Cytomegalovirus (CMV) infection and risk of mortality in allogeneic hematopoietic stem cell transplantation (Allo-HSCT): A systematic review, meta-analysis, and meta-regression analysis

What intensivists need to know about cytomegalovirus infection in immunocompromised ICU patients

PURPOSE

Advances in therapeutic care are leading to an increase in the number of patients living with overt immunosuppression. These patients are at risk of cytomegalovirus (CMV) infection and disease that can lead to or develop during ICU admission. This manuscript aims to describe the clinical presentation, risk factors, and management of CMV infection and disease in this patient population.

METHODS

We conducted a literature search in PubMed up to April 2024, focusing on CMV infection and disease in patients with overt immunosuppression (hematopoietic stem cell and solid organ transplantation, solid or hematologic malignancies, HIV infection, immunosuppressive drugs, including corticosteroids, and primary immunodeficiencies) admitted to the intensive care unit (ICU). As there is limited ICU-specific data on CMV in immunosuppressed patients, many of the findings were extrapolated from the general literature.

RESULTS

CMV infection and disease in immunocompromised critically ill patients is associated with increased mortality and presents significant management challenges. Clinical manifestations are diverse, shaped by the underlying immune deficiency and primary disease. Pneumonia and encephalitis are among the most severe CMV end-organ diseases. CMV infection may also increase the risk of secondary infections and induce life-threatening conditions, such as thrombotic microangiopathy. Importantly, CMV reactivation is not synonymous with CMV disease, and qPCR testing of body fluids cannot reliably differentiate between viral shedding and tissue-invasive infection, which requires histopathological confirmation. Ganciclovir is commonly the first-line anti-viral, though maribavir shows potential for patients unresponsive to other antivirals. Identifying patients who require prophylactic or preemptive antiviral therapy is essential.

CONCLUSIONS

CMV infection and disease in critically ill immunocompromised patients pose a unique challenge for intensivists. The broad spectrum of clinical presentations and the difficulty in distinguishing CMV-related symptoms from other causes require a high level of clinical suspicion. Accurate interpretation of nucleic acid load levels and careful evaluation of CMV's pathogenic role when it is found are critical. Further studies focusing specifically on CMV infection and disease in critically ill immunocompromised patients are needed to optimize management strategies.

Risk and impact of cytomegalovirus infection in lymphoma patients treated with bendamustine

Bendamustine is used to treat lymphoma with excellent efficacy but is known for its immunosuppressive effect. Cytomegalovirus (CMV) reactivation after bendamustine use has been reported. We aim to address the impact of CMV infection in lymphoma patients treated with bendamustine-containing regimens. We retrospectively analyzed lymphoma patients at Taipei Veterans General Hospital in Taiwan between September 1, 2010, and April 30, 2022. Clinically significant CMV infection (CS-CMVi) was defined as the first CMV reactivation after bendamustine use necessitating CMV therapy. Patients' baseline characteristics and laboratory data were recorded. The primary endpoint of the study was CS-CMVi. A time-dependent covariate Cox regression model was used to estimate the risk factors of CS-CMVi and mortality. A total of 211 lymphoma patients treated with bendamustine were enrolled. Twenty-seven (12.8%) had CS-CMVi. The cumulative incidence was 10.1 per 100 person-years during the three-year follow-up period. In the multivariate analysis, lines of therapy before bendamustine ≥ 1 (95% CI 1.10-24.76), serum albumin < 3.5 g/dL (95% CI 2.63-52.93), and liver disease (95% CI 1.51-28.61) were risk factors for CS-CMVi. In conclusion, CS-CMVi (95% confidence interval [CI] 1.23-10.73) was one of the major independent risk factors of mortality. Lines of therapy before bendamustine ≥ 1, hypoalbuminemia, and liver disease were risk factors for CS-CMVi in lymphoma patients treated with bendamustine.

Cytomegalovirus infection and disease in systemic lupus erythematosus patients at a high-complexity hospital in southwestern Colombia

Cytomegalovirus (CMV) infection and disease is a condition usually described in immunocompromised patients, but among them, those with connective tissue diseases are poorly represented. Here we present the clinical, laboratory characteristics, management and outcomes of systemic lupus erythematosus (SLE) patients who presented with a CMV infection/disease to a high complexity hospital in southwestern Colombia between 2011 and 2020. 16 SLE patients were found to have a CMV infection. SLE was predominantly characterized by renal involvement (10 patients; 62.50%), and 14 patients (87.5%) were receiving steroids previous to the CMV infection. The entire sample required hospital admission, mainly related to acute kidney injury, and nine patients were admitted to the intensive care unit (ICU). Gastrointestinal organ damage was the most common CMV disease manifestation. All patients received ganciclovir, five of them (31.25%) suffered from septic shock, and seven (43.75%) died. Age ≥38 years and the presence of septic shock at admission were correlated to the mortality outcome. To our knowledge, this is the first publication evaluating SLE patients with CMV infection/disease in a Colombian population.

Real-World Safety and Effectiveness of Letermovir in Patients Undergoing Allogenic Hematopoietic Stem Cell Transplantation: Final Results of Post-Marketing Surveillance in Japan

BACKGROUND AND OBJECTIVE

Cytomegalovirus (CMV) is a common opportunistic infection after allogenic hematopoietic stem cell transplantation (allo-HSCT). Letermovir, an inhibitor of CMV DNA terminase, is approved for CMV prophylaxis in allo-HSCT patients. We report the final results of post-marketing surveillance of letermovir in Japan.

METHODS

The case report forms were drafted in part by the Japanese Data Center for Hematopoietic Cell Transplantation using data elements in the Transplant Registry Unified Management Program and sent to individual HSCT centers to decrease the burden of reporting. Hematopoietic stem cell transplantation patients who received letermovir between May 2018 and May 2022 were registered. Data collected included physician-assessed adverse events/adverse drug reactions and clinical effectiveness (development of CMV disease, CMV antigen status, and use of preemptive therapy).

RESULTS

A total of 821 HSCT patients were included in the safety analyses. Adverse drug reactions occurred in 11.33% of patients, with serious adverse drug reactions in 3.05%. The five most common adverse drug reactions were nausea (1.58%), renal impairment (1.46%), and acute graft versus host disease, CMV test positive, and hepatic function abnormal (0.61% each). A total of 670 patients were eligible for effectiveness analyses. Among these patients, 16.57% and 28.66% required preemptive therapy through week 14 and week 48, respectively. In addition, relatively few patients developed CMV disease throughout the follow-up period (1.34% at week 14 and 3.85% at week 48).

CONCLUSIONS

This final analysis of post-marketing surveillance with up to 48 weeks follow-up period in Japan provides further evidence supporting the safety profile and effectiveness of letermovir for CMV prophylaxis in patients undergoing allo-HSCT in real-world settings.

Predictors of cytomegalovirus reactivation after allogeneic hematopoietic cell transplantation: Insights from a real-world experience

BACKGROUND

We aimed to investigate factors associated with cytomegalovirus (CMV) viremia and CMV disease and its impact on post-transplant outcomes including overall survival (OS) following allogeneic hematopoietic stem cell transplantation (Allo-SCT).

METHODS

We conducted a single-center retrospective study including 452 Allo-SCT recipients (matched unrelated donor, MUD 61%; haploidentical, haplo 39%) from 2016 to 2021. Data were analyzed using SPSS v28. Descriptive (chi-square and t-test), Kaplan-Meier and regression analyses were conducted.

RESULTS

The median age was 57 years. Sixty-one percent were males and 84.3% were Caucasians. CMV serostatus was positive in 59.1% of recipients. The median follow-up was 24.4 months. CMV viremia and CMV disease were observed in 181 (40%) and 32 (7%) patients, respectively. Among CMV seropositive recipients, 65% developed CMV viremia and 11% were noted to have CMV disease compared to 4% and 1% in seronegative recipients, respectively (p < 0.001). Patients with CMV disease had significantly lower OS than those without CMV disease (median 14.1 months vs. not reached, p = 0.024); however, OS was not associated with CMV viremia (median not reached in both groups, p = 0.640). Letermovir prophylaxis was used in 66% (n = 176/267) of CMV seropositive recipients, but no impact was observed on the incidence of CMV viremia or CMV disease and OS.

CONCLUSIONS

CMV disease leads to significantly inferior survival after an allogeneic hematopoietic cell transplantation. Recipient CMV seropositive status was associated with the risk of CMV viremia and CMV disease, and this was not abrogated with the use of Letermovir prophylaxis.

Letermovir Primary Cytomegalovirus Prophylaxis in Allogeneic Hematopoietic Cell Transplant Recipients: Real-Life Data from a University Hospital in Argentina

Background

Cytomegalovirus (CMV) infection remains the most common clinically significant infection after allogeneic hematopoietic stem cell transplantation (allo-HCT) and is associated with considerable morbidity and mortality.

Objectives

The present study was designed to describe and compare the incidence of untreated CMV reactivation (uCMVr), clinically significant infection (cs-CMVi) and disease (CMVd), as well as CMV-related hospitalization and outcome of allo-HCT patients, either treated with letermovir (LET) primary prophylaxis or managed with preemptive therapy (PET).

Methods

This is a prospective observational cohort study of adult CMV seropositive allo-HCT patients who either received primary prophylaxis with LET within the first 100 days after HCT or were managed with PET.

Results

The study population comprised 105 patients (28 in the LET group and 77 in the PET group). Compared to the PET group, patients in the LET group received more allo-HCT from alternative donors (54.5% vs. 82.14%, P=0.012). More than half of the patients in both groups were classified as high risk for CMVd. In the LET vs. PET group, cs-CMVi and CMVd developed respectively in 0 vs. 50 (64.94%), P=<0.0001, and 0 vs. 6 (7.79%), P=0.18. In the LET group, uCMVr occurred in 5 (17.8%) and were all considered blips. Hospital admissions related to cs-CMVi or CMVd in the PET group vs. LET group were 47 (61.04%) vs. 0, respectively, P=<0.0001. No differences were observed in 100-day mortality.

Conclusions

LET primary prophylaxis proved effective in preventing cs-CMVi and CMVd and reducing hospitalizations in allo-HCT adults. Blips can occur during prophylaxis and do not require LET discontinuation.

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).

The indirect effects of CMV reactivation on patients following allogeneic hematopoietic stem cell transplantation: an evidence mapping

Cytomegalovirus (CMV) reactivation following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a challenging problem, and the impact on the risk of overall mortality (OM) and non-relapse mortality (NRM) in patients following allo-HSCT is still controversial. Utilizing the evidence mapping method, we aimed to assess the effect of CMV infection on outcomes of patients post-transplantation and identify research gaps through systematic reviews (SRs) and clinical studies. PubMed, EMBASE, Web of Science, and Cochrane library databases were searched from inception until 5 July 2022 to identify relevant literature. After systematic literature screening and data extraction, evidence mapping of the effects of CMV reactivation on patients post-allo-HSCT was conducted. Three SRs and 22 clinical studies were included. In one SR, CMV reactivation was associated with an increased risk of mortality (HR 1.46; 95% CI, 1.24-1.72; P ≤ 0.001). In two SRs, CMV reactivation was associated with NRM. One SR reported CMV reactivation was potentially associated with significant protection against relapse in patients with acute myelocytic leukemia (AML), but no significant correlation with graft-versus-host disease (GVHD) was found. Lastly, in one SR CMV reactivation significantly increased the risk of invasive fungal disease (IFD). Most clinical articles reported that CMV reactivation increased the risk of renal dysfunction, poor graft function, re-hospitalization, and bacterial infections. CMV reactivation following allo-HSCT is associated with an increased risk of OM, NRM, IFD, and renal dysfunction, as well as a reduced risk of relapse in patients with AML.

Gaining Consensus Around Patient Risk Groups and Prognostic Profiles to Guide CMV Management Among Patients With Allogeneic Hematopoietic Stem Cell Transplant: Insights From a Delphi Panel With Hematopoietic Stem Cell Transplant Experts

INTRODUCTION

This study aimed to characterize patient risk groups and prognostic profiles to optimize clinical decision-making and guide appropriate medical cytomegalovirus (CMV) management among patients with allogeneic hematopoietic stem cell transplant (HSCT).

METHODS

Between 8/2021 and 2/2022, a 3-round modified Delphi study was conducted to generate consensus among 10 international experts in HSCT and infectious diseases. Experts were asked about treatment and prognoses for patients in 7 distinct clinical scenarios. Furthermore, experts were asked to risk-stratify patients by pre-/post-transplant characteristics. Consensus around opting for/against a treatment was observed if ≥75% or <25% of experts reported ≥50% likelihood to recommend or if treatments were ranked inside/outside the top 2 options and ≥75% of experts were within 1 SD of mean ranks.

RESULTS

Experts agreed on several unmet needs in CMV disease management post-HSCT, particularly avoidance of treatment-limiting toxicities with conventional CMV therapy and the emergence of both refractory and drug-resistant treatment failures. Experts considered CMV viral load, resistance profile, and route of administration as critical to treatment selection. For newer CMV therapeutic options, experts listed a lack of long-term use data, concerns over potential resistance, high cost, and limited availability as challenges restricting adoption and successful patient management.

CONCLUSIONS

Experts achieved consensus around patient risk stratifications and factors influencing therapeutic options. Recommendations emerging from this Delphi study may support practicing physicians when confronted with challenging CMV scenarios in patients with HSCT.

Clinical features and prognosis of systemic lupus erythematosus complicated by active cytomegalovirus infection: a retrospective cohort study

Objective

The aim of this study was to investigate the clinical traits and consequences of systemic lupus erythematosus (SLE) complicated by active cytomegalovirus (CMV) infection.

Methods

This retrospective review involved the examination of medical records for patients diagnosed with SLE who had an active CMV infection at the time of their discharge from Peking Union Medical College Hospital between June 2016 and December 2022. The consistency between plasma CMV deoxyribonucleic acid (DNA) viral load and pp65 antigenemia was analyzed using the chi-square test. Related factors for CMV disease in SLE complicated by active CMV infection patients were analyzed by univariate analysis and multivariable stepwise logistic regression. Cox hazards regression analysis was used to determine predictors for all-cause mortality and CMV recurrence within 3 months.

Results

A total of 206 patients were enrolled in this study. Of the 123 patients who were detected with both plasma CMV DNA viral load and pp65 antigenemia within an interval not exceeding 72 h, the consistency between plasma CMV DNA viral load and pp65 antigenemia was not good (Kappa = -0.304, p < 0.001). Plasma CMV DNA viral load ≥ 1,600 copies/mL [odds ratio (OR) 4.411, 95% CI 1.871-10.402, p = 0.001], current glucocorticoids dose (equivalent to prednisolone) ≥60 mg/d (OR 2.155, 95% CI 1.071-4.334, p = 0.031), and elevated alanine transaminase (OR 3.409, 95% CI 1.563-7.435, p = 0.002) were significant clinical clues indicating CMV disease in SLE. Multivariable Cox hazards regression analysis showed that CMV organ involvement [hazard ratio (HR) 47.222, 95% CI 5.621-396.689, p < 0.001], SLE multi-system involvement (HR 1.794, 95% CI 1.029-3.128, p = 0.039), and elevated hypersensitive C-reactive protein (hsCRP) (HR 5.767, 95% CI 1.190-27.943, p = 0.030) were independent risk factors for 3-month all-cause mortality. CMV organ involvement (HR 3.404, 95% CI 1.074-10.793, p = 0.037) was an independent risk factor for CMV recurrence within 3 months.

Conclusion

In SLE patients, plasma CMV DNA viral load seemed to have a higher value in the diagnosis of CMV disease; patients with CMV organ involvement, SLE multi-system involvement, and elevated hsCRP might have a higher risk of 3-month all-cause mortality; and patients with CMV organ involvement might have a higher risk of CMV recurrence within 3 months.

Donor aKIR genes influence the risk of EBV and CMV reactivation after anti-thymocyte globulin-based haploidentical hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) offers the highest curative potential for patients with hematological malignancies. Complications including infection, graft-versus-host disease (GVHD), and relapse reflect delayed or dysregulated immune reconstitution. After transplantation, NK cells rapidly reconstitute and are crucial for immune surveillance and immune tolerance. NK cell function is tightly regulated by killer immunoglobin-like receptors (KIRs). Previous studies have revealed that donor KIRs, especially some activated KIRs (aKIRs) are closely related to transplant outcomes. Here, we performed a retrospective study, including 323 patients who received haploidentical (haplo) HSCT in our center. In univariate analysis, donor KIR2DS1, KIR2DS3 and KIR3DS1 gene protected patients with lymphoid disease from Epstein-Barr virus (EBV) and cytomegalovirus (CMV) reactivation, while donor KIR2DS1, KIR2DS5 and KIR3DS1 gene conferred a higher risk of CMV reactivation for patients with myeloid disease. Multivariate analysis confirmed that donor telomeric (Tel) B/x and KIR2DS3 gene best protected patients with lymphoid disease from EBV (p = 0.017) and CMV reactivation (p = 0.004). In myeloid disease, grafts lacking Tel B/x and KIR2DS5 gene correlated with the lowest risk of CMV reactivation (p = 0.018). Besides, donor aKIR genes did not influence the rates of GVHD, relapse, non-relapse mortality (NRM) and overall survival (OS) in this study. The reactivation of EBV and CMV was associated with poor prognosis of haplo-HSCT. In conclusion, we found that donor aKIR genes might have a synergistic effect on CMV and EBV reactivation after haplo-HSCT. Whether the influence of donor aKIR genes varies with disease types remained to be studied.

Letermovir at a Prophylactic Dose for Cytomegalovirus Infection in Children Undergoing Allogeneic Hematopoietic Stem Cell Transplantation: A Single-Center Retrospective Study in Japan

Cytomegalovirus (CMV) infection is a major complication of hematopoietic stem cell transplantation (HSCT). Previous studies in adults demonstrated that letermovir prophylaxis for 100 d after HSCT reduces the occurrence of CMV infection; however, studies in children are limited. In this study, we aimed to examine the incidence of CMV infection in children who underwent allogeneic HSCT with prophylactic letermovir therapy. A single-center retrospective study was conducted among patients aged ≤17 who underwent allogeneic HSCT. We compared the cumulative incidence of CMV infection, mainly monitored by pp65-antigenemia, after HSCT between patients with and without letermovir prophylaxis (10-12 or 5-6 mg/kg/d when co-administered with cyclosporine) using Gray's test. We analyzed 79 patients with a median follow-up period of 126 d. The median age of these patients was 8.3 years (Interquartile range, 3.7-12.4). Prophylactic letermovir was used in 25 patients. Twenty-five patients developed CMV infection, and the cumulative incidence was 38.9% (95% confidence intervals, 25.0-52.5). The cumulative incidence of CMV infection was not significantly different between the letermovir and no-letermovir groups (33.1 vs. 36.6%, p = 0.228). Meanwhile, the cumulative incidence of CMV infection up to 100 d following HSCT was significantly lower in the letermovir group than in the no-letermovir group (8.0 vs. 32.8%, p = 0.026). Most patients experienced no noticeable adverse effects associated with letermovir; however, one patient discontinued letermovir because of nausea and anorexia. In conclusion, the results of this study suggest that letermovir prophylaxis against CMV infection may be effective in children without severe adverse effects.

Refractory cytomegalovirus infections in Chinese patients receiving allogeneic hematopoietic cell transplantation: a review of the literature

In the absence of prophylactic therapy, cytomegalovirus (CMV) viremia is a common complication following allogeneic hematopoietic cell transplantation (allo-HCT) and represents a significant cause of morbidity and mortality. Approximately 25% of allo-HCT happen in China, where the development and refinement of the 'Beijing protocol' has enabled frequent and increasing use of haploidentical donors. However, refractory CMV infection (an increase by >1 log10 in blood or serum CMV DNA levels after at least 2 weeks of an appropriately dosed anti-CMV medication) is more common among patients with haploidentical donors than with other donor types and has no established standard of care. Here, we review the literature regarding refractory CMV infection following allo-HCT in China.

Evidence supporting the use of therapeutic drug monitoring of ganciclovir in transplantation

PURPOSE OF REVIEW

This review describes current knowledge of ganciclovir (GCV) and valganciclovir (ValGCV) pharmacokinetic/pharmacodynamic characteristics, highlighting the likely contribution from host genetic factors to interpatient variability. The evidence and challenges surrounding optimization of drug dosing through therapeutic drug monitoring (TDM) are examined, with recommendations made.

RECENT FINDINGS

Pharmacokinetic studies of current dosing guidelines have shown high interindividual and intraindividual variability of GCV concentrations. This is sometimes associated with a slow decline in cytomegalovirus (CMV) viral load in some transplant recipients. A high incidence of GCV-associated myelosuppression has limited the use of this drug in the transplant setting. Patient groups identified to benefit from GCV TDM include pediatric patients, cystic fibrosis with lung transplantation, obese with kidney transplantation, and patients with fluctuating renal function or on hemodialysis. The emergence of refractory resistant CMV, particularly in immune compromised patients, highlights the importance of appropriate dosing of these antivirals. Host genetic factors need to be considered where recently, two host genes were shown to account for interpatient variation during ganciclovir therapy. Therapeutic Drug Monitoring has been shown to improve target antiviral-level attainment. The use of TDM may guide concentration-based dose adjustment, potentially improving virological and clinical outcomes. However, evidence supporting the use of TDM in clinical practice remains limited and further study is needed in the transplant cohort.

SUMMARY

Further studies examining novel biomarkers are needed to guide target concentrations in prophylaxis and treatment. The use of TDM in transplant recipients is likely to improve the clinical efficacy of current antivirals and optimize outcomes in transplant recipients.

High-dose aciclovir in CMV infection prophylaxis after allogeneic HSCT: a single-center long-term experience

There is only limited data on cytomegalovirus (CMV) prophylaxis with high-dose (HD) aciclovir after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We performed a retrospective analysis on a total of 179 patients who underwent their allo-HSCT with HD-aciclovir prophylaxis at our center. A clinically significant CMV infection (cs-CMVi) was observed in 56 (31%) cases with a median time of 49 (range 25-147) days after HSCT. A significantly higher CMV infection rate was observed in seropositive recipients with a seronegative donor (74%) compared to seropositive recipients with a seropositive donor, and seronegative recipients with seropositive and seronegative donors (24%, 18%, 7% respectively; p < 0.001). The CMV serostatus was the only significant risk factor for CMV infection in our analysis. CMV disease developed in three patients with CMV-related death in two cases. During HD-aciclovir prophylaxis, we did not observe any medical condition attributable to HD-aciclovir's adverse effects. Compared to published results, we observed a low incidence of cs-CMVi with HD-aciclovir prophylaxis in several patient subgroups, especially in seropositive recipients with a seropositive donor. With respect to the determined threshold, HD-aciclovir prophylaxis seems to have good efficacy in an intermediate cs-CMVi risk patients, but prospective randomized trials would be needed for definite conclusions.

Application of the ViroKey® SQ FLEX assay for detection of cytomegalovirus antiviral resistance

BACKGROUND

Cytomegalovirus (CMV) is a viral infection which establishes lifelong latency, often reactivating and causing disease in immunosuppressed individuals, including haematopoietic stem cell transplant (HSCT) recipients. Treatment can be problematic due to antiviral resistance which substantially increases the risk of patient mortality. Diagnostic testing capabilities for CMV antiviral resistance in Australia and elsewhere have traditionally relied on gene-specific Sanger sequencing approaches, however, are now being superseded by next generation sequencing protocols.

OBJECTIVE

Provide a snapshot of local mutations and explore the feasibility of the ViroKeyࣨ® SQ FLEX Genotyping Assay (Vela Diagnostics Pty Ltd) by examining sequencing success.

METHOD

Performed sequencing on adult (n = 38) and paediatric (n = 81) plasma samples, over a large range of viral loads (above and below the assay recommended threshold of ≥1,000 International Units (IU)/mL; noting most of our paediatric samples have loads <1,000 IU/mL).

RESULTS

Eleven test runs (including three repeat runs; 14 to 15 samples per run) were conducted, and four runs were deemed valid. The overall individual sample success rate for the four evaluable test runs was 71.2% (42/59 samples); 80.4% (37/46) samples ≥1,000 IU/mL were valid. Ten clinically important antiviral resistance mutations were detected, the most common being A594V in the UL97 gene, found in 6 (5%) samples.

CONCLUSIONS

A range of technical issues were experienced, however with improvement this platform could be a useful addition to routine pathology workflows, providing timely antiviral resistance results for patients undergoing HSCT.

Dynamics of polyclonal immuno-reconstitution after allogeneic transplant with post-transplant cyclophosphamide and letermovir

Cytomegalovirus (CMV) reactivations are strong stimulators of immune-reconstitution (IR) in hematopoietic stem cell transplantation (HSCT) recipients. Herein, we analyzed 317 CMV-seropositive consecutive patients (n = 109 letermovir, LTV; n = 208 no-LTV), undergoing HSCT with post-transplant cyclophosphamide (PTCy) and calcineurin inhibitor- (CNI) free graft-versus-host-disease (GvHD) prophylaxis. At day+90, median CD19+/mm3 was higher in LTV-cohort: 5.5 [0;439] versus 2 [0;294], p = 0.008; median CD3+/mm3 counts were lower in LTV-cohort, with no differences in CD4+, CD8+ and NK-cells. At day+180 median CD3+, CD4+ and CD8+/mm3 values were comparable between groups. Higher CD19+/mm3 counts were observed in LTV-cohort: 62 [0; 2983] versus 42 [0; 863]. Significantly higher median NK/mm3 values were seen in LTV-cohort: 225.5 [0;763] versus 163.5 [0;1181], p = 0.0003. The impact of LTV on B-cell IR at 3 months and NK-cell levels at 6 months was retained in multivariate analysis (p < 0.01), whereas the effect on T-cells was not confirmed. Moreover, we confirmed a significant reduction of clinically-relevant CMV, and moderate-to- severe chronic GvHD in LTV-cohort. Overall, in our study the use of LTV was associated with a slight improvement of B-cell and NK-cells reconstitution, with only minor impact on T-cell subsets, giving new insights on polyclonal IR for HSCT recipients in the LTV era.

CMV hyperimmune globulin as salvage therapy for recurrent or refractory CMV infection in children undergoing hematopoietic stem cell transplantation

Cytomegalovirus (CMV) is a major cause of allogeneic hematopoietic stem cell transplant (HSCT)-related morbidity and mortality. Treatment failure continues to be a major issue in patients with CMV infection due to both drug resistance and intolerance. This single-center brief retrospective analysis of a case series aims to investigate the safety and efficacy of CMV-hyperimmune globulin as salvage therapy for CMV infection in children undergoing HSCT. Fifteen pediatric patients received human CMV-specific immunoglobulin (CMVIG) between July 2018 and December 2021 as a salvage therapy for refractory or recurrent CMV infection. At the time of CMVIG prescription, eight children presented with recurrent CMV infection and seven with refractory CMV infection. The overall response rate was 67% at 50 days from the CMVIG administration [95% confidence interval (CI): 44-88]. Overall survival (OS) from CMVIG administration at 100 days was 87% (95% CI: 56-96), and OS from HSCT at 1 year was 80% (95% CI: 50-93). Four patients died, three unrelated to CMV infection and one due to CMV pneumonia. CMVIG as salvage therapy was well tolerated, and no infusion-related adverse events were observed.

Virus-Specific T Cells: Promising Adoptive T Cell Therapy Against Infectious Diseases Following Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) is a life-saving therapy for various hematologic disorders. Due to the bone marrow suppression and its long recovery period, secondary infections, like cytomegalovirus (CMV), Epstein-Bar virus (EBV), and adenovirus (AdV), are the leading causes of morbidity and mortality in HSCT cases. Drug resistance to the antiviral pharmacotherapies makes researchers develop adoptive T cell therapies like virus-specific T cell therapy. These studies have faced major challenges such as finding the most effective T cell expansion methods, isolating the expected subtype, defining the functionality of the end-cell population, product quality control, and clinical complications after the injection. This review discusses the viral infections after HSCT, T cells characteristics during chronic viral infection, application of virus-specific T cells (VSTs) for refractory infections, standard methods for producing VSTs and their limitation, clinical experiences on VSTs, focusing on outcomes and side effects that can be helpful in decision-making for patients and further researches.

Clinical application value of metagenomic second-generation sequencing technology in hematologic diseases with and without transplantation

Introduction

Hematological patients are at risk of infections. It is unknown whether the pathogenic microbial spectrum differs between HSCT and non-HSCT patients, and whether metagenomic next-generation sequencing (mNGS) of peripheral blood can be used as a substitute test specimen such as alveolar lavage.

Methods

A retrospective study was conducted to evaluate the clinical application value of mNGS in hematological patients with and without HSCT.

Results

Viruses were prevalent pathogens in both non-HSCT (44%) and HSCT (45%) patients, chiefly human cytomegalovirus and Epstein-Barr virus. In non-HSCT patients, Gram-negative bacilli accounted for 33% (predominantly Klebsiella pneumonia), and Gram-positive cocci accounted for 7% (predominantly Enterococcus faecium) of pathogens. However, in HSCT patients, Gram-negative bacilli accounted for 13% (predominantly Stenotrophomonas maltophilia), and Gram-positive cocci accounted for 24% (predominantly Streptococcus pneumonia) of pathogens. Mucor was the most common fungu s in two groups. The positive rate of pathogens by mNGS was 85.82%, higher than conventional detection (20.47%, P < 0.05). Mixed infection accounted for 67.00%, among which the mixed infection of bacteria and virus (25.99%) was the most common. 78 cases had pulmonary infection, the positive rate of traditional laboratory tests was 42.31% (33/78), and of mNGS in peripheral blood was 73.08% (57/78), showing a statistical difference (P = 0.000). The non-HSCT patients had a higher frequency of Klebsiella pneumonia (OR=0.777, 95% CI, 0.697-0.866, P = 0.01) and Torque teno virus (OR=0.883, 95% CI, 0.820-0.950, P = 0.031) infections than HSCT patients, while the rates of Streptococcus pneumonia (OR=12.828, 95% CI, 1.378-119.367, P = 0.016), Candida pseudosmooth (OR=1.100, 95% CI, 0.987-1.225, P = 0.016), human betaherpesvirus 6B (OR=6.345, 95% CI, 1.105-36.437, P = 0.039) and human polyomavirus 1 (OR=1.100, 95% CI, 0.987-1.225, P = 0.016) infections were lower. Leishmania could be detected by mNGS.

Conclusion

mNGS of peripheral blood can be used as a substitute test method for hematological patients with pulmonary infection, the detection rate of mixed infections by mNGS was high, and mNGS has high clinical recognition rate and sensitivity in pathogen detection, and provides a basis for guiding the anti-infective treatment in hematological diseases with symptoms such as fever.

Genetic Variants Associated with Drug Resistance of Cytomegalovirus in Hematopoietic Cell Transplantation Recipients

Cytomegalovirus (CMV) infection is a serious complication in hematopoietic cell transplantation (HCT) recipients. Drug-resistant strains make it more challenging to treat CMV infection. This study aimed to identify variants associated with CMV drug resistance in HCT recipients and assess their clinical significance. A total of 123 patients with refractory CMV DNAemia out of 2271 HCT patients at the Catholic Hematology Hospital between April 2016 and November 2021 were analyzed, which accounted for 8.6% of the 1428 patients who received pre-emptive therapy. Real-time PCR was used to monitor CMV infection. Direct sequencing was performed to identify drug-resistant variants in UL97 and UL54. Resistance variants were found in 10 (8.1%) patients, and variants of uncertain significance (VUS) were found in 48 (39.0%) patients. Patients with resistance variants had a significantly higher peak CMV viral load than those without (p = 0.015). Patients with any variants had a higher risk of severe graft-versus-host disease and lower one-year survival rates than those without (p = 0.003 and p = 0.044, respectively). Interestingly, the presence of variants reduced the rate of CMV clearance, particularly in patients who did not modify their initial antiviral regimen. However, it had no apparent impact on individuals whose antiviral regimens were changed due to refractoriness. This study highlights the importance of identifying genetic variants associated with CMV drug resistance in HCT recipients for providing appropriate antiviral treatment and predicting patient outcomes.

Oral shedding of herpesviruses and clinical outcomes in hematopoietic stem cell transplant patients

OBJECTIVES

To characterize the oral shedding of herpes viruses in patients who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT) and investigate its relationship with clinical outcomes.

MATERIALS AND METHODS

Polymerase chain reaction and enzymatic digestion were performed to identify the oral shedding of the members of the Herpesviridae family in 31 patients. The samples were collected from the oral cavity at five timestamps.

RESULTS

The presence of each herpesvirus in the oral cavity was observed in 3.2%, 12.9%, 19.3%, 32.2%, 54.8% and 93.5% patients for human herpesvirus (HHV)-6A, herpes simplex virus-1, HHV-6B, cytomegalovirus (CMV), Epstein-Barr virus (EBV) and HHV-7, respectively. Oral shedding of herpes virus was not uncommon after alloHSCT. There was a statistically significant association between the EBV and CMV oral shedding at C1 and the cumulative incidence of acute graft-versus-host disease (aGVHD). The results suggested that the presence of HSV-1 at C2 was related to a relapse. The HHV-7 oral shedding at C2 suggests a possible link between relapse, progression-free survival and overall survival of the patients.

CONCLUSIONS

Patients who developed aGVHD showed higher CMV and EBV shedding in the oral cavity at aplasia, suggesting modifications to the pattern of immune cell response and inflammatory microenvironment.

Cardiovascular morbidity following conventional therapy versus allogeneic hematopoietic stem cell transplantation after childhood, adolescent, and young adult leukemia in Finland

Allogeneic hematopoietic stem cell transplantation (aHSCT) represents a therapeutic choice for high-risk and relapsed leukemia at a young age. In this retrospective population-based study, we evaluated cardiovascular complications after aHSCT (N = 272) vs conventional therapy (N = 1098) among patients diagnosed with acute lymphoblastic or acute myeloid leukemia below 35 years between 1985 and 2004. Additionally, siblings from a prior comparison group served as population controls (N = 39 217). Childhood leukemia and aHSCT was associated with a 16-fold HR for developing arterial hypertension (HR 16.8, 95%CI 1.5-185.5) compared with conventional therapy. A 2-fold HR for any cardiovascular complication was observed after AYA leukemia and aHSCT vs conventional treatment (HR 2.7, 95% CI 1.4-5.1). After AYA leukemia and aHSCT, the HR of cardiac arrhythmia was significantly elevated vs conventional therapy (HR 14.4, 95% CI 1.5-125.2). Moreover, after aHSCT in childhood, elevated hazard ratios (HRs) were found for cardiomyopathy/ cardiac insufficiency (HR 105.0, 95% CI 10.0-1100.0), cardiac arrhythmia, and arterial hypertension (HR 20.1, 95%CI 2.5-159.7 and HR 20.0, 95%CI 4.1-97.4) compared with healthy controls. After adolescent and young adult (AYA) leukemia and aHSCT, markedly increased HRs were observed for cardiac arrhythmia (HR 29.2, 95%CI 6.6-129.2), brain vascular thrombosis/ atherosclerosis and cardiomyopathy/cardiac insufficiency (HR 23.4, 95%CI 7.1-77.4 and HR 19.2, 95%CI 1.5-245.2) compared with healthy controls. As the cumulative incidence for cardiovascular complications rose during the follow-up of childhood and AYA leukemia patients, long-term cardiovascular surveillance is warranted to optimize the quality of life after childhood and AYA leukemia following both conventional treatment and aHSCT.

New trends in the management of cytomegalovirus infection after allogeneic hematopoietic cell transplantation: a survey of the Infectious Diseases Working Pary of EBMT

The management of cytomegalovirus (CMV) infection was assessed with a survey performed in 2020 by the Infectious Diseases Working Party of European Society for Blood and Marrow Transplantation (EBMT). One-hundred-eighty of the 579 EBMT centres (31%) responded. CMV monitoring with quantitative PCR for CMV-DNAemia was used by 97% of centres while the duration of monitoring was variable according to the patient immune recovery and the ongoing immunosuppressive therapy. CMV prophylaxis for high-risk patients was used in 101 (56%) of centres: letermovir in 62 centres (61%), aciclovir/valaciclovir in 19 centres (19%), ganciclovir/valganciclovir in 17 centres (17%), foscarnet in 3 (3%). The most used trigger for pre-emptive therapy was a threshold of >10³ copies/ml or >10³ IU/ml. Ganciclovir/valganciclovir confirmed the preferred first line treatment both for pre-emptive and CMV disease therapy. CMV-cytotoxic T-cells were used mainly in the setting of relapsing/refractory CMV disease. Forty-eight centres reported CMV refractory/resistant infection due to mutated CMV strain.This survey showed that letermovir prophylaxis is adopted by more than half of centres using a prophylaxis approach for CMV infection. How letermovir prophylaxis will modify other important pillars of daily CMV management, such as frequency of CMV-DNAemia monitoring and preemptive therapy, remain a matter of investigation.

An impact of CMV and HHV-6 reactivation on the course of early period after hematopoietic stem cell transplantation in patients with hematologic malignancies

   Objective. To assess the impact of CMV and HHV-6 reactivation on the course of early post-transplant period in patients with hematologic malignancies.   Materials. Retrospective analysis of medical records of 339 patients with hematologic malignancies who received hematopoietic stem cell transplantation (HSCT) was performed, and markers of CMV and HHV-6 infections were detected (specific IgG, EIA). Blood and other materials from HSCT recipients were tested (PCR) for viral DNA in early post-transplant period (up to Day 100).

   Results. Reactivation of viral infections after HSCT was discovered in 177 patients (52,2 %): CMV-infection was detected in 23 %, HHV-6 in 17,4 %, CMV+HHV-6 in 11,6 % of HSCT recipients. CMV DNA was predominantly identified in blood, while HHV-6 DNA was more frequently discovered in GIT mucosa and bone marrow. 40 % of 99 patients with HHV-6 reactivation had concomitant CMV+HHV-6 reactivation. In this group, the clinical manifestation of infections was registered significantly more frequently. Febrile neutropenia was more frequent in HSCT recipients with CMV reactivation, sepsis and graft hypofunction were diagnosed more frequently in presence of HHV-6 and predominantly HHV-6+CMV infections. The direct correlation (using Spearman’s method) between CMV and HHV-6 reactivation and terms of leukopoiesis recovery, engraftment terms, and transplant hypofunction was revealed. An impact of herpetic infections reactivation on the graft hypofunction and late recovery of leukopoiesis was confirmed using the logistic regression; its impact on the chimerism was revealed. In 72 % of cases, the graft failure in early post-transplant period occurred in patients with herpetic infections reactivation.   Conclusion. HHV-6 and CMV reactivation in the early period after HSCT correlates with terms of leukopoiesis recovery, contributes to development of complications, and is an additional factor aggravating the course of the post-transplant period.

Hematopoietic Stem Cell Transplantation in Refractory Crohn's Disease: Should It Be Considered?

Hematopoietic stem cell transplantation (HSCT) is widely used in benign and malignant hematological diseases. During the last decade, HSCT, mainly autologous, also gained increasing attention in the treatment of refractory autoimmune diseases. Crohn's disease (CD) is an inflammatory bowel disease leading to transmural inflammation potentially affecting all parts of the luminal gastrointestinal tract. Despite improving therapeutic options, including various biologics, some patients are refractory to all lines of available conservative therapy, leading to increased morbidity and reduced quality of life. Apart from surgery, HSCT might be a reasonable treatment alternative for refractory CD patients. This review aims to describe the current role of HSCT in CD and discusses the procedure, the correct patient selection, the clinical efficacy from initial remission to following relapse rates, and complications of this treatment.

Features of cytomegalovirus infection and evaluation of cytomegalovirus-specific T cells therapy in children’s patients following allogeneic hematopoietic stem cell transplantation: A retrospective single-center study

Cytomegalovirus (CMV) infection remains a critical cause of mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT), despite improvement by pre-emptive antivirus treatment. CMV-specific cytotoxic T lymphocytes (CMV-CTL) are universally used and proven well-tolerance after allo-HSCT in adult clinical trials. However, it is not comprehensively evaluated in children’s patients. Herein, we conducted a retrospective study to determine the risk factors of CMV infection and evaluation of CMV-CTL in children patients who underwent allo-HSCT. As result, a significantly poor 5-year overall survival was found in the CMV infection group (87.3 vs. 94.6%, p=0.01). Haploidentical HSCT (haplo-HSCT) was identified as an independent risk factor for CMV infection through both univariate and multivariate analyses (p<0.001, p=0.027, respectively). Furthermore, the cumulative incidence of CMV infection was statistically higher in the haplo-HSCT group compared to the HLA-matched donor group (44.2% vs. 21.6%, p<0.001). Finally, the overall response rate of CMV-CTL was 89.7% (26/29 patients) in CMV infection after allo-HSCT. We concluded that CMV infection following allo-HSCT correlated with increased mortality in children’s patients, and haplo-HSCT was an independent risk factor for CMV infection. Adoptive CMV-CTL cell therapy was safe and effective in pediatric patients with CMV infection.

Early diagnostic value of liver stiffness measurement in hepatic sinusoidal obstruction syndrome induced by hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT)-sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease, is a clinical syndrome characterized by symptoms, such as right upper quadrant pain, jaundice, fluid retention, and hepatomegaly, and is caused by pre-treatment-related hepatotoxicity during the early stages after HSCT. Clinical diagnosis of HSCT-SOS is based on the revised Seattle or Baltimore standards. The revised standard by the European Society for Bone Marrow Transplantation in 2016 has good practicability and can be used in combination with these two standards. Eight studies have shown the value of liver stiffness measurement (LSM) in the early diagnosis of HSCT-SOS. Four studies investigated LSM specificity and sensitivity for the early diagnosis of HSCT-SOS. LSM can distinguish SOS from other post-HSCT complications, enabling a clear differential diagnosis. It has been shown that median LSM of patients with SOS is significantly higher than that of patients with other treatment-related liver complications (e.g., acute cholecystitis, cholangitis, antifungal drug-related liver injury, liver graft-versus-host disease, isolated liver biochemical changes, and fulminant Epstein Barr virus related hepatitis reactivation). Therefore, the above data confirmed the utility of LSM and strongly suggested that LSM improves the positive predictive value of the SOS diagnostic clinical score after allogeneic HSCT. Early diagnosis of SOS is beneficial in preventing severe HSCT complications.

Risk factors and incidence of cytomegalovirus viremia and disease in pediatric patients with allogeneic hematopoietic stem cell transplantation: An 8-year single-center experience in Latin America

BACKGROUND

Cytomegalovirus infection represents a significant cause of morbidity and mortality after hematopoietic stem cell transplantation. This study aimed to evaluate the incidence of viremia and disease due to cytomegalovirus and the risk factors in pediatric patients with hematopoietic stem cell transplantation in our institution.

METHODS

This was a retrospective cohort of patients under 19 years of age who underwent allogeneic hematopoietic stem cell transplantation due to any indication between 2012 and 2019. The analysis included the diagnosis of cytomegalovirus viremia or disease during post-transplant follow-up, evaluation of risk factors, and outcomes. The statistical analysis included univariate and multivariate analyses, and the cumulative incidence of cytomegalovirus viremia was determined by the Kaplan-Meier method using STATA 14 statistical software.

RESULTS

A total of 182 transplants were included. At 100 days, the cumulative incidence of cytomegalovirus viremia was 70.5%, and that of cytomegalovirus disease was 4.7%. Overall survival at 2 years was 74%, and event-free survival was 64%. The remaining demographic characteristics were not predictors of infection. There was no association between viremia and relapse or survival of the patients. Higher mortality was noted in cytomegalovirus disease.

CONCLUSIONS

During the study period, the incidence of cytomegalovirus disease was similar to that of other pediatric reports, but the incidence of viremia was higher. Pre-emptive therapy has diminished disease rates and death due to infection. Viral load cutoff points should be standardized to guide treatment and avoid myelotoxicity.

Herpesvirus Screening in Childhood Hematopoietic Transplant Reveals High Systemic Inflammation in Episodes of Multiple Viral Detection and an EBV Association with Elevated IL-1β, IL-8 and Graft-Versus-Host Disease

Infections remain a major cause of morbidity and mortality among hematopoietic stem cell transplant (HSCT) recipients. Unlike Epstein–Barr Virus (EBV) and Human Cytomegalovirus (HCMV), Human Herpesvirus (HHV) 6, HHV7 and HHV8 are not routinely monitored in many centers, especially in the pediatric population of low–medium income countries. We screened EBV, HCMV, HHV6, HHV7 and HHV8 in 412 leukocytes-plasma paired samples from 40 pediatric patients assisted in a tertiary hospital in Mexico. Thirty-two underwent allo-HSCT, whereas eight received auto-HSCT. Overall viral detection frequencies in allo- and auto-HSCT were: EBV = 43.7% and 30.0%, HCMV = 5.0% and 6.7%, HHV6 = 7.9% and 20.0% and HHV7 = 9.7% and 23.3%. HHV8 was not detected in any sample. Interestingly, HHV6 and HHV7 were more frequent in auto-HSCT, and HHV6 was observed in all episodes of multiple detection in auto-HSCT patients. We found EBV DNA in plasma samples, whereas HCMV, HHV6 and HHV7 DNA were predominantly observed in leukocytes, indicative of their expansion in cellular compartments. We also found that IL-1β, IL-2, IL-6 and IL-8 were significantly increased in episodes in which multiple viruses were simultaneously detected, and samples positive for EBV DNA and graft-versus-host disease had a further increase of IL-1β and IL-8. In conclusion, the EBV, HCMV, HHV6 and HHV7 burdens were frequently detected in allo- and auto-HSCT, and their presence associated with systemic inflammation.

Relationship between certain HLA alleles and the risk of cytomegalovirus reactivation following allogeneic hematopoietic stem cell transplantation

INTRODUCTION

Evidence is emerging to support an association between certain HLA alleles and the risk of cytomegalovirus (CMV) reactivation following allogeneic HSCT (allo-HSCT). The primary aim of this study was to identify HLA alleles associated with resistance or susceptibility to CMV reactivation.

METHODS

We studied 586 adults who underwent allo-HSCT for high-risk hematological malignancies. High resolution HLA typing data was available for recipient and donor. HLA Class I and II alleles observed at a frequency of > 5% in our population, were included in the analysis. A CMV viremia level of more than 200 IU/ml on weekly monitoring was considered to be indicative of CMV reactivation.

RESULTS

The median follow-up time in surviving patients was 21 months (range 4-74 months). The cumulative incidence of CMV reactivation at 6 months in the entire cohort was 55% (95% CI 50.8%-59.2%). Mismatched donor, increasing recipient age, occurrence of AGVHD and recipient CMV seropositivity were associated with increased risk of CMV reactivation. HLA B*07:02 (HR 0.59, 95% CI 0.40-0.83) was associated with decreased risk of CMV reactivation. Patients who developed CMV reactivation had a lower incidence of relapse, higher transplant related mortality (TRM) and lower overall survival (OS) compared to those without CMV reactivation. There was an adverse correlation of OS and TRM with increasing numbers of CMV reactivations.

CONCLUSION

We observed that HLA B*07:02 was associated with decreased risk of CMV reactivation. CMV reactivation was associated with lower relapse post-transplant, but this did not translate into a survival benefit due to higher transplant related mortality. This article is protected by copyright. All rights reserved.

Features of Epstein-Barr Virus and Cytomegalovirus Reactivation in Acute Leukemia Patients After Haplo-HCT With Myeloablative ATG-Containing Conditioning Regimen

Background

Haploidentical donor hematopoietic cell transplantation (haplo-HCT) has become a preferred option for patients without HLA-matched donors, but it increases the risk of viral reactivations. Epstein-Barr virus (EBV) and cytomegalovirus (CMV) are common viruses post-HCT, but limited data have been reported in the setting of haplo-HCT.

Methods

We conducted a retrospective study enrolling acute leukemia patients who received haplo-HCT with myeloablative conditioning regimen employing ATG in our center from July 2014 to July 2017. All the patients enrolled were EBV-IgM and EBV-DNA negative but EBV-IgG positive, and so were their donors. The same went for CMV as well.

Results

In total, 602 patients were recruited consisting of 331 with acute myeloid leukemia (AML) and 271 with acute lymphoblastic leukemia (ALL). One-year cumulative incidences of EBV (22.9% ± 2.4% vs. 27.4% ± 2.8%, P = 0.169) and CMV (24.7% ± 2.4% vs. 29.4% ± 2.8%, P = 0.190) reactivation were comparable between AML and ALL. EBV and CMV were independent risk factors for each other. In the AML group, male recipients [HR = 1.275, 95% CI (1.001-1.624), P = 0.049] and acute graft-versus-host disease [HR = 1.592, 95% CI (1.001-2.533), P = 0.049] were independent risk factors for EBV reactivation and CMV reactivation, respectively. CMV rather than EBV reactivation was related to a trend of worsened treatment-related mortality (TRM) (15.6% ± 0.1% vs. 10.2% ± 0.0%, P = 0.067) and progression-free survival (PFS) (60.6% ± 4.1% vs. 70.3% ± 2.3%, P = 0.073), while significant impacts were revealed only in the subgroup analysis. CMV reactivation resulted in a remarkable inferior 2-year overall survival (OS) (64.2% ± 5.7% vs. 77.6% ± 3.2%, P = 0.038) and PFS (55.0% ± 5.9% vs. 71.9% ± 3.4%, P = 0.042) in ALL patients. On the other hand, in the EBV+/CMV- subgroup, relapse was lower in ALL patients (8.2% ± 0.2% vs. 32.4% ± 0.8%, P = 0.010) compared with AML patients, which led to a superior 2-year OS (82.0% ± 6.2% vs. 60.3% ± 8.8%, P = 0.016) and PFS (74.5% ± 7.0% vs. 57.5% ± 8.4%, P = 0.036).

Conclusion

We concluded that EBV and CMV reactivations were frequent in acute leukemia patients after haplo-HCT, with possibly distinctive risk factors from HLA-matched HCT. There could be a potential interaction between EBV and CMV, but impacts on transplant outcomes remained complex.

Immunoprofiling reveals cell subsets associated with the trajectory of cytomegalovirus reactivation post stem cell transplantation

Human cytomegalovirus reactivation is a major opportunistic infection after allogeneic haematopoietic stem cell transplantation and has a complex relationship with post-transplant immune reconstitution. Here, we use mass cytometry to define patterns of innate and adaptive immune cell reconstitution at key phases of human cytomegalovirus reactivation in the first 100 days post haematopoietic stem cell transplantation. Human cytomegalovirus reactivation is associated with the development of activated, memory T-cell profiles, with faster effector-memory CD4⁺ T-cell recovery in patients with low-level versus high-level human cytomegalovirus DNAemia. Mucosal-associated invariant T cell levels at the initial detection of human cytomegalovirus DNAemia are significantly lower in patients who subsequently develop high-level versus low-level human cytomegalovirus reactivation. Our data describe distinct immune signatures that emerged with human cytomegalovirus reactivation after haematopoietic stem cell transplantation, and highlight Mucosal-associated invariant T cell levels at the first detection of reactivation as a marker that may be useful to anticipate the magnitude of human cytomegalovirus DNAemia.

Human cytomegalovirus is a major cause of morbidity and mortality in transplant patients and multiple immune cells types are critical during infection and reactivation. Here the authors assess the immune cell compartments of haematopoietic stem cell recipients in the early period post transplantation and identify key features of effector memory CD4⁺ T cells and mucosal associated invariant T cells in this context.

Association Between Cytomegalovirus and Epstein-Barr Virus Co-Reactivation and Hematopoietic Stem Cell Transplantation

The co-reactivation of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) in patients undergoing hematopoietic stem cell transplantation (HSCT) has been found. Research has shown that the reactivation of CMV or EBV is closely related to poor HSCT outcomes. In this study, we describe the clinical characteristics of HSCT patients with co-reactivation of CMV and EBV. We retrospectively reviewed the medical records of 327 patients who underwent HSCT at the Peking University People’s Hospital Institute of Hematology. Co-reactivation of CMV and EBV was observed in a total of 75 patients (22.9%) who also had a higher incidence of hemorrhagic cystitis (P=0.000). HSCT patients with CMV and co-reactivation of CMV and EBV had a significantly lower 1-year overall survival (OS; P=0.050). Further, COX regression analysis showed that viral infection was a risk factor for 1-year OS (HR, 12.625 for co-reactivation vs. no reactivation, p=0.021, and HR 13.580 for CMV reactivation vs. no reactivation, P=0.013). In conclusion, the patients with CMV reactivation had poorer outcome after HSCT regardless of EBV reactivation.

Current management of CMV infection in cancer patients (solid tumors). Epidemiology and therapeutic strategies

Little evidence is available regarding the incidence of CMV disease in patients with solid cancers. Latest data show that approximately 50 % of these patients with CMV PCR positivity developed clinically relevant CMV-viremia, and would require specific therapy. In the clinical arena, CMV reactivation is an important differential diagnosis in the infectological work up of these patients, but guidelines of management on this subject are not yet available. CMV reactivation should be considered during differential diagnosis for patients with a severe decline in lymphocyte counts when receiving chemoradiotherapy or immunochemotherapy with lymphocyte-depleting or blocking agents. Monitoring of CMV reactivation followed by the implementation of preemptive strategies or the establishment of early antiviral treatment improves the prognosis and reduces the morbidity and mortality of these patients.

Exposure-Response Analyses of Letermovir Following Oral and Intravenous Administration in Allogeneic Hematopoietic Cell Transplantation Recipients

The cytomegalovirus (CMV) viral terminase inhibitor letermovir is approved for prophylaxis of CMV infection and disease in adult CMV-seropositive allogeneic hematopoietic stem cell transplantation recipients. In a phase III trial (NCT02137772), letermovir significantly reduced clinically significant CMV infection (CS-CMVi) rate vs. placebo through Week 24 (primary end point) and Week 14 (secondary end point) post transplantation. Here, exposure-response relationships were investigated using efficacy and selected safety end points from the phase III trial to inform the proposed clinical dose. Post hoc exposure estimates were derived from a population pharmacokinetic model. No significant exposure dependencies were found for CS-CMVi through Week 24 or Week 14 among letermovir-treated participants. Evaluated covariates had no impact on exposure-efficacy relationships and letermovir plasma exposure did not affect time of CS-CMVi onset. There was no dependence between adverse event incidence and letermovir exposure. These results support current dosing recommendations in several countries and regions, including the United States and European Union.

[The correlation between post-allo-HSCT CMV infection and the difference affinity of donor HLA-type recognition of CMV antigen peptide in children]

Objective: To explore the correlation between the affinity while donor's HLA type recognizing different cytomegalovirus (CMV) antigen peptide and the occurrence of CMV infection after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children. Methods: To investigate the relationship between CMV reactivation, CMV infection or CMV related tissue/organ diseases and the different HLA-type recognition antigen peptide of the donors, we retrospectively analyzed the clinical data of 146 children with CMV infection for 6 months since from the time they underwent transplantation in Wuhan Children's Hospital. Results: Among 146 patients, the HLA type of 82 (56.16%) cases had high affinity with PP65 alone, and 34 cases of CMV infection occurred after transplantation (41.46%) . None of 5 cases that had a high affinity with IE-1 alone got CMV infection. None of 2 cases with no clear high-affinity peptide had CMV infection. Three of 5 cases that had a high affinity with PP65 and PP50 had CMV infection. Thirteen of 52 cases that had a high affinity with PP65 and IE-1 had CMV infection (25.00%) . HLA with exclusive PP50 high affinity was not encountered. Donors with a high-affinity HLA locus associated with IE-1 showed a lower incidence of CMV infection after HSCT compared to those carrying only the PP65 high-affinity allele (22.81% vs 41.46%, P=0.029) . Conclusion: HLA type with PP65 and IE-1 high-affinity covers approximately 99.8% of the donors. Stem cells generated from HLA donors with high affinity with the CMV antigen peptide IE-1 can reduce the risk of post-transplantation CMV-activated infection in children.

Epstein-Barr virus and cytomegalovirus reactivation after allogeneic hematopoietic cell transplantation in patients with non-Hodgkin lymphoma: the prevalence and impacts on outcomes : EBV and CMV reactivation post allo-HCT in NHL

Epstein–Barr virus (EBV) and cytomegalovirus (CMV) reactivations are common complications after allogeneic hematopoietic cell transplantation (allo-HCT), but data focusing on non–Hodgkin lymphoma (NHL) are limited. We retrospectively analyzed the prevalence of EBV and CMV reactivation post-allo-HCT and the impacts on transplant outcomes in 160 NHL patients. The 1-year incidences of EBV and CMV reactivation were 22.58% and 25.55%, respectively. Independent impactors for EBV reactivation were more than 6 lines of chemotherapy (P = 0.030), use of rituximab (P = 0.004), and neutrophil recovery within 30 days post-HCT (P = 0.022). For T-cell lymphoblastic lymphoma patients, the International Prognostic Index (IPI) (P = 0.015) and chronic GVHD (P = 0.001) increased the risk of CMV reactivation. CMV reactivation was independently related to a lower risk of relapse (P = 0.027) but higher transplant-related mortality (TRM) (P = 0.038). Although viral reactivation had no significant impact on overall survival (OS) in the whole cohort, it led to an inferior 2-year OS (67.6% versus 92.5%, P = 0.005) and TRM (20.1% versus 4.7%, P = 0.020) in recipients surviving for more than 180 days. We concluded that EBV and CMV reactivation post-allotransplant still deserved concern particularly in NHL patients with high-risk factors, since it is generally related to a deteriorated prognosis. Large-scale studies are warranted to validate our findings.

Parental limited English proficiency in pediatric stem cell transplantation: Clinical impact and health care utilization

BACKGROUND

Limited English proficiency (LEP) is associated with adverse clinical outcomes. The clinical impact of LEP in hematopoietic stem cell transplant (HSCT) has not been studied. The objectives of this study were to compare HSCT outcomes and health care utilization of Hispanic pediatric patients with and without parental LEP.

METHODS

We conducted a retrospective review of Hispanic/Latino pediatric patients receiving HSCT at a single institution. Families were identified as LEP or English proficient (EP) based on clinicians' notes, social work documentation, or the signature of a Spanish interpreter on treatment consents.

RESULTS

A total of 83 Hispanic/Latino patients were identified with 53 (65.1%) having parental LEP. More patients in the LEP group had a documented financial burden at pretransplant psychosocial evaluation (72.2% vs. 41.4%, p = .009). LEP patients were more likely to have health insurance coverage through government-sponsored Medicaid (76.9% vs. 27.6%, p < .001). LEP patients were hospitalized on average 13 days longer than EP patients, and LEP patients were more likely to have pretransplant cytomegalovirus (CMV) reactivity (67.3%) than EP patients (p = .001). Overall survival was lower in LEP than EP, but was not statistically significant (p = .193). Multivariable Cox modeling suggested a potentially higher risk of death in LEP versus EP (hazard ratio = 1.56, 95% CI: 0.38, 6.23).

CONCLUSIONS

Parental LEP in HSCT is associated with prolonged hospitalization and pretransplant CMV reactivity. These factors are associated with posttransplant complications and death. Our results suggest parental LEP is a risk factor for poor HSCT outcomes. Further study is warranted in a larger cohort.

Cytomegalovirus (CMV) management in allogeneic hematopoietic cell transplantation: Pre-transplant predictors of survival, reactivation, and spontaneous clearance

BACKGROUND

Cytomegalovirus (CMV) reactivation is a frequent complication after allogeneic hematopoietic cell transplant (alloHCT).

METHOD

We analyzed 159 alloHCT recipients with 4409 quantitative CMV viral loads to determine pre-transplant predictors of CMV reactivation, clinically significant CMV infection (cs-CMVi, defined as CMV viral load >1000 IU/mL), CMV disease, kinetics of spontaneous clearance of CMV, and survival using a standardized pre-emptive therapy approach to identify at-risk groups to target prevention strategies.

RESULTS

Cs-CMVi was most common in D-/R+ unrelated donor transplants (URD). Spontaneous CMV clearance occurred in 26% of patients who reached a viral load of 56-137 IU/mL, 6% at 138-250 IU/mL and in one patient >250 IU/mL. Median time between the first CMV reactivation (>56 IU/mL) and a viral load >250 IU/mL was 13 days, whereas the time from the first viral load >250 IU/mL to reach a vial load >1000 IU/mL was 4 days. Cs-CMVi was associated with a significant increase in non-relapse mortality (NRM) on multivariate analysis.

CONCLUSIONS

Overall, this study indicates that D-/R+ URD recipients are at high-risk for cs-CMVi- and CMV-related mortality, and are potential candidates for targeted CMV prophylaxis. Spontaneous clearance of CMV beyond a viral load of 250 IU/mL is uncommon, suggesting that this could be used as an appropriate threshold to initiate pre-emptive therapy.

Cytomegalovirus DNAemia and risk of mortality in allogeneic hematopoietic stem cell transplantation: Analysis from the Spanish Hematopoietic Transplantation and Cell Therapy Group

The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research.

Clinical outcomes of allogeneic hematopoietic stem cell transplant recipients developing Cytomegalovirus DNAemia prior to engraftment

There is limited information on the impact of CMV DNAemia episodes developing prior to engraftment (pre-CMV DNAemia) on clinical outcomes following allogeneic hematopoietic stem cell transplantation (allo-HSCT). This issue was addressed in the current retrospective multicenter study including 878 patients. All participant centers used preemptive antiviral therapy strategies for prevention of CMV disease. CMV DNA load in blood was monitored by real-time PCR assays. A total of 144 patients (cumulative incidence 16.5%, 95% CI, 14%-19%) had an episode of pre-CMV DNAemia at a median of 10 days after allo-HSCT. Patients who developed pre-CMV DNAemia had a significantly higher (P = < 0.001) probability of recurrent episodes (50%) than those who experienced post-CMV DNAemia (32.9%); Nevertheless, the incidence of CMV disease was comparable (P = 0.52). Cumulative incidences of overall mortality (OM) and non-relapse mortality (NRM) at 1-year after allo-HSCT were 32% (95% CI, 29-35%) and 23% (95% CI 20-26%), respectively. The risk of OM and NRM in adjusted models appeared comparable in patients developing a single episode of CMV DNAemia, regardless of whether it occurred before or after engraftment, in patients with pre- and post-engraftment CMV DNAemia episodes or in those without CMV DNAemia.

Alternative donor peripheral blood stem cell transplantation for the treatment of high-risk refractory and/or relapsed childhood acute leukemia: a randomized trial

Background

The high-risk refractory and/or relapsed (R/R) childhood acute leukemia prognosis is poor, and allogeneic stem cell transplantation (allo-HSCT) is the most prudent treatment modality. However, there are limited matched sibling donors (MSDs), and alternative donors (ADs) are the main source for allo-HSCT. Thus, we evaluated the clinical efficacy of AD peripheral allo-HSCT for treating high-risk R/R childhood acute leukemia.

Methods

We assessed 111 children who underwent allo-HSCT at the Affiliated Cancer Hospital of Zhengzhou University between October 2006 and July 2019. The patients were divided in the MSD and AD groups, and their clinical characteristics, complications, and survival rates were compared.

Results

The cumulative incidences of Epstein–Barr virus and cytomegalovirus infections were significantly higher in the AD than in the MSD group (P < 0.001); however, the recurrence and mortality rates were significantly higher in the MSD than in the AD group (P < 0.05). Furthermore, the 5-year disease-free (DFS) (65.2% vs. 43.3%, P = 0.033) and overall survival (OS) rates (71.6% vs. 53.8%, P = 0.053) were significantly higher in the AD than in the MSD group. In the AD group, the grade II–IV acute graft-versus-host disease (aGVHD), donor-recipient ABO compatibility, conditioning regimen, and CMV infection affected the 5-year OS. The grade II–IV aGVHD also affected the 5-year DFS; however, only the donor-recipient ABO compatibility affected the 5-year DFS. The donor MSD (HR: 2.035, 95% confidence interval [CI] 1.057–3.920, P = 0.034) and the grade II–IV aGVHD (HR: 2.914, 95% CI 1.261–6.736, P = 0.012) affected the 5-year DFS of childhood acute leukemia after allo-HSCT, and the grade II–IV aGVHD (HR: 3.016, 95% CI 1.217–7.473, P = 0.017) affected the 5-year OS. Moreover, the donor source (HR: 2.836, 95% CI 1.179–6.823, P = 0.020) and grade II–IV aGVHD (HR: 3.731, 95% CI 1.332–10.454, P = 0.012) were independent predictors of the 5-year DFS, while the latter (HR: 3.524, 95% CI 1.310–10.988, P = 0.030) was an independent predictor of the 5-year OS.

Conclusions

AD-PBSCT was effective for high-risk R/R childhood leukemia and may have better clinical outcomes than MSD-PBSCT; thus, it can be used as first-line treatment for high-risk R/R childhood leukemia.

Features of Cytomegalovirus DNAemia Blips in Allogeneic Hematopoietic Stem Cell Transplant Recipients: Implications for Optimization of Preemptive Antiviral Therapy Strategies

Cytomegalovirus (CMV) DNAemia occurs frequently in allogeneic hematopoietic stem cell transplant recipients (allo-HSCT). There is limited information about the incidence, features, and clinical impact of CMV DNAemia blips (episodes defined by an isolated positive PCR result) in this setting. In this retrospective study, 225 consecutive adult patients undergoing any modality of allo-HSCT at our center between May 2012 and July 2019 were included. Plasma CMV DNA load was monitored using a highly sensitive real-time PCR assay. In all, 187 of 225 patients had CMV DNAemia through day 365 after allo-HSCT (total number of episodes, n = 379). Eighty-three of the 187 patients had 1 or more blips (n = 104). Blips occurred as a first episode of CMV DNAemia as opposed to prolonged CMV DNAemia (≥2 consecutive positive PCR results) in 47 patients; in 20 of these patients, blips represented the only documented episode throughout the study period, and in 27 patients, blips preceded a prolonged CMV DNAemia episode. In the remaining 36 patients, blips developed as recurrences. Blips presenting as initial episodes occurred more frequently (P < .001) in patients receiving an allograft from a CMV-seropositive donor. The cumulative incidence of recurrent CMV DNAemia following initial blips, self-resolving prolonged CMV DNAemia episodes, or CMV DNAemia episodes treated preemptively with antivirals was not significantly different (P = .34). Receiver operating characteristic curve analysis indicated that a CMV DNA load cutoff of 48 IU/mL yielded the highest combined sensitivity (66%) and specificity (70.2%) for predicting a prolonged CMV DNAemia episode. The practical implications of our data in the optimization of preemptive antiviral therapy strategies are discussed.