Increased Epstein‒Barr virus reactivation following prophylaxis for cytomegalovirus infection after haploidentical haematopoietic stem cell transplantation.

Letermovir (LTV) prophylaxis is effective in reducing the incidence of clinically significant cytomegalovirus (CMV) infection (cs CMVi) after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Since our centre began administering LTV prophylaxis in June 2022, we have observed a certain increase in the incidence of Epstein-Barr virus (EBV) reactivation after haploidentical HSCT. We retrospectively analysed 230 consecutive patients who underwent haploidentical HSCT with rabbit anti-thymocyte globulin (ATG) from October 2022 to June 2023. The LTV group included 133 patients who received LTV prophylaxis, and the control group included 97 patients who did not receive LTV prophylaxis. At 1 year after HSCT, EBV reactivation was observed in 36 patients (27%) in the LTV group and 13 patients (13%) in the control group (p = 0.012). All patients with EBV reactivation had EBV-DNAemia, and one patient in each group developed EBV-associated posttransplantation lymphoproliferative disorder (PTLD). The proportion of patients with low EBV-DNA loads (> 5 × 102 to < 1 × 104 copies/mL) was greater in the LTV group than in the control group (23% vs. 10%, p = 0.01). The proportion of patients with CMV reactivation was lower in the LTV group than in the control group (35% vs. 56%, p = 0.002). There was no significant difference between the groups in terms of neutrophil and platelet count recovery, the cumulative incidence of acute/chronic graft-versus-host disease, overall survival, cumulative relapse rate or nonrelapse mortality. Our results show that the increased incidence of EBV reactivation may be associated with LTV prophylaxis for CMV after haploidentical HSCT.

Umbilical cord blood stem cells as third-party adjuvant infusions in human leukocyte antigen antibody-positive patients undergoing haploidentical hematopoietic stem cell transplantation.

Introduction: Graft failure (GF) or poor graft function (PGF) remain critical obstacles in haploidentical hematopoietic stem cell transplantation (haplo-HSCT), especially in recipients with HLA antibodies. Here, we performed a retrospective cohort study to investigate the efficacy and safety of the use of unrelated umbilical cord blood stem cells (UCBs) as a third-party adjuvant infusion in patients with HLA-antibodies undergoing haplo-HSCT. Methods: A total of 90 patients were divided into three groups: 17 patients in Group A (with positive HLA antibodies and who received UCB infusion), 36 patients in Group B (with positive HLA antibodies without UCB infusion), and 37 patients in Group C (without HLA antibody or UCB infusion). Results: The median age of patients included in Groups A, B, and C was 43 (IQR, 27 - 49.5), 33 (IQR, 20 - 48.75), and 30 (IQR, 18 - 46.5) years, respectively. All but one patient in Group B achieved granulocyte recovery within 28 days after transplantation. The median time to granulocyte engraftment were all 12 days for patients in Groups A, B, and C, respectively. All the patients in Group A achieved 100% donor chimerism without UCB engraftment. There were no significant differences in granulocyte or platelet engraftment time between the three groups. There were 1, 5, and 0 patients in Groups A, B, and C, respectively, who developed PGF. The cumulative incidence rates for any grade of acute graft-versus-host disease (aGVHD) were comparable among the three groups. Patients in Group B presented a greater incidence of cGVHD than did those in Group A (P = 0.002) and Group C (P = 0.006). Patients in Group A presented more limited and milder cGVHD than those in Group C (P < 0.0001). The 1-year relapse-free survival (RFS) was 70.6% (95% CI, 0.47 - 0.87), 55.6% (95% CI, 0.40 - 0.70), and 77.9% (95% CI, 0.63 - 0.89) in Groups A, B, and C, respectively. Discussion: Our results indicated that patients who were positive for HLA antibodies were at a greater risk of developing GF/PGF. Co-infusion with UCBs was safe and improved engraftment, cGVHD, and improved the 1-year RFS to some extent.

Improved Outcomes in Myelofibrosis after Allogeneic Stem-Cell Transplantation in the Era of Ruxolitinib Pretreatment and Intensified Conditioning Regimen-Single-Center Analysis.

(1) Background: Allogeneic hematopoietic stem-cell transplantation (allo-HSCT) is the only treatment with the potential for cure in patients with myelofibrosis (MF). However, the risk of graft rejection, which is particularly high in MF, and the risk of significant non-relapse mortality must be considered. (2) Methods: In this retrospective, single-center study, we compared allo-HSCT outcomes in 36 adult patients with MF transplanted at two-time intervals (2001-2015 versus 2016-2021). (3) Results: The estimated median overall survival was 48.9 months (95%CI 0.00-98.2) in the cohort transplanted before 2016 and not reached in the more recent years (p = 0.04) due to markedly lower non-relapse mortality (p = 0.02). The 3-year relapse incidence was low in both cohorts (11.1% and 12.5%, p > 0.99). When comparing only subgroups within the more recent cohort based on the presence or absence of total body irradiation (TBI) or the use of sequential regimens, OS and PFS were comparable. (4) Conclusion: Pretreatment with ruxolitinib, intensified conditioning, and the preferential use of haploidentical related instead of mismatched unrelated donors for patients lacking an HLA-identical donor are most likely responsible for the improved outcome after allo-HCT in MF in recent years.

High-dose chemotherapy as initial salvage chemotherapy in patients with relapsed or refractory testicular cancer: a systematic review and meta-analysis.

Background: The role of high-dose chemotherapy followed by autologous hematopoietic cell transplantation in the management of patients with relapsed/refractory germ-cell tumors has not been established in prospective studies. Our aim was to estimate the benefits and harm of this treatment in men with relapsed/refractory germ-cell tumors. Methods: Electronic databases, conference proceedings, and trial registers until April 30, 2023, were searched. Randomized and non-randomized prospective controlled trials were included. Risk of bias assessments were performed using either RoB2 or ROBINS-I tools. The certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach. Time-to-event data were analyzed using the hazard ratio. The primary outcome was overall survival, and a meta-analysis was not conducted to assess it because non-randomized trials were judged to have a critical risk of bias. Categorical data were analyzed using a risk ratio. All results are presented with the corresponding 95% confidence interval. Results: Four out of 3,824 records met the inclusion criteria, and three out of four were used to assess primary and secondary outcomes. Based on the IT94 study (N = 263 participants), single high-dose chemotherapy followed by autologous hematopoietic cell transplantation may have little to no effect on overall survival [hazard ratio (HR) 0.98, 95%CI 0.68 to 1.42; p = 0.916]. Non-randomized trials (N = 43 participants) showed contrasting results, which may be explained by the number of cycles of high-dose chemotherapy administered in each study. Regarding secondary outcomes, information was only provided for event-free survival, response rate, and acute toxicities. Conclusions: Based on prospective data, there is insufficient evidence to support or refute the proposal that high-dose chemotherapy with autologous hematopoietic cell transplantation improves survival in men with relapsed/refractory germ-cell tumors. If this treatment is considered essential, the choice should be made by experienced clinicians at high-volume cancer centers.

The impact of delayed versus early administration of granulocyte colony-stimulating factor following autologous hematopoietic stem cell transplantation on transplantation outcome.

Objectives: Granulocyte colony-stimulating factor (G-CSF) is routinely administered after autologous hematopoietic stem cell transplantation (auto-HSCT) to decrease the duration of neutropenia and diminish the incidence of febrile neutropenia. Nevertheless, the most advantageous timeframe for administering G-CSF in the transplantation setting remains elusive. Material and Methods: We conducted a cross-sectional study of 200 patients diagnosed with hematological malignancies who underwent auto-HSCT between July 2017 and January 2022. Patients were divided into two groups of 100 individuals based on the timing of G-CSF administration after auto-HSCT. In the first group, G-CSF was administered on post-transplantation day +1, while in the second group, G-CSF was administered on post-transplantation day +5. Patient demographics and clinical outcomes, including time to neutrophil engraftment, time to platelet engraftment, length of hospital stay, duration of fever, and incidence of bacterial and fungal bloodstream infections, were compared between the two groups. Results: We identified a significantly shorter platelet engraftment time in the day +5 group than in the day +1 group (P<0.001), though the groups were similar regarding neutrophil engraftment time. The total number of G-CSF injections differed significantly according to the administration schedule. The number of red blood cells and length of hospital stay was greater in the day +1 group (all P<0.001). The incidence of bacterial and fungal bloodstream infections and duration of fever did not differ between the groups. Conclusion: Delayed administration of G-CSF on day +5 is as effective as early administration and can positively influence platelet engraftment, transfusion support, and hospitalization time.

Successful management with urgent haploidentical-peripheral blood stem cell transplantation for a patient with severe aplastic anaemia who developed disseminated fungal infection following immunosuppressive therapy.

Urgent haploidentical haematopoietic cell transplantation may be considered in cases of severe aplastic anaemia (SAA) without a human leukocyte antigen-matched donor and suffering from severe infection. However, deciding on allogeneic transplantation in the setting of active systemic infection is challenging due to poor outcomes. This report presents a case of disseminated Magnusiomyces capitatus infection in a 5-year-old male who underwent immunosuppressive therapy for hepatitis-associated SAA. To address the critical situation, granulocyte transfusion was promptly administered from the patient's mother, followed by unmanipulated haploidentical peripheral blood stem cell transplantation from the patient's father with posttransplant cyclophosphamide, ultimately resulting in successful rescue.

Novel method for assessing sinusoidal obstruction syndrome using four-dimensional computed tomography.

Introduction: To diagnose sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD), transabdominal ultrasonography is usually used to detect hemodynamic changes, but we tried to detect the changes using four-dimensional computed tomography (4D-CT). A 42-year-old Japanese woman was diagnosed with late-onset SOS/VOD with transabdominal ultrasonography and was also assessed using 4D-CT. Method We analyzed the portal vein (PV) contrast effect every 1.5 seconds and plotted the values of the contrast effect. With this graph, we analyzed three hemodynamic parameters. Result: We found that these parameters correlated with the patient's status and indicated stasis due to sinusoid constriction. Conclusion: 4D-CT may become a helpful tool to diagnose and follow up with SOS/VOD.

Feasibility of intravenous vitamin C supplementation in allogeneic hematopoietic cell transplant recipients.

Introduction: Intravenous vitamin C was administered following hematopoietic stem cell transplant to mitigate nonrelapse mortality (NRM) in a Phase II clinical trial. Methods: Patients with advanced hematologic malignancies received IV vitamin C, 50 mg/kg/day, in three divided doses on days 1-14 after HSCT, followed by 500 mg bid oral until 6 months. Results: All patients enrolled (55) were deficient in vitamin C at day 0 and had restoration to normal levels. Vitamin C recipients had a trend for lower nonrelapse mortality (NRM, 11% vs. 25%, p-value = 0.07) compared with propensity score-matched historical controls. A similar trend toward improved survival was observed (82% vs. 62% p = 0.06), with no attributable grade 3 and 4 toxicities to vitamin C. Conclusion: In patients undergoing allogeneic HSCT, repletion of vitamin C is feasible and may reduce NRM and improve overall survival. Randomized trials in large uniform cohorts of patients are needed to confirm the utility of this easily available and inexpensive therapy.

Comparative outcomes of various transplantation platforms, highlighting haploidentical transplants with post-transplantation cyclophosphamide for adult T-cell leukaemia/lymphoma.

This study retrospectively compared outcomes of various allogeneic haematopoietic cell transplantation (allo-HCT) platforms in patients with adult T-cell leukaemia/lymphoma. Platforms included human leukocyte antigen (HLA)-haploidentical-related donors using post-transplant cyclophosphamide (PTCY), HLA-matched related donors (MRD), HLA-matched unrelated donors (MUD) and cord blood transplantation (CBT). Patients who underwent their first allo-HCT between 2016 and 2021 were included. Outcomes analysed were overall survival (OS), relapse and non-relapse mortality (NRM). Seven hundred patients were included (PTCY, n = 121; MRD, n = 91; MUD, n = 160; CBT, n = 328). With a median follow-up of 794 days for survivors, 2-year OS was 48.1% (PTCY), 48.8% (MRD), 48.4% (MUD) and 34.6% (CBT); the respective 2-year cumulative incidence of relapse was 37.1%, 47.5%, 33.9% and 45.1% and that of NRM was 24.2%, 19.8%, 24.7% and 27.3%. PTCY was associated with delayed platelet engraftment relative to MRD and MUD. There was no increase in the incidence of severe acute or chronic graft-versus-host disease. In the PTCY group, poor performance status was a significant predictor of inferior OS, and infused CD34+ cell numbers of less than 5 × 106/kg were associated with delayed neutrophil and platelet engraftment. These results suggest that allo-HCT with PTCY is a safe and effective platform for patients with adult T-cell leukaemia/lymphoma.

Maintenance Therapy Post-Stem Cell Transplantation for Patients with T-Cell Lymphomas.

PURPOSE OF REVIEW: Given the poor outcomes for peripheral T-cell lymphomas (PTCL), stem cell transplant (SCT) remains an important therapeutic approach. Post-SCT relapse is common and maintenance therapy post-SCT is increasingly being utilized. Here we review the use of post-SCT maintenance therapy for PTCL patients. RECENT FINDINGS: Maintenance therapy is increasingly utilized to decrease post-SCT relapse and improve outcomes in PTCL. Ongoing and completed post-SCT maintenance trials utilizing agents such as romidepsin, brentuximab vedotin, duvelisib, and pembrolizumab have shown efficacy in decreasing relapse. Further, additional agents with efficacy in PTCL have emerged that may inform future maintenance approaches. Maintenance therapy is a promising approach to maintain response after SCT in PTCL. While several trials are ongoing to evaluate maintenance therapy in PTCL, current data suggests this may be an effective method to decrease post-SCT relapse.

Multicenter randomized phase III study of high-dose therapy with autologous stem cell transplantation versus observation for patients with newly diagnosed peripheral T-cell lymphoma who achieved complete metabolic response after induction therapy (JCOG2210, TRANSFER study).

Patients with peripheral T-cell lymphoma demonstrated a poor prognosis after obtaining a complete response with induction treatment compared to those with B-cell lymphoma. Once it relapsed, curative treatment is frequently limited to invasive treatments with significant treatment-related mortality, including allogeneic stem cell transplantation. The limitations of these treatment choices indicate the necessity for developing optimal consolidation therapies to prevent relapse. This multicenter randomized phase III trial aims to confirm the superiority of the high-dose therapy with autologous stem cell transplantation over observation alone in terms of progression-free survival for patients with newly diagnosed peripheral T-cell lymphoma who achieved complete metabolic response after induction therapy. A total of 140 patients from 52 hospitals will be enrolled in Japan over 5.5 years. This trial is registered in the Japan Registry of Clinical Trials as jRCTs031240169 (https://jrct.niph.go.jp/latest-detail/jRCTs031240169).

First-Line Use of Daratumumab in Patients with Multiple Myeloma Shows Delayed Neutrophil and Platelet Engraftment after Autologous Stem Cell Transplantation: Results from a Real-Life Single-Center Study.

BACKGROUND: This real-life study aimed to investigate the possible impact of D-VTd induction therapy on hematopoietic engraftment after autologous stem cell transplantation (auto-SCT). METHODS: Sixty consecutive NDMM patients received four cycles of induction therapy with D-VTd. The conditioning regimen consisted of melphalan 200 mg/m2. These patients were compared with a historical control group of 80 patients who received four cycles of VTd as induction therapy. RESULTS: The median days to reach neutrophil and platelet engraftment significantly differed between patients treated with D-VTd (11 and 13 days, respectively) and VTd (10 and 12 days). Univariate Cox analyses show that patients treated with D-VTd had a hazard ratio of neutrophil engraftment that was 42% significantly lower than those in the VTd arm (HR: 0.58, p = 0.002), and a multivariate model confirmed this result. Patients treated with D-VTd developed FN more frequently. Univariate and multivariate logistic regressions revealed an association between D-VTd and FN. Delayed engraftment did not correlate with more extended hospitalization. No patients died in the first six months after transplantation. CONCLUSIONS: Our real-life study showed that a four-drug induction therapy containing DARA does not impact transplant safety outcomes.

Gender-Specific Prognostic Impact of Treosulfan Levels in High-Dose Chemotherapy for Multiple Myeloma.

INTRODUCTION: The growing body of evidence around sexual and gender dimorphism in medicine, particularly in oncology, has highlighted differences in treatment response, outcomes, and side effects between males and females. Differences in drug metabolism, distribution, and elimination, influenced by factors like body composition and enzyme expression, contribute to these variations. METHODS: We retrospectively analyzed data of 112 multiple myeloma (MM) patients treated with first-line high-dose chemotherapy (HDCT) with treosulfan and melphalan (TreoMel) followed by autologous stem cell transplantation (ASCT) at a single academic center between January 2020 and August 2022. We assessed response rate, progression-free survival (PFS), overall survival (OS), and toxicities in relation to gender and treosulfan exposure. RESULTS: Our analysis revealed significant gender-specific differences in treosulfan exposure. Females had higher peak levels (343.8 vs. 309.0 mg/L, p = 0.0011) and area under the curve (AUC) (869.9 vs. 830.5 mg*h/L, p = 0.0427) compared to males. Higher treosulfan exposure was associated with increased mortality in females but not in males. Females with treosulfan AUC > 900 mg*h/L had significantly shorter overall survival, while PFS was unaffected by treosulfan exposure. CONCLUSION: Our study demonstrates that female patients undergoing TreoMel HDCT have higher treosulfan exposure than males and that females with higher levels are at increased risk for toxicity and adverse outcomes. These data suggest that higher treosulfan doses do not confer a benefit in terms of better outcomes for females. Therefore, exploring lower treosulfan doses for female MM patients undergoing TreoMel HDCT may be warranted to mitigate toxicity and improve outcomes.

Superior Survival After Unrelated Allogeneic Stem Cell Transplantation With Low-Dose ATG Compared to Low-Dose TBI in Myeloablative Fludarabine/Busulfan-Based Regimen for MDS on Behalf of the Adult MDS Working Group of the JSTCT.

The fludarabine/intravenous busulfan 12.8 mg/kg (FB4) regimen is an effective conditioning regimen in allogeneic hematopoietic stem cell transplantation for myelodysplastic syndrome (MDS); however, limited data is available on the prognostic impact of FB4 with low-dose anti-thymoglobulin (ATG ≤ 5 mg/kg) or low-dose total body irradiation (TBI ≤ 4 Gy). Therefore, we retrospectively evaluated the outcomes in 280 adults with de novo MDS who underwent their first transplantation from an unrelated donor between 2009 and 2018. Median age was 61 yr (range, 16 to 70 yr). In the FB4 alone (FB4), FB4 plus ATG (FB4-ATG), and FB4 plus TBI (FB4-TBI) groups, 3-yr overall survival (OS) rates were 39.9%, 64.8%, and 43.7%; 3-yr nonrelapse mortality (NRM) were 32.1%, 22.1%, and 27.1%; and 3-yr relapse incidences were 34.7%, 21.2%, and 28.9%, respectively. The multivariate analyses showed that FB4-ATG group significantly correlated with better OS (hazard Ratio [HR], 0.51; 95% confidence interval [CI], 0.27 to 0.95; P = .032) than FB4 group. FB4-ATG group tended to correlate with lower NRM (HR, 0.36; 95% CI, 0.13 to 1.06; P = .063) than FB4 group. In comparison with FB4-TBI group, FB4-ATG group showed better OS (HR 0.52, 95% CI 0.27 to 0.99, P = .049) and NRM (HR 0.034, 95% CI 0.11 to 0.92, P = .034). No significant differences were observed in OS and NRM between the FB4-TBI and FB4 groups. The present study demonstrated that the FB4 plus low-dose ATG regimen improved OS and NRM, but FB4 plus low-dose TBI regimen had no clear benefit over FB4 alone, in MDS patients who used unrelated donors.

Comparative analysis of single versus tandem autologous stem cell transplantation in patients with multiple myeloma in Korea: the KMM2102 study.

Tandem autologous stem cell transplantation can improve the prognosis of patients with multiple myeloma. However, the precise role of tandem transplantation remains debatable. We evaluated the clinical benefits of tandem transplantation retrospectively. Of the 655 included patients, 117 underwent tandem transplantation; the remaining were assigned to the control group. After a single transplantation, the tandem group achieved a complete remission (CR) rate of 24.8%, which increased to 46.2% after a second transplantation. The tandem group had a significantly longer median PFS than the control group in patients with International Staging System (ISS) III and high-risk cytogenetics (23.1 vs. 14.7 months, p = 0.007 for ISS III; 21.7 vs. 13.2 months, p = 0.042 for high-risk cytogenetics). The tandem group exhibited significantly superior PFS to the control group (20.3 vs. 12.6 months, p = 0.003) among patients who failed to achieve CR after a single transplantation. Tandem transplantation was associated with significantly improved PFS after adjusting for maintenance therapy in patients with ISS III, those with high-risk cytogenetics, and those who did not achieve CR after a single transplantation. Following propensity score matching, the tandem group exhibited significantly longer PFS than the control group (30.3 vs. 13.5 months, p = 0.028). Tandem transplantation should be considered in high-risk patients.

Pre-Transplant Dual-Energy X-ray Absorptiometry (DXA)-Derived Body Composition Measures as Predictors of Treatment Outcomes and Early Post-Transplant Complications in Patients with Multiple Myeloma (MM) Treated with Autologous Hematopoietic Stem Cell Transplantation (AutoHSCT).

Background/Objectives: Changes in muscle mass and bone density are common in multiple myeloma (MM) patients. Dual-energy X-ray absorptiometry (DXA) offers precise, non-invasive insights into a patient's physical condition before autologous stem cell transplantation (autoHSCT). This study examines how pre-transplant body composition impacts treatment outcomes and early complications in MM patients undergoing autoHSCT. Methods: This study is a single-center, retrospective analysis of patients with MM who were treated with first or second autoHSCT and underwent DXA pre-transplant between 11 August 2019 and 12 June 2024. Results: We conducted a study of pre-transplant body composition in 127 patients with MM. Among them, 108 (85%) qualified for first autoHSCT, while 19 (15%) qualified for a second. The median age of the patients was 64 years (range 50-73). In the Cox proportional hazards regression conducted in the group of women, Total Body %Fat was a statistically significant predictor for progression-free survival (PFS) (HR = 0.07, 95% CI = 0.01,0.6, p = 0.0157). In the Mann-Whitney U test conducted on males, Lean Mass/Height2 and Appen. Lean Height2 were statistically significant predictors of early infections after autoHSCT (Z = 1.98, p = 0.0473 and Z = 2.32, p = 0.0204, respectively). In males, Fat Mass/Height2 was a significant predictor of non-infectious toxicity related to treatment (Z = -1.98, p = 0.0476). Conclusions: In women, higher levels of adipose tissue initially appear to exert a protective effect; however, this benefit diminishes over time, with greater fat mass eventually correlating with an increased risk of disease progression. In men, muscle mass has been identified as a significant predictor of early infection risk post-autoHSCT. Furthermore, our findings indicate that an increased amount of adipose tissue in men is statistically associated with a higher risk of non-infectious treatment-related toxicity. These conclusions highlight the critical need for further investigation into the role of body composition.

Early Fever in Allogeneic Stem Cell Transplantation: Are Presepsin and YKL-40 Valuable Diagnostic Tools?

Background: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a lifesaving treatment but carries a high infection risk. Diagnosing infections remains challenging due to the limited accuracy of standard biomarkers. Methods: This single-center study aimed to evaluate presepsin (PSP) and YKL-40 as infection biomarkers in febrile patients during the allo-HSCT pre-engraftment phase. Biomarker levels were prospectively measured in 61 febrile episodes from 54 allo-HSCT patients at admission, representing baseline levels, and then at Day 1, 3, 5, and 7 following fever onset. The diagnostic value was compared to that of procalcitonin (PCT). Results: PSP showed fair diagnostic value on Day 1 (AUC 0.656; 95% CI: 0.510-0.802) and Day 3 (AUC 0.698; 95% CI: 0.559-0.837). YKL-40 did not provide any significant diagnostic value across measured time points. PCT outperformed PSP and YKL-40, particularly on Day 3 (AUC 0.712; 95% CI: 0.572-0.852). When combining biomarkers, the best model for predicting infection used PSP > 3.144 ng/mL and PCT > 0.28 µg/L on Day 3, resulting in R2 of about 31% (p < 0.001). Conclusions: Neither test showed sufficient discriminative power for early infection to recommend their use as individual diagnostic tools in clinical practice.

Influence of the Bone Marrow Microenvironment on Hematopoietic Stem Cell Behavior Post-Allogeneic Transplantation: Development of Clonal Hematopoiesis and Telomere Dynamics.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potential cure for myelodysplastic neoplasms (MDSs) and other hematologic malignancies. This study investigates post-transplantation genetic evolution and telomere dynamics in hematopoietic cells, with a focus on clonal hematopoiesis (CH). We conducted a longitudinal analysis of 21 MDS patients who underwent allo-HSCT between September 2009 and February 2015. Genetic profiles of hematopoietic cells from both recipients and donors were compared at equivalent pre- and post-transplantation time points. Targeted sequencing identified CH-associated mutations, and real-time quantitative PCR measured telomere length. Furthermore, we compared CH incidence between recipients and age-matched controls from the GENIE cohort from routine health checkups. Post-allo-HSCT, 38% of recipients developed somatic mutations not detected before transplantation, indicating de novo CH originating from donor cells. Compared to age-matched healthy controls, recipients showed a significantly higher incidence of CH, suggesting increased susceptibility to genetic changes post-transplant. Telomere length analysis also revealed accelerated shortening in transplanted cells, highlighting the heightened stress and proliferation demands in the new microenvironment. Our findings reveal a notable incidence of donor-derived CH in allo-HSCT recipients, alongside significant telomere attrition. This suggests the potential influence of the marrow microenvironment on genetic and molecular changes in hematopoietic cells.

Global landscape of vancomycin-resistant enterococci in hematopoietic stem-cell transplantation patients: a systematic review and meta-analysis.

BACKGROUND: One of the main risks of infection after hematopoietic stem cell transplantation (HSCT) is infection by gram-positive bacteria, including vancomycin-resistant enterococci (VRE). Based on the format of a global review and meta-analysis study, this study aims to investigate the incidence of VRE bloodstream infection (BSI) after HSCT in colonized individuals. METHODS: The keywords of the systematic search included vancomycin-resistant enterococci and HSCT. These words were searched in Google Scholar, PubMed/Medline, Scopus, and Web of Science databases from January 1, 2000, to March 1, 2024. Studies that reported the prevalence of vancomycin-resistant enterococci in patients undergoing HSCT were included. The random effects model was used for the meta-analyses. Investigations were conducted according to PRISMA guidelines, and the protocol was registered in PROSPERO: CRD42024543491. RESULTS: Out of 1100 screened papers, 28 were eligible. The random effects model was established to analyze the incidence of VRE BSI after HSCT. The pooled prevalence of co-infection for Allo-HSCT recipients was 3.023 (95% CI, Z-value = -3.5, p-value < 0.0001), and this value for Auto-HSCT recipients was 11.89 (95% CI, Z-value = -2.923, p-value < 0.001). These results showed that the rate of BSI due to vancomycin-resistant enterococcus in Auto-HSCT recipients is higher than Allo-HSCT. CONCLUSIONS: The prevalence of vancomycin-resistant enterococci in Auto-HSCT recipients is higher than that of Allo-HSCT, possibly due to colonization of the intestines of these people with vancomycin-resistant enterococci before transplantation. VRE Colonization before transplantation increases the likelihood of post-transplant VRE BSI and other bacterial infections, including Gram-negative. The strains should be analyzed by sequencing before and after HSCT for a more detailed investigation.