Symptomatic cytomegalovirus infection in renal transplant recipients given either Minnesota antilymphoblast globulin (MALG) or OKT3 for rejection prophylaxis

Epidemiology of cytomegalovirus disease in solid organ and hematopoietic stem cell transplant recipients

PURPOSE

The novel and traditional risk factors for cytomegalovirus (CMV) infection and disease in solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients, the current strategies for the prevention of CMV disease, the emerging syndrome of late-onset CMV disease, and the risk factors for antiviral drug resistance are described.

SUMMARY

The evolution of transplantation practices, the changes in the characteristics of donors and recipients, the introduction of novel immunosuppressive drugs, and the widespread use of antiviral drugs for CMV prevention have collectively influenced the natural history of CMV infection and disease in SOT and HSCT recipients. Strategies for CMV prevention with the use of antiviral drugs, whether as prophylaxis or as preemptive therapy, are effective in reducing the incidence of CMV disease in transplant recipients. However, late-onset CMV disease is now emerging as a serious problem. Donor and recipient CMV serostatus and other traditional risk factors for early-onset CMV disease appear to contribute to the occurrence of late-onset CMV disease during the first year after transplantation.

CONCLUSION

The epidemiology of CMV infection and disease has changed after transplantation. Strategies to prevent late-onset CMV disease include the prolonged use of antiviral prophylaxis, but this practice can lead to the emergence of antiviral drug resistance, which has been associated with high rates of morbidity and mortality.

Decreased Cytomegalovirus infection after antilymphocyte therapy in sirolimus-treated renal transplant patients

Cytomegalovirus (CMV) infection is highly prevalent in transplant patients, especially in those submitted to a more intense immunosuppression. We monitored CMV infection in 34 patients during 60 days after antilymphocyte therapy without CMV prophylaxis. Six patients received sirolimus and 28 received no sirolimus as immunosuppression. During 60 days of follow-up time, 24/28 (86%) patients who did not use sirolimus developed CMV infection at a mean time of 32.43+/-13.67 days after antilymphocyte treatment. In contrast, no patient on sirolimus had CMV infection during the same follow-up (p<0.001). During a further 4-month follow-up, six patients on sirolimus-free therapy had recurrence of CMV, 46.5+/-18.5 days after the first episode. During this same period, one patient receiving sirolimus had one positive cell for CMV antigenemia, 169 days after antilymphocyte therapy. In conclusion, the use of sirolimus significantly reduced the incidence of CMV infection in patients treated with antilymphocyte antibodies.

Cytomegalovirus prophylaxis with ganciclovir in kidney transplant recipients receiving induction antilymphocyte antibodies

BACKGROUND

Cytomegalovirus (CMV) is one of the serious viral infections after organ transplantation, especially in patients receiving anti-lymphocyte antibodies. Prevention of the infection using antiviral chemotherapy (ganciclovir) has gained interest in the transplant community due to the availability of quantitative methods for viral detection and monitoring.

METHODS

Forty-six CMV seropositive kidney transplant recipients were assigned to receive induction immunosuppression with anti-thymocyte globulin (ATG, Fresenius). Prophylactic intravenous ganciclovir was administered for 2 weeks at a dose of 5 mg/kg/d (adjusted to kidney function) starting from the day of surgery. Patients were monitored regularly for CMV infection or disease over 1 year posttransplant. The time to CMV manifestation, the number of antigenemia assay-positive cells, the clinical severity of infection, the incidence of acute rejection, the graft function, and the duration of hospital stay were evaluated. This group was compared to a historical matched control cohort (n = 37) transplanted earlier who did not receive prophylactic ganciclovir.

RESULT

The incidence of CMV disease was significantly less among the prophylaxis than the control group (6/46 patients [13%] vs 16/37 patients [43.2%], P = <.004). The time to develop CMV manifestations was much longer in the prophylaxis group than in the control group (median 92 vs 32 days, P </=.001).

CONCLUSION

Two weeks intravenous ganciclovir prophylaxis significantly reduced the onset and severity of CMV disease among kidney transplant recipients receiving induction with anti-lymphocyte antibodies.

Sequential cytomegalovirus antigenemia monitoring in kidney transplant patients treated with antilymphocyte antibodies

BACKGROUND

Antilymphocyte antibodies (ALA) use is related to disseminated cytomegalovirus (CMV) disease after kidney transplantation. Strict surveillance of CMV infection, preemptive antiviral treatment or concomitant ganciclovir and ALA use are proposed as an attempt to prevent related clinical complications. Our objective was to describe the pattern of CMV infection, based on sequential antigenemia detection, after ALA treatment.

PATIENTS AND METHODS

Thirty renal transplant patients were prospectively screened for CMV infection after ALA treatment. CMV antigenemia (pp65 antigen detection) was monitored twice a week in the first month and weekly until 60 days after the beginning of ALA therapy. Any positive value of antigenemia was considered CMV infection.

RESULTS

Twenty-eight (93.3%) patients were CMV positive (IgG) before transplantation. The mean duration of ALA treatment was 12.1+/-2.4 days. Positive antigenemia was detected in 24 (80%) patients, a mean of 52.5+/-15 days after transplant and 44.7+/-14 days after the beginning of ALA treatment. The median antigenemia count was 7 positive cells/300,000 neutrophils (range: 1-227). Antigenemia preceded clinical symptoms by 5.8 days (0-28 days). Eighteen (75%) of 24 positive patients received ganciclovir treatment: 8 patients (26.7%) for viral syndrome, 2 patients (33.3%) for invasive disease, and 8 patients (26.7%) as part of preemptive therapy, asymptomatic with high antigenemia values. Six pp65-positive patients with low counts were followed up until a negative result and remained asymptomatic without any specific treatment.

CONCLUSION

CMV infection was frequent after ALA treatment in this group and generally occurred late after completion of treatment. Antigenemia was a reliable tool to guide preemptive treatment in these patients, and such strategy is an alternative option compared to the prophylactic use of ganciclovir with ALA treatment.

Ganciclovir prophylaxis to prevent CMV disease in kidney recipients undergoing anti-lymphocyte globulin treatment for acute rejection

Kidney recipients (n = 51) at risk of cytomegalovirus (CMV) disease, and requiring anti-lymphocyte globulin therapy because of biopsy-proven rejection, received high-dose ganciclovir, three times a week, for a total of nine doses. CMV disease was observed in seven (14%) patients within 6 months. Six of these patients were in a group of 45 CMV-seropositive recipients, and one was in a high-risk group of CMV-seronegative recipients. High-dose intravenous ganciclovir, three times a week, seems to be an efficient, safe and easy way to prevent CMV disease in patients treated with anti-lymphocyte globulins for acute rejection.

The use of daclizumab as induction therapy in combination with tacrolimus and mycophenolate mofetil in recipients with previous transplants

Clinical trials using daclizumab as induction therapy in combination with tacrolimus (TAC) and mycophenolate mofetil (MMF) have been shown to reduce the incidence of acute rejection episodes in solid organ transplantation. In an attempt to obtain a low rejection rate we proceeded with the use of daclizumab as induction therapy, in combination with TAC and MMF for recipients with previous transplants. In this study, we analyzed patients who received previous transplants, treated with the above immunosuppressive regimen. Group A consisted of four patients with previous liver transplants, group B consisted of 16 recipients with previous kidney transplants and group C consisted of three patients with previous simultaneous pancreas-kidney transplants. All patients underwent cadaveric kidney transplants except one patient in group B, who underwent a pancreas transplant. At 12 months, patient and graft survival for all groups was 100 and 100%, respectively. Acute rejection rate was 0% for group A, 12.5% for group B, and 0% for group C. Daclizumab induction therapy is effective for patients with previous transplants and does not appear to increase the risk of acute rejection.

Polyoma viral infection in renal transplantation: the role of immunosuppressive therapy

BACKGROUND

Polyoma virus infection in renal transplant recipients has been observed with increasing frequency in recent years. Renal allograft involvement in this condition may occur as a result of primary infection or secondary to reactivation of the latent virus. Interstitial nephritis, ureteric stenosis, rise in serum creatinine and allograft function loss have been attributed to this viral infection.

METHODS

In this study we reviewed our experience with 8 patients who developed polyoma viral infection confirmed by allograft biopsy. All patients were receiving mycophenolate mofetil as part of the immunosuppression and 7 of the 8 patients were on tacrolimus. All patients have biopsy proven polyoma viral infection. The following therapeutic maneuvers were carried out following the diagnosis of polyoma viral infection: 1) stopping mycophenolate and 2) switching tacrolimus to cyclosporine or reducing the tacrolimus dose to adjust it at a lower therapeutic trough level. The clinical course and outcome of our patients were reviewed in relation to manipulation of immunosuppressive medications.

RESULTS

The incidence of this infection in our transplant program in the last 3 yr was 5.3%. Seventy-five percent of the patients had at least one rejection episode and 63% had more than one rejection episode. The main risk factor for the development of polyoma viral infection was related to the intensity of immunosuppression. The use of antirejection therapy after histological diagnosis of polyoma virus infection was not associated with improvement of renal function despite the histological appearance of acute rejection. Thus, the interstitial nephritis associated with polyoma viral infection appears to be an inflammatory response to the virus rather than acute rejection. Six out of the 8 patients stabilized renal function with reduction in immunosuppression.

CONCLUSIONS

Reduction in immunosuppression was associated with the stabilization of renal function when instituted early. However, these patients were left with a degree of allograft dysfunction and their outcome may be significantly compromised. The lack of effective antiviral therapy for polyoma virus may limit the use of newer and more potent immunosuppressive medications.

The use of intravenous tacrolimus and mycophenolate mofetil as induction and maintenance immunosuppression in simultaneous pancreas--kidney recipients with previous transplants

Clinical trials using quadruple immunosuppression that include the combination of tacrolimus (TAC) and mycophenolate mofetil (MMF) have been shown to reduce the incidence of acute rejection episodes in simultaneous pancreas-kidney (SPK) transplantation. In attempting to obtain a low rejection rate without antibody induction therapy, we proceeded with the combination of TAC intravenous (i.v.), MMF, and steroids as induction therapy and as primary immunosuppression for recipients with previous transplants. In this study, we analyzed 10 patients who received previous transplants, treated with low-dose TAC i.v. as induction therapy. Group A consisted of 6 patients with previous transplants that underwent SPK and group B consisted of four recipients with previous SPK that underwent cadaveric kidney transplants. For group A, the previous transplants were: living related kidney (LRK) followed by islet cell (IC) transplant (n=2), LRK transplant (n=1), cadaver kidney (CAD) and IC transplant (n=1), SPK (n=1), and three previous CAD kidney transplants (n=1). In group A, all six kidneys were lost due to recurrent diabetic nephropathy, IC possibly to rejection, and the pancreas due to thrombosis. In group B with previous SPK transplants, three recipients lost their kidney to chronic rejection and one to long-term use of a nephrotoxic antibiotic. Currently, in all group A and B patients, the kidney and the pancreas are functioning, although 1 patient in group A developed type 2 diabetes (normal fasting C-peptide). Two patients in group A developed three rejection episodes that responded to steroid treatment. The results indicate the TAC i.v. in combination with oral TAC, MMF, and steroids offer effective induction therapy in patients with previous transplants.

Cytomegalovirus Infection and Abdominal Pain with Mycophenolate Mofetil

Mycophenolate mofetil (MMF) is an immunosuppressive agent that exerts relatively selective antiproliferative effects on T and B lymphocytes. Efficacy has been demonstrated in large-scale randomised studies, but the use of MMF is complicated by gastrointestinal upset and is associated with an increased incidence of tissue-invasive cytomegalovirus (CMV) disease. The gastrointestinal tract is a well recognised site for invasive CMV disease, and it has therefore been hypothesised that the abdominal pain commonly seen with MMF is related to CMV infection. This has only been tested in a single small uncontrolled study, where abdominal pain was associated with the presence of CMV on endoscopic biopsy. In contrast, the toxicity profile in 85 patients with psoriasis who had received relatively high dosages of mycophenolic acid, the active moiety of MMF, for up to 13 years showed that the incidence of gastrointestinal upset fell dramatically over time. We can find little evidence that CMV disease explains the gastrointestinal adverse event profile associated with MMF, and instead support the contention that high local concentrations of MMF have a direct toxic effect on cells of the small intestine. We do not recommend any changes to current policy on CMV prophylaxis in patients receiving MMF, although we recognise that some severe gastrointestinal adverse effects may be CMV-associated. The use of trough plasma concentration monitoring, divided doses and a gradually increasing dosage schedule may be of value in limiting toxicity.

The impact of ganciclovir-resistant cytomegalovirus infection after lung transplantation

BACKGROUND

Cytomegalovirus (CMV) resistance to ganciclovir has become increasingly common in acquired immunodeficiency syndrome patients but has only rarely been reported in recipients of solid organ transplants.

METHODS

A retrospective study of ganciclovir susceptibility testing of CMV isolates recovered from lung transplant recipients was performed. Patients with CMV isolates having partial (1<IC50<3 microg/ml) or full resistance (IC50> or =3 microg/ml) to ganciclovir determined by plaque reduction assay were included in a case-control study to identify risk factors for ganciclovir resistance.

RESULTS

Between 2/91 and 5/98, 18 patients (5.2% of patients transplanted) were found to have CMV infections with some degree of ganciclovir resistance (4 partially, 14 fully resistant). More positive viral blood cultures (3.2+/-2.5 vs. 1.6+/-1.4 CMV positive cultures, P=0.02) and more episodes of CMV pneumonitis (0.24+/-0.23 vs. 0.10+/-0.17 episodes/bronchoscopy, P=0.02) occurring before the detection of resistance were seen among resistant patients than controls. Ganciclovir-resistant patients received more antithymocyte globulin during induction (70+/-44 vs. 45+/-39 mg/kg, P=0.03) and received ganciclovir for a greater number of days (79+/-52 vs. 64+/-53 days, P=0.005) before the detection of resistance than controls. Ganciclovir-resistant patients had a shorter survival and an earlier onset of bronchiolitis obliterans syndrome compared with patients in the transplant database at Washington University.

CONCLUSIONS

Ganciclovir-resistant CMV infection is a serious complication of solid organ transplantation associated with more episodes of viremia, more frequent disease, earlier onset of bronchiolitis obliterans and shorter survival. The use of antithymocyte globulin and prolonged exposure to ganciclovir are risk factors for the development of ganciclovir resistance.

A randomized prospective controlled trial of oral acyclovir versus oral ganciclovir for cytomegalovirus prophylaxis in high-risk kidney transplant recipients

BACKGROUND

Posttransplantation cytomegalovirus (CMV) infection remains a significant cause of morbidity in kidney transplant recipients. We performed a randomized prospective controlled trial of oral acyclovir versus oral ganciclovir for CMV prophylaxis in a group of renal allograft recipients considered at high risk for CMV disease due to the use of OKT3 induction therapy.

METHODS

A total of 101 recipients of cadaveric (83) and zero haplotype-matched live donor (18) kidney transplants were entered into the trial. A total of 22 D-R- patients received no prophylaxis. Twenty-seven D+R-, 29 D+R+, and 23 D-R+ patients were randomized to receive 3 months of either oral acyclovir (800 mg q.i.d.) or oral ganciclovir (1000 mg t.i.d.). Doses were adjusted according to the level of renal function. The D+R- patients were also given CMV immune globulin biweekly for 16 weeks. Surveillance blood cultures were obtained at transplantation, at months 1, 2, 3, and 6, and when clinically indicated. The primary study end points were time to CMV infection and disease the first 6 months after transplantation.

RESULTS

The mean follow up was 14.4 months. Both agents were well tolerated, and no drug interruptions for toxicity occurred. CMV was isolated in 14 of 39 (35.9%) acyclovir-treated and 1 of 40 (2.5%) ganciclovir-treated recipients by 6 months (P=0.0001). Symptomatic CMV disease occurred in 9 of 14 (64%) of the acyclovir patients, two with tissue-invasive disease. Infection rates for acyclovir vs. ganciclovir, respectively, stratified by CMV serology were: D+R-, 54 vs. 0%, P=0.0008; D+R+, 43 vs. 6.6%, P=0.01; D-R+, 8.3 vs. 0%, P=NS. No patient developed CMV infection while taking oral ganciclovir, however three delayed infections occurred 2-7 months after finishing therapy. Each patient had been previously treated for acute rejection.

CONCLUSIONS

Oral acyclovir provides effective CMV prophylaxis only for recipients of seronegative donor kidneys. Oral ganciclovir is a superior agent providing effective CMV prophylaxis for recipients of seropositive donor kidneys. Recipients who are treated for acute rejection are at risk for delayed CMV infection during the first posttransplantation year.

Cytomegalovirus and HLA-A, B, and DR locus interactions: impact on renal transplant graft survival

Graft failure rates for renal transplantations performed between 1989 and 1994 and recorded in the US Renal Data System database were retrospectively evaluated for interactions between cytomegalovirus and HLA-A, B, and DR loci. Twelve significant interactions were observed. There were significantly greater risks of graft failure for the total effect of cytomegalovirus and donor or matched HLA-DR9, recipient or matched HLA-B-51, and matched HLA-B13. We conclude that further study of renal transplants with these combinations of cytomegalovirus and HLA loci is needed to determine whether the observed interactions should be taken into consideration when matching donors with recipients.

Eradication of cytomegalovirus reactivation disease using high-dose acyclovir and targeted intravenous ganciclovir in kidney and kidney/pancreas transplantation

BACKGROUND

The attack rate of cytomegalovirus (CMV) is over 50% in solid organ transplant recipients at risk for primary CMV infection and in those receiving antilymphocyte antibody therapy. Various CMV prophylaxis regimens over the last few years have reduced the attack rate to around 20% overall.

METHODS

We report our results using high-dose acyclovir for 3 months after transplant, with targeted intravenous ganciclovir for the duration of any antilymphocyte antibody therapy, in our kidney and simultaneous pancreas/kidney transplant recipients. Records of 109 consecutive patients over a 2-year period were reviewed.

RESULTS

Six cases of CMV disease were identified. Five cases occurred in 21 patients at risk for primary CMV disease (24%), whereas only one case occurred in 73 patients at risk for CMV reactivation (1.4%).

CONCLUSION

We conclude that high-dose acyclovir and targeted ganciclovir is excellent prophylaxis against CMV reactivation in kidney and simultaneous pancreas/kidney transplantation.

A comparison of cytomegalovirus and community respiratory viruses in immunocompromised patients

Infection of organ transplant recipients with herpesviruses, especially cytomegalovirus (CMV), has been an important barrier to successful transplantation. Measures to prevent CMV infection have evolved based on the biology and epidemiology of the virus. Recently, community-acquired respiratory viruses have been recognized as an important cause of morbidity and mortality in immunocompromised hosts. It is unlikely that the strategies used to prevent and treat CMV disease will be applicable to the community respiratory viruses, owing to their different biology and epidemiology. Basic epidemiologic questions that focus on defining risk factors for disease and death from community-acquired respiratory viruses in the immunocompromised host have not been answered. The lack of established risk factors and a rapid "gold standard" diagnostic test for community-acquired respiratory viruses in the immunocompromised host has had a negative impact on the diagnosis and treatment of these infections. The study of CMV disease in organ transplant patients may serve as a blueprint for studies of community respiratory virus infections.

Muromonab CD3: a reappraisal of its pharmacology and use as prophylaxis of solid organ transplant rejection

The murine monoclonal antibody muromonab CD3 (OKT3) is directed against the CD3 antigen on peripheral human T cells and effectively blocks all T cell function. Prophylaxis with muromonab CD3 (5mg intravenously once daily for 10 to 14 days) as induction therapy together with corticosteroids, azathioprine and delayed cyclosporin (sequential therapy) optimises early graft function by delaying the potentially nephrotoxic and hepatotoxic effects of cyclosporin until graft function is established. Although clinical data are limited (by inconsistencies in trial design and trial size), prophylactic muromonab CD3-based sequential therapy is significantly more effective than standard triple therapy in the prophylaxis of allograft rejection in renal and hepatic, but not cardiac, transplant recipients. Benefits are particularly notable in patients with delayed graft function. No significant between-treatment differences in patient survival have been observed. The overall efficacy of muromonab CD3- and polyclonal-based prophylactic regimens appears to be similar, although results vary between investigators and confirmation is needed. An anti-interleukin-2 monoclonal antibody-based prophylactic regimen improved graft and patient survival compared with muromonab CD3-based prophylaxis in hepatic transplant recipients. Antimuromonab CD3 antibodies may develop; however, muromonab CD3 may be successfully reused in patients with low titres. Preliminary pharmacoeconomic data suggest that mean drug costs are greater with quadruple immunosuppressive regimens containing muromonab CD3, antithymocyte globulin (ATG) or antilymphocyte globulin (ALG) than with triple therapy. Drug costs with prophylactic muromonab CD3-based regimens were similar or greater than those with polyclonal-based protocols. The first doses of muromonab CD3 are associated with the 'cytokine-release syndrome'. More severe first-dose events include aseptic meningitis, intragraft thromboses, seizures and potentially fatal pulmonary oedema. The incidence and/or severity of cytomegalovirus infection with prophylactic muromonab CD3 based immunosuppression is similar to or greater than that with triple therapy and ATG- or ALG-based regimens. However, the risk of infection and also the observed increase in lymphoproliferative disorders appears to be related to the degree of immunosuppression rather than to the drug itself Thus, sequential muromonab CD3-based therapy is more effective than standard triple therapy (in renal and hepatic transplant recipients) and appears to be similar to that of polyclonal-based regimens in the prophylaxis of transplant rejection. Although the routine use of prophylactic muromonab CD3 in low-risk patients with primary graft function does not appear to be justified, prophylactic muromonab CD3-based therapy has a role in patients at high risk of rejection.

Failure of high-dose oral acyclovir with or without immune globulin to prevent primary cytomegalovirus disease in recipients of solid organ transplants

PURPOSE

To assess the efficacy of acyclovir and intravenous immune globulin (IVIG) for cytomegalovirus (CMV) prophylaxis in high-risk recipients of solid organ transplants.

PATIENTS AND METHODS

We randomized 21 CMV-seronegative organ transplant recipients with seropositive donors (D+R-) to receive oral acyclovir, 800 mg four times daily, or, in addition to acyclovir, IVIG, 300 mg/kg, every 2 weeks for six doses. Patients were followed closely for the development of CMV infection and disease.

RESULTS

All but one prophylactically treated patient (95%) developed CMV infection. Fifteen of 21 patients (71%) who received prophylaxis fulfilled criteria for CMV disease. Disease onset was delayed in those who received IVIG, but this did not reach statistical significance. Ganciclovir was used for treatment in 15 of the 21 patients (71%).

CONCLUSIONS

Acyclovir, with or without IVIG, did not prevent primary CMV infection or disease in D+R- solid organ transplant recipients at our institution. Moreover, most patients were treated with ganciclovir despite the use of prophylaxis. Given the ready availability of ganciclovir to treat CMV disease, we recommend a reappraisal of the role of CMV prophylaxis by these means in the solid organ transplant population.