GESITRA-SEIMC/REIPI recommendations for the management of cytomegalovirus infection in solid-organ transplant patients

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.

Prevention strategies for cytomegalovirus disease and long-term outcomes in the high-risk transplant patient (D+/R-): experience from the RESITRA-REIPI cohort

BACKGROUND

Cytomegalovirus (CMV)-negative recipients of a graft from a CMV-positive donor (D+/R-) are at high risk of CMV disease. Current preventive strategies include universal prophylaxis (UP) and preemptive therapy (PT). However, the best strategy to prevent CMV disease and achieve better long-term outcomes remains a matter of debate.

METHODS

We analyzed the incidence of CMV disease and long-term outcomes including graft dysfunction and patient mortality at 5 years after transplantation with both preventive strategies. High-risk (D+/R-) kidney and liver transplant recipients from the RESITRA cohort were included.

RESULTS

Of 2410 kidney or liver transplant patients, 195 (8.3%) were D+/R-. The final cohort included 58 liver and 102 kidney recipients. UP was given in 92 patients and 68 received PT; 10.9% and 36.8% developed CMV disease, respectively (P < 0.01). The independent risk factors for CMV disease were PT strategy (hazard ratio [HR], 3.30; 95% confidence interval [CI], 1.6-6.9), kidney transplantation (HR, 3.8; 95% CI, 1.4-9.9), and cyclosporine immunosuppression (HR, 2.4; 95% CI, 1.2-4.7). PT strategy was also a risk factor for CMV disease in both liver transplantation (HR, 11.0; 95% CI, 1.2-98.7) and kidney transplantation (HR, 2.7; 95% CI, 1.3-6.0), independently. The development of CMV replication during the first 2 years after transplantation was a risk factor for graft dysfunction at 5 years after transplantation (odds ratio, 3.4; 95% CI, 1.3-9.0). Nevertheless, no significant differences were seen in either graft dysfunction or mortality between the 2 strategies.

CONCLUSIONS

The study supports the benefit of the UP strategy to prevent CMV disease in D+/R- liver or kidney transplant patients. The development of CMV replication during the first 2 years after transplantation was associated with graft dysfunction at 5 years after transplantation.

[Infections by Epstein-Barr virus and cytomegalovirus]

Infections by Epstein-Barr virus is the most common cause of infectious mononucleosis. We describe the diagnosis and different serological patterns, as well as its major complications related to the development of malignancies, lymphoproliferative disorders and autoimmune diseases. There is no effective treatment. Cytomegalovirus is the second cause of mononucleosis syndrome and the first of congenital infection in our environment. It has an high morbidity and mortality in immunocompromised patients, mainly solid organ transplants, bone marrow and coinfection by human immunodeficiency virus. Its treatment is based on antivirals, mainly ganciclovir and valganciclovir. We describe its management, adverse effects, new drugs and prophylaxis.

Clinical immune-monitoring strategies for predicting infection risk in solid organ transplantation

Infectious complications remain a leading cause of morbidity and mortality after solid organ transplantation (SOT), and largely depend on the net state of immunosuppression achieved with current regimens. Cytomegalovirus (CMV) is a major opportunistic viral pathogen in this setting. The application of strategies of immunological monitoring in SOT recipients would allow tailoring of immunosuppression and prophylaxis practices according to the individual's actual risk of infection. Immune monitoring may be pathogen-specific or nonspecific. Nonspecific immune monitoring may rely on either the quantification of peripheral blood biomarkers that reflect the status of a given arm of the immune response (serum immunoglobulins and complement factors, lymphocyte sub-populations, soluble form of CD30), or on the functional assessment of T-cell responsiveness (release of intracellular adenosine triphosphate following a mitogenic stimulus). In addition, various methods are currently available for monitoring pathogen-specific responses, such as CMV-specific T-cell-mediated immune response, based on interferon-γ release assays, intracellular cytokine staining or main histocompatibility complex-tetramer technology. This review summarizes the clinical evidence to date supporting the use of these approaches to the post-transplant immune status, as well as their potential limitations. Intervention studies based on validated strategies for immune monitoring still need to be performed.

Risk factors and outcomes of bacteremia caused by drug-resistant ESKAPE pathogens in solid-organ transplant recipients

BACKGROUND

Although infections due to the six ESKAPE pathogens have recently been identified as a serious emerging problem, information regarding bacteremia caused by these organisms in solid-organ transplant (SOT) recipients is lacking. We sought to determine the frequency, risk factors, and outcomes of bacteremia due to drug-resistant ESKAPE (rESKAPE) organisms in liver, kidney, and heart adult transplant recipients.

METHODS

All episodes of bacteremia prospectively documented in hospitalized SOT recipients from 2007 to 2012 were analyzed.

RESULTS

Of 276 episodes of bacteremia, 54 (19.6%) were due to rESKAPE strains (vancomycin-resistant Enterococcus faecium [0], methicillin-resistant Staphylococcus aureus [5], extended-spectrum β-lactamase-producing Klebsiella pneumoniae [10], carbapenem-resistant Acinetobacter baumannii [8], carbapenem- and quinolone-resistant Pseudomonas aeruginosa [26], and derepressed chromosomal β-lactam and extended-spectrum β-lactamase-producing Enterobacter species [5]). Factors independently associated with rESKAPE bacteremia were prior transplantation, septic shock, and prior antibiotic therapy. Patients with rESKAPE bacteremia more often received inappropriate empirical antibiotic therapy than the others (41% vs. 21.6%; P=0.01). Overall case-fatality rate (30 days) was higher in patients with rESKAPE bacteremia (35.2% vs. 14.4%; P=0.001).

CONCLUSIONS

Bacteremia due to rESKAPE pathogens is frequent in SOT recipients and causes significant morbidity and mortality. rESKAPE organisms should be considered when selecting empirical antibiotic therapy for hospitalized SOT recipients presenting with septic shock, particularly those with prior transplantation and antibiotic use.

Does the calcineurin inhibitor have influence on cytomegalovirus infection in heart transplantation?

Cytomegalovirus (CMV) infection is a major cause of morbidity and mortality in heart transplant (HTx). Our aim was to analyze the rate of CMV infection in HTx patients receiving treatment with cyclosporine (CsA) or tacrolimus (Tac). Ninety-five patients were randomized to receive either CsA (53.7%) or Tac (46.3%). We performed prophylaxis with valganciclovir in patients with the highest risk of CMV infection. We considered CMV infection as an increased viral load or the presence of CMV in histological samples. We analyzed baseline characteristics, CMV infection, and other complications. Event-free rates were calculated using the Kaplan-Meier method. There were no significant differences in baseline characteristics between both groups. CMV infection was detected in 31.6% of patients (in 66.7% due to asymptomatic replication). The group treated with Tac had a lower rate of CMV infection (15.9% vs. 45.1%, p = 0.002) and longer CMV infection-free survival time (1440 vs. 899 d, p = 0.001). No differences were observed in the complications analyzed in both groups. The independent risk factors for infection identified in the multivariate analysis were treatment with CsA and bacterial infections. This was the first study to demonstrate a lower rate of CMV infection in patients treated with Tac vs. those treated with CsA after HTx.

Use of high-dose ganciclovir for the treatment of cytomegalovirus replication in solid organ transplant patients with ganciclovir resistance-inducing mutations

BACKGROUND

Experience with high-dose ganciclovir for the management of resistant cytomegalovirus (CMV) replication in transplant patients is limited despite its adoption as an effective therapy by some consensus documents.

METHODS

We studied six cases of CMV replication in solid organ transplant patients whose genotypic testing showed mutations associated with different levels of resistance to ganciclovir. All were treated with high-dose intravenous ganciclovir (7.5-10 mg/kg/12 hr) or oral valganciclovir (1350-1800 mg/12 hr) corrected according to creatinine clearance. The virologic response was considered positive if the CMV plasma viral load was undetectable. Safety was evaluated by clinical assessment, including the review of vital signs and laboratory tests.

RESULTS

All patients had asymptomatic replication, except one who had digestive disease. Four patients received universal prophylaxis with valganciclovir. Two patients received preemptive therapy with valganciclovir for individual episodes of replication. Two of the six patients received steroid boluses before the episode of replication by resistant CMV. All patients responded to treatment, including those with mutations associated with a high level of ganciclovir resistance. Four patients had neutropenia (<1.5 × 10/L), but only one received treatment.

CONCLUSIONS

High-dose ganciclovir/valganciclovir can be an option in the treatment of resistant CMV replication and could be considered an alternative treatment in nonsevere patients for whom the use of foscarnet should be avoided. The toxicity of this regimen does not appear to limit its use.

Epidemiology, risk factors and impact on long-term pancreatic function of infection following pancreas-kidney transplantation

Limited information exists about epidemiology and risk factors of infection following pancreas-kidney transplantation and its impact on long-term pancreatic graft function. A retrospective chart review of episodes of severe infection in consecutive pancreas-kidney transplantations in a single institution was performed to assess the epidemiology, risk factors for infection and their impact on the development of pancreatic graft dysfunction. Ninety-four (81%) of 116 recipients (median follow-up of 1492 days; mean 1594) developed 248 episodes of severe infection. Bacterial infections were present in 208 episodes, with 12% of the isolates resistant to antibiotics used in prophylaxis. There were 40 episodes of fungal infection in 32 patients (28%) (mostly Candida spp), and CMV disease appeared in 20 patients (17%), of which 50% appeared after the third month following surgery. The multivariate analysis identified that surgical re-intervention and the use of steroid pulses were independently associated with the development of any infection. Additionally, pre-transplant evidence of peripheral artery disease, a longer cold ischaemia time and high transfusional requirements were associated with fungal infections. Cytomegalovirus (CMV) mismatch was independently related to CMV disease and female sex, and bladder drainage of the exocrine pancreas was associated with urinary tract infection. At the end of follow-up, 29 patients (25%) had developed severe pancreatic graft dysfunction, and fungal infection was independently associated with it. Our study identifies a subset of pancreas-kidney transplant recipients at a higher risk of developing severe infection. Fungal infection is an independent risk factor for the development of severe pancreatic graft dysfunction.

Pretransplant interferon-γ secretion by CMV-specific CD8+ T cells informs the risk of CMV replication after transplantation

In this prospective study we analyzed pretransplant interferon-γ secretion by cytomegalovirus (CMV)-specific CD8+ T cells to assess its possible utility in determining the risk of CMV replication after solid organ transplantation. A total of 113 lung and kidney transplant patients were enrolled in the study but only 55 were evaluable. All CMV-seronegative recipients were pretransplant "nonreactive" (IFNγ <0.2 IU/mL) (11/11), whereas 30/44 (68.2%) CMV-seropositive (R+) recipients were "reactive" (IFNγ ≥0.2 IU/mL) and 14/44 (31.8%) were "nonreactive". In the R(+) "nonreactive" group, 7/14 (50%) developed posttransplant CMV replication, whereas the virus replicated only in 4/30 (13.3%) of the R(+) "reactive" patients (p = 0.021). According to the best multivariate model, pretransplant "nonreactive" recipients receiving an organ from a CMV-seropositive donor had a 10-fold increased risk of CMV replication compared to pretransplant "reactive" recipients (adjusted OR 10.49, 95% CI 1.88-58.46). This model displayed good discrimination ability (AUC 0.80) and calibration (Hosmer-Lemeshow test, p = 0.92). Negative and positive predictive values were 83.7% and 75%, respectively. The accuracy of the model was 82%. Therefore, assessment of interferon-γ secretion by cytomegalovirus (CMV)-specific CD8+ T cells prior to transplantation is useful in informing the risk of posttransplant CMV replication in solid organ transplant patients.

CMV: Prevention, Diagnosis and Therapy

Cytomegalovirus (CMV) is the most common infection after organ transplantation and has a major impact on morbidity, mortality and graft survival. Optimal prevention, diagnosis and treatment of active CMV infection enhance transplant outcomes, and are the focus of this section. Methods to prevent CMV include universal prophylaxis and preemptive therapy; each has its merits, and will be compared and contrasted. Diagnostics have improved substantially in recent years, both in type and quality, allowing for more accurate and savvy treatment; advances in diagnostics include the development of an international standard, which should allow comparison of results across different methodologies, and assays for cellular immune function against CMV. Therapy primarily involves ganciclovir, now rendered more versatile by data suggesting oral therapy with valganciclovir is not inferior to intravenous therapy with ganciclovir. Treatment of resistant virus remains problematic, but is enhanced by the availability of multiple novel therapeutic agents.

Recommendations on the use of everolimus in lung transplantation

The antiproliferative effect of everolimus provides a therapeutic option in the immunosuppression therapy of lung transplantation, by reducing both the risk of acute rejection and the process of progressive fibrosis that determines chronic graft rejection. However, few data on the use of everolimus in lung transplantation have been published to date, and the specific indications of the drug, along with the most adequate time for its introduction or dosing, have not been defined yet. The aim of this article is to propose recommendations for the use of everolimus in lung transplant recipients, including indications, dosing schedules and the use of concomitant immunosuppression. This consensus document has been developed by experts of all the Spanish lung transplant groups from the review of the existing literature and the clinical experience.

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

BACKGROUND

Valganciclovir preemptive therapy guided by the viral load is the current strategy recommended for preventing CMV disease in CMV-seropositive Solid Organ Transplant Recipients (SOTR) at lower risk for developing CMV infection. However, universal viral load cut-off has not been established for initiating therapy.

OBJECTIVES

Our goal was to define and validate a standardized cut-off determined in plasma by real-time PCR assay for initiating preemptive therapy in this population.

STUDY DESIGN

A prospective cohort study of consecutive cases of CMV-seropositive SOTR was carried out. The cut-off value was determined in a derivation cohort and was validated in the validation cohort. Viral loads were determined using the Quant CMV LightCycler 2.0 real-time PCR System (Roche Applied Science) and results were standardized using the WHO International Standard for human CMV.

RESULTS

A viral load of 3983 IU/ml (2600 copies/ml) was established as the optimal cut-off for initiating preemptive therapy in a cohort of 141 patients with 982 tests and validated in a cohort of 252 recipients with a total of 2022 test. This cut-off had a 99.6% NPV indicating that the great majority of patients at lower risk will not develop CMV disease without specific antiviral therapy. The high sensitivity and specificity (89.9% and 88.9%, respectively) and the relatively small numbers of patients with CMV disease confirm that real-time PCR was optimal.

CONCLUSIONS

We have established a cut-off viral load for starting preemptive therapy for CMV-seropositive SOT recipients. Our results emphasized the importance of a mandatory follow-up protocol for CMV-seropositive patients receiving preemptive treatment.

Evaluating the risk of transmission of infection from donor to recipient of a solid organ transplantation

In the context of solid organ transplantation, screening of potential organ donors is crucial, and should be performed with great rigor to minimize the risk of transmission of certain infectious processes. This review aims to update understanding of the possible pathologies involved, as well as of emerging infections that, as a result of globalization, are gaining increasing prominence on a daily basis.

Cytomegalovirus infection in solid organ transplantation

Cytomegalovirus infection remains a serious threat to solid transplant recipients. Despite advances in this field, there are still difficulties in the diagnosis of the disease and there are questions about the best and most cost-effective strategy to prevent infection and its direct and indirect consequences in the short and long term. All these points are discussed and updated in this chapter.

Prophylaxis versus preemptive therapy for cytomegalovirus disease in high-risk liver transplant recipients

Cytomegalovirus (CMV) infection is an opportunistic infection frequently found after solid organ transplantation, and it contributes significantly to mortality and morbidity. CMV-seronegative recipients of grafts from CMV-seropositive donors have the highest risk of CMV disease. The most appropriate strategy for preventing CMV disease in this population is a matter of active debate. In this study, we compared prophylaxis and preemptive therapy for the prevention of CMV disease in donor-seropositive/recipient-seronegative (D+ /R-) liver recipients. To this end, we selected a retrospective cohort of liver recipients (1992-2009) for analysis. D+ /R- patients were identified from the liver transplant program database. Eighty of 878 consecutive liver recipients (9%) were D+ /R-. Six of these patients died within 30 days of transplantation and were excluded. Thirty-five of the remaining D+ /R- patients (47%) received prophylaxis, and 39 patients (53%) followed a preemptive strategy based on CMV antigenemia surveillance. Fifty-four (73%) were men, the median age was 49 years (range = 15-68 years), and the mean follow-up was 68 months (range = 8-214 months). The baseline characteristics and the initial immunosuppressive regimens were similar for the 2 groups. Ganciclovir or valganciclovir was the antiviral drug used initially in both strategy groups. CMV disease occurred more frequently among D+ /R- liver recipients receiving preemptive therapy (33.3% versus 8.6% for the prophylaxis group, P = 0.01), whereas late-onset CMV disease was found only in patients receiving prophylaxis (5.7% versus 0% for the preemptive therapy group, P = 0.22). No significant differences in acute allograft rejection, other opportunistic infections, or case fatality rates were observed. According to our data, prophylaxis was more effective than preemptive therapy in preventing CMV disease in high-risk liver transplant recipients.

[Prevention of cytomegalovirus disease in lung transplantation]

Lung transplant recipients, more than other organ transplant recipients, are at particular risk for cytomegalovirus (CMV) infection and disease. CMV prevention avoids the indirect effects of this virus, such as opportunistic fungal infections and obliterative bronchiolitis, the latter being the major limiting factor in the long-term success of lung-transplantation. CMV prevention strategies have significantly reduced CMV disease and CMV-related mortality. Two major strategies are commonly used for CMV prevention: universal prophylaxis and preemptive therapy. In lung transplant recipients, the efficacy and safety of preemptive treatment have not been studied and therefore, cannot be recommended. Universal prophylaxis is the best strategy for preventing CMV disease in lung transplant recipients. There is no consensus on the optimal duration of prophylaxis, but the recently published GESITRA-SEIMC/REIPI 2011 Guidelines for the management of CMV infection in solid-organ transplant patients recommend 6 months posttransplantation. In D+/R- recipients, this period can be prolonged to 12 months if there are difficulties in monitoring at 6 months posttransplantation. The future of prevention will probably depend on immunoguided strategies.

[Prophylaxis of cytomegalovirus infection in pancreatic transplantation]

Pancreatic transplantation carries a higher risk of cytomegalovirus (CMV) infection than renal transplantation alone. The management of CMV disease in pancreatic transplantation depends on the risk indicated by the donor's and recipient's serological profiles (CMV IgG) and the use of antibodies as immunosuppressive therapy (especially thymoglobulin). Most clinical guidelines recommend the use of prophylaxis in preference to preemptive therapy in both donor (D)+/recipient (R)- and D+/R+ pancreatic transplantations. In combinations with highest risk (D+/R-), prophylaxis with valganciclovir 900mg per day for 3 to 6 months is recommended, adjusted to renal funtion. In D+/R+ combinations, if antibody therapy was used in the transplant or in rejection, valgancioclovir prophylaxis is also recommended for 1 to 3 months. When prophylaxis is finished, in both cases, viral load determination (quantitative polymerase chain reaction of CMV) or antigenemia should be carried out for the first year. In D-/R-combinations, preemptive therapy can be considered with determinations of viral load or antigenemia at each follow-up visit during the first year. Once prophylaxis has been suspended, special attention should be paid to the development of delayed CMV disease.

[Prophylaxis of cytomegalovirus infection in heart transplantation]

Cytomegalovirus (CMV) is a common complication after heart transplantation, affecting almost half of all recipients. The clinical spectrum of this infection includes, in order of greater to lesser severity, latent infection, asymptomatic viremia, CMV syndrome and CMV disease. CMV is associated with rejection and vascular graft disease and is a major cause of morbidity and mortality. The factors most frequently involved in susceptibility to this infection and its severity are donor and recipient CMV serological status, the intensity of immunosuppression and the type of immunosuppressive agents used. The management strategies of this infection include universal or targeted prophylaxis, preemptive therapy and treatment of established disease. The use of preventive measures significantly reduces the incidence of symtomatic infection or CMV disease, which has been reported to be less than 3% in some recent series.

Successful outcome of ganciclovir-resistant cytomegalovirus infection in organ transplant recipients after conversion to mTOR inhibitors

Ganciclovir-resistant (GanR) cytomegalovirus (CMV) infection after organ transplantation is emerging as a significant therapeutic challenge. We report two cases of GanR CMV infection successfully managed by switching immunosuppression from calcineurin inhibitors to an mTOR inhibitor-based regimen. This salvage therapy should be considered when other options are not available.

Spanish society of liver transplantation (SETH) consensus recommendations on hepatitis C virus and liver transplantation

In November 2010, the Spanish Society of Liver Transplantation (Sociedad Española de Trasplante Hepático, SETH) held a consensus conference. One of the topics of debate was liver transplantation in patients with hepatitis C. This document reviews (i) the natural history of post-transplant hepatitis C, (ii) factors associated with post-transplant prognosis in patients with hepatitis C, (iii) the role of immunosuppression in the evolution of recurrent hepatitis C and response to antiviral therapy, (iv) antiviral therapy, both before and after transplantation, (v) follow-up of patients with recurrent hepatitis C and (vi) the role of retransplantation.