47% within 10 years, and the long-term maintenance regimens need not be indefinite. Liver transplantation is effective, and its actuarial 10-year survival rate is 75%. Drugs such as cyclosporine, tacrolimus, and mycophenolate mofetil promise greater blanket immunosuppression, and site-specific interventions are feasible, including blocking peptides, soluble cytotoxic T lymphocyte antigen-4, cytokine manipulations, T cell vaccination, oral tolerance, and gene therapy.

Mycophenolate mofetil decreases antibody production after cardiac transplantation.

New immunosuppressive drugs are extensively being investigated for their effect on T-cell immunity, with far less being known about their effect on the humoral immune response. In view of the experimental and clinical evidence that humoral immunity contributes to acute and chronic rejection, we investigated post-transplant production of anti-vimentin and anti-HLA antibodies in 86 patients who were part of a worldwide clinical trial for mycophenolate mofetil in cardiac transplantation. The results demonstrate that patients taking MMF instead of azathioprine generated significantly fewer de novo anti-vimentin antibodies.

Desensitization to azathioprine.

Azathioprine is an immunosuppressant drug which is an analog to 6-mercaptopurine and has been used in the last 20 years to prevent organ transplant rejection. It has also been used in the treatment of some autoimmunological diseases. We present a case of a 24-year-old woman with systemic lupus erythematosus, suffering from nephritis, who developed angioedema after using azathioprine to control her illness. She had never reported similar episodes. The involvement of the drug was demonstrated by positive oral challenge test without changes in biochemical and complement blood determinations. She reached tolerance to the drug after a desensitization procedure (increasing 5 mg each day to reach 125 mg daily). We are not able to propose the involvement of an IgE-mediated mechanism, but rather a hypersensitive one with a non-dose-dependent effect. These desensitization procedures show great potential as therapeutic safeguards against harmful drugs in some patients. We have not found any other desensitization procedure for this drug.

Allergic reactions to 6-mercaptopurine during treatment of inflammatory bowel disease.

Hypersensitivity reactions to 6-mercaptopurine (6-MP) or azathioprine occur during the treatment of inflammatory bowel disease (IBD), raising significant diagnostic and therapeutic challenges. Charts of 591 patient with IBD treated with 6-MP in a single center were retrospectively reviewed. All allergic reactions were recorded along with results of rechallenge, desensitization, and subsequent course of IBD. Sixteen (2.7%) allergic reactions to 6-MP were noted, with fever being the most common (14 cases). Nine of these were rechallenged with 6-MP with recurrence of the same symptoms. Azathioprine was tried in six patients and in five the same symptoms recurred. Four patients underwent successful desensitization to either 6-MP or azathioprine; all four plus another patient who tolerated direct switch to azathioprine entered long-term remission. Among the remaining 11, 5 required surgery, 2 are well on methotrexate, and 4 have chronic symptoms while being treated with other medications. If an allergic reaction to 6-MP occurs during the treatment of IBD, direct switching to azathioprine is probably not justified. Instead, desensitization to either 6-MP or azathioprine should be attempted. Patients who can tolerate these medications after previous allergic reactions have improved outcomes compared with patients who resort to other forms of treatment.

Standardized estimates from categorical regression models.

We consider the problem of interpreting categorical regression models, such as the polytomous logistic model, the continuation-ratio model, the stereotype model, and the cumulative-odds model. We present a method to convert categorical regression coefficients into estimates of standardized fitted probabilities, probability differences and probability ratios. We use a delta-method approach to estimate standard errors. We then present a small simulation study to compare different transforms for setting confidence limits, and provide an illustration of our approach in an observational study of drug therapy of polymyositis.

[The effect of azathioprine treatment on IgG subclasses in multiple sclerosis]. / Wplyw leczenia azatiopryna na podklasy IgG w stwardnieniu rozsianym.

IgG and its subclasses: IgG1, IgG2, IgG3 and IgG4 were determined in the CSF and sera from 20 patients with multiple sclerosis before and after treatment with azathioprine. The effect of the treatment on IgG and IgG subclasses intrathecal synthesis was studied as well. There was a decrease in IgG level in the CSF of MS patients after the treatment with azathioprine. This was mainly due to the decrease of IgG1 and IgG2 subclasses levels. There was no evidence of the influence of azathioprine treatment on IgG and its subclasses levels in MS sera as well as on IgG and IgG subclasses intrathecal synthesis.

Controlled trial of azathioprine and cyclosporin to prevent anti-HLA antibodies due to third-party transfusion.

The beneficial effect of elective transfusion on renal allograft survival must be weighed against the risks of sensitisation. We report a randomised controlled trial in which patients in end-stage renal failure who were non-parous and not previously transplanted or transfused, were entered in a transfusion protocol during which one group received no drugs (controls), one received azathioprine, and one received cyclosporin. Each group was given three identical transfusions of leucocyte-enriched fresh blood at 2-3 week intervals. The transfused blood was of known HLA type and donor/recipient pairs were completely mismatched. Sensitisation rates were assessed by T and B cell cross-matches between donor and recipients and by the screening of all sera against lymphocytes from 40 random donors. Fifty-one patients have completed the protocol, 20 in the control group, 12 in the azathioprine group, and 19 in the cyclosporin group. The sensitisation rate in the control group was 30%, occasionally of high titre, and persistent. In the azathioprine group, 25% developed anti-HLA antibodies and reactivity was of high titre and was broadly specific. Sensitisation in the cyclosporin group was 10%, was narrowly specific, reacting with only 10% of a panel, and was transient. There was no difference in graft survival between the groups. We conclude that cyclosporin therapy concurrent with third-party transfusion reduces the incidence, titre, and duration of sensitisation.

Twenty years of heart transplantation at Groote Schuur Hospital.

Between December 1967 and July 1987, 110 heart transplantations (61 heterotopic and 49 orthotopic) and 12 heart-lung transplantations were done at Groote Schuur Hospital in Cape Town, South Africa. Twelve procedures were retransplantations, including two third interventions. The patients were divided into three groups: Group A (n = 55) from 1967 to 1982 received so-called conventional treatment of azathioprine, methylprednisolone, and antithymocyte globulin. Group B (n = 15) from 1983 to 1984 had cyclosporine in high dosages together with methylprednisolone. Group C (n = 30) received quadruple drug therapy of low-dosage cyclosporine, together with azathioprine, methylprednisolone in lower dosages, and antithymocyte globulin (for the first 4 to 6 days and rescue antithymocyte globulin for severe rejection). From Group A, nine of 55 patients are alive up to 17 years after transplantation. The main causes of death were acute rejections and infections (in 60% altogether). From group B, six of 15 patients are alive. Acute rejections and infections were the causes of death in 12% of the patients, but multiple organ failure was a major cause in 24% most probably because of the high dosages of cyclosporine. From group C, 23 of 30 patients have survived. In this group the results after heterotopic heart transplantation do not differ significantly from orthotopic transplantation, which justifies this procedure in particular situations. If all heterotopic and orthotopic transplantations are compared, orthotopic procedures have a substantially better outcome. With the modified immunosuppressive regimen (group C) combined with precise donor and recipient selection and more sophisticated rejection monitoring, the actuarial survival rate within the last 12 months is 94%.