Treatment of Cytomegalovirus Disease with Valganciclovir in Renal Transplant Recipients: A Single Center Experience

Strategies to control human cytomegalovirus infection in adult hematopoietic stem cell transplant recipients

Human cytomegalovirus (HCMV) represents the major viral complication after hematopoietic stem cell transplantation. HCMV infection may be controlled by the reconstituting immune system and remain subclinical or can lead to severe systemic and/or organ disease (mainly pneumonia and gastroenteritis) when immune reconstitution is delayed or impaired. In order to prevent the occurrence of HCMV disease, a prompt diagnosis of HCMV infection is mandatory. The adoption of pre-emptive therapy strategies guided by virological monitoring dramatically reduced the occurrence of HCMV disease. However, late-onset end-organ disease may occur in some patients with apparent immune reconstitution. In the near future, introduction of immunological monitoring and immunotherapies could markedly improve management of HCMV infection.

Impact of CMV therapy with valganciclovir on immune activation and the HIV viral load in semen and blood: an observational clinical study

BACKGROUND

The HIV RNA viral load (VL) in vaginal secretions and semen is an independent predictor of HIV transmission. Blood VL is associated with semen VL, and local mucosal factors, such as semen cytomegalovirus (CMV) reactivation, may play an important role.

METHODS

Twenty-one HIV-CMV-coinfected, antiretroviral-naive men received 900 mg of oral valganciclovir once daily for 2 weeks in an open-label study. Blood and semen were collected at baseline, after 2 weeks of valganciclovir, and 2 months after therapy completion. The primary end point was change in semen HIV levels at 2 weeks, and the secondary end points were change in semen HIV VL at 2 months and change in semen CMV levels.

RESULTS

The HIV VLs fell significantly at 2 weeks in semen (median 3.44-3.02 log10 copies/mL, P = 0.02) and blood (median 3.61-3.10 log10 copies/mL, P < 0.01) and returned to baseline after therapy completion (median 3.24 and 3.71 log10 copies/mL in semen and blood, respectively). Semen CMV levels also fell on treatment (median 2.13-1.62 log10 copies/mL, P < 0.01) and continued to fall after therapy completion (median 0.91 log10 copies/mL at week 8, P < 0.001 vs. baseline). The reduced semen CMV VL was associated with decreased semen T-cell activation and enhanced CMV-specific T-cell responses in blood; changes in the semen HIV VL were not associated with immune parameters.

CONCLUSIONS

Although valganciclovir therapy was associated with reduced HIV and semen CMV levels, these results suggest that the reduced HIV VL was a direct drug effect rather than a CMV antiviral effect or CMV-associated immune alterations.

Viral infection in renal transplant recipients

Viruses are among the most common causes of opportunistic infection after transplantation. The risk for viral infection is a function of the specific virus encountered, the intensity of immune suppression used to prevent graft rejection, and other host factors governing susceptibility. Although cytomegalovirus is the most common opportunistic pathogen seen in transplant recipients, numerous other viruses have also affected outcomes. In some cases, preventive measures such as pretransplant screening, prophylactic antiviral therapy, or posttransplant viral monitoring may limit the impact of these infections. Recent advances in laboratory monitoring and antiviral therapy have improved outcomes. Studies of viral latency, reactivation, and the cellular effects of viral infection will provide clues for future strategies in prevention and treatment of viral infections. This paper will summarize the major viral infections seen following transplant and discuss strategies for prevention and management of these potential pathogens.

Valganciclovir in the treatment of cytomegalovirus retinitis in HIV-infected patients

Oral valganciclovir is a new and highly efficacious alternative to the chronic administration of ganciclovir in the treatment of cytomegalovirus (CMV) retinitis in HIV-infected patients. In addition to its excellent bioavailability and favorable pharmacokinetic profile, valganciclovir has also proved cost effective and is the most widely used drug in the armamentarium for the treatment of CMV retinitis. Valganciclovir is a prodrug of ganciclovir, the erstwhile commonly used therapy. In March 2001, the US Food and Drug Administration approved valganciclovir for the induction and maintenance treatment of CMV disease, including CMV retinitis. Valganciclvoir has compared favorably with both oral and intravenous treatments for induction and maintenance therapy with ganciclovir. The reduced pill burden and the ease of oral administration has helped avoid the risks associated with intravenous therapy. The most serious adverse event is neutropenia, which makes the patient susceptible to infections. In the current review, we have compiled all the available evidence-based information on valganciclovir.

Immunocompromised hosts: perspectives in the treatment and prophylaxis of cytomegalovirus disease in solid-organ transplant recipients

Cytomegalovirus (CMV) infection is an important complication of solid-organ transplantation. The availability of potent antiviral therapies has decreased the incidence of CMV disease among solid-organ transplant recipients but has also led to challenges, including ganciclovir resistance, late-onset CMV disease, and uncertainty about the optimal duration of prophylaxis or therapy for CMV disease. Specific therapies and management of CMV resistance will be addressed here. The best approach for CMV disease in solid-organ transplant recipients is prevention, but which strategy--prophylaxis or preemptive therapy--is optimal remains debatable. Ganciclovir and valganciclovir remain the best options for prevention and treatment of CMV disease in solid-organ transplant recipients, but they are costly and associated with toxicity. Foscarnet and cidofovir, indicated for the treatment of patients who fail to respond to ganciclovir, are less attractive alternatives because of renal toxicity. Therefore, new therapeutic agents for CMV and an immunogenic, safe CMV vaccine are critically needed.

Management of human cytomegalovirus infection in transplant recipients by the pre-emptive therapy approach

Human cytomegalovirus (HCMV) infections are still a major infectious complication in the post-transplant period of both solid organ transplant recipients (SOTRs) and hematopoietic stem cell transplant recipients (HSCTRs). For many years, the major diagnostic assay has been antigenemia, allowing semi-quantification of HCMV load in blood from transplanted patients with disseminated HCMV infection. More recently, the real-time PCR assay has replaced antigenemia for HCMV DNAemia quantification. Prevention of HCMV disease is based on either prophylaxis or pre-emptive therapy with antiviral drugs. The latter approach has been in use in our department for the last 15 years. A cut-off of 300,000 DNA copies/ml whole blood in SOTRs with either primary or reactivated infection, and a cut-off of 10,000 DNA copies/ml blood in HSCTRs proved to be safe and effective in prospective randomized, controlled trials. With this approach, HCMV disease is consistently prevented, except for a limited number of cases of organ localization in the absence of virus in blood. In these cases, HCMV infection/disease must be diagnosed by local biopsy samples.

Viral infection after renal transplantation: surveillance and management

Viral infections remain a significant cause of morbidity and mortality following renal transplantation. Although cytomegalovirus is the most common opportunistic pathogen seen in transplant recipients, numerous other viruses have also affected outcomes. In some cases, preventive measures such as pretransplant screening, prophylactic antiviral therapy, or post transplant viral monitoring may limit the impact of these infections. Recent advances in laboratory monitoring and antiviral therapy have improved outcomes. This review will summarize the major viral infections seen following transplant and discuss strategies for prevention and management of these potential pathogens.

Update in infectious diseases in liver transplant recipients

The prevention and management of bacterial, fungal, and viral infections are important components in the care of the liver transplant recipient. Although much progress has been made, challenges still remain. This article provides updates on the management of bilomas and peritonitis, the prevention and management of invasive Candida and Aspergillus infections, the prevention and management of cytomegalovirus disease, and the current status of liver transplantation in HIV-infected patients.

Efficacy and safety of preemptive anti-CMV therapy with valganciclovir after kidney transplantation

BACKGROUND

CMV infections still pose a potentially serious threat to kidney transplant recipients and have a significant impact on graft as well as patient survival. The antiviral agent valganciclovir (VGCV) has a greater bioavailability after oral administration than oral ganciclovir (GCV) and can be considered a substitute for GCV. The substance is approved in North America and Europe for anti-CMV prophylaxis after organ transplantation. In this pilot study, we examined if VGCV could also be administered in preemptive treatment of CMV infections.

METHODS

Twenty-eight renal transplant recipients suffering from 32 asymptomatic episodes of CMV infection were treated with VGCV and followed up. CMV infection was diagnosed by routine controls of pp65-antigenemia in pre-defined intervals. All patients received sequential quadruple immunosuppression. VGCV was given for up to 12 wk in a dosage adapted to renal graft function. Efficacy and safety parameters were monitored for 16 wk.

RESULTS

Twenty-seven episodes of CMV antigenemia, two patients progressing to CMV syndrome and three patients progressing to CMV disease were treated. Primary efficiency was 79%, Four patients relapsed and were treated with a second course resulting in serological recovery. Two patients did not respond to oral VCGV and were switched to another antiviral agent. Graft function remained stable during and after treatment. Serious side effects were seen in seven patients, four patients complained of diarrhea and gastrointestinal pain, three patients suffered from leucopenia, in one of these treatment had to be temporary paused. Fifty-nine percent of all episodes were treated in a completely ambulatory setting.

CONCLUSIONS

VGCV can be considered as an option also for preemptive treatment of CMV infections after renal transplantation. The antiviral potency seems to be adequate, potential side effects are comparable with IV GCV. Because of the improved pharmacokinetics of VGCV the substance can be used to abbreviate or even completely avoid in-hospital care of CMV infections.

Efficacy of Valganciclovir in the Treatment of Cytomegalovirus Disease in Kidney and Pancreas Transplant Recipients

Cytomegalovirus (CMV) disease is relatively common following solid organ transplant, particularly if a serologically negative recipient receives an organ from a serologically positive donor (D+/R-). Although valganciclovir is approved for the treatment of CMV retinitis in AIDS patients and is used for the prophylaxis against CMV infection in solid organ transplant patients, the current standard treatment for CMV disease in solid organ transplant recipients remains intravenous ganciclovir. We retrospectively reviewed our experience using valganciclovir as treatment for CMV disease in CMV D+/R- kidney and/or pancreas transplant recipients from March 2002 to June 2005. A total of 37 cases with primary CMV disease were diagnosed and treated with either intravenous ganciclovir as induction followed with valganciclovir or valganciclovir from the beginning. We compared clinical outcomes and viremia between the two groups. Our data suggest that valganciclovir is an effective treatment modality for primary CMV disease in kidney and/or pancreas transplant recipients. It led to the resolution of disease and undetectable viremia. Valganciclovir allowed for early initiation of treatment and for treatment to be given as an outpatient. These advantages of valganciclovir have both health and economic impact for patients with CMV disease.

Valganciclovir preemptive therapy for the prevention of cytomegalovirus disease in high-risk seropositive solid-organ transplant recipients

BACKGROUND

The role of valganciclovir in the prevention of cytomegalovirus (CMV) disease in high-risk seropositive transplant patients is not known.

METHODS

We prospectively followed 301 seropositive solid organ transplant recipients to assess the efficacy and safety of valganciclovir (VGCV) in the prevention of CMV disease in high-risk patients. Asymptomatic patients with an antigenemia test >or=25 positive cells/2x10(5) polymorphonuclear cells received valganciclovir 900 mg twice a day as preemptive therapy until resolution of antigenemia (minimum 14 days). Additionally, patients treated with antilymphocytic drugs for more than 6 days received prophylaxis with VGCV 900 mg once a day during 90 days. Mean follow-up was 14 months (range 6-20 months).

RESULTS

Thirty-eight patients received VGCV; 24 as preemptive therapy and 14 due to the use of antilymphocytic drugs. No patient developed CMV disease during the follow-up. Viral load (antigenemia) decreased a mean of 78% from baseline after 7 days of VGCV therapy (P=0.024) and 98% at day 14 (P=0.029). Two patients showed a relapse of the antigenemia test >or=25 positive cells and were successfully treated with a repeated course of VGCV. Leukopenia (<2500/mm3) developed in 3/24 (12.5%) recipients in the preemptive therapy group and required to discontinuing the drug in one of them.

CONCLUSIONS

VGCV is safe and highly efficacious in the prevention of CMV disease in high-risk seropositive organ transplant recipients.

Valganciclovir: what is the status in solid organ transplantation?

Prophylactic drug therapy for cytomegalovirus disease in solid organ transplant recipients is effective and simple to implement, but it is associated with patient nonadherence and viral resistance. Recent data show that the efficacy and safety of oral ganciclovir and oral valganciclovir are similar. However, three large daily doses of oral ganciclovir are required, which is inconvenient, and viral resistance can develop to the drug. The single daily dose and lack of viral resistance are advantages of valganciclovir. This has become the primary agent for the prevention of cytomegalovirus disease. Current trials are underway to determine its effectiveness for treatment of cytomegalovirus disease, the optimal length of prophylaxis, and the safety and efficacy of a syrup formulation in children.

Cytomegalovirus infection with multiple colonic perforations in a renal transplant recipient

Cytomegalovirus (CMV) continues to be potentially the most important pathogen affecting organ transplant recipients. Severe gastrointestinal complications have been reported to occur in about 10% of renal transplant recipients, sometimes with dramatic presentations. We report the case of a 57-year-old CMV-seropositive woman with end-stage renal failure who developed CMV-related colonic multiple perforation 30 days after cadaveric CMV-positive renal transplantation. CMV pp65 antigenemia test and CMV-PCR had always been negative on all the weekly controls routinely performed in the postoperative period. Only after the sudden onset of this complication did the antigenemia and PCR become positive. The relationship between infection and perforation has been established beyond any doubt, as the histology of the resected colonic segment revealed florid CMV infection with evidence of typical inclusions in both macrophages and endothelial cells. Colonic perforations are often fatal in transplant recipients because of inability to contain the perforation, and only a rapid diagnosis and an aggressive surgical treatment can improve the prognosis.

Comparison of Quantitative PCR and Antigenemia in Cytomegalovirus Infection in Renal Transplant Recipients

Cytomegalovirus infection is a common complication of renal transplantation. Antigen pp65 levels serve as indicators of viral load, although the technique is difficult to perform and interpret. We sought to determine whether quantitative PCR had a higher sensitivity and predictive value in CMV infection.

METHODS

The study included 100 renal transplant recipients who were screened for IgM and IgG at the time of admission. On days 7, 15, 30, 45, 60, 75, 90, 120, 180, and 360, antigenemia tests were performed on blood (pp65) and urine, and a quantitative PCR on blood. Among 59 patients recruited between November 2003 and August 2004 the mean age was 54.5 +/- 12.9 years. Two patients did not reach 90 days follow-up (3%); four patients have not surpassed 90 days (7%); 22, 120 days (37%); and 31, 180 days (53%). Ninety-three percent of patients showed anti-IgG CMV-positive titers with all being IgM CMV-negative at baseline. The patients at risk for infection were given valgancyclovir as prophylaxis throughout the study.

RESULTS

At 474 visits, 8 samples (2.4%) were positive with urine; 5 (1.4%) with pp65, and 15 (4.7%) with PCR. Among the 15 positive samples, two (>100,000 and 3250 copies) revealed agreement of positive IgM and shellvial test on urine; two (15,100 and 5670 copies), antigen pp65 1+; one (17,400 copies) with pp65 2+ and shellvial urine; two (99,400 and 28,300 copies) with pp65 1+ and shellvial urine; and eight remaining determinations, 749, 2250, 686, 928, 2250, 26600, 777, and 2790 copies. The rest of the tests were negative.

CONCLUSION

The preliminary results of this study demonstrated that quantitative PCR was a useful rapid tool for diagnosing and monitoring CMV infections.

Management of cytomegalovirus infection in lung transplant recipients: evidence-based recommendations

Cytomegalovirus (CMV) continues to cause significant morbidity and mortality in lung transplant recipients. This article presents recommendations based on available evidence for the optimal management of CMV in lung transplant recipients, which have been developed by an expert committee of transplant physicians-surgeons and infectious disease specialists.

New agents for the prevention of opportunistic infections in haematopoietic stem cell transplant recipients

Over the past three decades, autologous and allogeneic haematopoietic stem cell transplants (HSCTs) have become effective treatments for a variety of malignant and nonmalignant conditions. Patients who undergo HSCT receive high doses of chemotherapy and/or radiation that induce a prolonged period of profound immunodeficiency, placing them at high risk for infection from a panoply of opportunistic organisms. Although supportive treatment for these patients has markedly improved, 10-20% of allogeneic HSCT recipients will ultimately succumb to infection. Joint guidelines to prevent opportunistic infection were released in 2000 by the Centers for Disease Control, the Infectious Diseases Society of America, and the American Society of Blood and Marrow Transplantation; however, treatment decisions for these patients are often based on limited studies or depend on institution-specific transplant protocols and antibiotic resistance patterns. This paper will discuss new agents for preventing bacterial, fungal and viral infections in HSCT recipients.

Recomendaciones GESITRA-SEIMC y RESITRA sobre prevención y tratamiento de la infección por citomegalovirus en pacientes trasplantados

Cytomegalovirus (CMV) infection remains an important complication of transplantation. The last decade has been characterized by improvements to management that has reduced its morbidity and mortality. The advance has been particularly important in the diagnosis and prevention. Several techniques have been developed that allow the increasingly rapid and sensitive diagnosis. The different preventive strategies include use of appropriate blood products, immune globulin, and antiviral agents either as prophylaxis or pre-emptive therapy. The development of effective oral drugs as valganciclovir also represents a new advance. It is necessary to summarize these advances to facilitate the development of local policies reflecting recent changes. The Group of Study of Infections in Transplantation (GESITRA) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) has therefore produced actual recommendations in the management of CMV infection after transplantation.

Treatment of Cytomegalovirus Infection or Disease in Solid Organ Transplant Recipients With Valganciclovir

Valganciclovir (VGC) has proved efficacious and safe for the prophylaxis against cytomegalovirus (CMV) in high-risk transplant recipients and for the treatment of CMV retinitis in AIDS patients. We used VGC for the treatment of CMV infection (viremia without symptoms) or disease (CMV syndrome or tissue-invasive disease) in kidney, heart, and lung transplant recipients. Fourteen transplant recipients were treated: five for asymptomatic CMV infection and nine for CMV disease. VGC was administered in doses adjusted to renal function for 4 to 12 weeks (induction and maintenance therapy). Clinically, all nine patients with CMV disease responded to treatment. Microbiologically, treatment with VGC turned blood culture negative for CMV within 2 weeks in all patients and was associated with a > or =2 log decrease in blood CMV DNA within 3 weeks in 8 of 8 tested patients. With a follow-up of 6 months (n = 12 patients), asymptomatic recurrent CMV viremia was noted in five cases, and CMV syndrome noted in one case (all cases in the first 2 months after the end of treatment). VGC was clinically well tolerated in all patients; however, laboratory abnormalities occurred in three cases (mild increase in transaminases, thrombocytopenia, and pancytopenia). This preliminary experience strongly suggests that therapy with VGC is effective against CMV in organ transplant recipients; however, the exact duration of therapy remains to be determined: a longer course may be necessary to prevent early recurrence.