Preemptive therapy versus universal prophylaxis with ganciclovir for cytomegalovirus in solid organ transplant recipients

Cytomegalovirus infection risk with alemtuzumab therapy in hematological malignancies: a retrospective cohort study in the non-transplant setting

Alemtuzumab is a potent lymphocyte-depleting immunotherapy used in solid organ transplan-tation (SOT), that is increasingly being applied in diverse lymphoproliferative disorders (LPDs). However, a significant toxicity limiting expanded usage is cytomegalovirus (CMV) infection, for which standardized preventive strategies exist in SOT but not in LPDs due to a poor understanding of infection risk in this population, with early LPD studies largely limited to stem cell transplantation. Using one of the most diverse arrays of LPDs studied to date, our retrospective cohort study of non-transplant patients receiving alemtuzumab over a ten-year period at a large regional cancer center examines the incidence and clinical profile of infected patients. Among 24 patients, we identified a composite CMV infection rate of 42% with a symptomatic rate of 21%. We also noted significant variations in preventive strategies, which alongside a high infection rate presents an opportunity to improve outcomes through further work in standardization.

Innate and adaptive effector immune drivers of cytomegalovirus disease in lung transplantation: a double-edged sword

Up to 90% of the global population has been infected with cytomegalovirus (CMV), a herpesvirus that remains latent for the lifetime of the host and drives immune dysregulation. CMV is a critical risk factor for poor outcomes after solid organ transplant, though lung transplant recipients (LTR) carry the highest risk of CMV infection, and CMV-associated comorbidities compared to recipients of other solid organ transplants. Despite potent antivirals, CMV remains a significant driver of chronic lung allograft dysfunction (CLAD), re-transplantation, and death. Moreover, the extended utilization of CMV antiviral prophylaxis is not without adverse effects, often necessitating treatment discontinuation. Thus, there is a critical need to understand the immune response to CMV after lung transplantation. This review identifies key elements of each arm of the CMV immune response and highlights implications for lung allograft tolerance and injury. Specific attention is paid to cellular subsets of adaptive and innate immune cells that are important in the lung during CMV infection and reactivation. The concept of heterologous immune responses is reviewed in depth, including how they form and how they may drive tissue- and allograft-specific immunity. Other important objectives of this review are to detail the emerging role of NK cells in CMV-related outcomes, in addition to discussing perturbations in CMV immune function stemming from pre-existing lung disease. Finally, this review identifies potential mechanisms whereby CMV-directed treatments may alter the cellular immune response within the allograft.

Low-Dose vs Standard-Dose Valganciclovir for Cytomegalovirus Prophylaxis After Kidney Transplantation: A Single-Center Retrospective Analysis

BACKGROUND

Prophylactic administration of valganciclovir (VG) is an accepted method for the prevention of cytomegalovirus (CMV) infection after kidney transplantation (KTx). The standard dosage of oral VG is 900 mg/day, adjusted to renal function. There is growing evidence that low-dose 450 mg/day VG might be safe and effective. We compared low-dose vs standard-dose prophylaxis after KTx in a single-center follow-up study.

METHODS

Data from 603 renal transplantations at a single center were retrospectively analyzed (2011-2014, 12-month follow-up). Recipients with donor IgG positive-recipient IgG positive (D+/R+), (D+/R-), and (D-/R+) CMV serostatus were routinely treated with 450 mg/day VG for 3 months. Based on the same prophylactic dose, patients could be categorized into two groups according to their postoperative renal function: those receiving standard-dose VG due to a lower estimated glomerular filtration rate (eGFR) (average eGFR<60 mL/min/1.73 m2) and those receiving low-dose VG due to higher eGFR (average eGFR>60 mL/min/1.73 m2).

RESULTS

Estimated glomerular filtration rate-based VG serum alterations significantly affected the risk of CMV infection with a higher incidence in higher VG levels (standard-dose: 357 patients, CMV: 33 cases (9.2 %); low-dose: 246 patients, CMV: 10 cases (4.1%). The occurrence of known risk factors: serologic risk distribution and rate of induction therapy were not statistically different between the 2 groups. Treatment of an acute rejection episode influenced the infection rate significantly in the standard-dose group. As a side effect of prophylaxis, leucopenia (<3G/L) was 2.46 times higher in standard-dose vs low-dose group.

CONCLUSION

Low-dose VG administration is safe and non-inferior to the standard dose in the prophylaxis of CMV infection after KTx.

Prevention and management of human cytomegalovirus in pediatric HSCT recipients: A review

Cytomegalovirus (CMV), like other herpesviruses, has the unique ability to establish latent infection with subsequent reactivation during periods of stress and immunosuppression. Herpesviruses cause potentially devastating disease, particularly in hematopoietic stem cell transplant (HSCT) recipients. CMV is especially of concern in HSCT recipients given the high community seroprevalence, high risk of reactivation and high risk of transmission from HSCT donors to recipients causing primary infection after transplantation. The risk of CMV infection and severity of CMV disease varies depending on the underlying disease of the HSCT recipient, donor and recipient CMV status prior to HSCT, type of conditioning therapy in preparation for HSCT, allogeneic versus autologous HSCT, donor graft source, timing of infection in relation to HSCT, and other patient comorbidities. Different strategies exist for prevention (e.g., preemptive therapy vs. universal prophylaxis) as well as management of CMV disease (e.g., antiviral therapy, augmenting immune reconstitution, cytotoxic T-cell therapy). The purpose of this narrative review is to discuss diagnosis, prevention, and management of CMV infection and disease at different stages of HSCT, including key points illustrated through presentations of complex cases and difficult clinical scenarios. Traditional and novel strategies for CMV management will be discussed in the context of these unique clinical cases.

Letermovir conversion after valganciclovir treatment in cytomegalovirus high-risk abdominal solid organ transplant recipients may promote development of cytomegalovirus-specific cell mediated immunity

PURPOSE

To evaluate the association of conversion from valganciclovir to letermovir on cytomegalovirus-specific cellular immunity.

METHODS

Adult patients were included if they received a kidney or liver transplant between 8/1/2018-12/31/20, developed symptomatic, high-level CMV viremia and were converted to letermovir 480 mg daily as monotherapy after treatment with ganciclovir-derivatives for a minimum of 4 weeks and had subsequent CMV cell-mediated immunity (CMI) testing via ICS assay by flow cytometry (Viracor Eurofins T Cell Immunity Panel).

RESULTS

Seven patients met inclusion criteria; 87.5% were male and recipients of a kidney transplant. All patients were CMV high risk (D+/R-). Mean time from transplant to CMV disease was 200 ± 91 days. Peak viral load (VL) during CMV treatment was 540,341 ± 391,211 IU/mL. Patients received a mean of 30 ± 24 weeks (range: 4-78 weeks) of therapy with ganciclovir-derivatives at induction doses prior to letermovir introduction. The median absolute lymphocyte count (ALC) at letermovir initiation was 400/μL (IQR 575) and the median VL was 51.6 (range: ND-490) IU/mL. Most patients (n = 5/7, 71.4%) experienced an increase in VL 1 and/or 2 weeks after conversion to letermovir. All patients had positive CMI per ICS assay after conversion. Patients received a mean of 10.3 ± 6.9 weeks of letermovir prior to having a positive result. Median ALC at positivity was 900/μL. Immunosuppression was not further reduced from initiation of letermovir to demonstration of CMV CMI. No patient had progressive replication or breakthrough disease while maintained on letermovir and three patients (42.9%) underwent antiviral withdrawal without recurrence at the last follow-up.

CONCLUSION

In this case series of abdominal transplant recipients with severe or persistent CMV infection, patients developed CMV-specific CMI after conversion to letermovir monotherapy. These data suggest that using letermovir in place of valganciclovir for secondary prophylaxis may address the lack of efficacy previously seen with this approach, as well as the issues that plague antiviral withdrawal with systematic monitoring. Future prospective studies are needed to evaluate this effect in a more controlled research environment with serial CMI testing to elucidate the optimal duration of letermovir when used in this way.

In-depth summary over cytomegalovirus infection in allogeneic hematopoietic stem cell transplantation recipients

In this study, we reviewed various aspects of cytomegalovirus infection, including pathophysiology, diagnosis methods, and antiviral treatments. Background: Infections continue to be a major reason of complications like high non-relapse morbidity and mortality rate after allogenic hematopoietic stem cell transplantation. Cytomegalovirus is the most common infection in immunocompromised patients or those with graft-versus-host disease. The Latent-cytomegalovirus disease could increase the risk of reactivation in allogenic hematopoietic stem cell transplantation patients and lead to profound adverse effects on transplantation outcomes. Cytomegalovirus-specific CD4 + and CD8 + T cells reconstitution is crucial for protection against the virus reactivation. Different prophylactic, pre-emptive, and therapeutic anti-viral drugs are available to prevent cytomegalovirus infection/reactivation and treat resistant infections. Conclusion: Although there has been introduced various CMV antiviral treatment strategies like antiviral drugs, Vaccination, passive immunotherapies and adoptive transfer of CMV-specific T cells, further clinical trials are required to approve current therapies.

Pharmacokinetics, Pharmacodynamics, and Therapeutic Drug Monitoring of Valganciclovir and Ganciclovir in Transplantation

Ganciclovir and valganciclovir are first choice drugs for the prevention and treatment of cytomegalovirus infection and disease in solid organ and stem cell transplant recipients. Only a few studies on the pharmacokinetics and exposure/efficacy or exposure/safety relationships of ganciclovir and valganciclovir in transplant recipients have been published so far, and there are still controversies about the exposure parameter to use for therapeutic drug monitoring (TDM). We performed an extensive literature review of the clinical pharmacokinetics data, the exposure/effect relationships in terms of efficacy and safety, and the available tools for valganciclovir and ganciclovir TDM in adults and pediatrics transplant recipients. The pharmacokinetics of ganciclovir and valganciclovir is well described in adults and children, and a high interindividual variability is commonly observed. In contrast, the drug pharmacodynamics has been poorly described in adults and barely in children. The average 24-hour area under the concentration-time curve (AUC_0-24h ) seems to be the best predictor of efficacy and toxicity. The benefit of TDM remains controversial in adult patients but should be considered in children due to higher interindividual variability and lower probability of target attainment. Several bayesian estimators based on limited sampling strategies have been developed with this aim and may be used in clinical practice for the AUC-based individual dose adjustment of ganciclovir and valganciclovir.

Efficacy and Safety According to the Dose of Valganciclovir for Cytomegalovirus Prophylaxis in Transplantation: Network Meta-analysis Using Recent Data

BACKGROUND

Valganciclovir is used to prevent posttransplant cytomegalovirus (CMV) infection among patients undergoing kidney transplant. However, the optimal dose remains controversial because continuous use decreases kidney function and can induce leukopenia. The purpose of this study was to identify the appropriate dose of valganciclovir for preventing CMV using network meta-analysis.

METHODS

We searched the Cochrane Central Register, Ovid MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health, and Web of Science databases for studies published through April 15, 2017, evaluating 900-mg and 450-mg valganciclovir. We performed direct and indirect network meta-analysis using Bayesian models and generated rankings of different doses of valganciclovir by generating a mixed-treatment comparison.

RESULTS

Twenty-three studies involving 3478 participants were included. Compared with the control group, there was no difference in the incidence of CMV infection between the low-dose (450 mg) (odds ratio [OR], 0.79; 95% confidence interval [CI], 0.50-1.40) and high-dose (900 mg) (OR, 1.0; 95% CI, 0.61-1.60) groups. Low-dose valganciclovir had the best probability (71.1%) for decreasing CMV infection. Leukopenia was significantly more common in the high-dose group than in the control group (OR, 4.3; 95% CI, 2.69-7.10) and in the low-dose group (OR, 2.9; 95% CI, 1.88-4.67), but there was no significant difference in the incidence of leukopenia between the low-dose and control groups (OR, 1.5; 95% CI, 0.99-2.20).

CONCLUSIONS

The incidence of CMV was not different based on the dose of valganciclovir, although the tendency for CMV infection was decreased at 450 mg. However, the low dose of valganciclovir significantly reduced the incidence of leukopenia.

Utility of CMV-Specific Immune Monitoring for the Management of CMV in Solid Organ Transplant Recipients: A Clinical Update

Cytomegalovirus (CMV) is one of the most important opportunistic infections in solid organ transplant (SOT) recipients. However, current techniques used to predict risk for CMV infection fall short. CMV-specific cell mediated immunity (CMI) plays an important role in protecting against CMV infection. There is evidence that assays measuring CMV-CMI might better identify SOT recipients at risk of complications from CMV compared to anti-CMV IgG, which is our current standard of care. Here, we review recently published studies that utilize CMV-CMI, at various points before and after transplantation, to help predict risk and guide the management of CMV infection following organ transplantation. The evidence supports the use of these novel assays to help identify SOT recipients at increased risk and highlights the need for larger prospective trials evaluating these modalities in this high-risk population.

Late-onset cytomegalovirus pneumonitis successfully treated by cytomegalovirus immunoglobulin in heart transplant patient with renal failure

Cytomegalovirus infection is one of the most serious pathogens affecting solid organ transplant recipients. Cytomegalovirus has been identified as a risk factor for graft rejection, cardiac allograft vasculopathy and is associated with increased morbidity and mortality. Viral clearance is not achieved in all patients despite standard antiviral therapy; therefore, there is great interest in prevention and treatment strategies, as use of specific cytomegalovirus immunoglobulin, to avoid progression to organ involvement. Dose regimen of specific cytomegalovirus immunoglobulin is not well studied, especially in cytomegalovirus disease. We present the case of late onset of tissue invasive disease, pneumonitis, in young female patient after heart transplantation with acute renal failure, successfully treated with frequent intermittent cytomegalovirus immunoglobulin followed by renal dosed ganciclovir.

Population pharmacokinetics of ganciclovir and valganciclovir in paediatric solid organ and stem cell transplant recipients

AIMS

Ganciclovir (GCV) and its prodrug valganciclovir (VGCV) are first-line agents to prevent and treat cytomegalovirus in transplant recipients. There is high pharmacokinetic (PK) interindividual variability and PK data are scarce, especially in paediatric stem cell transplant (SCT) recipients. We sought to determine the optimal GCV and VGCV dosing in transplanted children.

METHODS

We conducted a single-centre retrospective population PK (POPPK) study of IV GCV and enteral VGCV in paediatric solid organ transplant (SOT) and SCT recipients. We included children who were transplanted and had available plasma GCV concentrations, done per standard of care. POPPK analysis was performed using a nonlinear mixed effects modelling approach with NONMEM. Optimal dosing was determined based on the achievement of the surrogate efficacy target: GCV 24 h area under the concentration-time curve (AUC_0-24h ) of 40-60 mg.h.L^-1 .

RESULTS

Fifty children with a median [range] age of 7.5 years [0.5-17.4] contributed 580 PK samples. A two-compartment model with first-order absorption with a lag time and first-order elimination fit the data well. Creatinine clearance and body weight (WT) were significant covariates for GCV clearance (CL); and WT for the volumes of distribution. IV GCV 15-20 mg.kg^-1 .day^-1 divided every 12 hours achieved the highest probability of target achievement (PTA) (33.0-33.8%). Enteral VGCV 30 and 40 mg.kg^-1 .day^-1 divided every 12 hours in children 0-<6 years, and 6-18 years, respectively, achieved the highest PTA (29.1-33.0%).

CONCLUSION

This is the first POPPK model developed in children with either SOT or SCT. Concentration target achievement was low, suggesting a potential benefit for therapeutic drug monitoring to ensure optimal exposure.

Egyptian clinical practice guideline for kidney transplantation

Objective: To present the first Egyptian clinical practice guideline for kidney transplantation (KT).

Methods: A panel of multidisciplinary subspecialties related to KT prepared this document. The sources of information included updates of six international guidelines, and review of several relevant international and Egyptian publications. All statements were graded according to the strength of clinical practice recommendation and the level of evidence. All recommendations were discussed by the panel members who represented most of the licensed Egyptian centres practicing KT.

Results: Recommendations were given on preparation, surgical techniques and surgical complications of both donors and recipients. A special emphasis was made on the recipient’s journey with immunosuppression. It starts with setting the scene by covering the donor and recipient evaluations, medicolegal requirements, recipient’s protective vaccines, and risk assessment. It spans desensitisation and induction strategies to surgical approach and potential complications, options of maintenance immunosuppression, updated treatment of acute rejection and chemoprophylactic protocols. It ends with monitoring for potential complications of the recipient’s suppressed immunity and the short- and long-term complications of immunosuppressive drugs. It highlights the importance of individualisation of immunosuppression strategies consistent with pre-KT risk assessment. It emphasises the all-important role of anti-human leucocyte antigen antibodies, particularly the donor-specific antibodies (DSAs), in acute and chronic rejection, and eventual graft and patient survival. It addresses the place of DSAs across the recipient’s journey with his/her gift of life.

Conclusion: This guideline introduces the first proposed standard of good clinical practice in the field of KT in Egypt.

Abbreviations: Ab: antibody; ABMR: Ab-mediated rejection; ABO: ABO blood groups; BKV: BK polyomavirus; BMI: body mass index; BTS: British Transplantation Society; CAN: chronic allograft nephropathy; CDC: complement-dependent cytotoxicity; CKD: chronic kidney disease; CMV: cytomegalovirus; CNI: calcineurin inhibitor; CPRA: Calculated Panel Reactive Antibodies; (dn)DSA: (de novo) donor-specific antibodies; ECG: electrocardiogram; ESWL: extracorporeal shockwave lithotripsy; FCM: flow cytometry; GBM: glomerular basement membrane; GN: glomerulonephritis; HIV: human immunodeficiency virus; HLA: human leucocyte antigen; HPV: human papilloma virus; IL2-RA: interleukin-2 receptor antagonist; IVIg: intravenous immunoglobulin; KT(C)(R): kidney transplantation/transplant (candidate) (recipient); (L)(O)LDN: (laparoscopic) (open) live-donor nephrectomy; MBD: metabolic bone disease; MCS: Mean channel shift (in FCM-XM); MFI: mean fluorescence intensity; MMF: mycophenolate mofetil; mTOR(i): mammalian target of rapamycin (inhibitor); NG: ‘not graded’; PAP: Papanicolaou smear; PCN: percutaneous nephrostomy; PCNL: percutaneous nephrolithotomy; PKTU: post-KT urolithiasis; PLEX: plasma exchange; PRA: panel reactive antibodies; PSI: proliferation signal inhibitor; PTA: percutaneous transluminal angioplasty; RAS: renal artery stenosis; RAT: renal artery thrombosis;:rATG: rabbit anti-thymocyte globulin; RCT: randomised controlled trial; RIS: Relative MFI Score; RVT: renal vein thrombosis; TB: tuberculosis; TCMR: T-cell-mediated rejection; URS: ureterorenoscopy; (CD)US: (colour Doppler) ultrasonography; VCUG: voiding cystourethrogram; XM: cross match; ZN: Ziehl–Neelsen stain

Population Pharmacokinetics and Bayesian Estimation of the Area Under the Concentration-Time Curve for Ganciclovir in Adult Chinese Renal Allograft Recipients After Valganciclovir Administration

Valganciclovir (VGCV) is the prodrug of ganciclovir (GCV). The objective of this study was to establish a population pharmacokinetic model (PPK) of GCV to investigate the PK characteristics of GCV after administration of VGCV in adult Chinese renal allograft recipients. Seventy Chinese renal allograft recipients were given 450 mg (n = 41) or 900 mg (n = 29) VGCV daily. Blood samples were drawn 0-24 hours after 5 days' therapy, and GCV plasma levels were determined. The PPK model was constructed using nonlinear mixed-effects modeling, and the Bayesian estimation of AUC_0-24h was constructed for an individual patient based on limited plasma samples. The PK of GCV was best described by a 2-compartment model with a first-order absorption process. The CL/F, V₂ /F, Q/F, V₃ /F, K_a , and lag time of GCV were 15.8 ± 0.71 L/h, 10.9 ± 2.38 L, 3.98 ± 0.40 L/h, 167 ± 44.0 L, 0.23 ± 0.0078 1/h, and 0.93 ± 0.017 hours, respectively. Clearance of creatinine was found to have a significant impact on the CL/F of GCV (P < .01). Sampling strategies consisted of plasma concentrations 0 and 2 and 0, 2, and 4 hours after VGCV administration were shown to be suitable for the estimation of the GCV AUC_0-24h . The PPK model was acceptable and can describe the PK of GCV in Chinese renal transplant patients administered VGCV. The AUC_0-24h of GCV in Chinese renal transplant patients can be calculated by a limited sampling strategy method.

Prospective Assessment of Cytomegalovirus Immunity in High-Risk Donor-Seropositive/Recipient-Seronegative Liver Transplant Recipients Receiving Either Preemptive Therapy or Antiviral Prophylaxis

The differential impact of preemptive therapy (PET) and antiviral prophylaxis (AP) on development of cytomegalovirus (CMV)-specific neutralizing antibody (nAb) and T-cell responses have not previously been directly compared in high-risk donor-seropositive/recipient-seronegative (D+R-) organ transplant recipients. We prospectively assessed T-cell and nAb responses 3 months after transplantation in cohorts of high-risk D+R- liver transplant recipients who received either PET (n = 15) or AP (n = 25) and a control group of CMV-seropositive transplant recipients (R+) (AP; n = 24). CMV phosphoprotein 65 (pp65)- and immediate early protein 1-specific multifunctional T-cell responses were determined by means of intracellular cytokine staining and nAbs against BADrUL131-Y4 CMV in adult retinal pigment epithelial cell line-19 human epithelial cells; nAbs were detected in 8 of 12 (67%) in the PET group, none of 17 in the AP group, and 20 of 22 (91%) in the R+ group. Multifunctional CD8 and CD4 T-cell responses to pp65 were generally similar between PET and R+ groups, and lower for the AP group; multifunctional CD4 responses were similar across all groups. Among D+R- liver transplant recipients, PET was associated with the development of greater nAb and multifunctional CD8 T-cell responses compared with AP, providing a potential mechanism to explain the relative protection against late-onset disease with PET. Future studies are needed to define specific immune parameters predictive of late-onset CMV disease with AP.

Global estimate of phenotypic and genotypic ganciclovir resistance in cytomegalovirus infections among HIV and organ transplant patients; A systematic review and meta-analysis

Human cytomegalovirus (CMV), an opportunistic pathogen belonging to Herpesviridae family, is considered as one of the major causes of morbidity and mortality among wide variety of patients, particularly in transplant recipients and HIV positive patients. As this virus can be resistant to treatment, frequency of CMV in patients who receive organ transplantation and people suffering from AIDS was studied between 1980 and 2019. Medline (via PubMed), Embase, Web of Science, and the Iranian Database were reviewed, and Comprehensive Meta-Analysis (V2.0, Biostat) software analyzed all data. Finally, we used Cochran's Q-statistic to encounter heterogeneity between different studies. Meta-analyses indicated, GCV resistance was 14.1% (95% CI 11.2-17.7); however, in patients suffering from AIDS and organ transplantation were 19.5% (95% CI 14.7-25.4) and 11.4% (95% CI 8.1-15.8), respectively. There were increasing rates in the prevalence of GCV resistance in CMV among transplant recipients, and HIV positive patients. Therefore, evaluation of these refractory infections is beneficial.

Safety considerations with current and emerging antiviral therapies for cytomegalovirus infection in transplantation

Introduction: Human cytomegalovirus (HCMV) is a major contributor of morbidity and mortality, and its management is essential for the successful outcome of solid organ and hematopoietic stem cell transplantation. Areas covered: This review discusses the safety profiles of currently available and emerging antiviral drugs and the other strategies for HCMV prevention and treatment after transplantation. Expert opinion: Strategies for management of HCMV rely largely on the use of antiviral agents that inhibit viral DNA polymerase (ganciclovir/valganciclovir, foscarnet, and cidofovir/brincidofovir) and viral terminase complex (letermovir), with different types and degrees of adverse effects. An investigational agent, maribavir, exerts its anti-CMV effect through UL97 inhibition, and its safety profile is under clinical evaluation. In choosing the antiviral medication to use, it is important to consider these safety profiles in addition to overall efficacy. In addition to antiviral drugs, reduction of immunosuppression is often generally needed in the management of HCMV infection, but with a potential risk of allograft rejection or graft-versus-host disease. The use of HCMV-specific or non-specific intravenous immunoglobulins remains debated, while adoptive HCMV-specific T cell therapy remains investigational, and associated with unique set of adverse effects.

Simultaneous detection of opportunistic viral infections among renal transplant patients from Sina Hospital, Tehran

Aim: A proportion of renal transplant (RT) recipients are at high risk for acquisition of opportunistic infections. Methods: A total of 101 plasma and urine specimens were collected from RT patients with raised plasma creatinine. These were tested for three common viral pathogens under suspicion of post-transplant nephropathy. Results: A total of 19 (18.8%), 15 (14.8%) and 10 (9.9%) tested positive for BK virus, cytomegalovirus and Epstein–Barr virus in their plasma and/or urine, respectively. Out of the 19 BK virus positive patients, 12 (63%) were in the tested plasma samples and 17 (89%) were in the urine samples. Four asymptomatic patients had high levels of Epstein–Barr virus shedding in their urine. No co-infected patients showed nephropathy. Conclusion: Relying on plasma creatinine rising levels alone may be an unreliable indicator for evaluating opportunistic viral infections in post-transplant RT subjects.

Late cytomegalovirus (CMV) infections after kidney transplantation under the preemptive strategy: Risk factors and clinical aspects

BACKGROUND

Late cytomegalovirus infections (LCMV) after the cessation of prophylaxis are well described. We aimed to assess clinical and epidemiological data on late-occurring cytomegalovirus (CMV) infections in the absence of CMV prophylaxis in a cohort of kidney transplant patients.

METHODS

In a cohort of kidney transplant recipients not employing CMV-specific prophylaxis, patients with CMV infections occurring after 6 months of transplantation were compared to patients with CMV infections diagnosed within the first 6 months (early infections). The main objectives were to compare clinical outcomes and evaluate risk factors for late CMV infection.

RESULTS

A total of 556 patients were evaluated. Forty-three patients with LCMV infections were compared to 513 patients with early CMV infections. LCMV infections occurred after a median of 473 days of transplantation and had a more severe course, with a statistically significant higher rate of invasive disease and graft loss (60.5% vs 21.6% and 11.6% vs 3.1% respectively). Thirty-day mortality was twice as high for patients with LCMV, but did not reach statistical significance (9.3% vs 4.3%). By multivariate analysis, employment of antilymphocyte therapy early after transplantation and tacrolimus as initial immunosuppressive therapy were significantly protective for the occurrence of LCMV infections.

CONCLUSION

Late CMV infections in the absence of specific prophylaxis after kidney transplantation have a more severe outcome when compared to early infections and occur in patients less immunosuppressed early after transplantation.

Optimal Use of Ganciclovir and Valganciclovir in Transplanted Patients: How Does It Relate to the Outcome?

Objective

Organ transplant recipients receive immunosuppressive regimens to prevent transplant rejection, which put them at increased risk for opportunistic infections like cytomegalovirus (CMV). Ganciclovir and Valganciclovir are mostly used to prevent or treat CMV. Any incorrect use of the drug may have serious consequences for patients. In this study, the outcome of transplant recipients was assessed in relation to the optimal or suboptimal use of Ganciclovir or Valganciclovir.

Methods

This study was performed on 148 hospitalized patients who received Ganciclovir or Valganciclovir in the nephrology and kidney transplantation departments of our university hospitals, from March 2012 to December 2016. Patients' demographic and clinical data including dose and duration of treatment were collected and then analyzed in comparison with the standard CMV treatment protocols.

Findings

About 94.6% of patients received Ganciclovir or Valganciclovir therapy consistent with the standard defined indications. The mean ratio of prescribed daily dose to the optimal dose was 2.9 in the first dose, 2.0 in the second dose, 1.3 in the third dose, and 1.5 in the fourth dose. From 148 included patients, 26.5% experienced CMV infection once, 7.2% experienced CMV infection twice, and 1.2% had CMV infection for 3 times, within six-month follow-up after first episode of antiviral therapy during hospitalization.

Conclusion

In this study, empiric anti-CMV therapy was initially given. The doses used were generally higher than recommended but we could not find more adverse events in the patients receiving high initial doses. In any case, it seems necessary to advocate use of standard treatment guidelines to avoid adverse outcomes.

Ganciclovir

Ganciclovir is synthetic nucleoside analog of guanine closely related to acyclovir but has greater activity against cytomegalovirus. This comprehensive profile on ganciclovir starts with a description of the drug: nomenclature, formulae, chemical structure, elemental composition, and appearance. The uses and application of the drug are explained. The methods that were used for the preparation of ganciclovir are described and their respective schemes are outlined. The methods which were used for the physical characterization of the dug are: ionization constant, solubility, X-ray powder diffraction pattern, crystal structure, melting point, and differential scanning calorimetry. The chapter contains the spectra of the drug: ultraviolet spectrum, vibrational spectrum, nuclear magnetic resonance spectra, and the mass spectrum. The compendial methods of analysis of ganciclovir include the United States Pharmacopeia methods. Other methods of analysis that were reported in the literature include: high-performance liquid chromatography alone or with mass spectrometry, electrophoresis, spectrophotometry, voltammetry, chemiluminescence, and radioimmunoassay. Biological investigation on the drug includes: pharmacokinetics, metabolism, bioavailability, and biological analysis. Reviews on the methods used for preparation or for analysis of the drug are provided. The stability of the drug in various media and storage conditions is reported. More than 240 references are listed at the end of the chapter.

Impact of electronic health record-based, pharmacist-driven valganciclovir dose optimization in solid organ transplant recipients

BACKGROUND

Prophylaxis with valganciclovir reduces the incidence of cytomegalovirus (CMV) infection following solid organ transplant (SOT). Under-dosing of valganciclovir is associated with an increased risk of CMV infection and development of ganciclovir-resistant CMV.

METHODS

An automated electronic health record (EHR)-based, pharmacist-driven program was developed to optimize dosing of valganciclovir in solid organ transplant recipients at a large transplant center. Two cohorts of kidney, pancreas-kidney, and liver transplant recipients from our center pre-implementation (April 2011-March 2012, n = 303) and post-implementation of the optimization program (September 2012-August 2013, n=263) had demographic and key outcomes data collected for 1 year post-transplant.

RESULTS

The 1-year incidence of CMV infection dropped from 56 (18.5%) to 32 (12.2%, P = .05) and the incidence of breakthrough infections on prophylaxis was cut in half (61% vs 34%, P = .03) after implementation of the dose optimization program. The hazard ratio of developing CMV was 1.64 (95% CI 1.06-2.60, P = .027) for the pre-implementation group after adjusting for potential confounders. The program also resulted in a numerical reduction in the number of ganciclovir-resistant CMV cases (2 [0.7%] pre-implementation vs 0 post-implementation).

CONCLUSIONS

An EHR-based, pharmacist-driven valganciclovir dose optimization program was associated with reduction in CMV infections.

Very-late-onset cytomegalovirus disease: a case-report and review of the literature

Background

Cytomegalovirus (CMV) infection remains one of the most common and feared complications of transplantation, justifying prophylaxis or preemptive strategies guided by donor and recipient CMV serostatus. In case of seronegative donor and recipient (D−/R−), no prophylaxis is recommended. Late-onset CMV disease is usually defined as occurring after prophylaxis discontinuation in D+/R− transplant patients.

Case presentation

We are reporting the case of a D−/R− kidney Caucasian transplant recipient presenting with CMV primoinfection 12 years after renal transplant, and discuss the role of a secondary prophylaxis so late after transplantation.

Conclusions

Primary infections leading to late-onset CMV disease in transplant patients remain rare. Recurrent disease has been described in as many as one-third of these patients. A systematic secondary prophylaxis in this particular group of patients is questionable.

Disseminated cytomegalovirus infection complicating active treatment of systemic lupus erythematosus: an emerging problem

Patients with systemic lupus erythematosus (SLE) often require immunosuppression to induce remission of active disease exacerbations. Over the past two decades, treatment modalities for this condition have emerged leading to improved morbidity from disease related outcomes. However, as a result, infection risks and patterns have changed, leading to higher rates of opportunistic infections among this population. We report four cases of cytomegalovirus (CMV) in patients with SLE who received immunosuppressive therapy, including pulse steroids, antimetabolites such as mycophenolate mofetil, and alkylating agents such as cyclophosphamide. We propose that given the rise in prevalence of CMV, there is a need for appropriate screening for this opportunistic pathogen and studies to determine the risks and benefits of prophylactic or preemptive treatment for this virus.

Cytomegalovirus infection in immunosuppressed patients after kidney transplantation

The first kidney transplantation was performed in 1951 and ever since then living donor transplantation became a more and more important solution for patients with end-stage renal disease (ESRD).

Renal transplantation is a life-saving procedure. Morbidity and mortality on waiting-lists are strongly correlated with the time of dialysis and end-stage renal disease is one of the most important causes of death; this is the reason why transplantation has to be performed as soon as possible in order to reduce the time of dialysis.

Once the transplantation is performed, a number of complications may occur in post-transplant evolution, the most important of which is rejection.

The rejection may appear through several mechanisms, but one of the most frequent causes of rejection is cytomegalovirus (CMV) infection. It is very important to have a precocious and fast diagnosis of CMV infection in order to maintain the functionality and survival of the graft. PP65 CMV antigenemia has proven its effectiveness in detecting and monitoring the CMV infection in transplanted patients.

In the laboratory of the Clinical Institute of Urology and Renal Transplantation (ICUTR) of Cluj Napoca the CMV infection is evidenced by two methods: PP65antigenemia and IgM antibody identification by chemiluminiscence.

Rapid regression of cystoid macular edema associated with cytomegalovirus retinitis in adult acute myeloid leukemia by intravitreal methotrexate combined with oral valganciclovir: A case report with comparison of binocular outcome

Cytomegalovirus (CMV) retinitis is a late complication of organ and hematopoietic stem cell transplant, the risk of which depends on the degree of immunosuppression. With the institution of preemptive ganciclovir therapy early after transplant, most patients survive episodes of life-threatening CMV infection during the early months (usually the first 3 months) after transplant and hence late onset of CMV disease, such as CMV retinitis, is being recognized more frequently. Direct involvement of the macula or optic head remains the leading cause of visual loss in patients with CMV retinitis, but there are few studies investigating the management of this condition.

Herein, we present the case of 28-year-old man who had acute myeloid leukemia and developed CMV retinitis with bilateral cystoid macular edema and optic swelling in the right eye 6 months after bone marrow transplant. He received treatment with intravitreal methotrexate in the right eye in combination with oral valganciclovir. Visual acuity improved 1 month after four weekly injections of intravitreal methotrexate 400 µg/0.1 mL. Resolved disc swelling and regression of macular edema were also observed. By comparing binocular outcome, we present our findings and discuss the possible efficacy and safety of this treatment with respect to regression of anatomical damage and improvement in visual acuity.

Clinical utility of viral load in management of cytomegalovirus infection after solid organ transplantation

The negative impact of cytomegalovirus (CMV) infection on transplant outcomes warrants efforts toward improving its prevention, diagnosis, and treatment. During the last 2 decades, significant breakthroughs in diagnostic virology have facilitated remarkable improvements in CMV disease management. During this period, CMV nucleic acid amplification testing (NAT) evolved to become one of the most commonly performed tests in clinical virology laboratories. NAT provides a means for rapid and sensitive diagnosis of CMV infection in transplant recipients. Viral quantification also introduced several principles of CMV disease management. Specifically, viral load has been utilized (i) for prognostication of CMV disease, (ii) to guide preemptive therapy, (iii) to assess the efficacy of antiviral treatment, (iv) to guide the duration of treatment, and (v) to indicate the risk of clinical relapse or antiviral drug resistance. However, there remain important limitations that require further optimization, including the interassay variability in viral load reporting, which has limited the generation of standardized viral load thresholds for various clinical indications. The recent introduction of an international reference standard should advance the major goal of uniform viral load reporting and interpretation. However, it has also become apparent that other aspects of NAT should be standardized, including sample selection, nucleic acid extraction, amplification, detection, and calibration, among others. This review article synthesizes the vast amount of information on CMV NAT and provides a timely review of the clinical utility of viral load testing in the management of CMV in solid organ transplant recipients. Current limitations are highlighted, and avenues for further research are suggested to optimize the clinical application of NAT in the management of CMV after transplantation.

Antimicrobial prophylaxis in solid-organ transplantation

Solid-organ transplantation has become a widely accepted treatment modality for end-stage diseases. With the advent of newer and more potent immunosuppressive regimens, graft survival has improved, but at the expense of an increased risk for the development of infections secondary to bacterial, fungal, viral and parasitic pathogens. Prevention of such infectious complications with effective, well-tolerated and cost-effective antimicrobials would be ideal to improve the outcome of transplant patients. Cytomegalovirus is the most common cause of viral infections. Herpes simplex virus, Varicella-zoster virus, Epstein-Barr virus and others are also significant pathogens. Fungal infections are associated with the highest mortality rates. This review summarizes the most relevant data pertaining to the current understanding of infection prevention for solid-organ transplant recipients.

Strategies for the prevention of infection after solid organ transplantation

Infection is a frequent complication of organ transplantation and is associated with significant morbidity and mortality. Preventative antimicrobial strategies are a key component of the care received by transplant patients. This review summarizes the evidence supporting anti-infective prophylaxis in this setting. Specific recommendations for the prevention of bacterial, fungal, viral and parasitic infection after transplant are made, with a focus on recent developments in the field of transplant infectious diseases.

The value of pre-emptive therapy for cytomegalovirus after liver transplantation

BACKGROUND

Cytomegalovirus (CMV) infections are among the most common infections following liver transplantation. The main preventive methods for CMV infections are universal prophylaxis and pre-emptive therapy. In our study, we adopted a pre-emptive strategy in a higth-risk group of donor CMV-positive (D+)/recipient CMV-negative (R-) casses. We investigated whether this strategy was safe and effective to prevent CMV disease.

METHODS

One hundred fifty-nine liver transplantation recipients who underwent over a 15-year period were retrospectively analyzed after follow-up for at least 6 months (mean, 63 months). Weekly quantitative polymerase chain reaction (PCR) measurements were performed to detect viral DNA. No CMV drug prophylaxis was given: antiviral CMV therapy was initiated when the PCR for CMV-DNA was >400 copies/mL.

RESULTS

Fifty-one of 159 liver transplant recipients enrolled in the study received antiviral therapy. High-risk patients (D+/R-) developed CMV infections significantly more often than D-/R- serostatus (P = .005). CMV disease was diagnosed in 12% of CMV-positive patients. Independent of serostatus in 14 cases (27.5%) virological recurrence of CMV infection occurred after primary treatment. Survival analysis showed no significant difference between patients with versus without CMV infection (P = .950). No relationship could be found between transplant rejection and CMV infection (P = .349).

CONCLUSION

Our results showed that a pre-emptive strategy to prevent CMV disease was possible, even among the serological high-risk group. Only 12% of cases with CMV infection went on to manifest CMV disease with organ involvement. Survival curves were similar among patients with versus without CMV infections.

Dynamics of cell-mediated immune responses to cytomegalovirus in pediatric transplantation recipients

CMI responses, combined with quantification of CMV DNA (DNAemia), may identify transplantation recipients at risk for invasive disease. PBMC were collected in pediatric transplantation candidates at one, three, and six months post-transplant in 10 subjects (six renal, three cardiac, one stem cell) and at single time points in eight HC and 14 children greater than one yr post-transplant (LTTx). Cells were stimulated with anti-CD3mAb or CMV pp65 peptide pools and responses assessed by IFNG enzyme-linked immunosorbent spot assay and cytokine secretion. IFNG responses to anti-CD3mAb were significantly lower pretransplant relative to HC and were further decreased at one and three months post-transplant, but recovered to levels comparable to HC by six months. Responses to pp65 among CMV-seropositive recipients followed a similar pattern but recovered by three months. CMV-seropositive LTTx and HC showed a Th1 cytokine response to pp65 stimulation. Three LTTx subjects developed CMV DNAemia; two demonstrated decreased responses to anti-CD3mAB (and pp65 in the CMV seropositive subject) at the onset of DNAemia, which recovered as DNAemia resolved. Monitoring CMI in children is feasible and may provide an adjunct biomarker to predict CMV progression and recovery.

Incidence and outcomes of ganciclovir-resistant cytomegalovirus infections in 1244 kidney transplant recipients

BACKGROUND

Cytomegalovirus (CMV) infections in kidney transplant recipients are in most cases successfully treated with oral valganciclovir (VGCV). However, in a few percent of patients, mutations in the UL 97 or UL 54 gene lead to drug resistance.

METHODS

We investigated the incidence and outcomes of ganciclovir-resistant CMV viremia in all 1244 kidney recipients transplanted at our center from 2004 through 2008. CMV DNAemia was monitored in all patients at least weekly, and patients who were positive were treated preemptively with VGCV (900 mg once daily).

RESULTS

Ganciclovir-resistant mutations were detected in 27 patients (2.2%), of which 26 occurred in the 209 CMV IgG-negative recipients receiving a CMV-positive kidney (12.5%). All had UL97 gene mutations, and none had UL54 gene mutations. Mean DNAemia half-life for the first (nonresistance) episode of CMV viremia was 3.8 ± 1.2 days. After established resistance, 25 of 27 patients had their mycophenolate mofetil dose reduced by approximately 50%, and 10 of these were also treated with intravenous foscarnet. The DNAemia half-life was 3.7 ± 1.4 days in the foscarnet-treated patients, significantly shorter than in the other 17 patients, 10.8 ± 6.7 days (P = 0.001). Time to DNAemia eradication was 30 ± 16 and 81 ± 51 days in the two groups, respectively (P = 0.001).

CONCLUSION

Use of 900 mg VGCV once daily for preemptive CMV treatment is associated with a high incidence of CMV UL97-resistance gene mutations in D+/R- patients. Foscarnet treatment rapidly and safely eradicated CMV DNAemia, and also patients who only reduced the immunosuppression and continued on VGCV treatment eventually cleared the virus.

Strategies for managing cytomegalovirus in transplant recipients

IMPORTANCE OF THE FIELD

Cytomegalovirus (CMV) is the most important pathogen that affects transplant recipients, by directly causing clinical disease and by indirectly reducing patient and allograft survival.

AREAS COVERED IN THIS REVIEW

This review provides a brief overview of the direct and indirect effects of CMV disease and the traditional and newly described factors that increase the risk of disease after transplantation. Newly acquired data in the diagnostics, prevention and treatment of CMV infection are discussed, with emphasis on guidelines for management as recently endorsed by the American Society of Transplantation and the Transplantation Society.

WHAT THE READER WILL GAIN

The reader will gain up-to-date insights into the contemporary management of CMV after solid organ transplantation. Practical aspects of its diagnosis, prevention and treatment are discussed. Emerging concerns of late-onset CMV disease and antiviral resistance are also highlighted to emphasize the need to optimize CMV-prevention strategies.

TAKE HOME MESSAGE

Prevention of CMV disease is an important goal in the management of solid organ transplant recipients. The efficacy of CMV prevention should be measured not only by the significant reduction in CMV incidence but, as importantly, by the improvement in long-term allograft and patient survival.

Impact of prophylactic versus preemptive valganciclovir on long-term renal allograft outcomes

BACKGROUND

Both prophylactic and preemptive oral valganciclovir therapy are effective for the management of cytomegalovirus (CMV) postrenal transplantation in the short term. The long-term effect of either strategy is less well defined.

METHODS

We analyzed the data on 115 adult recipients previously enrolled in a prospective randomized controlled trial of prophylaxis versus preemptive therapy for CMV. The primary outcome was a composite of freedom from acute rejection, graft loss, or death. Secondary outcomes included individual primary outcomes, posttransplant cardiovascular events, new-onset diabetes mellitus after transplantation, achievement of goal blood pressure, change in body mass index, interstitial fibrosis/tubular atrophy, and change in renal function. The analysis period was a minimum of 48-month posttransplant or a date of death or graft loss, whichever was earlier.

RESULTS

The primary outcome was similar between groups (83% prophylactic vs. 81% preemptive, P=0.754). The secondary outcomes showed similarities between the prophylactic and preemptive groups. Four patients in the prophylactic group (8%) compared with none in the preemptive group (0%) died with a functioning graft, P=0.043.

CONCLUSIONS

Within the limitations of sample size, our data suggest that either strategy for the management of CMV immediately after transplantation seems effective for patient and graft survival in the long term. CMV management is one of the many therapeutic strategies incorporated into a renal transplantation protocol, which often differs among institutions, and the decision as to which approach to use remains center- and resource-specific. The increased incidence of death in the prophylactic group requires further investigation.

The effect of cytomegalovirus antigenemia titer on the efficacy of preemptive therapy for the prevention of cytomegalovirus disease after kidney transplantation

There is some controversy regarding the exact cytomegalovirus (CMV) antigenemia titer that should be used as a guideline for preemptive anti-CMV therapy. We performed 634 consecutive kidney transplantations between January 2000 and June 2007. Preemptive therapy employed intravenous gancyclovir treatment when the CMV antigenemia titer was >or=50/4x10(5) leukocytes after kidney transplantation. The 634 recipients were allocated into 2 groups according to the peak CMV antegenemia: group A, CMV antigenemia titer<50/4x10(5) (n=550); and group B, >or=50/40x10(5) (n=84). Among the 634 recipients, 264 were positive for CMV antigenemia, and 61 developed symptomatic CMV infections. The incidence of symptomatic CMV infections in group B was significantly higher than in group A. Two cases in both groups developed tissue-proven CMV disease: group A CMV colitis and CMV nephritis, and group B, 2 cases of CMV colitis. Graft and patient survival rates in groups A and B at 5 years posttransplantation were not different. The authors concluded that a CMV antigenemia titer of >or=50/4x10(5) leukocytes can be considered an appropriate guideline for preemptive anti-CMV therapy.

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.