Diffuse alveolar hemorrhage (DAH) is a life-threatening complication of hematopoietic cellular therapy (HCT). This study aimed to evaluate the effect of DAH treatments on outcomes using data from consecutive HCT patients clinically diagnosed with DAH from 3 institutions between January 2018-August 2022. Endpoints included sustained complete response (sCR) defined as bleeding cessation without recurrent bleeding, and non-relapse mortality (NRM). Forty children developed DAH at a median of 56.5 days post-HCT (range 1-760). Thirty-five (88%) had at least one concurrent endothelial disorder, including transplant-associated thrombotic microangiopathy (n=30), sinusoidal obstructive syndrome (n=19), or acute graft versus host disease (n=10). Fifty percent had a concurrent pulmonary infection at the time of DAH. Common treatments included steroids (n=17, 25% sCR), inhaled tranexamic acid (INH TXA,n=26, 48% sCR), and inhaled recombinant activated factor VII (INH fVIIa, n=10, 73% sCR). NRM was 56% 100 days after first pulmonary bleed and 70% at 1 year. Steroid treatment was associated with increased risk of NRM (HR 2.25 95% CI 1.07-4.71, p=0.03), while treatment with INH TXA (HR 0.43, 95% CI 0.19- 0.96, p=0.04) and INH fVIIa (HR 0.22, 95% CI 0.07-0.62, p=0.005) were associated with decreased risk of NRM. Prospective studies are warranted to validate these findings.

With limited data comparing hematopoietic cell transplant outcomes between myeloablative total body irradiation (TBI) containing and non-TBI regimens in children with de novo acute myeloid leukemia, the aim of this study was to compare transplant-outcomes between these regimens. Cox regression models were used to compare transplant-outcomes after TBI and non-TBI regimens in 624 children transplanted between 2008 and 2016. Thirty two percent (n=199) received TBI regimens whereas 68% (n=425) received non-TBI regimens. Five-year non-relapse mortality was higher with TBI regimens (22% vs. 11%, p<0.0001) but relapse was lower (23% vs. 37%, p<0.0001) compared to non-TBI regimens. Consequently, overall (62% vs. 60%, p=1.00) and leukemia-free survival (55% vs. 52%, p=0.42) did not differ between treatment groups. Grade II-IV acute GVHD was higher with TBI regimens (56% vs. 27%, p<0.0001) but not chronic GVHD. The 3-year incidence of gonadal or growth hormone deficiency was higher with TBI regimens (24% vs. 8%, p<0.001) but there were no differences in late pulmonary, cardiac or renal impairment. In the absence of a survival advantage, the choice of TBI or non-TBI regimen merits careful consideration with the data favoring non-TBI regimens to limit the burden of morbidity associated with endocrine dysfunction.

Adult hematopoietic stem cell transplantation (HSCT) recipients are at a high risk of adverse outcomes after COVID-19. Although children have had better outcomes after COVID-19 compared to adults, data on risk factors and outcomes of COVID-19 among pediatric HSCT recipients are lacking. We describe outcomes of HSCT recipients who were ≤21 years of age at COVID-19 diagnosis and were reported to the Center for International Blood and Marrow Transplant Research between March 27, 2020, and May 7, 2021. The primary outcome was overall survival after COVID-19 diagnosis. We determined risk factors of COVID-19 as a secondary outcome in a subset of allogeneic HSCT recipients. A total of 167 pediatric HSCT recipients (135 allogeneic; 32 autologous HSCT recipients) were included. Median time from HSCT to COVID-19 was 15 months (interquartile range [IQR] 7-45) for allogeneic HSCT recipients and 16 months (IQR 6-59) for autologous HSCT recipients. Median follow-up from COVID-19 diagnosis was 53 days (range 1-270) and 37 days (1-179) for allogeneic and autologous HSCT recipients, respectively. Although COVID-19 was mild in 87% (n = 146/167), 10% (n = 16/167) of patients required supplemental oxygen or mechanical ventilation. The 45-day overall survival was 95% (95% confidence interval [CI], 90-99) and 90% (74-99) for allogeneic and autologous HSCT recipients, respectively. Cox regression analysis showed that patients with a hematopoietic cell transplant comorbidity index (HCT-CI) score of 1-2 were more likely to be diagnosed with COVID-19 (hazard ratio 1.95; 95% CI, 1.03-3.69, P = .042) compared to those with an HCT-CI of 0. Pediatric and early adolescent and young adult HSCT recipients with pre-HSCT comorbidities were more likely to be diagnosed with COVID-19. Overall mortality, albeit higher than the reported general population estimates, was lower when compared with previously published data focusing on adult HSCT recipients.

Community respiratory viral infections (CRVIs) are associated with pulmonary function impairment, alloimmune lung syndromes and inferior survival in human leucocyte antigen (HLA)-matched allogeneic haematopoietic stem cell transplant (HCT) recipients. Although the incidence of viral infections in HLA-haploidentical HCT recipients who receive post-transplant cyclophosphamide (PTCy)-based graft-versus-host disease (GVHD) prophylaxis is reportedly increased, there are insufficient data describing the incidence of CRVIs and the impact of donor source and PTCy on transplant outcomes. Analysing patients receiving their first HCT between 2012 and 2017 for acute myeloid leukaemia, acute lymphoblastic leukaemia and myelodysplastic syndromes, we describe comparative outcomes between matched sibling transplants receiving either calcineurin-based GVHD prophylaxis (SibCNI, N = 1605) or PTCy (SibCy, N = 403), and related haploidentical transplants receiving PTCy (HaploCy, N = 757). The incidence of CRVIs was higher for patients receiving PTCy, regardless of donor type. Patients in the HaploCy cohort who developed a CRVI by day +180 had both a higher risk of treatment-related mortality [hazard ratio (HR) 2⋅14, 99% confidence interval (CI) 1⋅13-4⋅07; P = 0⋅002] and inferior 2-year overall survival (HR 1⋅65, 99% CI 1⋅11-2⋅43; P = 0⋅001) compared to SibCNI with no CRVI. This finding justifies further research into long-term antiviral immune recovery, as well as development of preventive and treatment strategies to improve long-term outcomes in such patients.

Transplant-associated thrombotic microangiopathy (TA-TMA) is a severe complication of hematopoietic stem cell transplantation (HSCT). A single-center prospective screening study has shown that the incidence of TA-TMA is much higher than prior retrospective studies that did not systematically screen. These data have not been replicated in a multicenter study. Our objective was to determine the incidence and risk factors for TA-TMA and compare outcomes of pediatric HSCT patients with and without TA-TMA. Patients were prospectively screened for TA-TMA at participating centers using a simple to implement and inexpensive strategy from the start of the preparative regimen through day +100. TA-TMA was diagnosed if ≥4 of 7 laboratory/clinical markers diagnostic for TA-TMA were present concurrently or if tissue histology showed TA-TMA. A total of 614 patients (359 males; 58%) received prospective TA-TMA screening at 13 pediatric centers. TA-TMA was diagnosed in 98 patients (16%) at a median of 22 days (interquartile range, 14-44) posttransplant. Patients with TA-TMA had significantly increased bloodstream infections (38% [37/98] vs 21% [107/51], P ≤ .001), mean total hospitalization days (68; 95% confidence interval [CI], 63-74 vs 43; 95% CI, 41-45; P ≤ .001), and number of days spent in the intensive care unit (10.1; 95% CI, 6.4-14; vs 1.6; 95% CI, 1.1-2.2; P ≤ .001) in the first 100 days after HSCT compared with patients without TA-TMA. Overall survival was significantly higher in patients without TA-TMA (93%; 490/516) compared with patients with TA-TMA (78%; 76/98) (P ≤ .001). These data support the need for systematic screening for TA-TMA and demonstrate the feasibility and efficacy of an easy to implement strategy to do so.

The use of post-transplantation cyclophosphamide (PTCy) for graft-versus-host disease (GVHD) prophylaxis in recipients of haploidentical and fully matched transplantations is on the increase. Published studies have reported an increased incidence of cytomegalovirus (CMV) infection with the use of PTCy. Limited data exist on the incidence and outcomes of infection with non-CMV herpesviruses (NCHV) in this setting. The aim of this study was to evaluate the cumulative incidence of NCHV infections and the association of NCHV infections with transplantation-specific outcomes in recipients of haploidentical transplantation with PTCy (HaploCy), matched sibling donor transplantation with PTCy (SibCy), and matched sibling donor transplantation with calcineurin inhibitor-based prophylaxis (SibCNI). We hypothesized that, like CMV infection, HaploCy recipients of also will have a higher risk of NCHV infections. Using the Center for International Blood and Marrow Transplantation Research database, we analyzed 2765 patients (HaploCy, n = 757; SibCNI, n = 1605; SibCy, n = 403) who had undergone their first hematopoietic stem cell transplantation (HCT) between 2012 and 2017 for acute myelogenous leukemia, acute lymphoblastic leukemia, or myelodysplastic syndrome. The cumulative incidence of NCHV at 6 months post-NCT was 13.9% (99% confidence interval], 10.8% to 17.3%) in the HaploCy group, 10.7% (99% CI, 7.1% to 15%) in the SibCy group, and 5.7% (99% CI, 4.3% to 7.3%) in the Sib CNI group (P < .001). This was due primarily to a higher frequency of human herpesvirus 6 viremia reported in patients receiving PTCy. The incidence of Epstein-Barr viremia was low in all groups, and no cases of post-transplantation lymphoproliferative disorder were seen in either PTCy group. The incidence of NCHV organ disease was low in all 3 cohorts. The development of NCHV infection was associated with increased treatment-related mortality, particularly in the HaploCy group. There was no association with the development of GVHD, relapse, or disease-free survival. Patients in PTCy cohorts who did not develop NCHV infection had lower rates of cGVHD. This study demonstrates that the use of PTCy is associated with an increased risk of NCHV infection. The development of NCHV infection was associated with increased nonrelapse mortality, especially in the HaploCy group. Prospective trials should consider viral surveillance strategies in conjunction with assessment of immune reconstitution for a better understanding of the clinical relevance of viral reactivation in different HCT settings.

We analyzed CIBMTR data to evaluate the incidence of non-relapse mortality (NRM) and association with overall survival (OS) for bacterial blood stream infections (BSIs) occurring within 100 days of alloHCT in 2 different phases: pre-/peri-engraftment (BSI very early phase, BSI-VEP) and BSI post-engraftment (BSI occurring between 2 weeks after engraftment and day 100, late early phase, BSI-LEP). Of the 7128 alloHCT patients, 2656 (37%) had ≥1 BSI by day 100. BSI-VEP, BSI-LEP, and BSI-Both constituted 56% (n = 1492), 31% (n = 824), and 13% (n = 340) of total BSI, respectively. Starting in 2009, we observed a gradual decline in BSI incidence through 2012 (61-48%). Patients with BSI-VEP were more likely to receive a myeloablative conditioning (MAC) regimen with total body irradiation (TBI). NRM was significantly higher in patients with any BSI (RR 1.82 95% CI 1.63-2.04 for BSI-VEP, RR 2.46, 95% CI 2.05-2.96 for BSI-LEP, and RR 2.29, 95% CI 1.87-2.81 for BSI-Both) compared with those without BSI. OS was significantly lower in patients with any BSI compared with patients without BSI (RR 1.36, 95% CI 1.26-1.47 for BSI-VEP; RR 1.83, 95% CI 1.58-2.12 for BSI-LEP: RR 1.66, 95% CI 1.43-1.94 for BSI-Both). BSIs within day 100 after alloHCT are common and remain a risk factor for mortality.

Follow-up is integral for hematopoietic cell transplantation (HCT) care to ensure surveillance and intervention for complications. We characterized the incidence of and predictors for being lost to follow-up. Two-year survivors of first allogeneic HCT (10,367 adults and 3865 children) or autologous HCT (7291 adults and 467 children) for malignant/nonmalignant disorders between 2002 and 2013 reported to the Center for International Blood and Marrow Transplant Research were selected. The cumulative incidence of being lost to follow-up (defined as having missed 2 consecutive follow-up reporting periods) was calculated. Marginal Cox models (adjusted for center effect) were fit to evaluate predictors. The 10-year cumulative incidence of being lost to follow-up was 13% (95% confidence interval [CI], 12% to 14%) in adult allogeneic HCT survivors, 15% (95% CI, 14% to 16%) in adult autologous HCT survivors, 25% (95% CI, 24% to 27%) in pediatric allogeneic HCT survivors, and 24% (95% CI, 20% to 29%) in pediatric autologous HCT survivors. Factors associated with being lost to follow-up include younger age, nonmalignant disease, public/no insurance (reference: private), residence farther from the tranplantation center, and being unmarried in adult allogeneic HCT survivors; older age and testicular/germ cell tumor (reference: non-Hodgkin lymphoma) in adult autologous HCT survivors; older age, public/no insurance (reference: private), and nonmalignant disease in pediatric allogeneic HCT survivors; and older age in pediatric autologous HCT survivors. Follow-up focusing on minimizing attrition in high-risk groups is needed to ensure surveillance for late effects.

Alternative graft sources (umbilical cord blood [UCB], matched unrelated donors [MUD], or mismatched unrelated donors [MMUD]) enable patients without a matched sibling donor to receive potentially curative hematopoietic cell transplantation (HCT). Retrospective studies demonstrate comparable outcomes among different graft sources. However, the risk and types of infections have not been compared among graft sources. Such information may influence the choice of a particular graft source. We compared the incidence of bacterial, viral, and fungal infections in 1781 adults with acute leukemia who received alternative donor HCT (UCB, n= 568; MUD, n = 930; MMUD, n = 283) between 2008 and 2011. The incidences of bacterial infection at 1 year were 72%, 59%, and 65% (P < .0001) for UCB, MUD, and MMUD, respectively. Incidences of viral infection at 1 year were 68%, 45%, and 53% (P < .0001) for UCB, MUD, and MMUD, respectively. In multivariable analysis, bacterial, fungal, and viral infections were more common after either UCB or MMUD than after MUD (P < .0001). Bacterial and viral but not fungal infections were more common after UCB than MMUD (P = .0009 and <.0001, respectively). The presence of viral infection was not associated with an increased mortality. Overall survival (OS) was comparable among UCB and MMUD patients with Karnofsky performance status (KPS) ≥ 90% but was inferior for UCB for patients with KPS < 90%. Bacterial and fungal infections were associated with poorer OS. Future strategies focusing on infection prevention and treatment are indicated to improve HCT outcomes.

Background

We examined the impact of vancomycin-resistant Enterococcus (VRE) bloodstream infection (BSI) on outcomes of allogeneic hematopoietic cell transplantation (HCT) utilizing the Center for International Blood and Marrow Transplant Research database.

Methods

Adult and pediatric patients (N = 7128) who underwent first HCT for acute leukemia or myelodysplastic syndrome from 2008 through 2012 were analyzed as 3 groups-VRE BSI, non-VRE BSI, without BSI-according to BSI status at 100 days (D100) after allogeneic HCT. Multivariable models examined the effect of VRE BSI for overall survival (OS) and nonrelapse mortality (NRM) at 1 year.

Results

Of 7128 patients, 258 (3.2%) had VRE BSI, 2398 (33.6%) had non-VRE BSI, and 4472 (63%) had no BSI. The median time to VRE BSI and non-VRE BSI were D11 and D15, respectively. Compared with non-VRE BSI patients, VRE BSI patients were older, had advanced-stage acute leukemia, and received umbilical cord blood (UCB) allografts. In multivariable models, VRE BSI was associated with lower OS (relative risk [RR], 2.9;(99% confidence interval [CI], 2.2-3.7) and increased NRM (RR, 4.7; 99% CI, 3.6-6.2) (P < .0001) for both. Other predictors for worse OS and increased NRM were non-VRE BSI, older age, advanced disease stage, UCB allograft, - mismatch, comorbidity index ≥3, and cytomegalovirus seropositivity (P < .001 for all variables).

Conclusions

VRE BSI is associated with lowest OS and highest NRM compared with patients without BSI or non-VRE BSI. Novel interventions that address the pathophysiology of VRE BSI have the potential of improving survival after HCT.