Determination, validation and standardization of a CMV DNA cut-off value in plasma for preemptive treatment of CMV infection in solid organ transplant recipients at lower risk for CMV infection

A practical guide to real-world implementation of pre-emptive therapy for Cytomegalovirus disease prevention in high-risk seronegative liver transplant recipients with seropositive donors

The Comparison of Antiviral Preventative Strategies In Liver Transplant (CAPSIL) study showed pre-emptive therapy (PET) to be superior to antiviral prophylaxis for Cytomegalovirus (CMV) disease prevention in high-risk CMV seronegative liver transplant recipients (LTRs) with seropositive donors (D+R-). Despite the statistical superiority of PET over prophylaxis in research settings, PET is perceived as a logistically more complex strategy that requires careful coordination of weekly CMV PCR testing, prompt initiation of CMV antivirals upon viremia detection, and timely cessation of antivirals following viremia resolution. Transplant centers may be hesitant to use PET for CMV disease prevention in D+R- LTRs out of concern that PET coordination is not feasible in clinical practice. We recently described our experience using PET in CMV D+R- LTRs in a real-world setting, and found it to be as effective for CMV disease prevention as PET performed as part of a clinical trial. Here, we describe a systematic approach for PET implementation in real-world settings and provide practical tools to address anticipated challenges. This framework can support transplant programs in overcoming logistical barriers to PET and incorporating an evidence-based and cost-effective CMV prevention strategy into routine care for high-risk CMV D+R- LTRs.

QuantiFERON-CMV as a Predictor of CMV Events During Preemptive Therapy in CMV-seropositive Kidney Transplant Recipients

BACKGROUND

Prevention of cytomegalovirus (CMV) infection after kidney transplantation is costly and burdensome.

METHODS

Given its promising utility in risk stratification, we evaluated the use of QuantiFERON-CMV (QFCMV) and additional clinical variables in this prospective cohort study to predict the first clinically significant CMV infection (CS-CMV, ranging from asymptomatic viremia requiring treatment to CMV disease) in the first posttransplant year. A cost-effectiveness analysis for guided prevention was done.

RESULTS

One hundred adult kidney transplant recipients, CMV IgG + , were given basiliximab induction and maintained on steroid/mycophenolate/tacrolimus with weekly CMV monitoring. Thirty-nine patients developed CS-CMV infection (viral syndrome, n = 1; end-organ disease, n = 9; and asymptomatic viremia, n = 29). A nonreactive or indeterminate QFCMV result using the standard threshold around day 30 (but not before transplant) was associated with CS-CMV rates of 50% and 75%, respectively. A higher QFCMV threshold for reactivity (>1.0 IU interferon-γ/mL) outperformed the manufacturer's standard (>0.2 IU interferon-γ/mL) in predicting protection but still allowed a 16% incidence of CS-CMV. The combination of recipient age and type of donor, along with posttransplant QFCMV resulted in a prediction model that increased the negative predictive value from 84% (QFCMV alone) to 93%. QFCMV-guided preemptive therapy was of lower cost than preemptive therapy alone ( P  < 0.001, probabilistic sensitivity analysis) and was cost-effective (incremental net monetary benefit of 210 USD) assuming willingness-to-pay of 2000 USD to avoid 1 CMV disease.

CONCLUSIONS

Guided CMV prevention by the prediction model with QFCMV is cost-effective and would spare from CMV surveillance in 42% of patients with low risk for CS-CMV.

Altered Signatures of Plasma Inflammatory Proteins and Phonotypic Markers of NK Cells in Kidney Transplant Patients upon CMV Reactivation

Cytomegalovirus (CMV) reactivation remains a common opportunistic infection with a prominent role in immune reconstitution in organ transplant recipients. CMVs as important drivers of natural killer (NK) cell differentiation has been indicated to prompt several phenotypic and functional alteration in these cells. We aimed to monitor the reconstitution of NK cells and change the signature of inflammatory proteins at the critical phase of CMV reactivation over six months after kidney transplantation. The present study indicated that CMV reactivation is associated with the development of IL-6, IL-10, and cytotoxic granules, including granzyme-B and granulysin, and the drop in the frequency of CD16 + NKG2A-CD57 + NK cell subset in kidney transplant recipients (KTRs) with reactivation versus non- reactivated ones. Our findings describe distinct immune signatures that emerged with CMV reactivation after kidney transplantation, which may be helpful in the timely management of CMV infection in KTRs.

Incidence of Cytomegalovirus disease and viral replication kinetics in seropositive liver transplant recipients managed under preemptive therapy in a tertiary-care center in Mexico City: a retrospective cohort study

Background

In the absence of an adequate prevention strategy, up to 20% of CMV IgG+ liver transplant recipients (LTR) will develop CMV disease. Despite improved reporting in CMV-DNAemia, there is no consensus as to what the ideal CMV-DNAemia cutoff for a successful preemptive strategy is. Each transplant centre establishes their own threshold. We aimed to determine the effectiveness of our preventive strategy in CMV IgG+ LTR, and evaluate CMV replication kinetics.

Methods

In this retrospective study we determined the incidence of CMV disease in the first 6 months following transplantation in CMV seropositive LTR in a tertiary-care centre in Mexico. Secondary outcomes were determining the number of patients who required preemptive therapy (treatment cutoff ≥ 4000 UI/ml), adherence to the centre’s prevention protocol and calculation of viral replication kinetics.

Results

One-hundred and twenty-four patients met inclusion criteria. Four patients (3.2%) developed CMV disease. Ninety-six (85%) had detectable DNAemia and 25 (22%) asymptomatic patients received preemptive therapy, none of them developed CMV disease. The highest viral loads were observed on the second posttransplant month. The number of viral load measurements decreased over time. Patients with DNAemia ≥ 4000 UI/ml had a faster viral load growth rate, shorter viral load duplication time, and higher basic reproductive number. Viral load growth rate and autoimmune hepatitis were associated with development of DNAemia ≥ 4000 UI/ml.

Conclusion

Cytomegalovirus disease occurred in 3.2% of the study subjects. Preemptive therapy using a threshold of CMV ≥ 4000 UI/ml was effective in reducing the incidence of end-organ disease. The viral replication parameters described in this population highlight the importance of frequent monitoring, a challenging feat for transplant programs in low- and middle-income countries.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07123-w.

Post-Liver Transplant Cytomegalovirus (CMV) Reactivation, Graft, and Patient Survival Rates in Iranian Population

Background: Human cytomegalovirus (CMV) is the major complication of viral infection in immunocompromised patients. This opportunistic infection is associated with high morbidity and mortality in transplanted recipients. Objectives: The present study aimed to determine CMV burden and assess the clinical outcome in the liver recipients with CMV reactivated infection at Nemazi Hospital, Shiraz, Iran. Methods: This retrospective study examined 657 patients who underwent liver transplantation during 2014 - 2017 to identify the CMV infection, morbidity, and mortality rates. To this end, the medical records of such patients were reviewed, and their rejection/survival rates were analyzed. Accordingly, the CMV infection was diagnosed by Taq-Man real-time PCR assays. Results: In this study, 151 (23%) had CMV reactivation at least one year after liver transplantation. Viremic patients had a viral burden between 300 - 738790 copies/mL. In this study, 41 persons (6.2%) died, and 58 liver transplant patients (8.8%) had rejection experience up to one year after their operation. Among the 41 dead patients, 21 and 20 cases were with and without CMV-reactivation, respectively. The results demonstrated that the mortality rate was significantly higher in the CMV-infected patients than the non-CMV-infected counterparts. In contrast, the graft survival rate was not significantly different between the two groups (P ≤ 0.05). Conclusions: In the present study, CMV infection can serve as a significant mortality predictor in LT patients.

Role of highly sensitive nucleic acid amplification testing for plasma cytomegalovirus DNA load in diagnosis of cytomegalovirus gastrointestinal disease among kidney transplant recipients

BACKGROUND

High plasma cytomegalovirus (CMV) DNA load is generally associated with CMV tissue-invasive disease in solid organ transplant recipients. However, some tissue-invasive diseases, especially CMV gastrointestinal (GI) disease, have undetectable to very low plasma CMV DNA loads. Highly sensitive nucleic acid amplification testing (NAAT) has been increasingly used to quantify low-level CMV DNA loads. Our primary objective was to investigate the epidemiology of CMV GI disease and evaluate the validity of plasma CMV NAAT for the diagnosis of CMV GI disease in kidney transplant (KT) recipients.

METHODS

We conducted a retrospective study of all KT recipients who developed CMV GI disease from January 2016 to December 2018. Plasma CMV DNA load was measured using real-time PCR. The cut-off value of plasma CMV DNA load for diagnosing and risk factors of CMV GI disease were analyzed.

RESULTS

A total 17 (3.4%) cases of CMV GI disease occurred in 494 KT recipients. Fifteen (88%) patients had CMV D ⁺ /R ⁺ serostatus. Fourteen (82%) patients developed CMV GI disease within 6 months after KT. Plasma CMV DNA loads were detectable in all (100%) patients with a median load 11,102 (IQR 2,935-107,160) IU/ml. A plasma CMV DNA load of 4,063 IU/ml was established as al cut-off for diagnosing CMV GI disease (AUC 0.74, sensitivity 76.5%, specificity 70%, PPV 68, NPV 78). In multivariate analysis, prolonged cold ischemic time (HR 1.14, 95% CI 1.05-1.23, P = .002) and CMV D ⁺ /R ^- serostatus (HR 9.31, 95% CI 2.12-40.74, P = .003) were associated with CMV GI disease.

CONCLUSIONS

Using highly sensitive NAAT could potentially assist in the diagnosis of CMV GI disease in a CMV D ⁺ /R ⁺ serostatus setting. KT recipients with CMV seromismatch and prolonged cold ischemic time are at higher risk of CMV GI disease.

Clinical validation of an in-house quantitative real time PCR assay for cytomegalovirus infection using the 1st WHO International Standard in kidney transplant patients

Introduction:

Cytomegalovirus (CMV) is one of the most common agents of infection in solid organ transplant patients, with significant morbidity and mortality.

Objective:

This study aimed to establish a threshold for initiation of preemptive treatment. In addition, the study compared the performance of antigenemia with qPCR results.

Study design:

This was a prospective cohort study conducted in 2017 in a single kidney transplant center in Brazil. Clinical validation was performed by comparing in-house qPCR results, against standard of care at that time (Pp65 CMV Antigenemia). ROC curve analysis was performed to determine the ideal threshold for initiation of preemptive therapy based on the qPCR test results.

Results:

Two hundred and thirty two samples from 30 patients were tested with both antigenemia and qPCR, from which 163 (70.26%) were concordant (Kappa coefficient: 0.435, p<0.001; Spearman correlation: 0.663). PCR allowed for early diagnoses. The median number of days for the first positive result was 50 (range, 24-105) for antigenemia and 42 (range, 24-74) for qPCR (p<0.001). ROC curve analysis revealed that at a threshold of 3,430 IU/mL (Log 3.54), qPCR had a sensitivity of 97.06% and a specificity of 74.24% (AUC 0.92617 ± 0.0185, p<0.001), in the prediction of 10 cells/10⁵ leukocytes by antigenemia and physician's decision to treat.

Conclusions:

CMV Pp65 antigenemia and CMV qPCR showed fair agreement and a moderate correlation in this study. The in-house qPCR was revealed to be an accurate method to determine CMV DNAemia in kidney transplant patients, resulting in positive results weeks before antigenemia.

Bimonthly viral monitoring for late-onset cytomegalovirus infection in kidney transplant recipients

Kidney transplant recipients with high-risk cytomegalovirus (CMV) serostatus (seropositive donor to seronegative recipient) are at risk for late-onset CMV after cessation of antiviral prophylaxis. We report findings from a strategy of bimonthly (every 2 weeks) CMV screening for late-onset CMV. This is a single-center retrospective cohort study of 70 high-risk CMV kidney transplant recipients transplanted between June 2016 and September 2018. Patients were monitored at 6-12 months post-transplantation for late-onset CMV using bimonthly CMV nucleic acid testing (NAT). Adherence to screening and its correlation with CMV-related hospitalizations were assessed. Failure to prevent CMV-related hospitalization was classified into three categories (non-adherence to CMV testing, rapid CMV progression, and health system failure). Twenty-one (30%) patients developed CMV DNAemia, of whom 10 (14%) required hospitalization. Reasons for CMV-related hospitalization despite screening were (i) screening non-adherence (50%), (ii) rapid progression (40%), and (iii) health system failure (10%). Adherence to screening was associated with lower viral counts at diagnosis (r = -.44, p = .049) and a trend towards lower risk of CMV-related hospitalization (OR: 0.97 per 1% increase in adherence; 95% CI: 0.94-1.00; p = .06). Bimonthly monitoring for late-onset CMV allows for early CMV detection and may lower CMV-related hospitalization.

Post-transplant absolute lymphocyte count predicts early cytomegalovirus infection after heart transplantation

Immunosuppressive therapy can decrease rejection episodes and increase the risk of severe and fatal infections in heart transplantation (HT) recipients. Immunosuppressive therapy can also decrease the absolute lymphocyte count (ALC), but the relationship between early post-transplant ALC and early cytomegalovirus (CMV) infection is largely unknown, especially in HT. We retrospectively analyzed 58 HT recipients who tested positive for CMV IgG antibody and received basiliximab induction therapy. We collected preoperative and 2-month postoperative data on ALC and CMV load. The CMV load > 1200 IU/mL was used as the cutoff value to define early CMV infection. Post-transplant lymphopenia was defined as an ALC of < 500 cells/μL at postoperative day (POD) #7. On POD #7, 29 (50.0%) patients had post-transplant lymphopenia and 29 (50.0%) patients did not. The incidence of CMV infection within 1 or 2 months of HT was higher in the post-transplant lymphopenia group than in the non-lymphopenia group (82.8% vs. 48.3%, P = 0.013; 89.7% vs. 65.5%, P = 0.028, respectively). ALC < 500 cells/μL on POD #7 was an independent risk factor for early CMV infection within 1 month of HT (odds ratio, 4.14; 95% confidence interval, 1.16-14.77; P = 0.029). A low ALC after HT was associated with a high risk of early CMV infection. Post-transplant ALC monitoring is simple and inexpensive and can help identify patients at high risk of early CMV infection.

A Comparison of Different Valgancyclovir Formulations in the Universal 6-Month Prophylaxis Against CMV Infection in Renal Transplant Recipients: A Randomized Single-Centre Study

INTRODUCTION

Cytomegalovirus (CMV) is the most common opportunistic infective pathogen in kidney transplant recipients. Valganciclovir (VAL) is commonly used for prophylaxis, especially in high-risk recipients. Generic VAL formulations have become available, but the data about their safety and efficacy are lacking.

METHODS

Consecutive de novo kidney transplant patients were randomized to generic VAL Valganciklovir Teva® (VT group)(24 patients) or Alvanocyte® (A group), Alvogen (19 patients) or to Valcyte® (V group), Roche (23 patients) in a 18-month open-label study. Universal prophylaxis was used for 6 months after the transplantation. CMV DNA levels were measured at 1,3,6,9,12 and 18 months after the transplantation. All positive measurements of CMV DNA were recorded.

RESULTS

Groups did not differ regarding the clinical characteristics or the risk for developing CMV infection in the post-transplant period. CMV replications were most common at 9 months after the transplantation with rates of 9% for the V, 13% for the VT and 26% for the A group (p=0.26). At 12 months, positive CMV DNA was recorded in 22%, 8% and 11 % of patients taking V, VT and A, respectively (p=0.37). Rates of biopsy-proven acute rejection, adverse events, and serious adverse events were similar for all formulations. Lymphocele occurred most commonly in the V group (35%) compared to 17% in VT and 17% in the A group (p=0.23). One patient from each of the A and VT groups developed CMV disease. Additionally, they were the only two patients with CMV DNA copies above 656 IU/ml. Glomerular filtration rates were similar in all groups at all time points, while proteinuria was significantly higher at 12 months in patients who received V 0.32 g/day (0.18 - 0.42), compared to patients on VT 0.2 (0.1 - 0.2), or A 0.2 (0.2 - 0.3), p=0.04.

CONCLUSION

Valgancyclovir efficacy and safety in this limited data set is similar with early administration of V, VT and A after kidney transplantation. Additional studies aimed at elucidating the effectiveness of this treatment regimen in patients who are at high risk for developing CMV infection are necessary to draw further conclusions.

Use of Viral Load as a Surrogate Marker in Clinical Studies of Cytomegalovirus in Solid Organ Transplantation: A Systematic Review and Meta-analysis

Symptomatic cytomegalovirus (CMV) disease has been the standard endpoint for clinical trials in organ transplant recipients. Viral load may be a more relevant endpoint due to low frequency of disease. We performed a meta-analysis and systematic review of the literature. We found several lines of evidence to support the validity of viral load as an appropriate surrogate end-point, including the following: (1) viral loads in CMV disease are significantly greater than in asymptomatic viremia (odds ratio, 9.3 95% confidence interval, 4.6-19.3); (2) kinetics of viral replication are strongly associated with progression to disease; (3) pooled incidence of CMV viremia and disease is significantly lower during prophylaxis compared with the full patient follow-up period (viremia incidence: 3.2% vs 34.3%; P < .001) (disease incidence: 1.1% vs 13.0%; P < .001); (4) treatment of viremia prevented disease; and (5) viral load decline correlated with symptom resolution. Based on the analysis, we conclude that CMV load is an appropriate surrogate endpoint for CMV trials in organ transplant recipients.

A Nationwide Survey of Cytomegalovirus Prevention Strategies in Kidney Transplant Recipients in a Resource-Limited Setting

Objective

Strategies to prevent cytomegalovirus (CMV) infection in resource-limited settings have been under-explored. We investigated CMV prevention strategies utilized among transplant centers in Thailand.

Method

A questionnaire on CMV prevention strategies for kidney transplant (KT) recipients was developed using a web-based electronic survey website (www.surveymonkey.com). The survey was delivered to 31 transplant centers in Thailand. One infectious disease physician (ID) and 1 nephrologist (NP) from each center were included.

Results

There were 43 respondents from 26 of the 31 transplant centers (84%), including 26 (60%) IDs and 17 (40%) NPs. Forty-one 95% (41/43) physicians agreed on the necessity of CMV prevention. Of these, 77% (33/43) physicians implemented prevention strategies for their patients. Interventions included preemptive approaches (48%), prophylaxis (45%), hybrid approaches; surveillance after prophylaxis (3%), and CMV-specific immunity-guided approaches (3%). For CMV-seropositive KT recipients, use of preemptive approaches (84%) exceeded prophylaxis (12%). However, 81% of the former preferred targeted prophylaxis in patients receiving antithymocyte globulin therapy. Sixty-five percent and 93% of physicians started preemptive therapy when plasma CMV DNA loads reached 2000 and 3000 copies/mL (1820 and 2730 IU/mL), respectively. A significantly greater percentage of NPs initiated preemptive therapy at a plasma CMV DNA load of 1820 IU/mL compared with IDs (88% vs 50%; P = .02). The most common barrier to prevention strategy implementation was financial inaccessibility of oral valganciclovir (67%) and quantitative CMV DNA testing (12%).

Conclusions

Most physicians agreed on a need for preemptive approaches, although prophylaxis was targeted in those receiving intense immunosuppression. The financial implication is the main barrier for CMV prevention in Thailand.

The Third International Consensus Guidelines on the Management of Cytomegalovirus in Solid-organ Transplantation

Despite recent advances, cytomegalovirus (CMV) infections remain one of the most common complications affecting solid organ transplant recipients, conveying higher risks of complications, graft loss, morbidity, and mortality. Research in the field and development of prior consensus guidelines supported by The Transplantation Society has allowed a more standardized approach to CMV management. An international multidisciplinary panel of experts was convened to expand and revise evidence and expert opinion-based consensus guidelines on CMV management including prevention, treatment, diagnostics, immunology, drug resistance, and pediatric issues. Highlights include advances in molecular and immunologic diagnostics, improved understanding of diagnostic thresholds, optimized methods of prevention, advances in the use of novel antiviral therapies and certain immunosuppressive agents, and more savvy approaches to treatment resistant/refractory disease. The following report summarizes the updated recommendations.

Monitoring of cytomegalovirus infection in non-transplant pediatric acute lymphoblastic leukemia patients during chemotherapy

Cytomegalovirus (CMV) infection is a significant cause of morbidity and mortality in the posttransplant setting; however, it is increasingly recognized in pediatric leukemia during chemotherapy. This study assessed the prevalence and associated factors of CMV infection in pediatric non-transplant leukemia patients.This was a cross-sectional study of 50 pediatric acute lymphoblastic leukemia (ALL) patients receiving chemotherapy at Ramathibodi Hospital from December 2015 to December 2016. CMV viral load quantified by DNA polymerase chain reaction (PCR) was monitored in different phases of chemotherapy: enrolment, post-induction, post-consolidation, post-intensification, and maintenance.One hundred forty one blood tests were evaluated from 50 patients. Overall prevalence of CMV DNAemia (≥20 copies/mL) and high-level CMV DNAemia (≥1000 copies/mL) was 52% (26 of 50) and 16.0% (8 of 50), respectively. All patients with high-level CMV DNAemia were in the maintenance phase of chemotherapy. One patient had CMV retinitis, while the rest had no end-organ CMV diseases. Increased lymphocyte count was significantly associated with protection from high-level CMV DNAemia (odds ratio 0.997, P = .02). Receiver operating characteristic curve identified a cut-off value of 798 cells/mm of absolute lymphocyte count (ALC) as a discriminator for the presence of high-level CMV DNAemia (area under the curve 0.756, 95% CI 0.645-0.867, P = .001) with 88.9% sensitivity and 50.4% specificity.CMV infection predominantly occurred during maintenance chemotherapy. Low ALC was significantly associated with high-level CMV DNAemia. CMV infection surveillance by quantitative CMV DNA PCR during maintenance chemotherapy in patients with ALC <800 cells/mm may be considered.

Impact of pretransplant CMV-specific T-cell immune response in the control of CMV infection after solid organ transplantation: a prospective cohort study

INTRODUCTION

Although solid organ transplant (SOT) recipients with pretransplant serology for cytomegalovirus (CMV-R+) are considered at intermediate risk for CMV infection post transplantation, CMV infection remains a major cause of morbidity in this population. We prospectively characterized whether having pretransplant CMV-specific cellular immunity is independently associated with controlling infection after transplantation in R + SOT recipients.

METHODS

A prospective cohort of consecutive R + SOT recipients that received pre-emptive treatment for CMV infection was monitored after transplantation and variables were recorded during the follow-up. The cytomegalovirus-specific T-cell immune response was characterized by intracellular cytokine staining and viral loads determined using real-time PCR.

RESULTS

One hundred and thirty-five R + SOT recipients were included (67 kidney, 64 liver, four liver-kidney). Only one-third of the patients (42; 31.85%) had CMV-specific T-cell immunity (CD8⁺CD69⁺INF-γ⁺ T cells >0.25%) before transplantation. Patients with negative pretransplant immunity had more CMV infection (49, 52.7% vs. 15, 35.7%; p 0.07) and received more antiviral therapy than those with immunity (32, 34.4% vs. 6, 14.3%, p 0.016). Having CMV specific immunity was an independent factor for protection from developing viraemia ≥2000 IU/mL (OR 0.276, 95% CI 0.105-0.725, p < 0.01) and lower administration of treatment (OR 0.398, 95% CI 0.175-0.905, p 0.028). Only patients with no pretransplant CMV-specific T-cell response were diagnosed with CMV-disease (8, 8.6% vs. 0, 0%, p 0.05).

DISCUSSION

Our results show that having a pretransplant CMV specific T-cell response may be associated with a lower rate of CMV viraemia and less antiviral treatment after transplantation; however, more prospective studies are needed to confirm these findings.

The effect of anti-thymocyte globulin and everolimus on the kinetics of cytomegalovirus viral load in seropositive kidney transplant recipients without prophylaxis

BACKGROUND

The use of mTOR inhibitors is associated with lower incidence of CMV infections but its effect on viral load has not been investigated.

AIMS, MATERIALS AND METHODS

This post-hoc analysis included data from 273 CMV seropositive kidney transplant recipients randomized to receive anti-thymocyte globulin and everolimus (rAGT/TAC/EVR, n = 81), basiliximab and everolimus (BAS/TAC/EVR, n = 97) or basiliximab and mycophenolate (BAS/TAC/MPS, n = 95). All patients received tacrolimus (TAC) and corticosteroids. Preemptive CMV therapy based on weekly pp65 antigenemia test was used during the first 6 months. Blinded weekly CMV DNAemia was compared among the groups.

RESULTS

The proportion of patients with undetectable CMV DNAemia (23.4% vs 56.7% vs 22.1%, P < .001) was higher in the BAS/TAC/EVR. The median number of study visits with positive CMV DNAemia (2.0 vs 0.0 vs 4.6, rATG/EVR vs BAS/MPS, P = .354; BAS/EVR vs BAS/MPS, P < .0001; rATG/EVR vs BAS/EVR, P < .001) were lower in the BAS/TAC/EVR. The proportion of patients with positive CMV DNAemia who were not treat for CMV infection/disease based on pp65 antigenemia was higher in rATG/TAC/EVR group (74.1% vs 36.1% vs 44.2%, P < .001) but mean CMV DNAemia was comparable to BAS/TAC/EVR and lower than BAS/TAC/MPS (8536 ± 15 899 vs 7975 ± 17 935 vs 16 965 ± 37 694 copies/mL, P < .05), respectively. The proportion of patients with CMV DNAemia below 5000 copies/mL was higher in patients receiving EVR (74.1% vs 83.5% vs 50.0%, P = .000), respectively.

DISCUSSION AND CONCLUSION

These data suggest that mTOR inhibitors reduce the incidence of CMV infection by limiting CMV viral replication.

Clinical evaluation of Roche COBAS® AmpliPrep/COBAS® TaqMan® CMV test using nonplasma samples

Cytomegalovirus (CMV) infection is a leading cause of loss of hearing, vision, and mental retardation in congenitally infected children. It is also associated with complications of organ transplant and opportunistic HIV coinfection. The Roche COBAS^® AmpliPrep/COBAS^® TaqMan^® CMV test is an FDA-approved test that measures CMV DNA viral load in plasma for the diagnosis and management of patients at risk of CMV-associated diseases. Besides plasma, CMV is often found in bronchoalveolar lavage (BAL), cerebrospinal fluid (CSF), and urine. Thus, monitoring of CMV for critical care of patients in these nonplasma samples becomes necessary. The objective of this study was to conduct an analytic and clinical feasibility study of the Roche CMV test in BAL, CSF, and urine. The lower limit of detection, analytic measurement range, assay sensitivity, specificity, and precision were determined. Results of this study showed that the lower limit of detections were 50, 100, and 300 IU/mL for BAL, CSF, or urine, respectively. The analytic measurement ranges were from log₁₀ 2.48 to log₁₀ 5.48. The assay specificity was 94.4% for BAL and 100% for CSF and urine. The assay precision was all within the acceptable range. The performance of Roche test was further compared with 2 comparators including the RealTime CMV assay (Abbott Molecular) and a CMV Quantitative Polymerase Chain Reaction test (Vela Diagnostics). There was a general positive correlation between the Roche method and the Abbott or the Vela method. Overall, this study suggests that the Roche CMV test is suitable for the quantification of CMV viral load DNA in the described nonplasma samples.

Cytomegalovirus Disease After Liver Transplant-A Description of a Treatment-Resistant Case: A Case Report and Literature Review

Cytomegalovirus (CMV) infection is a common complication in solid organ transplant recipients. In patients receiving immunosuppressive treatment, CMV may lead to life-threatening organ complications or graft loss. We describe a case of 31-year-old CMV-seronegative patient who underwent liver transplant from a CMV-seropositive donor with an early acute resistant rejection of the transplanted organ followed by primary CMV infection, despite prophylaxis, and its severe organ complications. Routine treatment of acute allograft rejection through increasing the base immunosuppression and then administering methylprednisolone infusions did not yield significant therapeutic effect. This resulted in anti-thymocyte globulin and ultimately proteasome inhibitor introduction. The cholestasis remitted and liver parameters improved. But 4 weeks later the patient was admitted again due to incorrect liver function tests. Blood tests revealed high CMV viral load, and primary CMV infection was diagnosed. On diagnosis the patient was treated with ganciclovir (GCV) intravenously. As GCV resistance was suspected based on clinical premises, foscarnet (FOS) and leflunomide (LFM) were implemented with concomitant cautious immunosuppression reduction due to the history of recent graft rejection. Despite aggressive treatment introduction, viral clearance was not obtained. Ultimately the patient died due to respiratory distress resulting from lung fibrosis, most probably owing to CMV diseases with Pneumocystis jiroveci coinfection. The presented case proves the importance of strictly following the rules of prophylaxis, especially in patients with a high risk factor of CMV infection development. A quick diagnosis, implementation of appropriate treatment, and fast reaction to the lack of satisfying therapeutic effect can be the key to a successful treatment.

Impact of CMV PCR Blips in Recipients of Solid Organ and Hematopoietic Stem Cell Transplantation

Background

Viral blips reflecting polymerase chain reaction (PCR) artefacts or transient low-level replication are well described in the human immunodeficiency virus setting. However, the epidemiology of such blips in transplant recipients screened for cytomegalovirus (CMV) with PCR remains uncertain and was investigated in a cohort of solid organ and hematopoietic stem cell recipients.

Methods

Eligible recipients had known donor/recipient CMV IgG serostatus, and 3 CMV PCRs ≥. The CMV PCR triplicates (3 consecutive CMV PCRs) were defined; the first CMV PCR was always negative, and the time between the second and third samples was 7 days ≤. A positive second but negative third sample represented a blip. Odds ratio (OR) for factors associated with a triplicate being a blip was estimated by binomial regression adjusted for repeated measurements. Whether blips affected the hazard ratio (HR) for subsequent CMV infection was determined with a Cox model.

Results

851 recipients generated 3883 CMV PCR triplicates. The OR of a triplicate representing a blip decreased with increasing viral load of the second sample (vs 273 IU/mL; >273-910 IU/mL: odds ratio [OR], 0.2; 95% confidence interval [CI], 0.1-0.5; >910 IU/mL: OR, 0.08; 95% CI, 0.02-0.2; P ≤ 0.0002) and increased with intermediary-/low-risk serostatus (vs high risk) (OR, 2.8; 95% CI, 1.2-5.5; P = 0.01). Cumulative exposure to DNAemia in the CMV blips greater than 910 IU/mL indicated increased HR of subsequent CMV infection (HR, 4.6; 95% CI, 1.2-17.2; P = 0.02).

Conclusions

Cytomegalovirus blips are frequent; particularly when the viral load of the first positive PCR is < 910 IU/mL, and serostatus risk is intermediary/low. Accumulating blips suggest intermittent low-level replication. If blips are suspected, confirmation of ongoing replication before initiation of treatment is prudent.

Cyclosporine Versus Tacrolimus: Which Calcineurin Inhibitor Has Influence on Cytomegalovirus Infection in Cardiac Transplantation?

INTRODUCTION

Cytomegalovirus (CMV) infection is a relevant cause of morbidity and mortality in transplantation patients. Its major incidence is in the first year and viral replication is related to acute rejection, survival reduction, and graft vascular disease.

OBJECTIVE

This study aims to evaluate retrospectively whether a high dose of calcineurin inhibitors correlates with CMV-positive polymerase chain reaction (PCR), need for treatment, and death in cardiac transplantation patients.

METHODS

This is a case-control study including patients who underwent transplantation between 2014 and 2016. They were separated into two groups (positive or negative PCR) and evaluated for dosage serum levels of cyclosporine and tacrolimus. Patients were classified with adequate dose of immunosuppressant or high dose, and was analyzed that there was any association with those and positive CMV-PCR, need for treatment for CMV, and deaths. For statistical analysis, the Student t test was used for the quantitative variables and the Fisher's Exact Test for qualitative variables. To show CMV-free survival, the Kaplan-Meier curve was used. The level of significance was set at 5%.

RESULTS

CMV-positive PCR in the sample was 72% for a total of 50 individuals. Positive PCR correlated with a high dose of calcineurin inhibitors in a statistically significant way (P = .002), as did a high dose of cyclosporine (P = .004); however, a high dose of tacrolimus had no such association (P = .17). When a high dose was assessed with a need for treatment, the chance of needing treatment increased more than eight times (P = .024; odds ratio = 8.25; 95% CI = 1.33 to 51.26), which was different from results found with high-dose tacrolimus (P = 1.0). However, no significant association was found in relation to deaths.

CONCLUSIONS

Tacrolimus serum levels showed no association with CMV-PCR, which was different from serum cyclosporine, which showed association with CMV-PCR positivity, increasing the need for treatment approximately 8-fold, without association with death.

Kinetic of the CMV-specific T-cell immune response and CMV infection in CMV-seropositive kidney transplant recipients receiving rabbit anti-thymocyte globulin induction therapy: A pilot study

BACKGROUND

Some studies have suggested that rATG treatment may be associated with an increased incidence of CMV infection and delayed CMV immune response. However, the evidences supporting this matter are scarce. This study aims to characterize the kinetic of the CMV-specific T-cell immune response before and after rATG induction therapy and the relationship with the development of CMV infection in CMV-seropositive kidney transplant recipients.

METHODS

An observational prospective study of CMV-seropositive kidney transplant patients that received rATG induction therapy was performed. A pretransplant sample was obtained before the surgery to determine the CMV-specific immunity. CMV viral load (by PCR) and CMV-specific T-cell immune response (by flow cytometry) were determined during the follow-up at 0.5, 1, 2, 3, 6, and 12 months post transplantation.

RESULTS

A total of 23 patients were included in the study. CMV prophylaxis was administrated for a media of 90 days after transplantation. At the end of follow-up, 18 (78.3%) patients had CMV-specific immunity with a median value of 0.31% CD8⁺ CD69⁺ INF-γ⁺ T cells at a median of 16 weeks post transplantation. Five patients never acquired CMV-specific immunity. No statistically significant association between CMV infection and CMV-specific T-cell immune response (P = .086) was observed. However, patients with positive pretransplant CMV-specific immunity developed earlier immunity and achieved higher levels of CD8⁺ CD69⁺ INF-γ+ T-cell post-transplantation than patients with negative pretransplant immunity.

CONCLUSIONS

CMV-specific immune monitoring in addition to CMV-serology may be useful to stratify patient's risk of CMV infection before transplantation.

Assessment of the T-SPOT.CMV interferon-γ release assay in renal transplant recipients: A single center cohort study

Background

The measurement of CMV specific cellular immunity in organ transplant recipients could contribute additional acuity to serology based, CMV infection risk stratification, facilitating optimisation of immunosuppression and anti-viral prophylaxis.

Methods

A pilot study of renal transplant recipient (RTR’s) responses in the T-SPOT.CMV ELISPOT based assay. 108 RTR’s were recruited 3 months post-transplantation, immediately prior to the cessation of stratified anti-viral prophylaxis, used in recipients from seropositive donors. RTR’s were monitored for CMV viremia and disease. Cellular responses to peptides derived from CMV IE1 and pp65 were measured, using the T-SPOT.CMV assay.

Results

At recruitment, no CMV specific cellular immunity was detected by T-SPOT.CMV in CMV seronegative recipients (IE1 ≤ 1spot / 2.5x10⁵ PBMC’s; pp65 ≤ 3 spots / 2.5x10⁵ PBMC’s). At recruitment, CMV sero-positive recipients who made a robust response to both IE1 (>25 spots / 2.5x10⁵ PBMC’s) and pp65 (>50 spots / 2.5x10⁵ PBMC’s), were less likely to develop high level viremia than those who responded to one or neither antigen (0/28 vs 5/25; p<0.02).

Conclusions

In CMV seronegative RTR’s, CMV specific cellular immunity measured by T-SPOT.CMV was not detected prior to cessation of anti-viral prophylaxis. This differs from recent reports of CMV specific cellular immunity in a proportion of CMV seronegative RTR’s, associated with protection from CMV infection. In seropositive RTR’s, a dual response to IE1 and pp65 at recruitment, was associated with protection from subsequent viremia. This suggests that assessing the diversity of response to CMV antigens, may enhance risk stratification in this group.

Cytomegalovirus and Other β-Herpesviruses

Cytomegalovirus (CMV), human herpes virus (HHV)-6, and HHV-7 are ubiquitous β-herpesviruses that can cause opportunistic infection and disease in kidney transplant recipients. Active CMV infection and disease are associated with acute allograft failure and death, and HHV-6 and HHV-7 replication are associated with CMV disease. CMV prevention strategies are used commonly after kidney transplantation, and include prophylaxis with antiviral medications and preemptive treatment upon the detection of asymptomatic viral replication in blood. Both approaches decrease CMV disease and allograft rejection, but CMV prophylaxis is preferred for high-risk patients because it is easy to administer and may be more effective in real-world settings. CMV disease commonly occurs even with current preventive strategies, whereas HHV-6 and HHV-7 diseases are rare. The clinical manifestations of CMV, HHV-6, and HHV-7 are nonspecific, and laboratory confirmation is essential to establishing diagnoses. Although nucleic acid testing has supplanted other diagnostic modalities given its high sensitivity and specificity, histopathologic examination sometimes is necessary to identify disease definitively. Ganciclovir and valganciclovir are the treatments of choice for CMV and HHV-6, and foscarnet can be used to treat HHV-7. Treatment duration should be informed by the initial severity of disease, and subsequent clinical and virologic responses.

Cytomegalovirus viraemia and mortality in renal transplant recipients in the era of antiviral prophylaxis. Lessons from the western Australian experience

Background

Cytomegalovirus (CMV) establishes a lifelong infection that is efficiently controlled by the immune system; this infection can be reactivated in case of immunosuppression such as following solid organ transplantation. CMV viraemia has been associated with CMV disease, as well as increased mortality and allograft failure. Prophylactic antiviral medication is routinely given to renal transplant recipients, but reactivation during and following cessation of antiviral prophylaxis is known to occur. The aims of this study were to assess the incidence, timing and impact of CMV viraemia in renal transplant recipients and to determine the level of viraemia associated with adverse clinical outcomes.

Methods

Data from all adult (18 years and over) Western Australian renal transplant recipients transplanted between 1 January 2007 and 31 December 2012 were obtained from the Australia and New Zealand Dialysis and Transplant registry and were supplemented with data obtained from clinical records. Potential risk factors for detectable CMV viraemia (≥600 copies/ml) and all-cause mortality were assessed using univariable analysis and Cox Proportional Hazards Regression.

Results

There were 438 transplants performed on 435 recipients. The following factors increased the risk of CMV viraemia with viral loads ≥600 copies/ml: Donor positive/Recipient negative status; receiving a graft from a deceased donor; and receiving a graft from a donor aged 60 years and over. CMV viraemia with viral loads ≥656 copies/ml was a risk factor for death following renal transplantation, as was being aged 65 years and above at transplant, being Aboriginal and having vascular disease. Importantly 37% of the episodes of CMV viraemia with viral loads ≥656 copies/ml occurred while the patients were expected to be on CMV prophylaxis.

Conclusions

CMV viraemia (≥656 copies/ml) was associated with all-cause mortality in multivariable analysis, and CMV viraemia at ≥656 copies/ml commonly occurred during the period when renal transplant recipients were expected to be on antiviral prophylaxis. A greater vigilance in monitoring CMV levels if antiviral prophylaxis is stopped prematurely or poor patient compliance is suspected could protect some renal transplant recipients from adverse outcomes such as premature mortality.

Comparison of Standardized Cytomegalovirus (CMV) Viral Load Thresholds in Whole Blood and Plasma of Solid Organ and Hematopoietic Stem Cell Transplant Recipients with CMV Infection and Disease

Background

Quantification of cytomegalovirus (CMV) deoxyribonucleic acid (DNA) has important diagnostic, prognostic, and therapeutic implications in the management of transplant recipients. We aimed to assess a viral load in plasma and whole blood that distinguishes CMV disease from asymptomatic infection in a cohort of solid organ and hematopoietic stem cell transplantation.

Methods

We prospectively measured and compared CMV viral load in paired plasma and whole blood samples collected from transplant recipients with CMV infection and disease. Cytomegalovirus viral loads were determined by a commercially available US Food and Drug Administration-approved quantitative assay (COBAS AmpliPrep/COBAS TaqMan CMV Test [CAP/CTM CMV]) calibrated to the first World Health Organization International Standard for CMV DNA quantification.

Results

Moderate agreement of CMV viral load was observed between plasma and whole blood, with 31% of samples having discordant findings, particularly among samples with low DNA levels. Among the subset of samples where both paired samples had quantifiable levels, we observed a systematic bias that reflected higher viral load in whole blood compared with plasma. Based on receiver operating curve analysis, an initial plasma CMV viral load threshold of 1700 IU/mL in solid organ transplant recipients (sensitivity 80%, specificity 74%) and 1350 IU/mL in allogeneic hematopoietic stem cell transplant recipients (sensitivity 87%, specificity 87%) distinguished CMV disease and asymptomatic infection.

Conclusions

This study identifies standardized viral load thresholds that distinguish CMV disease from asymptomatic infection using CAP/CTM CMV assay. We propose these thresholds as potential triggers to be evaluated in prospective studies of preemptive therapy. Plasma was better than whole blood for measuring viral load using the CAP/CTM CMV assay.

The Association Between CMV Viremia or Endoscopic Features and Histopathological Characteristics of CMV Colitis in Patients with Underlying Ulcerative Colitis

BACKGROUND

Cytomegalovirus (CMV) infection has been shown to be related to severe or steroid-refractory ulcerative colitis (UC) flare-ups. The aim of this study was to evaluate the endoscopic and pathological characteristics of CMV colitis in patients with UC and to assess the predictive value of the endoscopic and pathological features of CMV colitis.

METHODS

A total of 50 consecutive UC patients with CMV infection who were admitted to Peking Union Medical College Hospital from 2010 to 2015 were enrolled in this study.

RESULTS

Twenty-five UC patients with CMV infection (50.0%) had concurrent CMV colitis. When the cutoff value was set at 1150 copies, the sensitivity and specificity of blood CMV DNAq polymerase chain reaction for predicting CMV colitis were 44.4% and 78.9%, respectively. A higher proportion of endoscopic punched-out ulcers, irregular ulcers, and cobblestone-like appearance were observed among the patients in the CMV colitis group than those in the non-CMV colitis group (52.0% versus 20.0%, 60.0% versus 16.0%, and 20.0% versus 0%, respectively, P < 0.05). The number of CMV inclusion bodies per high-power field was significantly higher in those with punch-out ulcerations (25.7% versus 60.0%, P < 0.05). A higher grade of pathological inflammation was observed in the CMV colitis group than in the control group (68.0% versus 44.0%).

CONCLUSIONS

Characteristic endoscopic features with punch-out ulcers and high CMV viremia load may be useful for predicting the presence of CMV colitis in histology. Punch-out ulcers were found to be associated with a higher number of inclusion bodies on histology, suggesting a role of targeted biopsy for endoscopist.

Cytomegalovirus infection in lung transplant recipients

INTRODUCTION

Cytomegalovirus (CMV) infection is a major cause of morbidity and mortality in solid organ transplant (SOT) patients. Lung transplant recipients are particularly at risk given the intense immunosuppression required. Areas covered: The Detailed review of the literature related to CMV infection, its direct and indirect effect on lung allograft function, as well as diagnosis, immune monitoring, treatment options and prevention strategies. Expert commentary: In lung transplant recipients, CMV infection is associated with pro-inflammatory and immune inhibitory effects that increase the risk of graft dysfunction and loss. Diagnosis of CMV infection remains challenging. Treatment options remain relatively limited.

Targeted preemptive therapy according to perceived risk of CMV infection after kidney transplantation

Background

Methods

Results

Conclusion

Comparison of Two Commercial Automated Nucleic Acid Extraction and Integrated Quantitation Real-Time PCR Platforms for the Detection of Cytomegalovirus in Plasma

Quantitation of cytomegalovirus (CMV) viral load in the transplant patients has become a standard practice for monitoring the response to antiviral therapy. The cut-off values of CMV viral load assays for preemptive therapy are different due to the various assay designs employed. To establish a sensitive and reliable diagnostic assay for preemptive therapy of CMV infection, two commercial automated platforms including m2000sp extraction system integrated the Abbott RealTime (m2000rt) and the Roche COBAS AmpliPrep for extraction integrated COBAS Taqman (CAP/CTM) were evaluated using WHO international CMV standards and 110 plasma specimens from transplant patients. The performance characteristics, correlation, and workflow of the two platforms were investigated. The Abbott RealTime assay correlated well with the Roche CAP/CTM assay (R² = 0.9379, P<0.01). The Abbott RealTime assay exhibited higher sensitivity for the detection of CMV viral load, and viral load values measured with Abbott RealTime assay were on average 0.76 log₁₀ IU/mL higher than those measured with the Roche CAP/CTM assay (P<0.0001). Workflow analysis on a small batch size at one time, using the Roche CAP/CTM platform had a shorter hands-on time than the Abbott RealTime platform. In conclusion, these two assays can provide reliable data for different purpose in a clinical virology laboratory setting.

Treatment and prevention of cytomegalovirus infection in heart and lung transplantation: an update

INTRODUCTION

Heart and lung transplantation are standard therapeutic strategies to improve survival and quality of life in selected patients with end-stage heart or lung diseases. Cytomegalovirus (CMV) is one the most clinically relevant and frequent post-transplant infectious agents, which may cause direct acute syndromes, and chronic indirect graft-related injury. Despite effective antiviral drugs being available to prevent and treat CMV infection, due to the immunosuppression burden and the specific characteristics of thoracic grafts, CMV infection remains a major clinical problem in heart and lung transplant recipients.

AREAS COVERED

We performed an extensive literature search focused on studies specifically including heart or lung transplantation, when available, or kidney transplant recipients when data on thoracic transplants were not available. We discuss the pros and cons supporting the use of currently available drugs and strategies for CMV prevention and treatment, highlighting current unmet needs.

EXPERT OPINION

While (Val)Ganciclovir remains the cornerstone of anti-CMV therapy, prolonged universal prophylaxis may expose a large number of patients to an excess of drug toxicity. Additional drugs with lower toxicity may be available in the context of anti-CMV prophylaxis, and effective CMV-risk stratification, by means of novel immune monitoring assays, which may help to customize the therapeutic approach.

A double-blinded, prospective study to define antigenemia and quantitative real-time polymerase chain reaction cutoffs to start preemptive therapy in low-risk, seropositive, renal transplanted recipients

BACKGROUND

Cytomegalovirus (CMV) disease occurs in 16% to 20% of low-risk, CMV-positive renal transplant recipients. The cutoffs for quantitative real-time polymerase chain reaction (qPCR) or phosphoprotein (pp65) antigenemia (pp65emia) for starting preemptive therapy have not been well established.

METHODS

We measured qPCR and pp65emia weekly from day 7 to day 120 after transplantation, in anti-CMV immunoglobulin G–positive donor and recipient pairs. Patients and physicians were blinded to the test results. Suspicion of CMV disease led to the order of new tests. In asymptomatic viremic patients, the highest pp65emia and qPCR values were used, whereas we considered the last value before diagnosis in those with CMV disease.

RESULTS

We collected a total of 1,481 blood samples from 102 adult patients. Seventeen patients developed CMV disease, 54 presented at least one episode of viremia that cleared spontaneously, and 31 never presented viremia. Five patients developed CMV disease after the end of the study period. The median (95% confidence interval) pp65emia and qPCR values were higher before CMV disease than during asymptomatic viremia (6 [9–82] vs. 3 [1–14] cells/10(6) cells; P<0.001 and 3,080 [1,263–15,605] vs. 258 [258–1,679] copies/mL; P=0.008, respectively). The receiver operating characteristic curve showed that pp65emia 4 cells/10(6) cells or greater showed a sensitivity and specificity to predict CMV disease of 69% and 81%, respectively (area, 0.769; P=0.001), with a positive predictive value of 37% and a negative predictive value of 93%. For qPCR 2,000 copies/mL or higher, the positive predictive value and negative predictive value were 57% and 91%, respectively (receiver operating characteristic area, 0.782; P=0.000).

CONCLUSION

With these cutoffs, both methods are appropriate for detecting CMV disease.

Cytomegalovirus infection in liver transplant recipients: Updates on clinical management

Cytomegalovirus (CMV) infection is a common complication after liver transplantation, and it is associated with multiple direct and indirect effects. Management of CMV infection and disease has evolved over the years, and clinical guidelines have been recently updated. Universal antiviral prophylaxis and a pre-emptive treatment strategy are options for prevention. A currently-recruiting randomized clinical trial is comparing the efficacy and safety of the two prevention strategies in the highest risk D+R- liver recipients. Drug-resistant CMV infection remains uncommon but is now increasing in incidence. This highlights the currently limited therapeutic options, and the need for novel drug discoveries. Immunotherapy and antiviral drugs with novel mechanisms of action are being investigated, including letermovir (AIC246) and brincidofovir (CMX001). This article reviews the current state of CMV management after liver transplantation, including the updated practice guidelines, and summarizes the data on investigational drugs and vaccines in clinical development.

Prospective, comprehensive, and effective viral monitoring in Cuban children undergoing solid organ transplantation

PURPOSE

In Cuba, viral monitoring in the post-transplant period was not routinely performed. The aim of this research is to identify the most frequent viruses that affect transplanted Cuban children, by implementing a viral follow-up during the post-transplant period.

METHODS

The study population included all Cuban pediatric patients who underwent solid organ transplantation (SOT) between November 2009 and December 2012. A total of 34 transplanted pediatric patients of kidney (n = 11) and liver (n = 23) were prospectively monitored during a 34-week period for viral DNAemia and DNAuria by simultaneous detection of cytomegalovirus (CMV), Epstein-Barr virus, herpes simplex virus type 1 and 2, varicella zoster virus, human herpesvirus 6, human adenovirus, and polyomaviruses (BKV and JCV) using quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

Viral genome of at least one virus was detected in 21 of 34 recipients, 18 patients excreted virus in urine while 12 presented DNAemia. CMV (41.2%) and BKV (35.3%) were the most frequent viruses detected during the follow-up. CMV was the virus mainly associated with clinical symptoms and DNAemia. Its excretion in urine (with cut off value of 219 copies/mL) was associated with detection in plasma (p < 0.001); furthermore, CMV viruria was predictive of CMV viremia (OR:8.4, CI:2.4-29.1, p = 0.001). There was no association between high viral load and clinical complications, due to the prompt initiation of preemptive ganciclovir.

CONCLUSION

This comprehensive viral monitoring program effectively prevents the development of critical viral disease, thus urge the implementation of qRT-PCR as routine for viral monitoring of transplanted Cuban organ recipients.

Cytomegalovirus viral load kinetics in patients with HIV/AIDS admitted to a medical intensive care unit: a case for pre-emptive therapy

Background

Cytomegalovirus (CMV) infection is associated with severe diseases in immunosuppressed patients; however, there is a lack of data for pre-emptive therapy in patients with HIV/AIDS.

Method

This was a retrospective study, which enrolled patients diagnosed with HIV/AIDS (CD4<200 cells/μl), who had detectable CMV viral load (VL) during their stay in an adult medical intensive care unit between 2009–2012.

Results

After screening 82 patients’ records, 41 patients met the enrolment criteria. Their median age was 37 (interquartile range [IQR]: 31–46), and median CD4 count was 29 cells/μl (IQR: 5–55). Sixteen patients (39%) had serial measurements of CMV VL before treatment with ganciclovir. Patients whose baseline CMV VL values were between 1,000–3,000 copies/ml had significantly higher values (median of 14,650 copies/ml) on follow-up testing done 4–12 days later. Those with undetectable VLs at baseline testing had detectable VLs (median of 1,590 copies/ml) mostly within 20 days of follow-up testing. Patients who had VLs >1,000 copies/ml at baseline testing had significantly higher mortality compared to those who had <1,000 copies/ml {hazard ratio of 3.46, p = 0.003 [95% confidence interval (CI): 1.55–7.71]}. Analysis of the highest CMV VL per patient showed that patients who had VLs of >5,100 copies/ml and did not receive ganciclovir had 100% mortality compared to 58% mortality in those who received ganciclovir at VLs of >5,100 copies/ml, 50% mortality in those who were not treated and had low VLs of <5,100 copies/ml, and 44% mortality in those who had ganciclovir treatment at VLs of <5,100 copies/ml (p = 0.084, 0.046, 0.037, respectively).

Conclusion

This study showed a significantly increased mortality in patients with HIV/AIDS who had high CMV VLs, and suggests that a threshold value of 1,000 copies/ml may be appropriate for pre-emptive treatment in this group.

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.

Quantification of cytomegalovirus viral load

Cytomegalovirus (CMV), a member of the Herpesviridae family, is worldwide distributed. After the primary infection, CMV induces a latent infection with possible reactivation(s). It is responsible for severe to life-threatening diseases in immunocompromised patients and in foetuses and newborns of infected mothers. For monitoring CMV load, classical techniques based on rapid culture or pp65 antigenemia are progressively replaced by quantitative nuclear acid tests (QNAT), easier to implement and standardize. A large variety of QNAT are available from laboratory-developed assays to fully-automated commercial tests. The indications of CMV quantification include CMV infection during pregnancy and in newborns, and viral surveillance of grafted and non-grafted immunocompromised patients, patients with bowel inflammatory diseases and those hospitalised in intensive care unit. A close cooperation between virologists and clinicians is essential for optimizing the benefit of CMV DNA monitoring.

Cytomegalovirus infections in solid organ transplantation: a review

Cytomegalovirus (CMV) continues to have a tremendous impact in solid organ transplantation despite remarkable advances in its diagnosis, prevention and treatment. It can affect allograft function and increase patient morbidity and mortality through a number of direct and indirect effects. Patients may develop asymptomatic viremia, CMV syndrome or tissue-invasive disease. Late-onset CMV disease continues to be a major problem in high-risk patients after completion of antiviral prophylaxis. Emerging data suggests that immunologic monitoring may be useful in predicting the risk of late onset CMV disease. There is now increasing interest in the development of an effective vaccine for prevention. Novel antiviral drugs with unique mechanisms of action and lesser toxicity are being developed. Viral load quantification is now undergoing standardization, and this will permit the generation of clinically relevant viral thresholds for the management of patients. This article provides a brief overview of the contemporary epidemiology, clinical presentation, diagnosis, prevention and treatment of CMV infection in solid organ transplant recipients.