Management of HSV, VZV and EBV infections in patients with hematological malignancies and after SCT: guidelines from the Second European Conference on Infections in Leukemia

Interventions to reduce the risk of side-effects of cancer treatments in childhood

INTRODUCTION

Childhood cancers as a group affect around 1 in 500 children but each individual diagnosis is a rare disease. While research largely focuses on improving cure rates, the management of side effects of treatment are high priority for clinicians, families and children and young people.

AREAS COVERED

The prevention and efficient management of infectious complications, oral mucositis, nausea and vomiting and graft-vs-host disease illustrated with examples of implementation research, translation of engineering to care, advances in statistical methodologies, and traditional bench-to-patient development. The reviews draw from existing systematic reviews and well conducted clinical practice guidelines.

EXPERT OPINION

The four areas are driven from patient and family priorities. Some of the problems outlined are ready for proven interventions, others require us to develop new technologies. Advancement needs us to make the best use of new methods of applied health research and clinical trial methodologies. Some of the greatest challenges may be those we're not fully aware of, as new therapies move from their use in adult oncological practice into children. This will need us to continue our collaborative, multi-professional, multi-disciplinary and eclectic approach.

Virucidal effect of mouthwash on acyclovir-resistant herpes simplex virus

OBJECTIVES

The symptoms of herpes simplex viruses type 1 (HSV-1) infections might be severe and persistent in immunocompromised patients in whom they reactivate at a high frequency. The development of Acyclovir (ACV) resistant strains due to long-term treatment with antiviral agents in those patients is not uncommon. The aim of the present study was to assess the virucidal effect of commercially available mouthwashes against ACV-resistant HSV-1 strains.

MATERIALS AND METHODS

Two acyclovir-resistant HSV-1 strains were exposed for 30 s to essential oil-based (Listerine Fresh Burst® and Listerine Zero®), chlorhexidine gluconate 0.2% (Hexidyl®) and povidone-iodine 7.5% (Betadine Gargle®) mouthwashes. Loss of virus infectivity was determined by means of plaque reduction assays in a cell culture system.

RESULTS

All 4 of the tested solutions significantly reduced virus infectivity, with the essential oil-based and povidone-iodine mouthwashes being slightly more efficacious, compared to chlorhexidine.

CONCLUSION

The findings of this analysis revealed that the tested oral rinses demonstrated in-vitro antiviral activity against ACV-resistant HSV. Comparative clinical trials are required to establish the clinical effectiveness of daily use of oral rinses in reducing the appearance of oral HSV lesions in immunocompromised patients.

CD56bright NK cell expansion correlated with EBV reactivation control post allogeneic hematopoietic stem cell transplantation

Natural killer (NK) cells are equipped with anti-Epstein-Barr virus (EBV) function, however, whether EBV infection will affect NK cells reconstitution after allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains unclear. To identify the characteristics of NK cells, we prospectively enrolled 11 patients who occurred EBV reactivation post allo-HSCT and 11 patients without EBV infection as control. We found that that EBV infection induced the expansion of CD56bright and NKG2A+KIR- NK subsets,and decreased the cytotoxicity function of NK cells. The frequency of NKG2A+KIR- NK cells were higher in patients who progressed into post-transplant lymphoproliferative disorder (PTLD) than EBV viremia patients, which also correlated with decreased proliferation and cytotoxic function. By screening the activation receptors of NK cells, we found the DNAM-1+CD56bright NK cells is significantly increased after EBV stimulation, further we demonstrated that DNAM-1 is essential for EBV induced NK cells activation as the cytokine release against EBV-transformed lymphoblastoid cell lines(EBV-LCLs) of CD56bright NK cells were significantly decreased after DNAM-1 blockade. NK cells infusion suppressed the progression of EBV-related tumor mice model. A prospective cohort indicated that old donor age was an independent risk factor for EBV infection. Rapid CD56bri expansion and high expression of DNAM-1 on CD56bri NK cells in response to EBV reactivation correlated with rapid EBV clearance post allo-HSCT in patients with younger donors. In summary, our data showed that high expression of DNAM-1 receptors on NK cell may participate protective CD56bri NK cells response to EBV infection after allo-HSCT.

EBV Reactivation and Disease in Allogeneic Hematopoietic Stem Cell Transplant (HSCT) Recipients and Its Impact on HSCT Outcomes

The acquisition or reactivation of Epstein-Barr virus (EBV) after allogeneic Hematopoietic Stem Cell Transplant (HSCT) can be associated with complications including the development of post-transplant lymphoproliferative disorder (PTLD), which is associated with significant morbidity and mortality. A number of risk factors for PTLD have been defined, including T-cell depletion, and approaches to monitoring EBV, especially in high-risk patients, with the use of preemptive therapy upon viral activation have been described. Newer therapies for the preemption or treatment of PTLD, such as EBV-specific cytotoxic T-cells, hold promise. Further studies to help define risks, diagnosis, and treatment of EBV-related complications are needed in this at-risk population.

Varicella-Zoster Virus Reactivation After Pediatric Allogeneic Hematopoietic Stem Cell Transplantation, Single-Center Experience of Acyclovir Prophylaxis

BACKGROUND

Varicella-zoster virus (VZV) reactivation is the most common infectious complication in the late posthematopoietic stem cell transplantation (HSCT) period and is reported as 16%-41%. Acyclovir prophylaxis is recommended for at least 1 year after HSCT to prevent VZV infections. However, studies on the most appropriate prophylaxis are ongoing in pediatric patients.

METHODS

Patients who underwent allogeneic HSCT between January 1, 1996 and January 1, 2020 were retrospectively analyzed to outline the characteristics of VZV reactivation after allogeneic HSCT in pediatric patients using 6 months acyclovir prophylaxis.

RESULTS

There were 260 patients and 273 HSCTs. Median age was 10.43 (0.47-18.38), and 56% was male. Median follow-up was 2325 days (18-7579 days). VZV reactivation occurred in 21.2% (n = 58) at a median of 354 (55-3433) days post-HSCT. The peak incidence was 6-12 months post-HSCT (43.1%). Older age at HSCT, female gender, history of varicella infection, lack of varicella vaccination, low lymphocyte, CD4 count, and CD4/CD8 ratio at 9 and 12 months post-HSCT was found as a significant risk for herpes zoster (HZ) in univariate analysis, whereas history of varicella infection and low CD4/CD8 ratio at 12 months post-HSCT was an independent risk factor in multivariate analysis.

CONCLUSIONS

Tailoring acyclovir prophylaxis according to pre-HCT varicella history, posttransplant CD4 T lymphocyte counts and functions, and ongoing immunosuppression may help to reduce HZ-related morbidity and mortality.

Impact of prophylaxis with rituximab on EBV-related complications after allogeneic hematopoietic cell transplantation in children

Background

Children undergoing allo-HCT are at high risk of EBV-related complications. The objective of the study was to analyze the impact of prophylactic post-transplant rituximab on EBV infection and EBV-PTLD in children after allo-HCT, to determine the risk factors for the development of EBV infection and EBV-PTLD and to determine their outcomes. Additionally, the impact of EBV-driven complications on transplant outcomes was analyzed.

Methods

Single center retrospective analysis of EBV-related complications in pediatric population undergoing allo-HCT, based on strategy of prophylaxis with rituximab. Overall 276 consecutive children, including 122 on prophylaxis, were analyzed for EBV-driven complications and transplant outcomes.

Results

Prophylaxis with rituximab resulted in significant reduction of EBV infection (from 35.1% to 20.5%; HR=2.7; p<0.0001), and EBV-PTLD (from 13.0% to 3.3%; HR=0.23; p=0.0045). A trend for improved survival was also observed (HR=0.66; p=0.068), while non-relapse mortality was comparable in both cohorts. The peak value of viral load was a risk factor in the development of EBV-PTLD: 10-fold higher peak viral load in comparison to the baseline 104 copies/mL, caused a 3-fold (HR=3.36; p<0.001) increase in the risk of EBV-PTLD. Rituximab treatment was effective as a preemptive therapy in 91.1%, and in 70.9% in EBV-PTLD. Patients who developed PTLD had dismal 5-year overall survival (29% vs 60%; p<0.001), and an increased risk of relapse (72% vs 35%; p=0.024).

Conclusions

Rituximab for prophylaxis of EBV infection and EBV-PTLD was highly effective in pediatric population. Treatment of EBV-PTLD was successful in 70%, however the occurrence of EBV-PTLD was associated with an increased risk of relapse of primary malignant disease.

Advances and prospect in herpesviruses infections after haematopoietic cell transplantation: closer to the finish line?

BACKGROUND

Herpesviruses represent common and significant infectious complications after allogeneic haematopoietic cell transplantation (HCT). In the last decade, major advances in the prevention and treatment of these infections were accomplished.

OBJECTIVES

The aim of this paper is to review the recent advances in the prophylaxis and treatment of herpesvirus infections after allogeneic HCT, to assess the persisting challenges, and to offer future directions for the prevention and management of these infections.

SOURCES

We searched PubMed for relevant literature regarding specific herpesviruses complicating allogeneic HCT through March 2024.

CONTENT

The largest advances in this past decade were witnessed for cytomegalovirus (CMV) with the advent of letermovir for primary prophylaxis and the development of maribavir as an option for refractory and/or resistant CMV infections in transplant recipients. For varicella zoster virus, prevention of reactivation with the recombinant zoster vaccine offers an additional prophylactic intervention. Pritelivir is being explored for the treatment of drug-resistant or refractory Herpes simplex virus infections. Although rituximab is now an established option for preemptive therapy for Epstein-Barr virus, Human Herpesvirus-6 remains the most elusive virus of the herpesvirus family, with a lack of evidence supporting the benefit of any agent for prophylaxis or for optimal preemptive therapy.

IMPLICATIONS

Although considerable advances have been achieved for the treatment and prevention of herpes virus infections, most notably with CMV, the coming years should hold additional opportunities to tame the beast in these herpesviruses postallogeneic HCT, with the advent of new antivirals, cell-mediated immunity testing, and cytotoxic T lymphocytes infusions.

Antiviral cellular therapy for enhancing T-cell reconstitution before or after hematopoietic stem cell transplantation (ACES): a two-arm, open label phase II interventional trial of pediatric patients with risk factor assessment

Viral infections remain a major risk in immunocompromised pediatric patients, and virus-specific T cell (VST) therapy has been successful for treatment of refractory viral infections in prior studies. We performed a phase II multicenter study (NCT03475212) for the treatment of pediatric patients with inborn errors of immunity and/or post allogeneic hematopoietic stem cell transplant with refractory viral infections using partially-HLA matched VSTs targeting cytomegalovirus, Epstein-Barr virus, or adenovirus. Primary endpoints were feasibility, safety, and clinical responses (>1 log reduction in viremia at 28 days). Secondary endpoints were reconstitution of antiviral immunity and persistence of the infused VSTs. Suitable VST products were identified for 75 of 77 clinical queries. Clinical responses were achieved in 29 of 47 (62%) of patients post-HSCT including 73% of patients evaluable at 1-month post-infusion, meeting the primary efficacy endpoint (>52%). Secondary graft rejection occurred in one child following VST infusion as described in a companion article. Corticosteroids, graft-versus-host disease, transplant-associated thrombotic microangiopathy, and eculizumab treatment correlated with poor response, while uptrending absolute lymphocyte and CD8 T cell counts correlated with good response. This study highlights key clinical factors that impact response to VSTs and demonstrates the feasibility and efficacy of this therapy in pediatric HSCT.

Management of oral herpes simplex virus infections: The problem of resistance. A narrative review

Herpes Simplex Virus (HSV) type 1 (HSV-1) and type 2 (HSV-2) are among the most common human viral pathogens, affecting several billion people worldwide. Although in healthy patients clinical signs and symptoms of HSV infection are usually mild and self-limiting, HSV-infections in immunocompromised patients are frequently more aggressive, persistent, and even life-threatening. Acyclovir and its derivatives are the gold standard antiviral drugs for the prevention and treatment of HSV infections. Although the development of acyclovir resistance is a rather uncommon condition, it may be associated with serious complications, especially in immunocompromised patients. In this review, we aim to address the problem of drug resistant HSV infection and discuss the available alternative therapeutic interventions. All relative studies concerning alternative treatment modalities of acyclovir resistant HSV infection published in PubMed between 1989 to 2022 were reviewed. Long-term treatment and prophylaxis with antiviral agents predisposes to drug resistance, especially in immunocompromised patients. Cidofovir and foscarnet could serve as alternative treatments in these cases. Although rare, acyclovir resistance may be associated with severe complications. Hopefully, in the future, novel antiviral drugs and vaccines will be available in order to avoid the existing drug resistance.

Dual T cell depletion for graft versus host disease prevention in peripheral blood haploidentical hematopoietic cell transplantation for adults with hematological malignancies

The ideal immunosuppressive agents to complement post-transplant cyclophosphamide (PTCy) in PBSC-based haploidentical hematopoietic cell transplantation (haplo-HCT) remain debated. This study looks at our experience with ATG-PTCy-Cyclosporine (CsA) prophylaxis in PB haplo-HCT since 2015. Between October 2015 and December 2021, 157 adults underwent haploidentical hematopoietic cell transplantation (haplo-HCT) using a GVHD prophylaxis regimen comprising rabbit-ATG, PTCy, and CsA. Among these patients, 76.4% received a total ATG dose of 4.5 mg/kg, and 23.5% received 2 mg/kg. T-cell replete peripheral blood stem cell (PBSC) grafts were infused on day 0. The study reported a median follow-up of 32 months (range 0.3-61.64) for survivors. The cumulative incidence of grade II-IV and grade III-IV acute GVHD at day +100 was 26.3% and 9.5%, respectively. Moderate/severe chronic GVHD at 1 year was 19.9%. The 2-year overall survival (OS) was 49.4%, with a relapse-free survival (RFS) of 44.6%. In multivariate analysis, older patients, and those with high/very-high disease risk indices (DRI) were at higher risk for worse OS and higher non-relapse mortality (NRM). The study confirms that using PTCy and ATG (4.5 mg/kg), alongside CsA is safe and effective in preventing GVHD when using peripheral blood as the stem cell source in haploidentical hematopoietic cell transplantation (haplo-HCT).

Clinical description and outcome of overall varicella-zoster virus-related organ dysfunctions admitted in intensive care units: the VAZOREA cohort study

BACKGROUND

Due to aging population and increasing part of immunocompromised patients, a raise in life-threatening organ damage related to VZV can be expected. Two retrospective studies were already conducted on VZV in ICU but focused on specific organ injury. Patients with high-risk of VZV disease still must be identified. The objective of this study was to report the clinical features and outcome of all life-threatening VZV manifestations requiring intensive care unit (ICU) admission. This retrospective cohort study was conducted in 26 French ICUs and included all adult patients with any life-threatening VZV-related event requiring ICU admission or occurring in ICU between 2010 and 2019.

RESULTS

One-hundred nineteen patients were included with a median SOFA score of 6. One hundred eight patients (90.8%) were admitted in ICU for VZV disease, leaving 11 (9.2%) with VZV disease occurring in ICU. Sixty-one patients (51.3%) were immunocompromised. Encephalitis was the most prominent organ involvement (55.5%), followed by pneumonia (44.5%) and hepatitis (9.2%). Fifty-four patients (45.4%) received norepinephrine, 72 (60.5% of the total cohort) needed invasive mechanical ventilation, and 31 (26.3%) received renal-replacement therapy. In-hospital mortality was 36.1% and was significantly associated with three independent risk factors by multivariable logistic regression: immunosuppression, VZV disease occurring in ICU and alcohol abuse. Hierarchical clustering on principal components revealed five phenotypically distinct clusters of patients: VZV-related pneumonia, mild encephalitis, severe encephalitis in solid organ transplant recipients, encephalitis in other immunocompromised hosts and VZV disease occurring in ICU. In-hospital mortality was highly different across phenotypes, ranging from zero to 75% (p < 0.001).

CONCLUSION

Overall, severe VZV manifestations are associated with high mortality in the ICU, which appears to be driven by immunosuppression status rather than any specific organ involvement. Deciphering the clinical phenotypes may help clinicians identify high-risk patients and assess prognosis.

Prevalence, management, and new treatment modalities of EBV-DNA-emia and EBV-PTLD after allo-HCT: survey of Infectious Diseases Working Party EBMT

The aim of this study was to determine the current approach of EBV-driven post-transplant complications in context of monitoring, diagnosis, prevalence and treatment in EBMT transplant centers. Routine serology testing in patient and donor before HCT is performed in 95.5% centers. Pretransplant EBV-DNA is routinely tested in all patients in 32.7% centers. Monitoring for EBV infection is feasible in 98.2% centers: including 66.7% centers using standardized PCR. Post-HCT regular monitoring is performed in all patients in 80.5% centers. Anti-EBV prophylaxis with rituximab is used in 12.4% centers. Frequency of csEBV-DNA-emia was 7.4% (adults: 6.2%, children: 12.6%). The PCR threshold used to start preemptive treatment was differentiated among centers. Frequency of EBV-PTLD was 1.6% (adults: 1.3%; children: 3.5%). First-line therapy of EBV-driven complications was rituximab and reduction of immunosuppressive therapy. The rate of failure of first-line preemptive treatment was 12.0%. EBV-specific viral-specific T-lymphocytes were available in 46.0% centers. A number of new experimental therapies were given in 28 patients with resistant/refractory PTLD. In conclusion, the prevalence of EBV-DNA-emia and EBV-PTLD over the period 2020-2021 decreased in comparison to historical data. New trends (routine pretransplant screening for EBV-DNA, wider access to VST, new experimental therapies) are being observed in management of EBV infection after allo-HCT.

Rituximab for posttransplant lymphoproliferative disorder - therapeutic, preemptive, or prophylactic?

To minimize mortality due to posttransplant lymphoproliferative disorder (PTLD), the following strategies have been used: (1) Therapy without EBV Monitoring, i.e., administration of rituximab after PTLD diagnosis, usually by biopsy, in the absence of routine Epstein-Barr virus (EBV) DNAemia monitoring, (2) Prompt Therapy, i.e., monitoring EBV DNAemia, searching for PTLD by imaging when the DNAemia has exceeded a pre-specified threshold, and administration of rituximab if the imaging is consistent with PTLD, (3) Preemptive Therapy, i.e., monitoring EBV DNAemia and administration of rituximab when the DNAemia has exceeded a pre-specified threshold, and (4) Prophylaxis, i.e., administration of rituximab to all transplant recipients. The superiority of one of these strategies over the other strategies has not been established. Here we review the pros and cons of each strategy. Preemptive therapy or prophylaxis may currently be preferred for patients who are at a high risk of dying due to PTLD. However, Therapy without EBV Monitoring may be used for both high- and low-risk patients in the future, if effective and relatively non-toxic therapies for rituximab-refractory PTLD (e.g., EBV-specific T cells) have become easily available.

Vaccine schedule recommendations and updates for patients with hematologic malignancy post-hematopoietic cell transplant or CAR T-cell therapy

Revaccination after receipt of a hematopoietic cell transplant (HCT) or cellular therapies is a pillar of patient supportive care, with the potential to reduce morbidity and mortality linked to vaccine-preventable infections. This review synthesizes national, international, and expert consensus vaccination schedules post-HCT and presents evidence regarding the efficacy of newer vaccine formulations for pneumococcus, recombinant zoster vaccine, and coronavirus disease 2019 in patients with hematological malignancy. Revaccination post-cellular therapies are less well defined. This review highlights important considerations around poor vaccine response, seroprevalence preservation after cellular therapies, and the optimal timing of revaccination. Future research should assess the immunogenicity and real-world effectiveness of new vaccine formulations and/or vaccine schedules in patients post-HCT and cellular therapy, including analysis of vaccine response that relates to the target of cellular therapies.

Hematopoietic stem cell transplantation and the noncytomegalovirus herpesviruses

Although hematopoietic stem cell transplantation (HSCT) and other cellular therapies have significantly improved outcomes in the management of multiple hematological and nonhematological malignancies, the resulting impairment in humoral and cellular response increases the risk for opportunistic infection as an undesirable side effect. With their ability to establish latent infection and reactivate when the host immune system is at its weakest point, the Herpesviridae family constitutes a significant proportion of these opportunistic pathogens. Despite recent advancements in preventing and managing herpesvirus infections, they continue to be a common cause of significant morbidity and mortality in transplanted patients. Herein, we aim to provide and update on herpesvirus other than cytomegalovirus (CMV) affecting recipients of HSCT and other cellular therapies.

[Clinical significance of Epstein-Barr Virus detection in the cerebrospinal fluid of patients who underwent hematopoietic stem cell transplantation]

Objective: To analyze the detection rate, clinical significance, and prognosis of Epstein-Barr virus (EBV) in the cerebrospinal fluid (CSF) of patients following allogeneic hematopoietic stem cell transplantation. Methods: A retrospective analysis was performed on 1100 patients who underwent the CSF virus test after allogeneic hematopoietic stem cell transplantation in Peking University People's Hospital between January 2017 and June 2022. Among them, 19 patients were screened positive for EBV in their CSF, and their clinical characteristics, treatment, and prognosis were analyzed. Results: Among 19 patients with EBV-positive cerebrospinal fluid, 12 were male and 7 were female, with 5 patients aged <18 years and 12 aged ≥18 years, with a median age of 27 (5-58) years old. There were 7 cases of acute myeloid leukemia, 8 of acute lymphocytic leukemia, 2 of aplastic anemia, 1 of Hodgkin's lymphoma, and 1 of hemophagocytic syndrome. All 19 patients underwent haploid hematopoietic stem cell transplantation, including 1 secondary transplant. Nineteen patients had neurological symptoms (headache, dizziness, convulsions, or seizures), of which 13 had fever. Ten cases showed no abnormalities in cranial imaging examination. Among the 19 patients, 6 were diagnosed with EB virus-related central nervous system diseases, with a median diagnosis time of 50 (22-363) days after transplantation. In 9 (47.3%) patients, EBV was detected in their peripheral blood, and they were treated with intravenous infusion of rituximab (including two patients who underwent lumbar puncture and intrathecal injection of rituximab). After treatment, EBV was not detected in seven patients. Among the 19 patients, 2 died from EBV infection and 2 from other causes. Conclusion: In patients who exhibited central nervous system symptoms after allogeneic hematopoietic stem cell transplantation, EBV should be screened as a potential pathogen. EBV detected in the CSF may indicate an infection; however, it does not confirm the diagnosis.

Aplastic Anemia with Epstein-Barr Virus Reactivation after Anti-thymocyte Globulin Therapy

Lymphoproliferative disorders and Epstein-Barr virus reactivation (EBV-LPDs) have various forms of onset, ranging from infectious mononucleosis-like syndrome (IM-like) to lymphoma, although whether or not IM-like progresses to lymphoma remains unclear. A 61-year-old man was diagnosed with aplastic anemia (AA). Polyclonal atypical B-lymphocytes were observed in the peripheral blood, and IM-like was diagnosed. Atypical lymphocytes disappeared, but a gastrointestinal examination revealed diffuse large B-cell lymphoma (DLBCL). Rituximab was initiated but later discontinued because of severe acute respiratory syndrome coronavirus 2 infection. Pancytopenia due to AA exacerbation recurred. The patient ultimately died of multiple organ failure due to bacterial infection.

Varicella vaccine meningoencephalitis in a child receiving autologous bone marrow transplantation

BACKGROUND

Varicella vaccine, a live-attenuated Oka-strain of varicella zoster virus (VZV), is a recommended childhood vaccine by many countries. As with wild varicella strain, after primary infection, the live-attenuated virus can establish latency in sensory ganglia and reactivate causing vaccine-strain illnesses: herpes zoster (HZ), visceral or peripheral and central nervous system dissemination. We report a case of early reactivation of live-attenuated virus-HZ and meningoencephalitis-in an immunocompromised child.

METHODS

This is a retrospective descriptive report of a case, in a tertiary pediatric hospital, CHU Sainte-Justine (Montréal, Canada).

RESULTS

An 18 month-year old girl diagnosed with a primitive neuro-ectodermal tumor (PNET) received the day prior to diagnosis, a first varicella vaccine (MMRV). She received chemotherapy 20 days post MMRV vaccine and autologous bone marrow transplantation 3 months post vaccination. She was considered not eligible, to acyclovir prophylaxis prior transplantation (positive for VZV IgG and negative for herpes simplex virus IgG by ELISA). At day 1 post transplantation, she developed dermatomal HZ and meningoencephalitis. Oka-strain varicella was isolated, she was treated with acyclovir and foscarnet. Neurologic status improved in 5 days. Control of VZV viral load in cerebrospinal fluid showed a slow decrease to from 5.24 log 10 copies/mL to 2.14 log 10 copies/mL in 6 weeks. No relapse was observed. She recovered without neurological sequelae.

CONCLUSIONS

Our experience highlights the importance of conducting a thorough medical history regarding vaccination and serological status of newly immunocompromised patients. Intensive chemotherapy succeeding live vaccine administration <4 weeks could have influenced early and severe viral reactivation. Early initiation of prophylactic antiviral treatment is questioned in such circumstances.

18F-FDG PET/CT findings in a patient with blastic plasmacytoid dendritic cell neoplasm and post-transplant lymphoproliferative disorder after hematopoietic stem cell transplantation: a case report

Background

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an extremely rare hematopoietic malignancy, which originating from precursors of plasmacytoid dendritic cells. Allogeneic hematopoietic stem cell transplantation (HSCT) is normally considered in the treatment of BPDCN patients to acquire sustained remission. Post-transplant lymphoproliferative disorder (PTLD) is a group of conditions involving abnormal lymphoid cells proliferation in the context of extrinsic immunosuppression after solid organ transplantation (SOT) or HSCT. Herein, we report a patient with BPDCN, who suffered from PTLD after allogeneic HSCT.

Case presentation

A 66-year-old man was diagnosed with BPDCN, confirmed by pathologic examination after splenectomy. The post-surgery 18F-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (18F-FDG PET/CT) showed multifocal 18F-FDG avidity in the left cheek, lymph nodes and bone marrow. The patient started chemotherapy, followed by allogeneic HSCT and immunosuppressive therapy. Four months after the HSCT, the patient developed intermittent fever and recurrent lymphadenopathy, accompanied with progressively elevated Epstein-Barr virus (EBV)-DNA both in serum and lymphocytes. 18F-FDG PET/CT was performed again and found multiple new enlarged 18F-FDG-avid lymph nodes, while the previous hypermetabolic lesions all disappeared. The pathology of mesenteric lymph node indicated a monomorphic PTLD (diffuse large B-cell lymphoma). Then the immunosuppressive medications were stopped and two cycles of Rituximab were given, and the follow-up CT scan indicated a complete response.

Conclusion

When patients with BPDCN recurred new enlarged lymph nodes after allogeneic HSCT and immunosuppressive therapy, PTLD should be taken into consideration. 18F-FDG PET/CT may provide additional evidence for supporting or refuting the suspicion of PTLD, and suggest lesions accessible for biopsy.

Dermatologic complications in transplantation and cellular therapy for acute leukemia

Adoptive cellular immunotherapy, mainly hematopoietic stem cell transplant and CAR-T cell therapy have revolutionized treatment of patients with acute leukemia. Indications and inclusion criteria for these treatments have expanded in recent years. While these therapies are associated with significant improvements in disease response and overall survival, patients may experience adverse events from associated chemotherapy conditioning, engraftment, cytokine storm, supportive medications, and post-transplant maintenance targeted therapies. Supportive oncodermatology is a growing specialty to manage cutaneous toxicities resulting from the anti-cancer therapies. In this review, we summarize diagnosis and management of the common cutaneous adverse events including drug eruptions, graft-versus-host disease, neoplastic and paraneoplastic complications in patients undergoing cellular therapies.

Nondrug Intervention for Opportunistic Infections in Individuals With Hematological Malignancy: Systematic Review

BACKGROUND

Hematological malignancies disturb the blood, lymph nodes, and bone marrow. Taking medications for treating opportunistic infections (OIs) in these individuals may enhance the risk of medication interaction as well as adverse drug reactions.

OBJECTIVE

This review aims to evaluate the effectiveness of nondrug interventions in reducing OIs among patients with hematological cancers.

METHODS

The PubMed, CENTRAL (Cochrane Central Register of Controlled Trials), and Embase databases were searched on December 26, 2022, for all randomized controlled trials (RCTs). The primary endpoint was OIs. The quality of included studies was assessed by the Cochrane Risk-of-Bias tool.

RESULTS

A total of 6 studies were included in this review with 4 interventions: (1) types of mouthwash received, (2) presence of coating on central venous catheters (CVCs), (3) use of well-fitted masks, and (4) types of diet consumed. The results were presented in 8 different comparisons: (1) chlorhexidine-nystatin versus saline mouth rinse, (2) chlorhexidine versus saline mouth rinse, (3) nystatin versus saline mouth rinse, (4) chlorhexidine silver sulfadiazine-coated CVCs versus uncoated catheters, (5) well-fitted masks versus no mask, (6) amine fluoride-stannous fluoride versus sodium fluoride mouthwash, (7) low-bacterial diet versus standard hospital diet, and (8) herbal versus placebo mouthwash. No clear differences were reported in any of the outcomes examined in the first 3 comparisons. There were also no clear differences in the rate of catheter-related bloodstream infection or insertion site infection between the use of chlorhexidine silver sulfadiazine-coated CVCs versus uncoated catheters in the patients. Further, no significant differences were seen between patients who used a well-fitted mask and those without a mask in the incidence of OI. The all-cause mortality and mortality due to OI were similar between the 2 groups. There was no clear difference in all-cause mortality, although common adverse effects were reported in patients who used sodium fluoride mouthwash compared with those using amine fluoride-stannous fluoride mouthwash. There was no evidence of any difference in the incidence of possible invasive aspergillosis or candidemia between patients who consumed a low-bacterial diet and a standard diet. For the last comparison, no significant difference was seen between patients who received herbal and placebo mouthwash.

CONCLUSIONS

Very limited evidence was available to measure the effectiveness of nondrug interventions in hematological cancers. The effectiveness of the interventions included in this review needs to be evaluated further in high-quality RCTs in a dedicated setting among patients with hematological malignancies.

TRIAL REGISTRATION

PROSPERO International Prospective Register of Systematic Reviews CRD42020169186; https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=169186.

Who is the patient at risk for EBV reactivation and disease: expert opinion focused on post-transplant lymphoproliferative disorders following hematopoietic stem cell transplantation

INTRODUCTION

Post-transplant lymphoproliferative disorders (PTLD) represent a diverse group of diseases. They develop as a consequence of uncontrolled proliferation of lymphoid or plasmacytic cells resulting from T-cell immunosuppression after transplantation of either hematopoietic cells (HCT) or solid organs (SOT), caused mainly by latent Epstein-Barr virus (EBV). The risk for EBV recurrence is dependent on the level of incompetency of the immune system, presented as an impairment of T-cell immunity.

AREAS COVERED

This review summarizes the data on incidence and risk factors of EBV infection in patients after HCT. The median rate of EBV infection in HCT recipients was estimated at 30% after allogeneic and<1% after autologous transplant; 5% in non-transplant hematological malignancies; 30% in SOT recipients. The median rate of PTLD after HCT is estimated at 3%. The most frequently reported risk factors for EBV infection and disease include: donor EBV-seropositivity, use of T-cell depletion, especially with ATG; reduced-intensity conditioning; mismatched family or unrelated donor transplants; and acute or chronic graft-versus-host-disease.

EXPERT OPINION

The major risk factors for EBV infection and EBV-PTLD can be easily identified: EBV-seropositive donor, depletion of T-cells, and the use of immunosuppressive therapy. Strategies for avoiding risk factors include elimination EBV from the graft and improving T-cell function.

Kronisk transplantat-mot-vert-sykdom

Chronic graft-versus-host disease is a late complication of allogeneic stem cell transplantation and leads to chronic inflammation and fibrosis in various organs due to dysregulation of donor immune cells. The disease can occur in all organs, but is most frequently seen in the skin, eyes, oral cavity, gastrointestinal tract, genitalia, lungs, muscles, fascia and joints. Chronic graft-versus-host disease is associated with considerable morbidity and mortality, and treatment requires close collaboration between different parts of the specialist health services. This article provides a clinical review of chronic graft-versus-host disease based on a non-systematic literature search and the authors' own clinical experience.

Distinct Immune Reconstitution Profiles Captured by Immune Functional Assays at 6 Months Post Allogeneic Hematopoietic Stem Cell Transplantation

Immune reconstitution after allogeneic-hematopoietic-stem-cell transplantation (allo-HSCT) is a complex and individual process. In this cross-sectional study, whole-blood (WB) immune functional assay (IFA) was used to characterize immune function by assessing immune-related gene/pathway alterations. The usefulness of this tool in the context of infection, 6 months after transplantation, was evaluated. Sixty allo-HSCT recipients at 6 months after transplantation and 10 healthy volunteers (HV) were included. WB was stimulated in standardized TruCulture tubes using lipopolysaccharides and Staphylococcal enterotoxin B. Gene expression was quantified using a custom 144-gene panel using NanoString nCounter technology and analyzed using Ingenuity Pathway Analysis. The relationships between immune function and clinical characteristics, immune cell counts, and post-transplantation infections were assessed. Allo-HSCT recipients were able to activate similar networks of the innate and adaptive immune response compared to HV, with, nevertheless, a lower intensity. A reduced number and a lower expression of genes associated with immunoregulatory and inflammatory processes were observed in allo-HSCT recipients. The use of immunosuppressive treatments was associated with a protracted immune reconstitution revealed by transcriptomic immunoprofiling. No difference in immune cell counts was observed among patients receiving or not receiving immunosuppressive treatments using a large immunophenotyping panel. Moreover, the expression of a set of genes, including CCL3/CCL4, was significantly lower in patients with Herpesviridae reactivation (32%, 19/60), which once again was not identified using classical immune cell counts. Transcriptional IFA revealed the heterogeneity among allo-HSCT recipients with a reduced immune function, a result that could not be captured by circulating immune cell counts. This highlights the potential added value of this tool for the personalized care of immunocompromised patients.

Diagnostic Value of Whole-Blood and Plasma Samples in Epstein-Barr Virus Infections

Epstein-Barr virus (EBV) is an oncogenic virus classified by the World Health Organization as a class 1 carcinogen. Post-transplant lymphoproliferative disorders are believed to be strongly related to an EBV infection. Monitoring of EBV DNAemia is recommended to assess the risk of reactivation of latent infection and to assess the effectiveness of therapy. Currently, various types of clinical specimens are used for this purpose. The aim of the study was to assess a reliable method of EBV viral load investigation depending on the clinical material used: whole blood or plasma samples. We found that of 134 EBV-DNA-positive whole-blood samples derived from 51 patients (mostly hemato-oncology or post-transplantation), only 43 (32.1%) were plasma-positive. Of these, 37 (86.0%) had lower plasma DNAemia compared to the corresponding whole-blood samples. We conclude that whole-blood samples have a higher sensitivity than plasma samples in EBV DNA detection. The clinical utility of the tests is unclear, but our results suggest that either whole blood or plasma should be used consistently for EBV viral load monitoring.

Post-Transplant Lymphoproliferative Disease (PTLD) after Allogeneic Hematopoietic Stem Cell Transplantation: Biology and Treatment Options

Post-transplant lymphoproliferative disease (PTLD) is a serious complication occurring as a consequence of immunosuppression in the setting of allogeneic hematopoietic stem cell transplantation (alloHSCT) or solid organ transplantation (SOT). The majority of PTLD arises from B-cells, and Epstein-Barr virus (EBV) infection is present in 60-80% of the cases, revealing the central role played by the latent infection in the pathogenesis of the disease. Therefore, EBV serological status is considered the most important risk factor associated with PTLDs, together with the depth of T-cell immunosuppression pre- and post-transplant. However, despite the advances in pathogenesis understanding and the introduction of novel treatment options, PTLD arising after alloHSCT remains a particularly challenging disease, and there is a need for consensus on how to treat rituximab-refractory cases. This review aims to explore the pathogenesis, risk factors, and treatment options of PTLD in the alloHSCT setting, finally focusing on adoptive immunotherapy options, namely EBV-specific cytotoxic T-lymphocytes (EBV-CTL) and chimeric antigen receptor T-cells (CAR T).

Recent Advances in Adult Post-Transplant Lymphoproliferative Disorder

PTLD is a rare but severe complication of hematopoietic or solid organ transplant recipients, with variable incidence and timing of occurrence depending on different patient-, therapy-, and transplant-related factors. The pathogenesis of PTLD is complex, with most cases of early PLTD having a strong association with Epstein-Barr virus (EBV) infection and the iatrogenic, immunosuppression-related decrease in T-cell immune surveillance. Without appropriate T-cell response, EBV-infected B cells persist and proliferate, resulting in malignant transformation. Classification is based on the histologic subtype and ranges from nondestructive hyperplasias to monoclonal aggressive lymphomas, with the most common subtype being diffuse large B-cell lymphoma-like PTLD. Management focuses on prevention of PTLD development, as well as therapy for active disease. Treatment is largely based on the histologic subtype. However, given lack of clinical trials providing evidence-based data on PLTD therapy-related outcomes, there are no specific management guidelines. In this review, we discuss the pathogenesis, histologic classification, and risk factors of PTLD. We further focus on common preventive and frontline treatment modalities, as well as describe the application of novel therapies for PLTD and elaborate on potential challenges in therapy.

Probable posttransplant lymphoproliferative disorder after pediatric living donor liver transplantation: Is a biopsy still needed?

Posttransplant lymphoproliferative disorder (PTLD) is a complication of solid organ transplantation and is associated with Epstein-Barr virus (EBV). Recently, EBV-related PTLD was defined as probable PTLD or proven PTLD. Probable PTLD involves significant lymphadenopathy, hepatosplenomegaly, or other end-organ manifestations, without a histological diagnosis, together with significant EBV DNAemia. Proven PTLD is the detection of EBV-encoded proteins in a tissue specimen, together with symptoms and/or signs originating from the affected organ. Probable PTLD after pediatric liver transplantation has not been well documented. Therefore, here, we aimed to describe cases of five pediatric patients with probable PTLD after liver transplantation, who were successfully treated with preemptive immunosuppression reduction with or without rituximab. All five patients (age range, 1-4 years; two girls and three boys) had EBV DNAemia. Three patients developed probable PTLD within 12 months of transplantation. Further, three patients had a significantly high EBV viral load, but the other two patients with lymphadenopathy and end-organ manifestation had a relatively low EBV viral load. Early onset pediatric PTLD with significant EBV DNAemia is almost universally EBV-related. Biopsy was not performed in any patient due to the relative inaccessibility of the lesion and young age of the patients. If the patient's symptoms are too mild, if excisional biopsy is too difficult to perform, or if the patient is too sick to undergo an invasive procedure, initiating preemptive treatment without a histological diagnosis could be the treatment option.

Assessing and restoring adaptive immunity to HSV, VZV, and HHV-6 in solid organ and hematopoietic cell transplant recipients

BACKGROUND

Herpes simplex virus (HSV) 1 and 2, varicella zoster virus (VZV), and human herpesvirus 6 (HHV-6) cause severe infections in immunocompromised hosts. Interventions to optimize virus-specific adaptive immunity may have advantages over antivirals in the prophylaxis and treatment of these infections.

OBJECTIVES

We sought to review adaptive immune responses and methods for assessing and replenishing cellular and humoral immunity to HSV, VZV, and HHV-6 in solid organ transplant and hematopoietic cell transplant recipients.

SOURCES

We searched PubMed for relevant studies on immune responses to HSV, VZV, and HHV-6 as well as studies describing methods for evaluating and restoring cell-mediated immunity to other double-stranded DNA viruses in transplant recipients. Recent studies, randomized controlled trials, and investigations highlighting key concepts in clinical virology were prioritized for inclusion.

CONTENT

We describe the mechanisms of adaptive immunity to HSV, VZV, and HHV-6 and limitations of antivirals as prophylaxis and treatment for these infections in solid organ transplant and hematopoietic cell transplant recipients. We review methods for measuring and restoring cellular immunity to double-stranded DNA viruses; their potential applications to management of HSV, VZV, and HHV-6 in immunocompromised hosts; and barriers to clinical use. Vaccination and virus-specific T cell therapies are discussed in detail.

IMPLICATIONS

The growing repertoire of diagnostic and therapeutic techniques focused on virus-specific adaptive immunity provides a novel approach to management of viral infections in transplant recipients. Investigations to optimize such interventions specifically in HSV, VZV, and HHV-6 are needed.

Diagnosis and management of AML in adults: 2022 recommendations from an international expert panel on behalf of the ELN

The 2010 and 2017 editions of the European LeukemiaNet (ELN) recommendations for diagnosis and management of acute myeloid leukemia (AML) in adults are widely recognized among physicians and investigators. There have been major advances in our understanding of AML, including new knowledge about the molecular pathogenesis of AML, leading to an update of the disease classification, technological progress in genomic diagnostics and assessment of measurable residual disease, and the successful development of new therapeutic agents, such as FLT3, IDH1, IDH2, and BCL2 inhibitors. These advances have prompted this update that includes a revised ELN genetic risk classification, revised response criteria, and treatment recommendations.

High Predictive Value of the Soluble ZEBRA Antigen (Epstein-Barr Virus Trans-Activator Zta) in Transplant Patients with PTLD

The ZEBRA (Z EBV replication activator) protein is the major transcription factor of EBV, expressed upon EBV lytic cycle activation. An increasing body of studies have highlighted the critical role of EBV lytic infection as a risk factor for lymphoproliferative disorders, such as post-transplant lymphoproliferative disease (PTLD). We studied 108 transplanted patients (17 PTLD and 91 controls), retrospectively selected from different hospitals in France and in the Netherlands. The majority of PTLD were EBV-positive diffuse large B-cell lymphomas, five patients experienced atypical PTLD forms (EBV-negative lymphomas, Hodgkin’s lymphomas, and T-cell lymphomas). Fourteen patients among the seventeen who developed a pathologically confirmed PTLD were sZEBRA positive (soluble ZEBRA, plasma level above 20 ng/mL, measured by an ELISA test). The specificity and positive predictive value (PPV) of the sZEBRA detection in plasma were 98% and 85%, respectively. Considering a positivity threshold of 20 ng/mL, the sensitivity of the sZEBRA was 82.35% and the specificity was 94.51%. The mean of the sZEBRA values in the PTLD cases were significantly higher than in the controls (p < 0.0001). The relevance of the lytic cycle and, particularly, the role of ZEBRA in lymphomagenesis is a new paradigm pertaining to the prevention and treatment strategies for PTLD. Given the high-specificity and the predictive values of this test, it now appears relevant to investigate the lytic EBV infection in transplanted patients as a prognostic biomarker.

A Simple-to-Perform ifn-γ mRNA Gene Expression Assay on Whole Blood Accurately Appraises Varicella Zoster Virus-Specific Cell-Mediated Immunity After Allogeneic Hematopoietic Stem Cell Transplantation

Herpes zoster, which is due to the reactivation of Varicella zoster virus (VZV), is a leading cause of morbidity after allogeneic hematopoietic stem cell transplantation (allo-HSCT). While cell-mediated immunity (CMI) is critical to inhibiting VZV reactivation, CMI is not routinely assessed due to a lack of reliable tests. In this study, we aimed to evaluate VZV-specific CMI among allo-HSCT recipients (n = 60) and healthy individuals (HI, n = 17) through a panel of three immune functional assays after ex vivo stimulation by VZV antigen: quantification of (i) IFN-γ release in the supernatants, (ii) T-cell proliferation after a 7-day stimulation of peripheral blood mononuclear cells (PBMC), and (iii) measurement of the ifn-γ mRNA gene expression level after 24 h of stimulation of a whole-blood sample. VZV responsiveness was defined according to IFN-γ release from VZV-stimulated PBMC. Upon VZV stimulation, we found that allo-HSCT recipients at a median time of 6 [5-8] months post-transplant had lower IFN-γ release (median [IQR], 0.34 [0.12–8.56] vs. 409.5 [143.9–910.2] pg/ml, P <.0001) and fewer proliferating T cells (0.05 [0.01–0.57] % vs. 8.74 [3.12–15.05] %, P <.0001) than HI. A subset of allo-HSCT recipients (VZV-responders, n = 15/57, 26%) distinguished themselves from VZV-non-responders (n = 42/57, 74%; missing data, n = 3) by higher IFN-γ release (80.45 [54.3–312.8] vs. 0.22 [0.12–0.42] pg/ml, P <.0001) and T-cell proliferation (2.22 [1.18–7.56] % vs. 0.002 [0.001–0.11] %, P <.0001), suggesting recovery of VZV-specific CMI. Interestingly, VZV responders had a significant fold increase in ifn-γ gene expression, whereas ifn-γ mRNA was not detected in whole blood of VZV-non-responders (P <.0001). This study is the first to suggest that measurement of ifn-γ gene expression in 24-h-stimulated whole blood could be an accurate test of VZV-specific CMI. The routine use of this immune functional assay to guide antiviral prophylaxis at an individual level remains to be evaluated.

Population Pharmacokinetics of Intravenous Acyclovir in Oncologic Pediatric Patients

Background: Acyclovir represents the first-line prophylaxis and therapy for herpes virus infections. However, its pharmacokinetics in children exposes them to the risk of ineffective or toxic concentrations. The study was aimed at investigating the population pharmacokinetics (POP/PK) of intravenous (IV) acyclovir in oncologic children.

Methods: Patients (age, 8.6 ± 5.0 years, 73 males and 47 females) received IV acyclovir for prophylaxis (n = 94) and therapy (n = 26) under a therapeutic drug monitoring (i.e., minimum and maximal plasma concentrations, >0.5 and <25 mg/L, respectively). Plasma concentrations were fitted by nonlinear mixed effect modeling and a simulation of dosing regimens was performed. Findings were stratified according to an estimated glomerular filtration rate (eGFR) threshold of 250 ml/min/1.73 m².

Results: The final 1-compartment POP/PK model showed that eGFR had a significant effect on drug clearance, while allometric body weight influenced both clearance and volume of distribution. The population clearance (14.0 ± 5.5 L/h) was consistent across occasions. Simulation of standard 1-h IV infusion showed that a 10-mg/kg dose every 6 h achieved target concentrations in children with normal eGFR (i.e., ≤250 ml/min/1.73 m²). Increased eGFR values required higher doses that led to an augmented risk of toxic peak concentrations. On the contrary, simulated prolonged (i.e., 2 and 3-h) or continuous IV infusions at lower doses increased the probability of target attainment while reducing the risk of toxicities.

Conclusion: Due to the variable pharmacokinetics of acyclovir, standard dosing regimens may not be effective in some patients. Prospective trials should confirm the therapeutic advantage of prolonged and continuous IV infusions

Antiviral Therapeutics in Pediatric Transplant Recipients

Recipients of solid organ and hematopoietic stem cell transplantation undergo substantial immune suppression, placing them at risk for opportunistic viral infection. Few randomized controlled trials have been dedicated to the treatment of viral infections in children, and current practices are extrapolated from data generated from adult patients. Here we discuss the prevention and treatment of viral infections using available antiviral drugs, as well as novel agents that may provide benefit to pediatric patients in the future.

Donor activating killer cell immunoglobulin-like receptors genes correlated with Epstein-Barr virus reactivation after haploidentical haematopoietic stem cell transplantation

Natural killer (NK) cells exert anti-viral effects after haematopoietic stem cell transplantation (HSCT). The balance between inhibition and activation of NK cells determined by the inherited repertoire of killer cell immunoglobulin-like receptors (KIR) genes may influence Epstein-Barr virus (EBV) reactivation after transplantation. To evaluate the relative contributions of KIR genotypes to EBV reactivation, we prospectively enrolled 300 patients with malignant haematological disease who were suitable for haploidentical HSCT. Univariate analysis showed that donors with KIR2DS1, KIR2DS3 or KIR3DS1 genes were associated with an increased risk of EBV reactivation [hazard ratio (HR) 1·86, 95% confidence interval (CI) 1·19-2·9, P = 0·0067; HR 1·78, 95% CI 1·07-2·97, P = 0·027; HR 1·86, 95% CI 1·19-2·91, P = 0·0065 respectively]. Multivariate analysis revealed that the presence of KIR2DS1, KIR2DS3 or KIR3DS1 genes was associated with increased EBV reactivation after HSCT. This effect was more evident in the absence of the cognate ligands for the corresponding activating receptors. Our present data firstly showed that donors with activating KIR genes, specifically activating KIR2DS1, KIR2DS3 and KIR3DS1, had an increased risk of EBV reactivation. Precaution for patients whose donors carry activating genes will help prevent EBV reactivation and improve patient prognosis after HSCT.

Infection risk and prophylaxis in patients with lymphoid cancer

Infections are a common cause of morbidity and mortality in patients with lymphoid cancer. With evolving cancer therapeutics, including new targeted and immunotherapies, clinicians need to be aware of additional risk factors and infections that may arise in patients treated with these agents. This "How I Treat" article will highlight fundamental issues including risk factors for infection, infectious diseases screenings and antimicrobial prophylaxis recommendations in patients with lymphoid cancers. We present 4 scenarios of patients with lymphoid cancers with varied infections and describe a treatment approach based on a combination of evidence-based data and experience, as there are limitations in objective infection data especially with newer agents. The goal of this discussion is to provide a framework for institutions and health care providers to develop their own approach in preventing and treating infections in patients with lymphoid cancer.

Validation of a Post-Transplant Lymphoproliferative Disorder Risk Prediction Score and Derivation of a New Prediction Score Using a National Bone Marrow Transplant Registry Database

BACKGROUND

We externally validated Fujimoto's post-transplant lymphoproliferative disorder (PTLD) scoring system for risk prediction by using the Taiwan Blood and Marrow Transplant Registry Database (TBMTRD) and aimed to create a superior scoring system using machine learning methods.

MATERIALS AND METHODS

Consecutive allogeneic hematopoietic cell transplant (HCT) recipients registered in the TBMTRD from 2009 to 2018 were included in this study. The Fujimoto PTLD score was calculated for each patient. The machine learning algorithm, least absolute shrinkage and selection operator (LASSO), was used to construct a new score system, which was validated using the fivefold cross-validation method.

RESULTS

We identified 2,148 allogeneic HCT recipients, of which 57 (2.65%) developed PTLD in the TBMTRD. In this population, the probabilities for PTLD development by Fujimoto score at 5 years for patients in the low-, intermediate-, high-, and very-high-risk groups were 1.15%, 3.06%, 4.09%, and 8.97%, respectively. The score model had acceptable discrimination with a C-statistic of 0.65 and a near-perfect moderate calibration curve (HL test p = .81). Using LASSO regression analysis, a four-risk group model was constructed, and the new model showed better discrimination in the validation cohort when compared with The Fujimoto PTLD score (C-statistic: 0.75 vs. 0.65).

CONCLUSION

Our study demonstrated a more comprehensive model when compared with Fujimoto's PTLD scoring system, which included additional predictors identified through machine learning that may have enhanced discrimination. The widespread use of this promising tool for risk stratification of patients receiving HCT allows identification of high-risk patients that may benefit from preemptive treatment for PTLD.

IMPLICATIONS FOR PRACTICE

This study validated the Fujimoto score for the prediction of post-transplant lymphoproliferative disorder (PTLD) development following hematopoietic cell transplant (HCT) in an external, independent, and nationally representative population. This study also developed a more comprehensive model with enhanced discrimination for better risk stratification of patients receiving HCT, potentially changing clinical managements in certain risk groups. Previously unreported risk factors associated with the development of PTLD after HCT were identified using the machine learning algorithm, least absolute shrinkage and selection operator, including pre-HCT medical history of mechanical ventilation and the chemotherapy agents used in conditioning regimen.

Outcomes of haploidentical bone marrow transplantation in patients with severe aplastic anemia-II that progressed from non-severe acquired aplastic anemia

Severe aplastic anemia II (SAA-II) progresses from non-severe aplastic anemia (NSAA). The unavailability of efficacious treatment has prompted the need for haploidentical bone marrow transplantation (haplo-BMT) in patients lacking a human leukocyte antigen (HLA)-matched donor. This study aimed to investigate the efficacy of haplo-BMT for patients with SAA-II. Twenty-two patients were included and followed up, and FLU/BU/CY/ATG was used as conditioning regimen. Among these patients, 21 were successfully engrafted, 19 of whom survived after haplo-BMT. Four patients experienced grade II-IV aGvHD, including two with grade III-IV aGvHD. Six patients experienced chronic GvHD, among whom four were mild and two were moderate. Twelve patients experienced infections during BMT. One was diagnosed with post-transplant lymphoproliferative disorder and one with probable EBV disease, and both recovered after rituximab infusion. Haplo-BMT achieved 3-year overall survival and disease-free survival rate of 86.4% ± 0.73% after a median follow-up of 42 months, indicating its effectiveness as a salvage therapy. These promising outcomes may support haplo-BMT as an alternative treatment strategy for patients with SAA-II lacking HLA-matched donors.

Association between Antiviral Prophylaxis and Cytomegalovirus and Epstein-Barr Virus DNAemia in Pediatric Recipients of Allogeneic Hematopoietic Stem Cell Transplant

Background: Epstein–Barr virus (EBV) and cytomegalovirus (CMV) infections can have serious consequences during the period of aplasia and lymphopenia following hematopoietic stem cell transplantation (HSCT). Large pediatric cohort studies examining the effect of antiviral prophylaxis against these viruses are scarce. The present study aimed to analyse the potential effect of antiviral prophylaxis (acyclovir and famciclovir) on active post-transplant EBV and CMV infection in a pediatric cohort of allogeneic HSCT recipients. Methods: We used data from the TREASuRE cohort, consisting of 156 patients who had a first allogeneic HSCT, enrolled in four pediatric centers in Canada between July 2013 and March 2017. Follow-up was performed from the time of transplant up to 100 days post-transplant. Adjusted hazard ratio (HR) with 95% confidence intervals (CI) for the association between antiviral prophylaxis with acyclovir and/or famciclovir and EBV and CMV DNAemia was estimated using multivariate Cox regression models. Results: The post-transplant cumulative incidence of EBV and CMV DNAemia at 100 days of follow-up were, respectively, 34.5% (95% CI: 27.6–42.6) and 19.9% (95% CI: 14.5–27.1). For acyclovir, the adjusted hazard ratio (HR) for CMV and EBV DNAemia was 0.55 (95% CI: 0.24–1.26) and 1.41 (95% CI: 0.63–3.14), respectively. For famciclovir, the adjusted HR were 0.82 (95% CI: 0.30–2.29) and 0.79 (95% CI: 0.36–1.72) for CMV and EBV DNAemia, respectively. Conclusion: The antivirals famciclovir and acyclovir did not reduce the risk of post-transplant CMV and EBV DNAemia among HSCT recipients in our pediatric population.

The time-dependent effects of early-onset Epstein-Barr viremia on adult acute leukemia patients following allo-HSCT with ATG-containing MAC regimen

Epstein-Barr virus (EBV) viremia is a common complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The purpose of this study was to evaluate the impacts of early-onset EBV viremia in acute leukemia (AL) patients who underwent allo-HSCT with anti-thymocyte globulin (ATG)-containing myeloablative conditioning (MAC) regimen. Two hundred and ninety-six patients were included between January 2013 and December 2015. In 126 patients (42.6%) who developed early-onset EBV viremia, with a median time of 48 (range 18~99) days after allo-HSCT. The cumulative incidence of EBV viremia at 30 and 90 days after allo-HSCT were 4.1 and 39.9%, respectively. Prognostic analysis showed that the adjusted overall survival in early-EBV^pos group was significantly lower than early-EBV^neg group within the first 26.7 months after allo-HSCT [hazard ratio (HR), 1.63, P = 0.012], but significantly higher than those afterward (after 26.7 months: HR 0.11, P = 0.035); for the adjusted event-free survival, early-EBV^pos group was significantly inferior in early-EBV^pos group within the first 10.8 months after transplantation (HR: 1.55, P = 0.042), and this adverse effect was not detected any more after 10.8 months (HR: 0.58, P = 0.107). Compared with early-EBV^neg group after adjusting by aGVHD and CMV viremia, HR for death from transplant-related mortality was 2.78-fold higher in patients with early-EBV viremia in piecewise constant Cox analysis (P = 0.006), and this adverse effect was not detected any more after the cut-point time (HR: 0.67, P = 0.361). No differences in terms of relapse and relapse mortality were observed between early-EBV^pos and early-EBV^neg group (P > 0.05). In conclusion, the impacts on transplant outcomes of early-EBV viremia were time-dependent, which may help to optimize management strategies for early-EBV viremia after allo-HSCT, especially in AL patients with ATG-containing MAC regimen.

Optimising Antimicrobial Selection and Duration in the Treatment of Febrile Neutropenia in Children

Febrile neutropenia (FN) is a frequent complication of cancer treatment in children. Owing to the potential for overwhelming bacterial sepsis, the recognition and management of FN requires rapid implementation of evidenced-based management protocols. Treatment paradigms have progressed from hospitalisation with broad spectrum antibiotics for all patients, through to risk adapted approaches to management. Such risk adapted approaches aim to provide safe care through incorporating antimicrobial stewardship (AMS) principles such as implementation of comprehensive clinical pathways incorporating de-escalation strategies with the imperative to reduce hospital stay and antibiotic exposure where possible in order to improve patient experience, reduce costs and diminish the risk of nosocomial infection. This review summarises the principles of risk stratification in FN, the current key considerations for optimising empiric antimicrobial selection including knowledge of antimicrobial resistance patterns and emerging technologies for rapid diagnosis of specific infections and summarises existing evidence on time to treatment, investigations required and duration of treatment. To aid treating physicians we suggest the key features based on current evidence that should be part of any FN management guideline and highlight areas for future research. The focus is on treatment of bacterial infections although fungal and viral infections are also important in this patient group.

Determination and Role of Epstein-Barr Virus in Patients With Lymphoproliferative Disorders

INTRODUCTION

Epstein-Barr virus (EBV) is associated with different types of human malignancies, including Burkitt lymphoma, nasopharyngeal carcinoma, and lymphomas. We retrospectively investigated the presence of EBV-DNA by real-time PCR in clinical samples of patients diagnosed as having hematologic malignancies while investigating the cause of lymphoproliferative disorders, and investigated its relationship to clinical manifestations.

PATIENTS AND METHODS

Fifty clinical samples sent to Gazi University's hematology clinics between November 2013 and March 2018 were included. EBV-DNA was investigated by real-time PCR method, and EBV-IgM and EBV-IgG antibodies were investigated by ELISA.

RESULTS

Fifty serum samples were investigated, and 10% (5/50) EBV-DNA positivity was determined in patients. Of the 5 patients with EBV-DNA positivity, 2 had acute lymphoblastic leukemia, 1 lymphoma, 1 T-cell lymphoma, and 1 B-cell lymphoma. Concomitant EBV-DNA and viral capsid antigen (VCA)-IgM positivity was not detected. The VCA-lgM test results of the all EBV-DNA-positive patients were negative and VCA-IgG positive (except for 1 patient). Regarding virus load, of the 5 samples, 2, 1, 1, and 1 of the samples had a virus load of 10², 10³, 10⁴, and 10⁵ copies/mL, respectively.

CONCLUSION

EBV infection is threatening in patients with hematologic malignancies and are diagnosed by serologic and molecular methods. As a result of the study, we suggest that the detection of EBV-DNA by real-time PCR in patients being admitted with lymphoproliferative diseases and diagnosed as acute lymphoblastic leukemia and lymphomas may be useful in follow-up and treatment.

Post-transplantation lymphoproliferative disorder after haematopoietic stem cell transplantation

Post-transplantation lymphoproliferative disorder (PTLD) is a severe complication of haematopoietic stem cell transplantation (HSCT), occurring in a setting of immune suppression and dysregulation. The disease is in most cases driven by the reactivation of the Epstein-Barr virus (EBV), which induces B cell proliferation through different pathomechanisms. Beyond EBV, many factors, variably dependent on HSCT-related immunosuppression, contribute to the disease development. PTLDs share several features with primary lymphomas, though clinical manifestations may be different, frequently depending on extranodal involvement. According to the WHO classification, histologic examination is required for diagnosis, allowing also to distinguish among PTLD subtypes. However, in cases of severe and abrupt presentation, a diagnosis based on a combination of imaging studies and EBV-load determination is accepted. Therapies include prophylactic and pre-emptive interventions, aimed at eradicating EBV proliferation before symptoms onset, and targeted treatments. Among them, rituximab has emerged as first-line option, possibly combined with a reduction of immunosuppression, while EBV-specific cytotoxic T lymphocytes are effective and safe alternatives. Though prognosis remains poor, survival has markedly improved following the adoption of the aforementioned treatments. The validation of innovative, combined approaches is the future challenge.

Management of Herpesvirus Infections in Hematopoietic Cell Transplant Recipients

Following primary infection, herpesviruses establish latency in infected individuals in the host cells and may reactivate upon external stimuli and during periods of immunosuppression. The objective of this paper was to the present current strategies on preventive and therapeutic management of infections with herpesviruses in recipients of hematopoietic cell transplantation. Strategies of antiviral management include prophylaxis, pre-emptive treatment and targeted treatment. Empirical therapy is not used in antiviral strategies. Prophylaxis can be done at universal (preventive strategy) and specific level. Universal prophylaxis includes non-pharmacologic methods of prevention of infection or reactivation. Risk-adapted specific prophylaxis includes use of specific antivirals or cellular therapy or other specific methods in order to prevent specific infection, in high-risk groups. Pre-emptive therapy means use of therapeutic approaches in asymptomatic infection, detected by a screening assay. Targeted therapy is used in established specific viral end-organ infections. The following sections of the paper refer to prophylaxis and treatment strategies, respectively, against CMV, EBV, HSV, VZV, HHV-6, HHV-7, and HHV-8 after allogeneic hematopoietic cell transplantation.

Considerations on antimicrobial prophylaxis in patients with lymphoproliferative diseases: A SEIFEM group position paper

The therapeutic armamentarium for the treatment of patients with lymphoproliferative diseases has grown considerably over the most recent years, including a large use of new immunotherapeutic agents. As a consequence, the epidemiology of infectious complications in this group of patients is poorly documented, and even more importantly, the potential benefit of antimicrobial prophylaxis remains a matter of debate when considering the harmful effect from the emergence of multidrug resistant pathogens. The present position paper is addressed to all hematologists treating patients affected by lymphoproliferative malignancies with the aim to provide clinicians with a useful tool for the prevention of bacterial, fungal and viral infections.

Systemic viral infection in children receiving chemotherapy for acute leukemia

Systemic viral diseases frequently occur in allogeneic hematopoietic stem cell transplantation, but data in children receiving chemotherapy for acute leukemia are scarce. We therefore collected and analyzed the published data on symptomatic infection from cytomegalovirus, herpes simplex virus, varicella zoster virus, parvovirus B19, or adenovirus in pediatric acute leukemia. Reports on 68 children were identified, of whom 16 patients have died from the infection. Further studies have to (1) evaluate the true incidence of these infections in pediatric acute leukemia, (2) their impact on outcome, and (3) whether a subpopulation of patients could benefit from screening and prophylactic strategies.