Varicella zoster virus (VZV) and herpes simplex virus (HSV) in solid organ transplant patients

Causality between herpes virus infections and allograft dysfunction after tissue and organ transplantation: a two-sample bidirectional Mendelian randomization study

Background

Observational studies have suggested that herpes virus infections increase the risk of allograft dysfunction after tissue and organ transplantation, but it is still unclear whether this association is causal. The aim of this study was to assess the causal relationship between four herpes virus infections and allograft dysfunction.

Methods

We used two-sample bidirectional Mendelian randomization (MR) to investigate the causality between four herpes virus infections - cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV) and varicella zoster virus (VZV) - and allograft dysfunction after tissue and organ transplantation. Based on summary data extracted from genome-wide association studies (GWAS), we chose eligible single nucleotide polymorphisms (SNPs) as instrumental variables. The Inverse variance weighted (IVW) method was used as the main analysis method, supplemented by Weighted median and MR-Egger analyses. The MR-PRESSO test, MR-Egger intercept test, heterogeneity test, leave-one-out analysis and funnel plot were used to analyze the sensitivity of MR results.

Results

We found EBV early antigen-D (EA-D) antibody levels and shingles were the only two variables associated with an increased risk of allograft dysfunction. No evidence of allograft dysfunction increasing the risk of the four herpes virus infections was observed. Sensitivity analyses confirmed the robustness of our results.

Conclusions

Our results suggest that EBV and VZV are involved in graft rejection or dysfunction. However, the relationship between CMV and HSV infections and allograft dysfunction remains unclear and requires further clarification.

Epidemiology and Management of Infections in Liver Transplant Recipients

Background: Improvements in liver transplant (LT) outcomes are attributed to advances in surgical techniques, use of potent immunosuppressants, and rigorous pre-LT testing. Despite these improvements, post-LT infections remain the most common complication in this population. Bacteria constitute the most common infectious agents, while fungal and viral infections are also frequently encountered. Multi-drug-resistant bacterial infections develop because of polymicrobial overuse and prolonged hospital stays. Immediate post-LT infections are commonly caused by viruses. Conclusions: Appropriate vaccination, screening of both donor and recipients before LT and antiviral prophylaxis in high-risk individuals are recommended. Antimicrobial drug resistance is common in high-risk LT and associated with poor outcomes; epidemiology and management of these cases is discussed. Additionally, we also discuss the effect of coronavirus disease 2019 (COVID-19) infection and monkeypox in the LT population.

Opportunistic Infections Post-Lung Transplantation: Viral, Fungal, and Mycobacterial

Opportunistic infections are a leading cause of lung transplant recipient morbidity and mortality. Risk factors for infection include continuous exposure of the lung allograft to the external environment, high levels of immunosuppression, impaired mucociliary clearance and decreased cough reflex, and impact of the native lung microbiome in single lung transplant recipients. Infection risk is mitigated through careful pretransplant screening of recipients and donors, implementation of antimicrobial prophylaxis strategies, and routine surveillance posttransplant. This review describes common viral, fungal, and mycobacterial infectious after lung transplant and provides recommendations on prevention and treatment.

Herpes Virus Infections in Kidney Transplant Patients (HINT) - a prospective observational cohort study

BACKGROUND

Kidney transplant recipients receive maintenance immunosuppressive therapy to avoid allograft rejection resulting in increased risk of infections and infection-related morbidity and mortality. Approximately 98% of adults are infected with varicella zoster virus, which upon reactivation causes herpes zoster. The incidence of herpes zoster is higher in kidney transplant recipients than in immunocompetent individuals, and kidney transplant recipients are at increased risk of severe herpes zoster-associated disease. Vaccination with adjuvanted recombinant glycoprotein E subunit herpes zoster vaccine (RZV) prevents herpes zoster in older adults with excellent efficacy (90%), and vaccination of kidney transplant candidates is recommended in Danish and international guidelines. However, the robustness and duration of immune responses after RZV vaccination, as well as the optimal timing of vaccination in relation to transplantation remain unanswered questions. Thus, the aim of this study is to characterize the immune response to RZV vaccination in kidney transplant candidates and recipients at different timepoints before and after transplantation.

METHODS

The Herpes Virus Infections in Kidney Transplant Patients (HINT) study is a prospective observational cohort study. The study will include kidney transplant candidates on the waiting list for transplantation (n = 375) and kidney transplant recipients transplanted since January 1, 2019 (n = 500) from all Danish kidney transplant centers who are offered a RZV vaccine as routine care. Participants are followed with repeated blood sampling until 12 months after inclusion. In the case of transplantation or herpes zoster disease, additional blood samples will be collected until 12 months after transplantation. The immune response will be characterized by immunophenotyping and functional characterization of varicella zoster virus-specific T cells, by detection of anti-glycoprotein E antibodies, and by measuring cytokine profiles.

DISCUSSION

The study will provide new knowledge on the immune response to RZV vaccination in kidney transplant candidates and recipients and the robustness and duration of the response, potentially enhancing preventive strategies against herpes zoster in a population at increased risk.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT05604911).

Opportunistic Infections Post-Lung Transplantation: Viral, Fungal, and Mycobacterial

Opportunistic infections are a leading cause of lung transplant recipient morbidity and mortality. Risk factors for infection include continuous exposure of the lung allograft to the external environment, high levels of immunosuppression, impaired mucociliary clearance and decreased cough reflex, and impact of the native lung microbiome in single lung transplant recipients. Infection risk is mitigated through careful pretransplant screening of recipients and donors, implementation of antimicrobial prophylaxis strategies, and routine surveillance posttransplant. This review describes common viral, fungal, and mycobacterial infectious after lung transplant and provides recommendations on prevention and treatment.

Establishing a research production line in real-life settings: the case of Hepatitis C management in a viral hepatitis specialized Egyptian center

Efforts toward eradicating the Hepatitis C virus (HCV) have advanced rapidly, due to the development of direct-acting antivirals (DAAs), especially with the appearance of pan-genotypic combinations. Real-world studies, in particular, have verified the efficacy and safety of DAA combinations documented in registration trials. This review documents the results of using DAA combinations in real-life settings in everyday clinical practice in Egypt, the country with the highest prevalence of HCV. The significant number of treated patients in Egypt, which exceeded four million allowed tremendous data about the results of HCV management in real-life settings for different treatment regimens and disease conditions. DAA combinations have resulted in high sustained virologic response rates (SVR12) and few adverse reactions in real-life settings. SVR12 rates ranged from 90% to 100%, depending on the combination of drugs used, the HCV genotype, and the stage of liver disease. Most adverse reactions reported in real-world settings were mild and resulted in treatment discontinuation in only a minority of cases. Data from real-life studies covered most aspects of HCV management that were lacking after initial approval studies. More research is needed to tailor treatment and produce generic HCV combinations to overcome the residual limitations of the currently available DAAs.

Viral infections in lung transplantation

Viral infections account for up to 30% of all infectious complications in lung transplant recipients, remaining a significant cause of morbidity and even mortality. Impact of viral infections is not only due to the direct effects of viral replication, but also to immunologically-mediated lung injury that may lead to acute rejection and chronic lung allograft dysfunction. This has particularly been seen in infections caused by herpesviruses and respiratory viruses. The implementation of universal preventive measures against cytomegalovirus (CMV) and influenza (by means of antiviral prophylaxis and vaccination, respectively) and administration of early antiviral treatment have reduced the burden of these diseases and potentially their role in affecting allograft outcomes. New antivirals against CMV for prophylaxis and for treatment of antiviral-resistant CMV infection are currently being evaluated in transplant recipients, and may continue to improve the management of CMV in lung transplant recipients. However, new therapeutic and preventive strategies are highly needed for other viruses such as respiratory syncytial virus (RSV) or parainfluenza virus (PIV), including new antivirals and vaccines. This is particularly important in the advent of the COVID-19 pandemic, for which several unanswered questions remain, in particular on the best antiviral and immunomodulatory regimen for decreasing mortality specifically in lung transplant recipients. In conclusion, the appropriate management of viral complications after transplantation remain an essential step to continue improving survival and quality of life of lung transplant recipients.

Varicella caused by airborne transmission of a localised herpes zoster infection in a family

Localised herpes zoster infections spread by direct contact with active skin lesion, but airborne transmission is rare. We report a case of varicella from airborne transmission of a localised herpes zoster infection in a family. The patient was a 15-year-old boy who had never been vaccinated against the varicella-zoster virus (VZV). He likely developed varicella from his father, whom the patient lived with. The patient’s father developed a localised herpes zoster infection 2 weeks prior. The patient’s varicella was hypothesised to be due to VZV spread via airborne transmission from the father’s localised infection. To decrease the number of varicella cases, routine vaccination of children against VZV is essential, and immunisation against VZV in middle-aged and elderly patients is also necessary.

Opportunistic Infections in Transplant Patients

Transplants have become common with excellent patient and graft outcomes owing to advances in surgical technique, immunosuppression, and antimicrobial prophylaxis. In 2017, 34,770 solid organ transplants were performed in the United States. For solid organ transplant recipients, infection remains a common complication owing to the regimens required to prevent rejection. Opportunistic infections, which are infections that are generally of lower virulence within a healthy host but cause more severe and frequent disease in immunosuppressed individuals, typically occur in the period 1 month to 1 year after transplantation. This article focuses on opportunistic infections in the solid organ transplant recipient.

Fatal disseminated visceral varicella zoster virus infection in a renal transplant recipient

We report a case of fatal disseminated varicella zoster virus (VZV) with delayed-onset rash in a 66-year-old female more than 2 years following uncomplicated deceased donor renal transplantation. Whilst on a stable regimen of maintenance immunosuppression, the patient presented with chest and abdominal pain with concomitant hepatitis and pancreatitis. After pursuing multiple other potential causes of her symptoms, the correct diagnosis of VZV was only suspected after the development of a widespread vesicular rash-11 days after her initial symptoms. Despite antiviral therapy and inotropic support in the intensive care unit, the patient died. Simultaneous VZV hepatitis and pancreatitis in solid organ transplant recipients is uncommon. The new inactivated VZV vaccines have the potential to prevent post-transplant infections, with promising early clinical data on safety and efficacy in renal transplant recipients. VZV is an important preventable infection that should be considered in immunocompromised patients, even in the absence of rash.

Pleural effusions induced by human herpesviruses in the immunocompetent host

METHODS

A computer-based search of the English literature for articles relative to Human Herpesviruses (HHVs) infection and pleural effusions (PEs) in the immunocompetent host was performed in PubMed and Scopus. The reference lists of the retrieved articles were also reviewed for relevant articles.

RESULTS

A total of 20 articles satisfied the selection criteria and were included in the study. In the majority of the articles, PEs were reported as clinical complications of systemic HHV-induced infection. The frequency of HHVs within the reported cases was five for HHV-1/2, one for HHV-3, six for HHV-4, six for HHV-5 and one for HHV-6. One case involved HHV-4 and HHV-5 co-infection. No case of HHV-7 or HHV-8 related PE in the immunocompetent host was retrieved.

CONCLUSIONS

Pleural effusions in the immunocompetent host occur in severe viral infections and can be due to comorbidities (or septic complications) or due to the direct HHV pathogenicity although research relative to the susceptibility of pleural mesothelial cells to HHV infection is lacking. HHV pathogenicity needs to be studied further as it could explain undiagnosed PEs.

Non-infectious diffuse vesiculobullous rash in a pancreas and renal transplant recipient

Solid organ transplant patients are well established to be at risk of herpes simplex virus and varicella zoster virus infection and reactivation. We present a case of a 41-year-old woman with a history of pancreas and renal transplant who presented with what appeared to be disseminated herpes simplex virus or varicella zoster virus induced rash, but who was ultimately diagnosed and treated as linear IgA bullous dermatosis. This case alerts physicians to other non-infectious dermatoses as a cause of vesiculobullous rash in solid organ transplant patients.

Titration of cell-associated varicella-zoster virus with the MV9G reporter cell line for antiviral studies

Titration of the cell-associated virus (CAV) of varicella-zoster virus (VZV) is essential for antiviral studies. A VZV reporter cell line, MV9G, generated in our previous study expresses firefly luciferase upon CAV infection in a dose-dependent manner, suggesting that use of the cell line for titration is feasible. In this study, MeWo cells infected with VZV vaccine Oka (vOka) strain or with clinical isolates obtained from patients with varicella or zoster were used as CAV. A co-culture of MV9G cells with the virus-infected MeWo cells were set up and optimized for titration of CAV. Luciferase activities of MV9G cells measured as relative light units (RLUs) of chemiluminescence correlated well (r > 0.9, p < 0.05) both with quantities of viral DNAs measured by TaqMan PCR and with numbers of viral foci detected by immunostaining with a monoclonal antibody against VZV IE62. In addition, the usefulness of MV9G for antiviral studies was exemplified by treatment of the VZV-infected cells with various concentrations of acyclovir. Thus, the reporter cell-based titration of CAV by measuring the induced RLUs may be a reliable way to estimate viral foci and viral DNAs.

Vaccination practices in End Stage Renal Failure and Renal Transplantation; Review of current guidelines and recommendations

Due to the increased burden of infectious complications following solid organ transplantation, vaccination against common pathogens is a hugely important area of discussion and application in clinical practice. Reduction in infectious complications will help to reduce morbidity and mortality post-transplantation. Immunisation history is invaluable in the work-up of potential recipients. Knowledge of the available vaccines and their use in transplant recipients, donors and healthcare providers is vital in the delivery of quality care to transplant recipients. This article will serve as an aide-memoire to transplant physicians and health care professionals involved in managing transplant recipients as it provides an overview of different types of vaccines, timing of vaccination, vaccines contraindicated post solid organ transplantation and travel vaccines.

Dermatological Complications After Solid Organ Transplantation

Organ transplant recipients (OTRs) are a population at high risk for cutaneous adverse events. Their early recognition and appropriate treatment is an important component of the clinical management of OTRs and should be optimally dealt with by dermatologists working in the context of a transplant dermatology clinic. Skin examination should be a standard procedure before performing organ transplantation to assess conditions which may be difficult to manage after the transplant procedure has been performed or which may represent a contraindication to transplantation, e.g., malignant melanoma. It also offers an opportunity to educate patients on skin care after organ transplantation. Skin infections can occur at any time after organ transplantation and include viral, bacterial, and fungal opportunistic infections. The risk of reactivation of latent viruses, such as varicella-zoster virus (VZV) and cytomegalovirus (CMV), is high. Bacterial infections are frequent and may be caused by unusual agents such Actinomyces, Mycobacteria, Legionella, or Nocardia. A large spectrum of fungal infections may occur, ranging from superficial (e.g., dermatophytes) to deeper and more severe ones (Alternaria, Aspergillus, Cryptococcus, Histoplasma). Drug-related idiosyncratic reactions usually occur early after the introduction of the causative drug, e.g., hypersensitivity reaction to azathioprine. On the long-term run, cutaneous effects due to cumulative drug toxicity, e.g., sebaceous hyperplasia from cyclosporine, may appear. Rare immunologically driven inflammatory reactions may occur in OTRs such as GVH or autoimmune disease. Tumors are particularly frequent. Kaposi's sarcoma, associated with persistent human herpes virus 8 (HHV8) infection, and cutaneous anaplastic large-cell lymphoma (ALCL) occur early after transplantation. Other cancers, such as nonmelanoma skin cancer (NMSCs), associated with persistent human papillomavirus (HPV) infections, malignant melanoma, Merkel cell carcinoma, or adnexal tumors, manifest later with an incidence which is much higher than observed in the general population. The incidence increases further after a first NMSC occurs.

α Herpes Virus Infections Among Renal Transplant Recipients

The α herpes viruses HSV-1, HSV-2, and VZV often reactivate in the setting of immune suppression after solid organ transplantation. Oral or genital mucocutaneous disease is the most common clinical manifestation of HSV disease while VZV manifests as varicella (or chickenpox) or reactivation herpes zoster, characterized by a diffuse rash, or a painful unilateral vesicular eruption in a dermatomal distribution, respectively. The diagnosis of HSV and VZV is primarily based on history and clinical presentation, although diagnostic tests may be necessary for atypical presentations of disease. Treatment usually involves oral or intravenous antiviral therapy, depending on severity of illness.

Review of Infectious Disease Prophylaxis in Solid Organ Transplantation

As immunosuppressive therapy has evolved over the years, rejection rates in solid organ transplant have declined, but infections remain a significant cause of morbidity and mortality in this population. Prophylaxis against bacterial, viral, and fungal infections is often used to prevent infection from common pathogens during high-risk periods. As an integral part of the multidisciplinary medical team, it is important that nurses caring for transplant recipients be familiar with methods to detect and prevent infectious diseases in this population. This article presents a review of risk factors for and prevalence of common infectious pathogens, as well as important considerations regarding prophylactic medications in solid organ transplant recipients.

Herpes zoster in kidney transplant recipients: protective effect of anti-cytomegalovirus prophylaxis and natural killer cell count. A single-center cohort study

Despite its impact on quality of life and potential for complications, specific risk and protective factors for herpes zoster (HZ) after kidney transplantation (KT) remain to be clarified. We included 444 patients undergoing KT between November 2008 and March 2013. Peripheral blood lymphocyte subpopulations were measured at baseline and months 1 and 6. The risk factors for early (first post-transplant year) and late HZ (years 1-5) were separately assessed. We observed 35 episodes of post-transplant HZ after a median follow-up of 48.3 months (incidence rate: 0.057 per 1000 transplant-days). Median interval from transplantation was 18.3 months. Six patients (17.1%) developed disseminated infection. Postherpetic neuralgia occurred in 10 cases (28.6%). The receipt of anti-cytomegalovirus (CMV) prophylaxis with (val)ganciclovir decreased the risk of early HZ [adjusted hazard ratio (aHR): 0.08; 95% CI: 0.01-1.13; P-value = 0.062], whereas the natural killer (NK) cell at month 6 was protective for the occurrence of late HZ [aHR (per 10-cells/μl increase): 0.94; 95% CI: 0.88-1.00; P-value = 0.054]. In conclusion, two easily ascertainable factors (whether the patient is receiving anti-CMV prophylaxis and the NK cell count at month 6) might be potentially useful to tailor preventive strategies according to individual susceptibility to post-transplant HZ.

Herpes simplex virus-2 transmission following solid organ transplantation: Donor-derived infection and transplantation from prior organ recipients

BACKGROUND

Owing to limited availability of donor organs, previous solid organ transplant (SOT) recipients are increasingly considered as potential organ donors. We report donor-derived transmission of herpes simplex virus type-2 (HSV-2) to two clusters of SOT recipients with transmission from the original donor and an HSV-2-infected recipient who subsequently became a donor.

METHODS

We reviewed medical records of the donors and recipients in both clusters. Pre-transplant serology and virological features of HSV-2 were characterized. Genotyping of HSV-2 isolates to determine potential for donor transmission of HSV-2 through transplantation of organs from prior organ recipients was performed.

RESULTS

A kidney-pancreas recipient died day 9 post transplant. Following confirmation of brain death, the lungs and recently transplanted kidney were donated to two further recipients. The liver was not retrieved, but biopsy confirmed HSV-2 infection. Testing on the original donor showed negative HSV-2 polymerase chain reaction and HSV immunoglobulin (Ig)M, but positive HSV-2 IgG. The liver recipient from the original donor developed HSV-2 hepatitis and cutaneous infection that responded to treatment with intravenous acyclovir. In the second cluster, lung and kidney recipients both developed HSV-2 viremia that was successfully treated with antiviral therapy. Genotyping of all HSV-2-positive samples showed 100% sequence homology for three recipients.

CONCLUSIONS

Donor-derived HSV infection affected two clusters of recipients because of transplantation of organs from a prior organ recipient. HSV should be considered as a possible cause of illness in febrile SOT recipients in the immediate post-transplant period and may cause disseminated disease and re-infection in HSV-2-seropositive recipients. Testing of HSV serology and prophylaxis may be considered in SOT recipients not receiving cytomegalovirus prophylaxis.

Preventive Strategies Against Cytomegalovirus and Incidence of α-Herpesvirus Infections in Solid Organ Transplant Recipients: A Nationwide Cohort Study

We assessed the impact of antiviral preventive strategies on the incidence of herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections in a nationwide cohort of transplant recipients. Risk factors for the development of HSV or VZV infection were assessed by Cox proportional hazards regression. We included 2781 patients (56% kidney, 20% liver, 10% lung, 7.3% heart, 6.7% others). Overall, 1264 (45%) patients received antiviral prophylaxis (ganciclovir or valganciclovir, n = 1145; acyclovir or valacyclovir, n = 138). Incidence of HSV and VZV infections was 28.9 and 12.1 cases, respectively, per 1000 person-years. Incidence of HSV and VZV infections at 1 year after transplant was 4.6% (95% confidence interval [CI] 3.5-5.8) in patients receiving antiviral prophylaxis versus 12.3% (95% CI 10.7-14) in patients without prophylaxis; this was observed particularly for HSV infections (3% [95% CI 2.2-4] versus 9.8% [95% CI 8.4-11.4], respectively). A lower rate of HSV and VZV infections was also seen in donor or recipient cytomegalovirus-positive patients receiving ganciclovir or valganciclovir prophylaxis compared with a preemptive approach. Female sex (hazard ratio [HR] 1.663, p = 0.001), HSV seropositivity (HR 5.198, p < 0.001), previous episodes of rejection (HR 1.95, p = 0.004), and use of a preemptive approach (HR 2.841, p = 0.017) were significantly associated with a higher risk of HSV infection. Although HSV and VZV infections were common after transplantation, antiviral prophylaxis significantly reduced symptomatic HSV infections.

A retrospective study to describe the epidemiology and outcomes of opportunistic infections after abdominal organ transplantation

BACKGROUND

Most epidemiologic studies of opportunistic infections (OI) following abdominal organ transplantation are derived prior to the era of contemporary immunosuppression and prophylaxis. These studies suggest that most OI occur within the first 6 months post transplant.

METHOD

In this single-center, retrospective cohort study, we describe the epidemiology of OI in 359 consecutive abdominal organ transplant recipients, in the era of contemporary prophylaxis practices and alemtuzumab induction in kidney and simultaneous pancreas-kidney transplant recipients.

RESULTS

Ninety patients (25.1%) developed OI, with 53.3% of these occurring beyond 6 months. The most common OI were BK polyomavirus nephropathy (5.0%), cytomegalovirus (10.2%), varicella zoster virus (4.4%), and herpes simplex virus (1.1%), which typically occurred after discontinuation of antiviral prophylaxis, and Clostridium difficile infections (7.8%).

CONCLUSION

OI had no impact on patient or graft survival at 12 months post transplant. In the era of contemporary immunosuppression and prophylaxis, a significant proportion of OI occur beyond 6 months. Additional strategies may be important to reduce the incidence of such late-onset infections.

Herpes Zoster reactivation in patients with chronic hepatitis C under treatment with directly acting antiviral agents: A case series

We report a series of cutaneous Herpes Zoster (HZ) reactivation cases in patients with hepatitis C virus (HCV) infection treated with directly acting antiviral (DAA) agents. Five cases were detected among 2133 treated patients with DAAs at one of the specialized viral hepatitis treatment centers in Egypt. A control group including 2300 age and sex matched HCV patients who were previously treated with pegylated interferon and ribavirin did not show any HZ reactivation reports while on treatment. None of cases had an evidence of immunosuppression or a risk factor for HZ reactivation. The DAAs used regimens were sofosbuvir/daclatasvir in 4 cases and sofosbuvir/simeprevir in one case. HCV clearance with antiviral therapy may bring immune changes causing reactivation of other latent viral infections like HZ. A high index of clinical suspicion may be needed to guarantee early and prompt management of such cases.

Herpesviruses dUTPases: A New Family of Pathogen-Associated Molecular Pattern (PAMP) Proteins with Implications for Human Disease

The human herpesviruses are ubiquitous viruses and have a prevalence of over 90% in the adult population. Following a primary infection they establish latency and can be reactivated over a person's lifetime. While it is well accepted that human herpesviruses are implicated in numerous diseases ranging from dermatological and autoimmune disease to cancer, the role of lytic proteins in the pathophysiology of herpesvirus-associated diseases remains largely understudies. Only recently have we begun to appreciate the importance of lytic proteins produced during reactivation of the virus, in particular the deoxyuridine triphosphate nucleotidohydrolases (dUTPase), as key modulators of the host innate and adaptive immune responses. In this review, we provide evidence from animal and human studies of the Epstein-Barr virus as a prototype, supporting the notion that herpesviruses dUTPases are a family of proteins with unique immunoregulatory functions that can alter the inflammatory microenvironment and thus exacerbate the immune pathology of herpesvirus-related diseases including myalgic encephalomyelitis/chronic fatigue syndrome, autoimmune diseases, and cancer.

Treatment of alpha and beta herpesvirus infections in solid organ transplant recipients

INTRODUCTION

Human herpesviruses frequently cause infections in solid organ transplant (SOT) recipients. Areas covered: We provide an overview of the clinical impact of alpha and beta herpesviruses and highlight the mechanisms of action, pharmacokinetics, clinical indications, and adverse effects of antiviral drugs for the management of herpes simplex virus, varicella zoster virus and cytomegalovirus. We comprehensively evaluated key clinical trials that led to drug approval, and served as the foundation for management guidelines. We further provide an update on investigational antiviral agents for alpha and beta herpesvirus infections after SOT. Expert commentary: The therapeutic armamentarium for herpes infections is limited by the emergence of drug resistance. There have been major efforts for discovery of new drugs against these viruses, but the results of early-phase clinical trials have been less than encouraging. We believe, however, that more antiviral drug options are needed given the adverse side effects associated with current antiviral agents, and the emergence of drug-resistant virus populations in SOT recipients. Likewise, optimized use and strategies are needed for existing and novel antiviral drugs against alpha and beta-herpesviruses in SOT recipients.

The mystery of the Hawaii liver disease cluster in summer 2013: A pragmatic and clinical approach to solve the problem

BACKGROUND AND AIM

In the fall of 2013, the US Centers for Disease Control and Prevention (CDC) published a preliminary report on a cluster of liver disease cases that emerged in Hawaii in the summer 2013. This report claimed a temporal association as sufficient evidence that OxyELITE Pro (OEP), a dietary supplement (DS) mainly for weight loss, was the cause of this mysterious cluster. However, the presented data were inconsistent and required a thorough reanalysis.

MATERIAL AND METHODS

To further investigate the cause(s) of this cluster, we critically evaluated redacted raw clinical data of the cluster patients, as the CDC report received tremendous publicity in local and nationwide newspapers and television. This attention put regulators and physicians from the medical center in Honolulu that reported the cluster, under enormous pressure to succeed, risking biased evaluations and hasty conclusions.

RESULTS

We noted pervasive bias in the documentation, conclusions, and public statements, also poor quality of case management. Among the cases we reviewed, many causes unrelated to any DS were evident, including decompensated liver cirrhosis, acute liver failure by acetaminophen overdose, acute cholecystitis with gallstones, resolving acute hepatitis B, acute HSV and VZV hepatitis, hepatitis E suspected after consumption of wild hog meat, and hepatotoxicity by acetaminophen or ibuprofen. Causality assessments based on the updated CIOMS scale confirmed the lack of evidence for any DS including OEP as culprit for the cluster.

CONCLUSIONS

Thus, the Hawaii liver disease cluster is now best explained by various liver diseases rather than any DS, including OEP.

The Honolulu Liver Disease Cluster at the Medical Center: Its Mysteries and Challenges

In 2013, physicians at the Honolulu Queen’s Medical Center (QMC) noticed that seven liver disease patients reported the use of OxyELITE Pro (OEP), a widely consumed dietary supplement (DS). Assuming a temporal association between OEP use and disease, they argued that OEP was the cause of this mysterious cluster. Subsequent reexamination, however, has revealed that this QMC cohort is heterogeneous and not a cluster with a single agent causing a single disease. It is heterogeneous because patients used multiple DS’s and drugs and because patients appeared to have suffered from multiple liver diseases: liver cirrhosis, liver failure by acetaminophen, hepatotoxicity by non-steroidal antiinflammatory drugs (NSAIDs), resolving acute viral hepatitis by hepatitis B virus (HBV), herpes simplex virus (HSV), and varicella zoster virus (VZV), and suspected hepatitis E virus (HEV). Failing to exclude these confounders and to consider more viable diagnoses, the QMC physicians may have missed specific treatment options in some of their patients. The QMC physicians unjustifiably upgraded their Roussel Uclaf Causality Assessment Method (RUCAM) causality scores so that all patients would appear to be “probable” for OEP. However, subsequent RUCAM reassessments by our group demonstrated a lack of causality for OEP in the evaluated QMC cases. The QMC’s questionable approaches explain the extraordinary accumulation of suspected OEP cases at the QMC in Hawaii as single place, whereas similar cohorts were not published by any larger US liver center, substantiating that the problem is with the QMC. In this review article, we present and discuss new case data and critically evaluate upcoming developments of problematic regulatory assessments by the US Centers for Disease Control and Prevention (CDC), the Hawaii Department of Health (HDOH), and the Food and Drug Administration (FDA), as based on invalid QMC conclusions, clarifying now also basic facts and facilitating constructive discussions.

Renal allograft re-use and herpetic re-infection

A middle-aged man received a kidney transplant from a deceased multi-organ donor. The recipient suffered cardiac arrest several days post-operatively and sustained hypoxic brain injury and was declared brain dead. Following the family's consent, the allograft kidney was retrieved and re-transplanted into a man with end-stage renal failure secondary to reflux nephropathy. The liver was not transplanted due to suspicion of fatty changes based on macroscopic appearance. After transplantation of other organs, liver histology revealed coagulative parenchymal necrosis with nuclear inclusions and moderate parenchymal cholestasis, suggestive of herpes viral hepatitis. Renal implantation biopsy showed histiocytes with enlarged nuclei containing viral inclusions in the capsular fibrous tissue, with positive immunostaining for herpes simplex virus (HSV). Anti-viral therapy was commenced immediately after obtaining histological evidence of donor HSV infection. Our recipient had pre-formed immunoglobulin G antibodies to HSV-1 and HSV-2, and was immunoglobulin M negative pre-transplant. HSV viraemia was detected day 5 post-transplant with a viral load of 7688 copies/mL by polymerase chain reaction assay. The recipient completed a 30 day course of intravenous ganciclovir before switching to oral valganciclovir as standard cytomegalovirus prophylaxis. The HSV polymerase chain reaction became undetectable on day 7 of intravenous ganciclovir and has remained undetectable. The patient remains well 9 months post-transplant with an estimated glomerular filtration rate of 61 mL/min per 1.73 m(2). Although renal allograft re-use has been shown to be technically possible with a good outcome in this recipient, this does raise issues including assessment of allografts that have undergone repeated severe ischaemic insults and the potential of transmission of infections.

Incidence and risk factors for herpes zoster in patients undergoing liver transplantation

BACKGROUND

Herpes zoster (HZ) is the most common manifestation of latent varicella zoster virus reactivation, which occurs naturally as a result of aging or in immunocompromised patients. Solid organ transplant recipients are at increased risk for HZ owing to their chronic immunosuppression. Although several reports investigated risk factors for the development of HZ in heart or renal transplantation, data in liver transplantation (LT) are limited.

METHODS

We evaluated clinical data retrospectively in 377 adult patients undergoing LT between January 2005 and December 2012 in our institution. We analyzed the incidence rate of HZ and the standardized incidence ratio (SIR) by comparing with the general Japanese population. We additionally investigated risk factors for HZ after LT.

RESULTS

HZ developed in 27 (7.16%) of the 377 patients after LT. The incidence rate of HZ after LT was 17.83 per 1000 person-years, which was significantly higher than in the general Japanese population (SIR = 4.61; 95% confidence interval [CI], 4.13-5.14). Multivariate analysis showed that older age (hazard ratio [HR] = 3.95; P < 0.001) and exposure to mycophenolate mofetil (HR = 3.03; P = 0.007) were independent risk factors for HZ after LT.

CONCLUSIONS

This is the first and largest study, to our knowledge, to investigate the incidence rate of HZ and risk factors for development of HZ after LT in the Japanese population. Further investigations to focus on immunosuppressive regimens to reduce the risk for HZ incidence in this high-risk population could establish a new protocol of immunosuppression after LT.

Incidence and risk factors of herpes zoster among adult renal transplant recipients receiving universal antiviral prophylaxis

Background

Herpes zoster (HZ) is a significant cause of morbidity and complications in adult renal transplant recipients. We determined the incidence, complications and risk factors for the development of HZ after renal transplantation in a setting using universal antiviral prophylaxis.

Methods

The medical files of all adult renal transplants, performed between 2004 and 2008, were retrospectively reviewed to assess the clinical characteristics and risk factors of HZ. Incident cases of HZ were determined and the probability of developing post-transplant HZ for all subjects was calculated using the Kaplan Meier method. A multivariable Cox proportional hazards model was applied to assess the risk factors associated with the development of HZ.

Results

A total of 450 patients were eligible with a median follow up of 38 months. Twenty nine subjects (6.4 %) developed HZ, the median time to onset was 18 months, only three of them (10.3 %) required hospitalization, and none developed disseminated or visceral disease and death directly attributed to zoster. However, high rates of post-herpetic neuralgia (48.7 %) were observed. Overall incidence was calculated at 20.6 cases per 1000 patient-years of follow-up. Following multivariate analysis, increased age ≥ 60 years old, positive pre-transplant history of varicella related disease and administration of rejection treatment conferred an increased risk of 4.00-fold (CI: 1.79- 8.92), 16.00-fold (CI: 4.62- 55.52), and 5.57-fold (CI: 1.56- 19.84) respectively, for the development of post-transplant zoster.

Conclusions

HZ remains a common complication after renal transplantation in adults under current immunosuppession protocols and universal antiviral prophylaxis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1038-1) contains supplementary material, which is available to authorized users.

Cooperation between Epstein-Barr virus immune evasion proteins spreads protection from CD8+ T cell recognition across all three phases of the lytic cycle

CD8+ T cell responses to Epstein-Barr virus (EBV) lytic cycle expressed antigens display a hierarchy of immunodominance, in which responses to epitopes of immediate-early (IE) and some early (E) antigens are more frequently observed than responses to epitopes of late (L) expressed antigens. It has been proposed that this hierarchy, which correlates with the phase-specific efficiency of antigen presentation, may be due to the influence of viral immune-evasion genes. At least three EBV-encoded genes, BNLF2a, BGLF5 and BILF1, have the potential to inhibit processing and presentation of CD8+ T cell epitopes. Here we examined the relative contribution of these genes to modulation of CD8+ T cell recognition of EBV lytic antigens expressed at different phases of the replication cycle in EBV-transformed B-cells (LCLs) which spontaneously reactivate lytic cycle. Selective shRNA-mediated knockdown of BNLF2a expression led to more efficient recognition of immediate-early (IE)- and early (E)-derived epitopes by CD8+ T cells, while knock down of BILF1 increased recognition of epitopes from E and late (L)-expressed antigens. Contrary to what might have been predicted from previous ectopic expression studies in EBV-negative model cell lines, the shRNA-mediated inhibition of BGLF5 expression in LCLs showed only modest, if any, increase in recognition of epitopes expressed in any phase of lytic cycle. These data indicate that whilst BNLF2a interferes with antigen presentation with diminishing efficiency as lytic cycle progresses (IE>E>>L), interference by BILF1 increases with progression through lytic cycle (IE Collapse

Key Words Collapse

MESH Headings

• Antigen Presentation/immunology
• Blotting, Western
• CD8-Positive T-Lymphocytes/immunology
• Deoxyribonucleases/immunology
• Epstein-Barr Virus Infections/immunology
• Gene Knockdown Techniques
• Herpesvirus 4, Human/immunology
• Humans
• Immune Evasion/immunology
• Real-Time Polymerase Chain Reaction
• Receptors, G-Protein-Coupled/immunology
• Viral Matrix Proteins/immunology
• Viral Proteins/immunology

Collapse

Grants

• 15032 Cancer Research UK
• MR/J002046/1 Medical Research Council
• G0901755 Medical Research Council
• C5575/A15032 Cancer Research UK

Collapse

Affiliation(s)

Laura L. Quinn School of Cancer Sciences and Centre for Human Virology, University of Birmingham College of Medical and Dental Sciences, Edgbaston, Birmingham, United Kingdom
Jianmin Zuo School of Cancer Sciences and Centre for Human Virology, University of Birmingham College of Medical and Dental Sciences, Edgbaston, Birmingham, United Kingdom
Rachel J. M. Abbott School of Cancer Sciences and Centre for Human Virology, University of Birmingham College of Medical and Dental Sciences, Edgbaston, Birmingham, United Kingdom
Claire Shannon-Lowe School of Cancer Sciences and Centre for Human Virology, University of Birmingham College of Medical and Dental Sciences, Edgbaston, Birmingham, United Kingdom
Rosemary J. Tierney School of Cancer Sciences and Centre for Human Virology, University of Birmingham College of Medical and Dental Sciences, Edgbaston, Birmingham, United Kingdom
Andrew D. Hislop School of Cancer Sciences and Centre for Human Virology, University of Birmingham College of Medical and Dental Sciences, Edgbaston, Birmingham, United Kingdom
Martin Rowe School of Cancer Sciences and Centre for Human Virology, University of Birmingham College of Medical and Dental Sciences, Edgbaston, Birmingham, United Kingdom

Collapse

Prospects and perspectives for development of a vaccine against herpes simplex virus infections

Herpes simplex viruses 1 and 2 are human pathogens that lead to significant morbidity and mortality in certain clinical settings. The development of effective antiviral medications, however, has had little discernible impact on the epidemiology of these pathogens, largely because the majority of infections are clinically silent. Decades of work have gone into various candidate HSV vaccines, but to date none has demonstrated sufficient efficacy to warrant licensure. This review examines developments in HSV immunology and vaccine development published since 2010, and assesses the prospects for improved immunization strategies that may result in an effective, licensed vaccine in the near future.

Immunization after kidney transplantation-what is necessary and what is safe?

Many transplant recipients are not protected against vaccine-preventable illnesses, primarily because vaccination is still an underutilized tool both before and after transplantation. This missed opportunity for protection can result in substantial morbidity, graft loss and mortality. Immunization strategies should be formulated early in the course of renal disease to maximize the likelihood of vaccine-induced immunity, particularly as booster or secondary antibody responses are less affected by immune compromise than are primary or de novo antibody responses in naive vaccine recipients. However, live vaccines should be avoided in immunocompromised hosts. Although some concern has been raised regarding increased HLA sensitization after vaccination, no clinical data to suggest harm currently exists; overall, non-live vaccines seem to be immunogenic, protective and safe. In organ transplant recipients, some vaccines are indicated based on specific risk factors and certain vaccines, such as hepatitis B, can protect against donor-derived infection. Vaccines given to close contacts of renal transplant recipients can provide an additional layer of protection against infectious diseases. In this article, optimal vaccination of adult transplant recipients, including safety, efficacy, indication and timing, is reviewed.