Long-term acyclovir for prevention of varicella zoster virus disease after allogeneic hematopoietic cell transplantation--a randomized double-blind placebo-controlled study

Studies with herpes zoster vaccines in immune compromised patients

INTRODUCTION

The active component of the herpes zoster vaccine (ZVL), licensed for people ≥50 years of age, is a live attenuated varicella-zoster virus. ZVL is contraindicated for immune compromised individuals, with limited regard to the degree of immunosuppression. Areas covered: This review evaluates phase I and II and observational studies for ZVL, and published reports of the off-label use of ZVL, for conditions and therapies for which investigators considered the risk-benefit for using ZVL to be favorable. It also discusses exploratory trials of ZVL for additional immune compromising conditions, and summarizes clinical guidelines from many countries and professional societies that are based upon recent investigations. Studies in immune compromised patients of investigational vaccines that do not contain live virus are reviewed. Expert commentary: It is likely that past and ongoing research with ZVL will define immune compromising diseases and/or therapies for which the risk-benefit for using ZVL vaccine is favorable. The main variables to consider in this assessment in immune compromised patients are safety, immunogenicity, protection against herpes zoster, and persistence of protection. Vaccination against herpes zoster prior to suppressing immunity is an important clinical strategy, although efficacy of this approach has not been evaluated in a clinical trial.

Prophylactic Measures During Induction for Acute Myeloid Leukemia

PURPOSE OF REVIEW

Improved management of infectious complications of acute myeloid leukemia (AML) has contributed substantially to the success of care over the past half century. An important approach to reducing infectious complications during the induction period of chemotherapy involves the use of prophylactic antibacterial, antiviral, and antifungal agents targeting likely pathogens.

RECENT FINDINGS

There is not a one-size-fits-all approach to prophylaxis; every patient undergoing induction therapy should be evaluated individually and within the context of local microbiologic epidemiology and host risk factors. Pharmacologic and non-pharmacologic interventions as well as novel diagnostic platforms can help mitigate the risk of life-threatening infection in patients with AML who undergo induction chemotherapy.

Herpes Simplex Virus and Varicella-Zoster Virus

The most common specimens from immunocompromised patients that are analyzed for detection of herpes simplex virus (HSV) or varicella-zoster virus (VZV) are from skin lesions. Many types of assays are applicable to these samples, but some, such as virus isolation and direct fluorescent antibody testing, are useful only in the early phases of the lesions. In contrast, nucleic acid (NA) detection methods, which generally have superior sensitivity and specificity, can be applied to skin lesions at any stage of progression. NA methods are also the best choice, and sometimes the only choice, for detecting HSV or VZV in blood, cerebrospinal fluid, aqueous or vitreous humor, and from mucosal surfaces. NA methods provide the best performance when reliability and speed (within 24 hours) are considered together. They readily distinguish the type of HSV detected or the source of VZV detected (wild type or vaccine strain). Nucleic acid detection methods are constantly being improved with respect to speed and ease of performance. Broader applications are under study, such as the use of quantitative results of viral load for prognosis and to assess the efficacy of antiviral therapy.

National Institutes of Health Hematopoietic Cell Transplantation Late Effects Initiative: The Immune Dysregulation and Pathobiology Working Group Report

Immune reconstitution after hematopoietic stem cell transplantation (HCT) beyond 1 year is not completely understood. Many transplant recipients who are free of graft-versus-host disease (GVHD) and not receiving any immunosuppression more than 1 year after transplantation seem to be able to mount appropriate immune responses to common pathogens and respond adequately to immunizations. However, 2 large registry studies over the last 2 decades seem to indicate that infection is a significant cause of late mortality in some patients, even in the absence of concomitant GVHD. Research on this topic is particularly challenging for several reasons. First, there are not enough long-term follow-up clinics able to measure even basic immune parameters late after HCT. Second, the correlation between laboratory measurements of immune function and infections is not well known. Third, accurate documentation of infectious episodes is notoriously difficult. Finally, it is unclear what measures can be implemented to improve the immune response in a clinically relevant way. A combination of long-term multicenter prospective studies that collect detailed infectious data and store samples as well as a national or multinational registry of clinically significant infections (eg, vaccine-preventable severe infections, opportunistic infections) could begin to address our knowledge gaps. Obtaining samples for laboratory evaluation of the immune system should be both calendar and eventdriven. Attention to detail and standardization of practices regarding prophylaxis, diagnosis, and definitions of infections would be of paramount importance to obtain clean reliable data. Laboratory studies should specifically address the neogenesis, maturation, and exhaustion of the adaptive immune system and, in particular, how these are influenced by persistent alloreactivity, inflammation, and viral infection. Ideally, some of these long-term prospective studies would collect information on long-term changes in the gut microbiome and their influence on immunity. Regarding enhancement of immune function, prospective measurement of the response to vaccines late after HCT in a variety of clinical settings should be undertaken to better understand the benefits as well as the limitations of immunizations. The role of intravenous immunoglobulin is still not well defined, and studies to address it should be encouraged.

Varicella zoster virus infection after allogeneic hematopoietic cell transplantation in children using a relatively short duration of acyclovir prophylaxis: A retrospective study

Although acyclovir prophylaxis against varicella zoster virus (VZV) infection for ≥1 year is recommended after allogeneic hematopoietic cell transplantation (HCT), the emergence of acyclovir-resistant viruses and adverse drug effects cannot be ignored. We investigated the cumulative incidence of VZV infection after allogeneic HCT in children receiving a shorter duration of acyclovir prophylaxis than recommended and evaluated the appropriateness of the short duration of acyclovir prophylaxis.Medical records of 217 children who received allogeneic HCT were retrospectively reviewed until a median of 25 months (range = 1-59 months) after HCT. Acyclovir prophylaxis was given for a median of 9 weeks (range = 3-24 weeks) after HCT.VZV infection was diagnosed in 33 (15.2%) children at a median time of 5 months (range = 2-41 months) after HCT. The 1-year and 2-year cumulative incidences of VZV infection after allogeneic HCT were 11.2% and 15.5%, respectively. These incidences were between the previously reported 1-year incidence of 25% to 30% in patients not receiving prophylaxis and 1-year incidence of 4% to 5% in patients receiving ≥1 year duration of prophylaxis. Male sex and older age were significantly associated with VZV infection after allogeneic HCT. Only 1 chickenpox patient experienced severe complications because of VZV infection, and there were no deaths attributable to VZV infection.In conclusion, a shorter duration of acyclovir prophylaxis may be appropriate for children receiving allogeneic HCT, based on the rare occurrence of severe complications because of VZV infection and the expected discomfort because of daily oral medication for a long time.

Late effects of blood and marrow transplantation

Hematopoietic cell transplantation is a curative treatment for a variety of hematologic diseases. Advances in transplantation technology have reduced early transplant-related mortality and expanded application of transplantation to older patients and to a wider variety of diseases. Management of late effects after transplantation is increasingly important for a growing number of long-term survivors that is estimated to be half a million worldwide. Many studies have shown that transplant survivors suffer from significant late effects that adversely affect morbidity, mortality, working status and quality of life. Late effects include diseases of the cardiovascular, pulmonary, and endocrine systems, dysfunction of the thyroid gland, gonads, liver and kidneys, infertility, iron overload, bone diseases, infection, solid cancer, and neuropsychological effects. The leading causes of late mortality include recurrent malignancy, lung diseases, infection, secondary cancers and chronic graft-versus-host disease. The aim of this review is to facilitate better care of adult transplant survivors by summarizing accumulated evidence, new insights, and practical information about individual late effects. Further research is needed to understand the biology of late effects allowing better prevention and treatment strategies to be developed.

Antiviral prophylaxis for preventing herpes zoster in hematopoietic stem cell transplant recipients: A systematic review and meta-analysis

The optimal duration of prophylaxis for the varicella-zoster virus following hematopoietic stem cell transplantation (HSCT) remains unclear. The purpose of this study was to systematically review the available literature to determine the optimal duration of antiviral prophylaxis for preventing herpes zoster (HZ) in allogeneic and autologous HSCT recipients. The MEDLINE and EMBASE databases were searched to identify relevant studies. The relative risk (RR) of HZ was calculated using fixed effects or random effects models depending on heterogeneity across the included studies. We analyzed six observational studies comprising a total of 3420 patients. In all HSCT recipients, the overall incidence of HZ in the prophylaxis group and the control group was 7.8% and 25.6%, respectively, with a pooled RR of 0.31 (95% CI, 0.26-0.37). The incidence of HZ in the subgroup wherein prophylaxis was given for at least 1 year and in the subgroup wherein prophylaxis was given for less than 1 year was 2.1% and 15.4%, respectively, with a pooled RR of 0.23 (95% CI, 0.04-1.39). Taken together, our results demonstrate that antiviral prophylaxis can significantly reduce HZ in HSCT recipients, and suggests that long-term prophylaxis given for at least 1 year may be recommended for better preventive effects.

Herpes Zoster in Autologous Hematopoietic Cell Transplant Recipients in the Era of Acyclovir or Valacyclovir Prophylaxis and Novel Treatment and Maintenance Therapies

The epidemiology of herpes zoster (HZ) in contemporary autologous hematopoietic cell transplant (HCT) recipients, and the impact of acyclovir (ACV)/valacyclovir (VACV) prophylaxis, is not well described. In this observational study from 2002 to 2010, we retrospectively identified 1000 varicella zoster virus (VZV)-seropositive autologous HCT recipients with up to 5 years of follow-up. The incidence of HZ and use of ACV/VACV prophylaxis were determined through review of medical records and mailed questionnaires. Risk factors for HZ were determined by multivariable Cox regression. Over a period of 5 years after autologous HCT, 194 patients developed at least 1 HZ episode, with a cumulative incidence of 21%; 159 of 194 (82%) were not on prophylaxis at the time of HZ. A second episode of HZ occurred in 31 of 194 (16%) patients. Patients taking ACV/VACV had reduced risk for HZ (adjusted hazard ratio [aHR], .59; 95% confidence interval [CI], .37 to .91), whereas those older than the median age (≥55.5 years) had increased risk (aHR, 1.42; 95% CI, 1.05 to 1.9). Disseminated VZV was reported in 8% and postherpetic neuralgia in 13% of patients. We demonstrate a high burden of HZ late after autologous HCT, despite long-term antiviral prophylaxis. Improved prevention strategies are needed to provide sustained protection against HZ after autologous HCT.

Zoster prophylaxis after allogeneic hematopoietic cell transplantation using acyclovir/valacyclovir followed by vaccination

Varicella zoster virus (VZV) disease (usually cutaneous zoster) occurs frequently after hematopoietic cell transplantation (HCT), and postherpetic neuralgia (PHN) results in poor quality of life. The optimal prophylaxis of VZV disease/PHN has not been established. At our center, before 2008, VZV prophylaxis consisted of ∼1 year of post-HCT acyclovir/valacyclovir ("old strategy"), whereas post-2008 prophylaxis consisted of 2 years of acyclovir/valacyclovir followed by immunization using varicella vaccine ("new strategy"). We performed a retrospective study comparing the cumulative incidence of VZV disease and PHN among patients who completed the old strategy (n = 153) vs the new strategy (n = 125). Patients who completed the old strategy had a significantly higher cumulative incidence of VZV disease (33% vs 17% at 5 years, P ≤ .01) and PHN (8% vs 0% at 5 years, P = .02). In conclusion, VZV prophylaxis with 2 years of acyclovir/valacyclovir followed by vaccination appears to result in a low incidence of VZV disease and may eliminate PHN.

Predicting risk factors for varicella zoster virus infection and postherpetic neuralgia after hematopoietic cell transplantation using ordered logistic regression analysis

To identify risk factors for varicella zoster virus (VZV) infection and postherpetic neuralgia (PHN) after hematopoietic cell transplantation (HCT), we conducted a retrospective chart review of 163 consecutive patients who underwent HCT between November 2004 and July 2014. Overall, the male/female (M/F) ratio was 80/83, median age at HCT was 54 (range 15-69) years, and autologous/allogeneic HCT (auto/allo-HCT) ratio was 71/92. Forty-four patients [M/F, 25/19; median age, 57 (range: 16-68) years; auto/allo-HCT, 26/18] developed VZV infection after HCT. All cases were successfully treated with acyclovir (ACV) or valacyclovir, and there was no VZV-related death. Nine (20%) of the 44 patients [M/F, 5/4; median age, 58 (range: 21-63) years; auto/allo-HCT, 7/2] developed PHN after resolution of zoster. Multivariate ordered logistic analysis identified receiving immunosuppressive therapy at the cessation of ACV [odds ratio (OR) = 74.53; 95% confidence interval (CI) = 6.99-794.32; P = 0.0004] as a risk factor for VZV infection and PHN in allo-HCT recipients. However, in auto-HCT recipients, only advanced age was identified as a risk factor (OR = 1.06, 95% CI = 1.002-1.127, P = 0.0429). Our findings indicate receiving immunosuppressive therapy at the cessation of ACV is a significant risk factor for allo-HCT recipients, while advanced age is a significant risk factor for auto-HCT recipients.

T Cell Immunity to Varicella-Zoster Virus in the Setting of Advanced HIV and Multiple Varicella-Zoster Virus Recurrences

A woman presented with at least four manifestations of varicella-zoster virus (VZV) infection, including central nervous system vasculitis, during her first 2 years of HIV infection. We evaluated her CD4 T cell responses to VZV given the infrequency with which multiple recurrences of VZV occurred, especially following immune reconstitution on antiretroviral therapy.

Brincidofovir treatment of acyclovir-resistant disseminated varicella zoster virus infection in an immunocompromised host

Brincidofovir (BCV) is a broad-spectrum antiviral agent active in vitro against double-stranded DNA viruses including herpesviruses, adenoviruses, polyomaviruses, and poxviruses. We report successful BCV use in management of disseminated acyclovir- and cidofovir-resistant varicella zoster virus in an immunocompromised hematopoietic stem cell transplant patient with chronic graft-versus-host disease who was intolerant to foscarnet.

Infectious diseases in allogeneic haematopoietic stem cell transplantation: prevention and prophylaxis strategy guidelines 2016

Infectious complications after allogeneic haematopoietic stem cell transplantation (allo-HCT) remain a clinical challenge. This is a guideline provided by the AGIHO (Infectious Diseases Working Group) of the DGHO (German Society for Hematology and Medical Oncology). A core group of experts prepared a preliminary guideline, which was discussed, reviewed, and approved by the entire working group. The guideline provides clinical recommendations for the preventive management including prophylactic treatment of viral, bacterial, parasitic, and fungal diseases. The guideline focuses on antimicrobial agents but includes recommendations on the use of vaccinations. This is the updated version of the AGHIO guideline in the field of allogeneic haematopoietic stem cell transplantation utilizing methods according to evidence-based medicine criteria.

Herpes zoster after autologous hematopoietic stem cell transplantation

BACKGROUND

The autologous hematopoietic stem cell transplantation procedure involves immunosuppression of the patient. Thus, the patient has an elevated risk for several diseases, such as infections with the varicella-zoster virus. Prevention protocols have been proposed based on the use of acyclovir from the first day of conditioning, and maintaining this drug for 30-100 days after the procedure or for as much as one year. The objective of this work was to evaluate the incidence of herpes zoster after autologous transplantations related to the early suspension of acyclovir.

METHODS

A retrospective study was carried out based on the collection of data from 231 medical records of transplant patients in the Bone Marrow Transplant Unit of the teaching hospital of the Universidade Federal de Juiz de Fora in the period between 2004 and 2014.

RESULTS

Fourteen (6.1%) patients had herpes zoster in the post-transplant period on average within six months of the procedure. Patients with multiple myeloma (64.3%) were the most affected. There was a statistically significant difference in the age of the patients, with older individuals having a greater chance of developing the infection (p-value=0.002). There were no significant differences for the other variables analyzed.

CONCLUSION

The early suspension of acyclovir can be safe in patients who receive autologous hematopoietic stem cell transplants. However some groups may benefit from extended prophylaxis with acyclovir, particularly older patients and patients with multiple myeloma.

Addition of varicella zoster virus-specific T cells to cytomegalovirus, Epstein-Barr virus and adenovirus tri-specific T cells as adoptive immunotherapy in patients undergoing allogeneic hematopoietic stem cell transplantation

BACKGROUND AIMS

Virus-specific T-cell immunotherapy is emerging as a promising management strategy for virus infections in patients after hematopoietic stem cell transplant (HSCT). Here we present outcomes of 10 adult patients who received multi-virus-specific T cells prophylactically after HSCT.

METHODS

Donor-derived cytomegalovirus (CMV)-, Epstein-Barr virus (EBV)-, adenoviral- and varicella zoster virus (VZV)-specific T cells were generated in a single culture and administered to HSCT patients at a dose of 2 × 10(7)/m(2) virus-specific T cells at a median of 63 days post-transplant. Patients were monitored for 12 months for evidence of viral reactivation and graft-versus-host disease.

RESULTS

There was no acute infusion-related toxicity. Six patients developed CMV reactivation after T-cell infusion with a median peak CMV DNA titer of 600 copies per milliliter, and 1 received CMV-specific pharmacotherapy post-infusion. No EBV, adenoviral or VZV reactivation or disease was reported. Using interferon-γ Elispot analysis on post-infusion samples, we identified anti-viral immunity against all viruses including VZV. Three patients (30%) developed grade II-IV acute graft-versus-host disease.

CONCLUSIONS

This is the first description of the use of a multi-virus-specific T-cell product containing cells specific for VZV after allogeneic HSCT. The T-cell product appears safe in the setting of HSCT and confirms our previous findings regarding CMV control and treatment. A larger study with longer follow-up is required to determine the efficacy of VZV-specific T cells given prophylactically in controlling episodes of herpes zoster and disseminated varicella infection after cessation of prophylactic anti-viral treatment.

Risks and Epidemiology of Infections After Hematopoietic Stem Cell Transplantation

Infections following HCT are frequently related to risk factors caused by the procedure itself. Neutropenia and mucositis predispose to bacterial infections. Prolonged neutropenia increases the likelihood of invasive fungal infection. GVHD and its treatment create the most important easily identifiable risk period for a variety of infectious complications, particularly mold infections. Profound, prolonged T cell immunodeficiency, present after T cell-depleted or cord blood transplants, is the main risk factor for viral problems like disseminated adenovirus disease or EBV-related posttransplant lymphoproliferative disorder.

Zeroing in on zoster: A tale of many disorders produced by one virus

While herpes zoster infection has been recognized since antiquity, chickenpox (varicella) was confused with smallpox until the 1800s, when both illnesses became better understood. In the 20th century, varicella zoster virus (VZV) was shown to cause varicella upon primary (first-time) infection and herpes zoster (shingles) after reactivation of latent VZV. Scientific progress over the past 50 years has rapidly advanced the understanding and prevention of disease produced by VZV. Combined imaging and virological studies continue to reveal the protean neurological, ocular and visceral disorders produced by VZV.

The yield of monitoring for HSV and VZV viremia in pediatric hematopoietic stem cell transplant patients

Reactivation of HSV and VZV is common following HSCT. Consensus guidelines do not support the use of routine screening for viremia following HSCT in adults, but no such clear guidelines exist in pediatrics. In our center, routine practice was to screen patients weekly for HSV and VZV viremia until engraftment in autologous transplant patients and up to day +100 in allogeneic transplant patients. We conducted a retrospective study of over 500 patients to establish whether this screening identified any patients with HSV or VZV viremia who would not have been identified by clinical signs or symptoms. Over a 4.5-yr period, routine screening identified three cases of HSV viremia and one case of VZV viremia. Two patients had persistent, unexplained fever and two patients had skin or mucosal lesions suggestive of HSV/VZV. We conclude that routine screening for HSV and VZV viremia in pediatric HSCT patients has a very low yield and that viremia can be reliably identified by targeted testing in patients with vesicular skin lesions, oral or genital ulceration, unexplained fever, neurological symptoms, or unexplained abnormal liver transaminases.

Prevention of viral infections in patients with multiple myeloma: the role of antiviral prophylaxis and immunization

Viral infections are a major cause of morbidity and mortality in patients with myeloma. Over the last decade, treatment of myeloma has undergone a paradigm shift with the use of immunomodulatory drugs, proteasome inhibitors and autologous stem cell transplantation, resulting in changes to risk periods and risk factors for viral infection. Viral infections affecting this patient group fall broadly into reactivation of latent viral infections (e.g., varicella zoster and hepatitis B) and acquisition of acute viral respiratory infections. The periods following autologous stem cell transplantation and progressive disease are identified as increased risk for viral infections. This review focuses on evidence-based prevention strategies for key viral infections, particularly approaches to prophylaxis and immunization. Recommended prevention strategies are summarized using a risk-stratified approach. Further studies evaluating preventative measures for newly identified risk periods are required.

A Japanese single-hospital observational trial with a retrospective case-control analysis of varicella zoster virus reactivation after autologous peripheral blood stem cell transplantation

BACKGROUND

Varicella zoster virus (VZV) reactivation following hematopoietic stem cell transplantation (SCT) is common. To help reduce its incidence and to identify predictive factors for VZV reactivation after autologous SCT (auto-SCT), we conducted a retrospective analysis in patients with hematologic malignancy at our hospital.

METHODS

We conducted a single-hospital observational trial with a retrospective case-control analysis of post-auto-SCT VZV reactivation in patients with malignant lymphoma (ML) and multiple myeloma (MM) between January 2001 and December 2010, in the Department of Hematology at our hospital. First, we analyzed the cumulative incidence of VZV reactivation during the post-SCT period. Second, we conducted a case-control analysis to identify the risk factors for VZV reactivation within 1 year after SCT. Univariate analyses were performed using Fisher's exact test for categorical variables. A multivariable model and logistic regression were used to assess the risk factors for VZV reactivation.

RESULTS

We included 97 patients in this study. The median duration of follow-up was 1027 days. Forty-two patients experienced VZV reactivation after SCT, while 29 (69.0%) experienced reactivation within 1 year after SCT. The cumulative incidence was 30.7% at 1 year and 51.2% for the total observation period. Multivariate analysis showed that engraftment after day 10 was an independent risk factor for VZV reactivation (P = 0.03).

CONCLUSIONS

Our study showed a high incidence of VZV reactivation in the first year after auto-SCT in ML and MM patients. Patients with delayed engraftment are at high risk for VZV reactivation and should be considered for prolonged VZV prophylaxis.

National Institutes of Health Consensus Development Project on Criteria for Clinical Trials in Chronic Graft-versus-Host Disease: V. The 2014 Ancillary Therapy and Supportive Care Working Group Report

The 2006 National Institutes of Health (NIH) Consensus paper presented recommendations by the Ancillary Therapy and Supportive Care Working Group to support clinical research trials in chronic graft-versus-host disease (GVHD). Topics covered in that inaugural effort included the prevention and management of infections and common complications of chronic GVHD, as well as recommendations for patient education and appropriate follow-up. Given the new literature that has emerged during the past 8 years, we made further organ-specific refinements to these guidelines. Minimum frequencies are suggested for monitoring key parameters relevant to chronic GVHD during systemic immunosuppressive therapy and, thereafter, referral to existing late effects consensus guidelines is advised. Using the framework of the prior consensus, the 2014 NIH recommendations are organized by organ or other relevant systems and graded according to the strength and quality of supporting evidence.

Pretransplant vaccinations in allogeneic stem cell transplantation donors and recipients: an often-missed opportunity for immunoprotection?

Immune deficiency following hematopoietic cell transplantation predisposes the patient to potentially deadly infections. Vaccinations can improve immunity and thus reduce the morbidity and mortality associated with these infections. Over the years different sets of guidelines have been published the most recent by the Infectious Diseases Society of American (IDSA). There is limited evidence that vaccination of donors and/or recipients before transplantation may improve immunity. However, despite the possibility of augmented immunity, there remain logistical, ethical and medical concerns about such a vaccination strategy.

Varicella zoster virus reactivation after autologous SCT is a frequent event and associated with favorable outcome in myeloma patients

The occurrence of varicella zoster virus (VZV) reactivation is increased after allogeneic transplantation, whereas limited data are available for herpes zoster (HZ) after autologous SCT (ASCT). We determined the incidence and the prognostic significance of HZ and its correlation with VZV serology in 191 consecutive myeloma patients undergoing high-dose melphalan chemotherapy with ASCT. We found that VZV reactivation occurred in 57 (30%) patients, in 8.5% during induction and in 21.5% after ASCT peaking at 8 months after ASCT. Disease burden due to HZ was assessed as high or rather high in 70% of the patients. By immune fluorescence and Serion Elisa VZV IgG assessment, 90.8% of all patients had specific anti-VZV antibodies at ASCT. Lower specific antibody titers at transplantation were observed in patients with HZ after ASCT than in those without reactivation (P=0.009). Finally, OS was better in myeloma patients with HZ after ASCT compared with patients without HZ (P=0.007). Our data indicate that VZV reactivation after ASCT is a frequent event carrying a significant disease burden and it is associated with improved survival. Low levels of specific VZV antibodies at ASCT suggest increased vulnerability for VZV reactivation.

Viral infections in acute graft-versus-host disease: a review of diagnostic and therapeutic approaches

BACKGROUND

While immunosuppressive therapy for acute graft-versus-host disease (aGVHD) advances, viral reactivation has been found to be an increasingly common complication in these patients. Dermatologists may often be consulted on inpatient services for evaluation.

OBJECTIVE

We investigated the literature for the role of viral infections in aGVHD and review the current evidence regarding management.

METHODS

Articles in the public domain regarding aGVHD, cytomegalovirus, Epstein-Barr virus, varicella zoster virus, hepatitis viruses, parvovirus B19, and respiratory viruses were included.

RESULTS

Dermatologic findings vary between different viral antigens, and some infections may be a marker for the development of aGVHD or worsen prognosis.

LIMITATIONS

The heterogeneous cohorts of the studies reviewed often preclude direct comparison between results.

CONCLUSION

The relationship between viral reactivation and aGVHD may be bidirectional and is worthy of further exploration. Additional studies are needed to determine appropriate prophylaxis and treatment.

Valganciclovir for the prevention of complications of late cytomegalovirus infection after allogeneic hematopoietic cell transplantation: a randomized trial

BACKGROUND

Optimal prevention of late cytomegalovirus (CMV) disease is poorly defined.

OBJECTIVE

To compare valganciclovir prophylaxis with polymerase chain reaction-guided preemptive therapy.

DESIGN

Randomized, double-blind trial. (ClinicalTrials.gov: NCT00016068).

SETTING

Multicenter trial.

PATIENTS

184 recipients of hematopoietic cell transplantation (HCT) who were at high risk for late CMV disease (95 patients received valganciclovir and 89 received placebo).

INTERVENTION

6 months of valganciclovir (900 mg/d) or placebo. Patients with polymerase chain reaction positivity at 1000 copies/mL or greater or a 5-fold increase over baseline were treated with ganciclovir or valganciclovir (5 mg/kg or 900 mg twice daily, respectively).

MEASUREMENTS

The composite primary end point was death, CMV disease, or other invasive infections by 270 days after HCT. Secondary end points were CMV disease, CMV DNAemia, death, other infections, resource utilization, ganciclovir resistance, quality of life, immune reconstitution, and safety.

RESULTS

The primary composite outcome occurred in 20% of valganciclovir recipients versus 21% of placebo-preemptive therapy recipients (treatment difference, -0.01 [95% CI, -0.13 to 0.10]; P = 0.86). There was no difference in the primary end point or its components 640 days after HCT. The incidence of a CMV DNAemia level of 1000 copies/mL or greater or a 5-fold increase over baseline was reduced in the valganciclovir group (11% vs. 36%; P < 0.001). Neutropenia was not significantly different at the absolute neutrophil count of less than 0.5 × 109 cells/L (P = 0.57); however, more patients received hematopoietic growth factors in the valganciclovir group (25.3% vs. 12.4%; P = 0.026). No significant differences were seen in other secondary outcomes.

LIMITATION

Some high-risk patients were not included.

CONCLUSION

Valganciclovir prophylaxis was not superior in reducing the composite end point of CMV disease, invasive bacterial or fungal disease, or death when compared with polymerase chain reaction-guided preemptive therapy. Both strategies performed similarly with regard to most clinical outcomes.

PRIMARY FUNDING SOURCE

Roche Laboratories.

Varicella zoster virus encephalomyelitis as a late complication following haematopoietic stem cell transplantation

Varicella zoster virus (VZV) causes the primary infection manifesting as varicella or chickenpox, with possibility of reactivation later in life. A 71-year-old man presented with headache and lower extremity weakness. There was no evidence of skin lesions to suggest a recent zoster infection. The patient had a history of multiple myeloma diagnosed 2 years earlier, treated with chemotherapy and autologous stem cell transplant. Antimicrobial prophylaxis was discontinued 12 months after the transplant. MRI of the brain demonstrated areas of T2/fluid-attenuated inversion recovery hyperintensity in bilateral cerebral white matter and MRI of the spine demonstrated enhancement along the cauda equine. Cerebrospinal fluid (CSF) analysis showed lymphocytic pleocytosis and VZV DNA was detected by PCR in the CSF. The patient was treated with 8 weeks of antiviral therapy with complete resolution of symptoms. VZV should be considered in patients with haematopoietic stem cell transplantation presenting with similar neurological manifestations even in the absence of dermatological signs.

Complete remission of VZV reactivation treated with valganciclovir in a patient with total lymphocyte depletion and acute kidney injury after allogeneic bone marrow transplantation

Varicella zoster virus (VZV), a threat for hematopoietic stem cell transplantation (HSCT) recipients, is still one of the most common viral pathogens that affect these patients with a reported incidence ranging between 17% and 50% in the post transplantation period. Valganciclovir (V-GCV), a valine ester pro-drug of GCV orally administrable, has recently shown great activity against CMV infections, but there are no reports of its clinical efficacy against VZV. We here report a case history of a patient with positive serologic test for VZV, who underwent allogeneic HSCT and developed an atypical varicella-like illness. First-line therapy with foscarnet had to be discontinued due rapid development of renal impairment (creatinine: 2.60 mg/dL, urea: 130.6 mg/dL) and therefore was switched to V-GCV. The renal impairment and skin lesions of the patient fully recovered after few days of therapy, even though the patient had complete lymphocyte depletion. This is the first case of a patient with chickenpox-like illness treated successfully with V-GCV.

Development of an IFN-γ ELISpot assay to assess varicella-zoster virus-specific cell-mediated immunity following umbilical cord blood transplantation

Varicella zoster virus (VZV) is a significant cause of morbidity and mortality following umbilical cord blood transplantation (UCBT). For this reason, antiherpetic prophylaxis is administrated systematically to pediatric UCBT recipients to prevent complications associated with VZV infection, but there is no strong, evidence based consensus that defines its optimal duration. Because T cell mediated immunity is responsible for the control of VZV infection, assessing the reconstitution of VZV specific T cell responses following UCBT could provide indications as to whether prophylaxis should be maintained or can be discontinued. To this end, a VZV specific gamma interferon (IFN-γ) enzyme-linked immunospot (ELISpot) assay was developed to characterize IFN-γ production by T lymphocytes in response to in vitro stimulation with irradiated live attenuated VZV vaccine. This assay provides a rapid, reproducible and sensitive measurement of VZV specific cell mediated immunity suitable for monitoring the reconstitution of VZV specific immunity in a clinical setting and assessing immune responsiveness to VZV antigens.  

Clinical features and risk factors for developing varicella zoster virus dissemination following hematopoietic stem cell transplantation

BACKGROUND

We retrospectively analyzed 80 instances of varicella zoster virus (VZV) disease in 72 patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT) and examined the clinical differences between localized and disseminated disease. Risk factors for developing VZV dissemination were also evaluated.

RESULTS

Of the 80 instances, 54 instances were localized diseases and 26 were disseminated diseases. Patient characteristics did not differ significantly between the 2 groups, except for the first-line therapy and the duration from symptom onset to treatment. In the disseminated group, intravenous acyclovir was used as the first-line therapy more frequently, and more time elapsed before beginning antiviral therapy compared with the localized group. In multivariate analyses, the duration from symptom onset to treatment was identified as an independent risk factor that significantly affected the development of VZV dissemination. Gender, total body irradiation, and chronic graft-versus-host disease, of which the latter 2 factors were reported as risk factors for the development of VZV disease after HSCT, did not affect the development of VZV dissemination.

CONCLUSION

Our results suggest that VZV infection or reactivation may easily progress to viremia with delayed use of antiviral agents and may result in VZV dissemination in immunocompromised patients.

Prevention of infection in cancer patients

Patients with cancer vary regarding the nature and level of immunocompromise. Both the underlying malignancy and therapy can influence risk of infectious complications. Therefore, decisions about antimicrobial prophylaxis must be guided by a number of factors: (1) the risk of infection; (2) the potential severity of infection and the likelihood of response to therapy; and (3) the safety and efficacy of antimicrobial prophylaxis. The potential for selection for antibiotic-resistant pathogens should also inform decisions about prophylaxis. When assessing clinical trial data on antimicrobial prophylaxis, two major criteria should be considered: the quality of studies supporting prophylaxis (randomized, blinded studies are optimal) and the expected benefit of prophylaxis, measured in terms of prevention of morbidity and potentially mortality. This chapter reviews the epidemiology and clinical trial data on prophylaxis against the major bacterial, viral, and fungal diseases in patients with cancer. Gaps in knowledge and alternative approaches, such as the use of newer diagnostics, are discussed.

Diagnosis and treatment of viral diseases in recipients of allogeneic hematopoietic stem cell transplantation

Viral infections are important causes of morbidity and mortality after allogeneic stem cell hematopoietic transplantation (allo-HSCT). Although most viral infections present with asymptomatic or subclinical manifestations, viruses may result in fatal complications in severe immunocompromised recipients. Reactivation of latent viruses, such as herpesviruses, is frequent during the immunosuppression that occurs with allo-HSCT. Viruses acquired from community, such as the respiratory and gastrointestinal viruses, are also important pathogens of post-transplant viral diseases. Currently, molecular diagnostic methods have replaced or supplemented traditional methods, such as viral culture and antigen detection, in diagnosis of viral infections. The utilization of polymerase chain reaction facilitates the early diagnosis. In view of lacking efficacious agents for treatment of viral diseases, prevention of viral infections is extremely valuable. Application of prophylactic strategies including preemptive therapy reduces viral infections and diseases. Adoptive cellular therapy for restoring virus-specific immunity is a promising method in the treatment of viral diseases.

Live attenuated varicella-zoster vaccine in hematopoietic stem cell transplantation recipients

Hematopoietic stem cell transplantation (HSCT) recipients are at risk for varicella-zoster virus (VZV) reactivation. Vaccination may help restore VZV immunity; however, the available live attenuated VZV vaccine (Zostavax) is contraindicated in immunocompromised hosts. We report our experience with using a single dose of VZV vaccine in 110 adult autologous and allogeneic HSCT recipients who were about 2 years after transplantation, free of graft-versus-host disease, and not receiving immunosuppression. One hundred eight vaccine recipients (98.2%) had no clinically apparent adverse events with a median follow-up period of 9.5 months (interquartile range, 6 to 16; range, 2 to 28). Two vaccine recipients (1.8%) developed a skin rash (one zoster-like rash with associated pain, one varicella-like) within 42 days post-vaccination that resolved with antiviral therapy. We could not confirm if these rashes were due to vaccine (Oka) or wild-type VZV. No other possible cases of VZV reactivation have occurred with about 1178 months of follow-up. Live attenuated zoster vaccine appears generally safe in this population when vaccinated as noted; the overall vaccination risk needs to be weighed against the risk of wild-type VZV disease in this high-risk population.

Incidence and risk factors for herpes zoster following heart transplantation

BACKGROUND

Data on the incidence, timing, and risk factors for herpes zoster (HZ) in heart transplant (HT) recipients are limited.

METHODS

We determined HZ incidence rates and actuarial estimates of time to first HZ episode in 314 HT recipients at our institution from 1995 to 2010. We developed Cox models to assess potential risk factors for HZ in HT.

RESULTS

Median age at HT was 54 (range, 17-71) years; 237 (76%) were male. There were 60 episodes of HZ in 51 patients, with an overall incidence rate of 31.6 cases (95% confidence interval [CI], 23.5-41.6)/1000 person-years. Although most cases occurred during the first post-HT year, cumulative HZ incidence was 0.078 at 1, 0.15 at 5, and 0.20 at 10 years. Many patients had substantial HZ morbidity, including 14% with HZ ophthalmicus and 45% with post-herpetic neuralgia. Adjusting for age, gender, and acute cellular rejection episodes, exposure to mycophenolate mofetil (MMF) was an independent risk factor for HZ (adjusted hazard ratio [HR] 2.18; 95% CI, 1.20-3.96; P = 0.01), while ganciclovir-based cytomegalovirus prophylaxis reduced HZ risk (adjusted HR 0.09; 95% CI, 0.01-0.71; P = 0.02). Although age and female gender increased HZ risk, the magnitude of their effect was not statistically significant in Cox models.

CONCLUSIONS

HZ is common and morbid after HT, particularly with MMF exposure. Ganciclovir prophylaxis is effective in reducing the short-term risk of HZ, but the steady incidence of cases for years post HT makes long-term HZ prevention challenging. Augmenting varicella zoster virus immunity post HT with vaccines warrants further exploration.

Delayed opportunistic infections in hematopoietic stem cell transplantation patients: a surmountable challenge

Changes in the transplantation procedure and the implementation of effective supportive care strategies have decreased the incidence of infectious complications early after conditioning therapy for allogeneic hematopoietic stem cell transplantation (HCT) and have extended the duration of risks later. Therefore, the types of infections that cause significant morbidity and the timing of risks have changed. These late infections are caused by all types of organisms, bacterial, viral, and fungal, but risks are predictable and surmountable with the use of tailored prevention strategies. Specifically, recent studies document prolonged risks for bacterial infections in the setting of GVHD, especially those caused by encapsulated organisms and those secondary to impaired Ab responses. Both prophylaxis and vaccination strategies can be used as a means to prevent infections, which typically manifest in the respiratory tract. Multiple viruses cause infection later after HCT, including several herpesviruses (eg, CMV and varicella zoster virus) and other respiratory viruses such as influenza and adenovirus. These infections can cause severe disease with diagnostic challenges, but prevention strategies using enhanced monitoring and/or prophylaxis may be effective. Finally, fungi also cause disease late after HCT, especially filamentous fungi (eg, Aspergillus species and Mucormycoses) and Pneumocystis jiroveci; prophylactic strategies may be used successfully to prevent invasive infection. Late infections and methods to prevent them are reviewed herein.

Allotype analysis to distinguish the origin of varicella-zoster virus immunoglobulin G after allogeneic stem cell transplantation

Varicella-zoster virus (VZV) reactivation is a frequent complication after allogeneic hematopoietic stem cell transplantation (HSCT). Although previous studies have revealed that cellular immunity is important for suppressing reactivation, the role of humoral immunity against VZV has been poorly evaluated. We analyzed inherited polymorphisms in the immunoglobulin G (IgG) heavy chain constant regions of 50 HSCT recipient-donor pairs to distinguish donor-derived and recipient-derived antibodies. Twelve pairs were informative regarding the origin of IgG, since either the donors (n = 3) or recipients (n = 9) were homozygous null for the IgG1m(f) allotype. In these 9 homozygous-null recipients, allotype-specific IgG against VZV were measured by enzyme-linked immunosorbent assay and compared with measles-IgG. All 9 homozygous-null recipients were monitored for more than 1 year after HSCT, with (n = 4, localized zoster) or without (n = 5) clinical VZV disease. In 3 patients with VZV disease, donor-derived IgG against VZV was elevated between 500 to 700 days after HSCT after the episode of VZV disease. In 1 patient who suffered from VZV disease just before HSCT, donor-derived VZV IgG was elevated within 3 months after HSCT. On the other hand, 2 patients who received reduced-intensity conditioning (RIC) transplantation from an IgG1m(f) null donor maintained recipient-derived IgG against VZV for more than 1 year, whereas it was decreased within 3 months in 1 recipient who received conventional conditioning. In conclusion, the production of anti-VZV IgG by recipient plasma cells persists long after RIC. In patients without symptomatic VZV reactivation, donor-derived anti-VZV IgG did not reach titers comparable to those measured in healthy virus carriers.

Eczema herpeticum with herpetic folliculitis after bone marrow transplant under prophylactic acyclovir: are patients with underlying dermatologic disorders at higher risk?

We present an unreported coexistence: eczema herpeticum (EH) with histopathological findings of herpetic folliculitis (HF) after allogeneic bone marrow transplantation (BMT). A patient with atopic dermatitis (AD) underwent allogeneic BMT for idiopathic acquired aplastic anemia. She had been receiving cyclosporine (150 mg/12 h) and acyclovir (400 mg/12 h) for 6 months. A facial rash was observed, composed of monotonous erythematous, umbilicated papulo-vesicles and papulo-crusts <4 mm in size. The histopathological study showed herpetic cytopathic changes within the epidermis that extended into the hair follicle epithelium. Interestingly, microscopic HF has not previously been associated with post-transplant patients or EH. However, it is reasonable to hypothesize that the coexistence of these herpes simplex virus-related events may be underreported in the literature. Although further studies are necessary, we suggest that the prophylactic antiviral dose after BMT be enhanced in patients with underlying dermatologic diseases, especially in those with AD.

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

Varicella zoster virus (VZV) and the two herpes simplex viruses (HSV) are human α-herpesviruses that establish life-long latency in neural ganglia after initial primary infection. In the solid organ transplant (SOT) population, manifestations of VZV or HSV may be seen in up to 70% of recipients if no prophylaxis is used, some of them life and organ threatening. While there are effective vaccines to prevent VZV primary infection and reactivation in immunocompetent adults, these vaccines are contraindicated after SOT because they are live-virus vaccines. For HSV, prevention has focused primarily on antiviral strategies because the immunologic correlates of protection and control are different from VZV, making vaccine development more challenging. Current antiviral therapy remains effective for the majority of clinical VZV and HSV infections.

Varicella-zoster virus-associated fulminant hepatitis following allogeneic hematopoietic stem cell transplantation for multiple myeloma

Disseminated visceral varicella-zoster virus (VZV) infection rarely occurs in recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT). To date, only a few cases of isolated VZV-induced fulminant hepatitis following allo-HSCT have been reported. We herein describe the case of a 47-year-old Japanese man with multiple myeloma who developed fulminant hepatitis 17 months after undergoing allo-HSCT. Despite receiving fresh frozen plasma and platelet transfusions, he developed a bleeding tendency (systemic purpura, petechiae and oral bleeding), slipped into a coma and eventually died. He was retrospectively diagnosed with viscerally disseminated VZV infection based on a postmortem examination and multiplex polymerase chain reaction (PCR) amplification.