Hematopoietic Stem Cell Transplant Admission Research Articles

Preadmission Penicillin Allergy Evaluation Before Hematopoietic Stem Cell Transplantation Optimizes Febrile Neutropenia Treatment and Inpatient Resource Utilization

Febrile neutropenia is a common complication of conditioning chemotherapy for hematopoietic stem cell transplant (HSCT), but a major barrier for optimal treatment of febrile neutropenia is historical penicillin allergies. Our group recently published a development of a clinical pipeline for delabeling penicillin allergies in adult patients planned to undergo hematopoietic stem cell transplant (HSCT). In this retrospective cohort study, we followed patients to evaluate their outcomes during inpatient admission for HSCT. We hypothesized that, among patients planned for HSCT with a self-reported penicillin allergy, completing penicillin allergy testing (amoxicillin ingestion challenge with or without concomitant penicillin skin testing) prior to HSCT admission would be associated with differences in inpatient treatment for febrile neutropenia (including antibiotic selection and timing of antibiotic administration) and improved inpatient resource utilization (including nursing and inpatient physician consults). We identified patients with a self-reported penicillin allergy who answered a penicillin allergy questionnaire and were subsequently admitted to our institution for HSCT. We divided the cohort into 2 groups: patients whose penicillin allergy was evaluated prior to admission (EPTA) and patients whose penicillin allergy was not evaluated prior to admission (NEPTA). We then performed comparison between the 2 groups for general clinical outcomes of HSCT admission (duration of admission, need for ICU transfer, readmission rate, etc.), febrile neutropenia treatment, and inpatient resource utilization. Statistics were calculated using the non-parametric two-tailed Fisher exact test for categorical outcomes and the non-parametric two-tailed Mann-Whitney U test for numerical outcomes RESULTS: Within our cohort, 35 patients completed penicillin allergy testing prior to HSCT admission (EPTA) and 44 patients did not (NEPTA). Demographics were similar between these groups, and there was no significant difference in the rate of febrile neutropenia during HSCT admission (EPTA 64% vs NEPTA 66%, p=1.00). EPTA patients were significantly more likely to receive standard first-line antibiotics (cefepime or ceftazidime) for febrile neutropenia (EPTA 95% vs NEPTA 65%, p=0.015) and time between febrile neutropenia onset and antibiotic administration was shorter (EPTA mean 66 mins vs NEPTA mean 121 mins, p=0.0058). No patients in the EPTA group experienced an immediate hypersensitivity reaction (hives, anaphylaxis, etc.) or severe cutaneous adverse reaction (SCAR) during HSCT admission. EPTA patients were also significantly less likely to require 1:1 nursing for antibiotic test doses, challenges, and desensitizations (EPTA 0% vs NEPTA 49%, p<0.0001); less likely to require inpatient allergy consult (EPTA 0% vs NEPTA 12%, p=0.031); and less likely to require inpatient antimicrobial stewardship consult (EPTA 0% vs NEPTA 13%, p=0.013) during their HSCT admission. In summary, patients who completed penicillin allergy testing prior to HSCT admission were more likely to receive first-line antibiotics and received antibiotics more rapidly for treatment of febrile neutropenia. Furthermore, patients who completed penicillin allergy testing prior to HSCT admission were less likely to require 1:1 nursing, inpatient allergy consults, and inpatient antimicrobial stewardship consults during HSCT admission.

IMPROVE-BMT: A Pilot Randomized Controlled Trial of Prehabilitation Exercise for Adult Hematopoietic Stem Cell Transplant Recipients.

Background: There is limited evidence on the effects of aerobic and resistance training exercise interventions to improve physical function and patient-reported outcomes prior to autologous and allogeneic hematopoietic stem cell transplant (HSCT). IMPROVE-BMT was a single-site, pilot randomized controlled trial investigating the feasibility, acceptability, and safety of a pragmatic resistance training exercise program prior to HSCT compared to usual HSCT care. Secondary aims included differences in physical function between the exercise group (EX) and usual care control group (UC). Methods: Outcome measurements were assessed: prior to HSCT, on/around day of HSCT admission, +30 days post-HSCT, and +100 days post-HSCT. The exercise intervention was a home-based exercise program that incorporated resistance-band and bodyweight exercises. Results: Acceptability among participants was 83%; exercise adherence averaged at 92%; and there were zero exercise-related adverse or serious adverse events. The average pre-transplant exercise phase was 6.28 weeks (2.71-18.29 weeks). EX (n = 36) demonstrated larger increases in the six-minute walk test distance, short physical performance battery scores, and 30-s chair stands compared to UC (n = 38) and demonstrated significant within-group improvements for the six-minute walk test, the short physical performance battery, the 30-s chair stands, and the timed up-and-go test. Conclusions: IMPROVE-BMT demonstrates that pragmatic exercise is highly feasible for HSCT recipients and can potentially lead to enhanced recovery that may not be achievable in non-exercisers.

Pharmacotherapy for the Prevention of Depression and Behavioral Side Effects in Hematopoietic Stem Cell Transplantation Patients

Depression and decreased quality of life (QoL) develop in approximately 30% of nondepressed hematopoietic stem cell transplantation (HSCT) recipients early after transplantation. To potentially prevent this complication, we conducted a prospective randomized trial to assess whether prophylaxis of nondepressed HSCT patients with the antidepressant sertraline (SER) in addition to supportive psychotherapy starting at admission for transplantation decreases the risk of depression and improves QoL. The primary objective of the study was to evaluate whether there was an added benefit of SER versus placebo along with routine supportive psychotherapy on the development of depression in patients receiving HSCT. A secondary objective was to analyze the impact on patient-reported QoL and survival. The study was conducted at a single-site academic medical center. We randomized 123 nondepressed HSCT recipients (1:1) in a phase III double-blind study to receive SER starting at a dose of 50 mg/day, with possible dose escalations to 200 mg per day, or placebo beginning on admission for HSCT and continuing for 12 weeks. Supportive psychotherapy was provided for both groups. Depression (Beck Depression Inventory II [BDI-II]) and QoL (Functional Assessment of Cancer Therapy-Bone Marrow Transplantation [FACT-BMT]) were assessed prior to HSCT and then weekly to week 12 post-HSCT. A multivariable linear mixed-effects model was used to estimate the mean change in BDI-II scores as a function of elapsed time since baseline, treatment assignment, and their interaction. The same process was used to assess treatment effects on all QoL scores from the FACT-BMT assessment. A Kaplan-Meier curve was used to estimate the probability of survival for each group following initiation of treatment. A follow-up Cox proportional hazards model was used to estimate the mortality rate in the 2 groups. Our results do not indicate a benefit of SER in either a diminished risk of depression or improved QoL or survival outcomes. Based on our findings, we can only recommend early evaluation of HSCT recipients for depression, with antidepressant use reserved for patients with evidence of clinical depression, unless additional randomized trials can confirm the effects of early antidepressant therapy on mood and QoL in this vulnerable group. Future research in this area would be improved by systematic monitoring of medication adherence, identification of the optimal dose of SER (or other antidepressant), and inclusion of psychotherapy outcomes when relevant, the absence of which are limitations of this study.

Quality of Life, Physical Functioning, and Psychological Distress of Older Adults Undergoing Hematopoietic Stem Cell Transplantation

With advances in therapies for hematologic cancers, older adults increasingly undergo hematopoietic stem cell transplantation (HSCT). Older adults may potentially experience an exaggerated burden of toxicity from HSCT. Studies examining the quality of life (QOL), physical functioning, and psychological symptom trajectory for older adults undergoing HSCT are limited. Our primary aim was to describe the trajectory of QOL, physical functioning, and psychological distress of older adults undergoing HSCT. Secondarily, we aimed to compare the trajectory of QOL, physical functioning, and psychological distress of older and younger adults undergoing HSCT and to evaluate factors associated with QOL trajectory in older adults undergoing HSCT. We conducted secondary analyses of two prospective studies conducted at Massachusetts General Hospital. From 2011 to 2016, we enrolled 250 adults undergoing allogeneic or autologous HSCT. Older age was defined as age ≥65 years. We collected patient-reported outcomes (PROs) within 72 hours of admission for HSCT, at hematologic nadir (2 weeks), and at 6 months after HSCT. To assess QOL, physical functioning, and psychological symptoms, we used the Functional Assessment of Cancer Therapy (FACT)–Bone Marrow Transplant, FACT-Trial Outcome Index, and Patient Health Questionnaire–9, respectively. We used the post-traumatic stress disorder (PTSD) Checklist–Civilian Version to assess PTSD symptoms. We fit linear mixed effects models to characterize trajectories of changes in PROs across timepoints and to evaluate baseline factors associated with QOL trajectories in older adults. Overall 30.4% (76/250) of our cohort was 65 years or older. All older adults undergoing allogeneic HSCT received a reduced intensity conditioning regimen. At 2 weeks after HSCT, older patients experienced a decline in QOL (Δ = −16.6, P < .001), physical functioning (Δ = −15.4, P < .001) and an increase in depression symptoms (Δ = 3.8, P < .001). At 6 months after HSCT, QOL (Δ = 1.4, P = .7), physical functioning (Δ = 1.7, P = .5), and depression symptoms (Δ = 0.4, P = .6) recovered to baseline values. At 6 months after HSCT, the proportion of older patients with PTSD symptoms increased from 5.3% (4/76) at baseline to 13.2% (10/76). There was no significant difference in slopes or trajectories of PROs between older and younger patients. In older adults, baseline psychological distress was associated with significantly worse QOL trajectory (Δ= −21.6, P ≤ .001). Older adults experienced a sharp decline in QOL and physical functioning and an increase in depression symptoms within 2 weeks of HSCT hospitalization. Baseline psychological distress was associated with a pronounced worsening in post-HSCT QOL trajectory. These findings underscore the need for supportive care interventions to improve the experience of older adults undergoing HSCT.

Clinical and Economic Outcomes in Patients with Transfusion-Dependent β-Thalassemia and Patients with Sickle Cell Disease with Recurrent Vaso-Occlusive Crises Receiving Hematopoietic Stem Cell Transplants in the United States

Background: Transfusion-dependent β-thalassemia (TDT) and sickle cell disease (SCD) are inherited blood disorders caused by mutations in the β-globin gene, resulting in abnormal, reduced, or absent expression of hemoglobin. TDT is characterized by ineffective red blood cell production that leads to chronic anemia, need for regular red blood cell transfusions (RBCTs), and organ complications. SCD is characterized by sickle-shaped red blood cells that cause vaso-occlusive crises (VOCs), hemolysis, and end-organ damage. Hematopoietic stem cell transplant (HSCT) is currently the only curative option for patients with TDT and patients with SCD. There is limited research on the frequency and outcomes of HSCT in these two patient populations. This study describes the economic and clinical outcomes for a combined population of patients with TDT and patients with SCD with recurrent VOCs who received HSCTs in the United States. Methods: This retrospective cohort study used administrative claims from the MerativeTM Commercial, Medicare, and Multi-State Medicaid Databases to identify patients with ≥1 inpatient or ≥2 outpatient claims for β-thalassemia or SCD between March 1, 2010, and March 1, 2019. Eligible patients with TDT were required to have ≥8 discrete RBCTs in any 12-month period on or after the date of the earliest qualifying β-thalassemia claim. At least 3 days between service dates of RBCT claims were required to be considered discrete RBCTs. Patients with TDT were required to have 1 year of continuous enrollment after their first transfusion to be included. Eligible patients with SCD with recurrent VOCs were required to have ≥2 diagnosed VOCs per year in any 2 consecutive years after and including the first qualifying SCD claim. A VOC was defined as inpatient or outpatient claim of acute chest syndrome, priapism, SCD crisis, or splenic sequestration; at least 3 days between VOC claims were required to be considered discrete VOCs. Eligible patients with SCD with recurrent VOCs were required to have 24 months of continuous enrollment before the second VOC in the second consecutive year and 12 months of continuous enrollment after. Patients with TDT and patients with SCD who met the above criteria and received an HSCT were included in the analysis set. Patients receiving HSCT were identified utilizing relevant procedure codes. The index date was the date of transplant. Patients were followed from the index date to the earliest of end of enrollment, death, or end of study period (March 1, 2020). Demographics were assessed at the index date, and clinical complications, healthcare resource utilization, and costs were descriptively summarized in the post-index period. Costs were based on paid amounts of adjudicated claims and patient cost-sharing and included costs in the 10 days before the index date to account for pre-transplant healthcare services associated with the transplant. Results: Two hundred thirty-four and 3500 patients met the criteria for TDT and SCD with recurrent VOCs, respectively, for a total of 3734 patients. Of that total, 62 patients (1.66%) underwent a transplant and were therefore included in the analysis cohort. Mean patient age at the index date was 12.6 years, and 46.8% were female. A proportion of transplant patients experienced graft versus host disease (GvHD) (37/62; 59.7%), unspecified HSCT complications (33/62; 53.2%), or bone marrow transplant rejection or failure (6/62; 9.7%) post-transplant. Average length of stay for the index HSCT admission was 42 days; in the first year post-transplant, patients averaged 58.3 days in the hospital. Total costs in the first 100 days and 1 year post-transplant were $442,752 and $623,301, respectively. Inpatient costs accounted for 93.7% and 88.7% of costs at 100 days and 1 year, respectively. Conclusions: This retrospective cohort study suggests that only a small proportion of patients with TDT and patients with SCD with recurrent VOCs receive HSCTs. Many patients who undergo transplants experience clinical complications, including graft failure and GvHD, and substantial economic burden. Given the limited utilization and potential safety risks of HSCT, additional curative treatment approaches are needed for patients with TDT and patients with SCD with recurrent VOCs.

A randomized controlled trial of manual versus powered tooth brushing during haematopoietic stem cell transplantation.

AimTo compare manual and powered tooth brushing (MT and PT) with respect to patient compliance to brushing frequency advice, plaque removal and severity of oral mucositis (OM) in patients undergoing hematopoietic stem cell transplantation (HSCT) after high‐dose chemotherapy.Materials & methodsA randomized controlled trial was conducted. Forty‐six patients scheduled to receive myeloablative conditioning regimen before autologous HSCT were included and randomly assigned to control (MT, n = 23) or test (PT, n = 23) groups. Starting at day 1 (day of hospital admission for HSCT), brushing frequency (patient recorded diary), plaque scores (Plaque Control Index) and oral mucositis (Oral Mucositis Nursing Index) were recorded daily. Data for days 1 to 17 were analysed using regression analysis and general linear models.ResultsFew patients maintained 4 times per day brushing, but most brushed at least 2 times per day throughout the study. In PT, overall plaque scores were lower by 6.98% (p = .006) as compared to MT. No differences were seen in OM scores between the groups (p = .968). A small but significant positive correlation was found between plaque scores and OM severity: R 2=0.15 (p < .01).ConclusionsPowered tooth brushing resulted in lower plaque scores, but was not associated with reduced OM severity. Individual plaque scores were positively related to OM severity.

Post-Traumatic Stress Symptoms in Hematopoietic Stem Cell Transplant Recipients

Hematopoietic stem cell transplantation (HCT) is an intensive and potentially curative therapy for patients with hematologic malignancies. Patients admitted for HCT experience a prolonged, isolating hospitalization and endure substantial physical and psychological symptoms. However, there is a paucity of research on the impact of HCT on post-traumatic stress disorder (PTSD) symptoms in transplant recipients. This secondary analysis of 250 patients who underwent autologous and allogeneic HCT examined PTSD using the PTSD Checklist-Civilian measured at 6 months after HCT. We used the Functional Assessment of Cancer Therapy-Bone Marrow Transplant, and the Hospital Anxiety and Depression Scale to assess quality of life (QOL) and depression and anxiety symptoms at the time of admission for HCT, week 2 during hospitalization, and 6 months after HCT. We used multivariate regression models to assess factors associated with PTSD symptoms. Given collinearity between QOL, depression, and anxiety symptoms, we modeled these separately. The rate of clinically significant PTSD symptoms at 6 months after HCT was 18.9% (39/206). Participants with clinically significant PTSD symptoms experienced hypervigilance (92.3%), avoidance (92.3%), and intrusion (76.9%) symptoms. Among patients without clinically significant PTSD symptoms, 24.5% had clinically significant hypervigilance symptoms and 13.7% had clinically significant avoidance symptoms. Lower QOL at time of HCT admission (B=-0.04, P=.004) and being single (B=-3.35, P=.027) were associated with higher PTSD symptoms at 6 months after HCT. Higher anxiety at time of HCT admission (B=1.34, P <.001), change in anxiety during HCT hospitalization (B=0.59, P =.006), and being single (B=-3.50, P=.017) were associated with higher PTSD symptoms at 6 months. In a separate model using depression, younger age (B=-0.13, P=.017), being single (B=-3.58, P=.018), and higher baseline depression symptoms were also associated with higher PTSD symptoms at 6 months (B=0.97, P < .001). Approximately one fifth of patients undergoing HCT experience clinically significant PTSD symptoms at 6 months after transplantation. The prevalence of hypervigilance and avoidance symptoms are notable even among patients who do not have clinically significant PTSD symptoms. Interventions to prevent and treat PTSD symptoms in HCT recipients are clearly warranted.

Disparities in the Use of Allogeneic Hematopoietic Stem Cell Transplant Among Children, Adolescents, and Young Adults with Acute Leukemia in California

Introduction: Previous literature suggests that allogeneic hematopoietic stem cell transplant (HCT) utilization rates are lower amongst Hispanic and Black compared to non-Hispanic White (NHW) cancer patients. However, no previous studies have focused explicitly on the pediatric and adolescent young adult (AYA) population. We sought to examine utilization of HCT by race/ethnicity using the California Cancer Registry (CCR) and the Office of Statewide Health Planning and Development (OSHPD) hospitalization database. We hypothesized that Black and Hispanic patients with acute leukemia less frequently receive HCT than NHW patients. Methods: Using population-based data from California, a retrospective cohort of patients aged 0-39 years with acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL) diagnosed between 2000 and 2015 was assembled. The primary exposure was a composite of race/ethnicity with NHW patients as the reference group. The primary outcome was receipt of first HCT, defined by diagnosis codes in OSHPD or treatment in the CCR. Logistic regression analyses were used to estimate odds ratios (OR) and corresponding 95% confidence intervals (CI). Multivariable models were adjusted for race/ethnicity, age, sex, year of diagnosis, leukemia type, insurance type at diagnosis, rurality, and neighborhood socioeconomic status at diagnosis (SES). Results: Among 7,183 patients (4,790 with ALL and 2,393 with AML), 21% (16% of ALL patients and 31% of AML patients) underwent HCT. Distributions of insurance type and neighborhood SES differed by race/ethnicity with a higher proportion of Black and Hispanic patients having Medicaid insurance and living in lower SES neighborhoods. In univariate analyses, Black and Hispanic race/ethnicity were associated with decreased likelihood of receiving HCT (OR 0.70 95% CI 0.53, 0.94 and OR 0.77 95% CI 0.68, 0.88, respectively) and Asian race was associated with increased likelihood of HCT (OR 1.29 95% CI 1.07, 1.56) compared to NHW patients. In the multivariable model, there was no statistically significant difference in receipt of HCT among Hispanic patients, but disparities persisted among Black patients (Table 1). Uninsured patients and those in the lowest SES quintile were also less likely to receive HCT, while older age and AML were associated with HCT receipt. In analyses stratified by age and leukemia type, we found that the disparities in receipt of HCT among Black patients was largely driven by patients &amp;gt;20 years old (adjusted OR 0.50 95% CI 0.33, 0.78). These analyses also revealed that the increased likelihood of HCT among Asian/PI patients was driven by patients &amp;lt;21 years old with ALL (adjusted OR 1.59 95% CI 1.07, 2.38). Among those who did undergo HCT, Hispanic patients had a longer initial HCT admission (39 v. 35 days, p&amp;lt; 0.0001) and more frequent readmissions (32% with &amp;gt;2 readmissions in the first year post-HCT v. 25%, p=0.005) compared to NHW patients. Conclusions: HCT is a potentially curative treatment for high-risk acute leukemia; thus the observed racial and SES disparities in receipt of HCT may contribute to disparities in leukemia survival. More detailed disease, treatment, and relapse data would provide a better understanding of the etiology of our findings and allow for reduction of existing disparities through improved access to HCT. Disclosures Muffly: Servier: Research Funding; Amgen: Consultancy; Adaptive: Research Funding. Wun:Glycomimetics, Inc.: Consultancy.

Post-traumatic stress symptoms in hematopoietic stem cell transplant (HCT) recipients.

7505 Background: Patients admitted for HCT, an intensive and potentially curative therapy for hematologic malignancies, experience a prolonged, isolating hospitalization and endure substantial physical and psychological symptom burden. However, data are limited regarding long-term post-traumatic stress (PTSD) in HCT survivors and its risk factors. Methods: We conducted a secondary analysis examining longitudinal data from 250 patients who underwent autologous and allogenic HCT. We used the Post-Traumatic Stress Checklist (PTSD-CL) to assess for PTSD symptoms at six months post-HCT. We used the Functional Assessment of Cancer Therapy—Bone Marrow Transplant (FACT-BMT), and the Hospital Anxiety and Depression Scale to assess quality of life (QOL), depression, and anxiety symptoms at the time of admission for HCT, at week-2 during hospitalization, and at six months post-HCT. We used multivariate regression models to assess factors associated with PTSD symptoms, modeling QOL, depression, and anxiety symptoms separately given their collinearity. Results: The mean age was 56.3 (SD = 13.3). The rate of clinically significant PTSD symptoms at six months post-HCT was 18.9% and these patients experienced hypervigilance (92.3%), avoidance (92.3%), and intrusion (76.9%) symptoms. Among patients without clinically significant PTSD symptoms, 24.5% and 13.7% had clinically significant hypervigilance and avoidance symptoms, respectively. Lower QOL at time of HCT admission (B = -0.04, P = 0.004), and being single (B = -3.35, P = 0.027) were associated with higher PTSD symptoms at six months post-HCT. Higher anxiety at time of HCT admission (B = 1.34, P &lt; 0.001), change in anxiety during HCT hospitalization (B = 0.59, P = 0.006), and being single (B = -3.50, P = 0.017), were associated with higher PTSD symptoms at six months. In a separate model, younger age (B = -0.13, P = 0.017), being single (B = -3.58, P = 0.018), and higher baseline depression symptoms were also associated with higher PTSD symptoms at six months (B = 0.97, P &lt; 0.001). Conclusions: Approximately one fifth of patients undergoing HCT experienced clinically significant PTSD symptoms at six months post-transplant. Patients’ baseline QOL and psychological symptoms emerged as important predictors of their risk for PTSD at six months post-HCT. Thus, interventions to prevent and treat PTSD symptoms in HCT recipients are clearly warranted.

Pre-Transplant Baseline Platelet Count and the Number of Peri-HSCT Transfusions Are Associated with an Increased Disease-Free Mortality Rate in a Large Pediatric Cohort

<h3>Introduction</h3> Platelets play a key role in the innate immune system as a source of pro-inflammatory cytokines. Lower platelet counts are associated with higher mortality in hospitalized adults with a variety of diseases, and platelet count <50,000 K/uL on arrival to the intensive care unit in recipients of allogeneic hematopoietic stem cell transplant (HSCT) is associated with decreased survival. Transfusion of platelets is common after HSCT for prevention and management of bleeding. <h3>Objective</h3> We hypothesized that platelet count prior to initiation of conditioning influences post-transplant outcomes, in part by increasing the need for platelet transfusions. <h3>Methods</h3> We retrospectively analyzed 388 patients undergoing first allogeneic HSCT at Cincinnati Children's. The last non-transfused platelet count at the time of admission for HSCT or start of conditioning regimen was considered the baseline platelet count (BPC). Patients transplanted for bone marrow failure syndromes were excluded due to underlying cytopenias. <h3>Results</h3> 35.8% of the cohort was transplanted for malignancy, 45.3% immunodeficiency, 11.6% hemoglobinopathies, and 6.7% genetic conditions. 114/388 patients in the cohort died (29%). Leading cause of death was acute graft-vs-host disease (aGVHD) followed by organ failure, primary disease, infection, and chronic GVHD (Fig 1a). BPC was significantly lower in deceased patients with no difference seen in baseline hemoglobin (Fig 1b). BPC correlated with the number of platelet transfusion by day +14 after HSCT, with a correlation coefficient of -0.49 (p < 0.001). BPC and the number of peri-transplant platelet transfusions were strongly associated with overall survival (OS) and non-relapse mortality (NRM), while baseline absolute neutrophil count (ANC) and conditioning regimen showed no association with OS (Fig 1c, d; Fig 2). Neither BPC nor the number of platelet transfusions influenced the risk for developing thrombotic microangiopathy (TMA) but lower BPC did increase the risk for developing moderate and especially severe GVHD (Fig 2). To investigate if low BPC is simply a marker for more ill and higher risk patient, we analyzed the subcohort of patients with a BPC in the normal range (> 135 K/uL). Lower BPC and the number of platelet transfusions were still associated with the risk for OS and NRM (Fig 3) <h3>Conclusion</h3> In a large cohort, lower BPC but not baseline hemoglobin or ANC are associated with more platelet transfusions and increased risk for NRM and worse OS. While platelet transfusions have previously been implicated in endothelial damage, this effect is independent of TMA risk. BPC is associated with the risk for GVHD, which is the leading cause of death in the cohort, although this appears independent of transfusion burden. Mechanistic studies are ongoing but these data suggest the need for thoughtful consideration of prophylactic platelet transfusion thresholds.

A Single-Center Experience and Literature Review of Management Strategies for Clostridium difficile Infection in Hematopoietic Stem Cell Transplant Patients

The aim of our study is to evaluate risk factors associated with the development of C. difficile infection (CDI) in hematopoietic stem cell transplant (HSCT) patients, determine its incidence and report outcomes of CDI in our patient population. We performed a retrospective review of medical records of adult HSCT recipients diagnosed between 2013 and 2016 at our center. Logistic regression models were used to determine the relationship between risk factors and the odds of CDI. The overall incidence of CDI in HSCT patients was 9.4%. The incidence of CDI was higher in allogeneic HSCT (20%) versus autologous HSCT (4.8%). No statistically significant differences in age, gender, cancer type, transplant type were found between those who developed CDI and those who did not. However, patients with CDI had a longer length of stay (25 days) and used more antibiotics (30 days prior to and during admission for HSCT) than non-CDI patients (19 days). Only two of 17 patients (11.8%) with CDI experienced recurrence among 180 patients after HSCT. No patient suffered from toxic megacolon or ileus and no patient underwent colectomy. There was no mortality associated with CDI at our center. CDI has an incidence rate of 9.4% in HSCT recipients. Established risk factors including age, gender, cancer type, and transplant type were not identified as risk factors in our population. However, longer LOS and use of greater than four lines of antibiotics were observed among those with CDI compared to those without CDI.

Morbidity, Mortality, and Healthcare Utilization in a National Cohort of Pediatric Patients with Hemophagocytic Lymphohistiocytosis Who Received Hematopoietic Stem Cell Transplant

Background Hemophagocytic lymphohistiocytosis (HLH) is a severe life threatening hyper-inflammatory syndrome of abnormal immune activation and dysregulation if untreated. The 5-year probability of survival (pSu) obtained from HLH registries and treatment protocols HLH-94 and HLH-2004 ranges from 21%-64%, with improved 5-year pSu of up to 70% following hematopoietic stem cell transplant (HSCT) (Arico et al., Trottestam et al., Bergsten et al.). Despite significant advances in the management of HLH over time, survival remains low and the extent of disease morbidity and healthcare utilization is poorly characterized. In this study, we sought to investigate morbidity, mortality, and the healthcare burden in children and adolescents with HLH who underwent HSCT. Methods Using the Pediatric Health Information System (PHIS) database, we identified patients under the age of 21 years admitted between 01/01/2004 and 09/30/2018 with a primary or secondary ICD-9 or ICD-10 diagnosis codes for HLH, as well as concurrent medication charges for both dexamethasone and etoposide in the same encounter. We then identified the patients who underwent HSCT to further analyze them. We abstracted data on demographics, hospitalizations, HSCT related complications, mortality, resource utilization and costs. Results were summarized using descriptive statistics. Time to HSCT was calculated as elapsed time from the admission date of the initial encounter to the date of the encounter in which there was a procedure code for HSCT. Time to mortality event was calculated as elapsed time from the admission date of the initial encounter to the discharge date of the encounter in which mortality occurred. The PHIS database provides an encrypted patient medical record number; thus, we were able to follow patients over time. This allowed for a better visualization of the patient's hospitalizations trend over 14 years. Results A total of 493 patients met inclusion criteria for HLH during the study period from 52 children's hospitals. The majority of patients (n = 284, 58%) were less than 5 years of age. Of these, 136 patients (28%) underwent HSCT with 155 hospital encounters, including readmissions. The median age at the time HSCT was 2 years (IQR; 0-9 years) and there were 82 males (60%). The median time to HSCT was 126 days (IQR: 75-193 days) and the average length of stay for the initial HSCT hospitalization was 61.1 days. Median initial HSCT hospitalization cost was $463,630 (IQR; 230,795 - 558,533). ICU care was required for 71 (46%) of patients. Overall, 91 (67%) patients developed transplant-related complications, which included infections, sinusoidal obstruction syndrome or graft versus host disease (Table 1). Mortality after HSCT was 22% (n=30) with an increased mortality observed with advanced age at the time of HSCT (Figure 1). The median time to death after the initial HSCT admission was 65 days (IQR; 56-94 days). Conclusion This is a large in-patient cohort of pediatric patients with HLH who underwent HSCT in the US. We observed an improved overall mortality after HSCT in this population compared to previous studies. However, morbidity (particularly from infections) and heath care resource utilization remain high. This stresses the importance of novel therapeutic approaches to improve not only patient survival but also long-term quality of life. Planned future analysis of this database will be aimed at assessing treatment variability; morbidity and mortality by treatment regimen, time to HSCT, and HSCT preparative regimen; and risk factors associated with mortality in pediatric patients with HLH who do and do not undergo HSCT. Disclosures No relevant conflicts of interest to declare.

Opiate and Benzodiazepine Use during Hospitalization for Hematopoietic Stem Cell Transplantation (HSCT) Is Associated with Adverse Health Related Outcomes

▪INTRODUCTION:Significant burden of pain syndromes are reported in patients with hematological malignancies undergoing HSCT mostly due to underlying disease and associated treatments. Opioid analgesics and benzodiazepines are routinely used for symptomatic management in this patient population. The use of narcotic analgesics and benzodiazepines in non-transplant hospitalized patients has been shown to adversely affect health related outcomes such as length-of-stay (LOS), falls and other complications. However, there is a significant knowledge gap regarding the patterns of opioid and benzodiazepine use and their impact on health outcomes in HSCT patients.METHODS:We identified 275 patients from the year 2015-2018 who underwent HSCT (allogeneic and autologous transplants) at our center for a variety of hematological malignancies. Opioid exposure was defined in three groups of patients 1) Opioid naïve: those did not report prior use of opioid at admission and who were not prescribed opioid during hospitalization, 2) Previous Opioid users: those who reported active use of opioid at admission and continued during hospitalization 3) New Opioid users: Patients who did not report opioid use at admission but were prescribed opioid during hospitalization. Multivariable analysis was performed to identify differences in opioid status, opioid use, benzodiazepine use, disease diagnosis, Karnofsky score, gender, age, race, and marital status with associated complications (Poisson regression), emergency department visits (Logistic Regression) and length of stay (Ordinal Logistic Regression) Figure 1 and Figure 2.RESULTS:The median age of patients was 59 (range: 25-74 ) years with slight male predominance (57%). Patients undergoing autologous transplants for multiple myeloma (MM) comprised 48% of the population. The majority (72 %) were exposed to opioid during hospitalization. Ninety two percent of the opioid naïve population (28% of the total population) underwent autologous transplant. Conversely, 36% of patients undergoing autologous transplants never received opiates during hospitalization as compared to 7% of those who received an allogeneic transplant. Median morphine milligram equivalent daily dose was 3.1 mg. Median diazepam equivalent daily dosage in patients that were opiate exposed was 2.07 milligram. Of the total transplant population, 55% received benzodiazepine concurrently with opiates during hospitalization. 76 % of the population was exposed to both opioid and benzodiazepine. Twenty five percent of those who were exposed to opioid did not receive benzodiazepines.Sixty four percent of the MM patients were exposed to opioid of which majority (59%) were previous opioid users. Of the non-MM patients undergoing HSCT, 80% were exposed to opioid of which 36% were previous opioid users and 64% were new users. A wide range of complications from neutropenic fever to death, were seen in 89% of all patients (opioid users and non-users) but all the falls occurred in patients who were on opioid medications. Autologous transplant recipients had higher odds of having a greater number of complications compared to Allogeneic transplant patients (OR 1.25, 95% CI: 1.01 - 1.55, p=0.04), as well as a reduced odds of having a medium or high length of stay (OR 0.03, 95% CI: 0.02 - 0.07). Of the opioid naïve patients, 6% presented to the ED within 30 days of discharge versus 15% of those that were exposed to opiates during hospitalization. Benzodiazepine use at admission for HSCT was associated with greater odd of presenting to ED within 30 days of discharge (OR 3.94, 95% CI: 1.55-10.04) and this was more significant in patients with MM (OR 4.08, 95% CI: 1.01-16.44). Finally, we also saw a trend towards longer stay in patients who were exposed to opioids as compared to opioid naïve (40% vs. 17%).CONCLUSION:Our study, albeit limited due to its retrospective design, is among the first to report the patterns of use and the impact of opioids and benzodiazepines in patients undergoing HSCT. Our results indicate that the use of these medications is frequent in this population and as in the non-transplant hospitalized patients and is associated with more emergency room visits post discharge, along with other potentially adverse outcomes. DisclosuresKharfan-Dabaja:Incyte Corp: Speakers Bureau; Seattle Genetics: Speakers Bureau; Alexion Pharmaceuticals: Speakers Bureau. Ailawadhi:Amgen: Consultancy; Pharmacyclics: Research Funding; Celgene: Consultancy; Takeda: Consultancy; Janssen: Consultancy.

1581. Impact of Colonization with Fluoroquinolone-Resistant Enterobacteriaceae on the Risk of Gram-Negative Bacteremia in Hematopoietic Stem Cell Transplant Recipients Who Receive Prophylactic Levofloxacin

BackgroundFluoroquinolone (FQ) prophylaxis is widely used to prevent bloodstream infections (BSIs) in neutropenic patients undergoing hematopoietic stem cell transplantation (HCT). In order to assess whether increasing FQ resistance threatens the effectiveness of FQ prophylaxis, we screened HCT recipients for colonization with FQ-resistant Enterobacteriaceae (FQRE) and assessed the impact of colonization on the risk of BSI.MethodsWe collected stool samples on admission for HCT and weekly until neutrophil engraftment from patients at NewYork-Presbyterian Hospital/Weill Cornell Medical Center from November 2016 to March 2018. Patients received FQ prophylaxis during neutropenia. Perianal swabs were used when stool was unavailable. Stool and swab samples were plated onto MacConkey agar with 1 μg/mL ciprofloxacin, and colonies were identified and underwent antimicrobial susceptibility testing. We determined the prevalence of colonization with FQRE on admission for HCT, the risk of acquiring FQRE, and compared the risk of BSI during the transplant admission in colonized and noncolonized patients.ResultsWe evaluated 178 HCT recipients and found that 35 (20%) had pre-transplant FQRE colonization (allogeneic: 20/89, 22%; autologous: 15/89, 17%). Thirty FQRE (86%) were Escherichia coli, 5 (14%) were Klebsiella pneumoniae, and 13 (37%) were extended-spectrum β-lactamase producers. Five (14%) of the 35 patients with pre-transplant FQRE colonization developed BSI due to an Enterobacteriaceae, and all bloodstream isolates had identical susceptibility profiles to the colonizing FQRE. In contrast, only one (1%) of 143 patients without pre-transplant FQRE colonization developed Enterobacteriaceae BSI (P = 0.001). Patients with pre-transplant FQRE colonization also had higher rates of any Gram-negative BSI (20% vs. 1%, P < 0.001), but did not have increased risk of Gram-positive BSI (6% vs. 11%, P = 0.5). Of 123 patients without initial FQRE colonization who had follow-up samples collected, 10 (8%) acquired FQRE during post-HCT neutropenia.ConclusionFQRE colonization is common on admission for HCT and is associated with decreased effectiveness of levofloxacin prophylaxis in preventing Gram-negative BSI during post-transplant neutropenia.Disclosures M. J. Satlin, Hardy Diagnostics: Grant Investigator, Research support; Allergan: Grant Investigator, Grant recipient; Merck: Grant Investigator, Grant recipient; Biomerieux: Grant Investigator, Grant recipient; Achaogen: Consultant, Consulting fee. R. Malherbe, Hardy Diagnostics: Employee, Salary. S. G. Jenkins, Merck: Grant Investigator, Grant recipient. L. F. Westblade, Accelerate Diagnostics: Grant Investigator, Grant recipient; Biomerieux: Grant Investigator, Grant recipient; Allergan: Grant Investigator, Grant recipient; Merck: Grant Investigator, Grant recipient. T. J. Walsh, Merck: Grant Investigator, Research grant; Atellas: Consultant, Grant Investigator and Scientific Advisor, Consulting fee and Research grant; Gilead: Scientific Advisor, Consulting fee; Allergan: Grant Investigator and Scientific Advisor, Consulting fee and Research grant; Scynexis: Grant Investigator, Research grant; Amplyx: Grant Investigator, Research grant; Shionogi: Scientific Advisor, Consulting fee.

Psychophysical well-being profiles in patients before hematopoietic stem cell transplantation.

The literature offers very few in-depth reports on the time directly before hematopoietic stem cell transplantation (HSCT). Also, researchers have focused on selected aspects of psychophysical well-being and treated the sample as homogeneous. Thus, we chose to investigate distinct multidimensional well-being profiles (including anxiety, depressive symptoms, and health-related quality of life [HRQOL] domains) among patients just before HSCT, as well as profile predictors (generalized self-efficacy) and outcomes (transplant appraisal) on the basis of the transactional stress model. Depression (CES-D), anxiety (HADS-A), HRQOL (EORTC QOL-C30), generalized self-efficacy (GSES), and transplant appraisal (single-item scale referred to threat and challenge) were measured in 290 patients (56.9% male; mean age=47.28, SD=13.79) after admission for HSCT (67.2% autologous). Unconditional and conditional latent profile analyses were applied. Four latent well-being profiles were identified: well-functioning (51%, highest well-being in all aspects), dysfunctional (10%, weakest functioning in all aspects), and 2 profiles with moderate HRQOL and high (5.6%) or low (33.4%) anxiety and depressive symptoms. Generalized self-efficacy predicted profile membership, controlling for demographic and clinical variables. The highest levels were observed in the well-functioning group (P<.01). Appraisal was predicted by latent profile analyses classes: low threat in the well-functioning group (P<.001) and the highest threat and challenge in the dysfunctional group (P<.01). The findings highlight the diverse nature of well-being in pre-HSCT patients and the manner in which transplant appraisal and generalized self-efficacy are related to different profiles of pre-HSCT multidimensional well-being, thus indicating the practical implications of the study.

Viral-induced Hemorrhagic Cystitis After Allogeneic Hematopoietic Stem Cell Transplant.

Hemorrhagic cystitis (HC) is a well-recognized problem that is regularly observed after hematopoietic stem cell transplantation (HSCT). The published data does not report on the potential risk factors for the viral-induced HC that might require prophylactic treatments. We conducted a retrospective analysis of all adult patients who underwent allogeneic HSCT at Jules Bordet Institute between 1992 and 2013. Our institutional protocol consists in monitoring the patient for signs and symptoms of HC on a daily basis during the initial admission for HSCT, then once weekly after discharge until 2 months thereafter. HC was found in 64 patients, of whom 56 (87.5%) had viral-induced HC. The median time between HSCT and HC was 39.5 days (range, 1-2766 days); the median time between detection of a viral infection and HC was 32 days (range, 0-2752 days). In multivariate analysis, HC is correlated to the infection with the BK virus (hazard ratio, 6.0; 95% confidence interval, 5.03-6.90; P= .0001) and the adenovirus (hazard ratio, 4.93; 95% confidence interval, 4.06-5.80; P= .0003). The 5-year overall survival of patients with HC was 36%. The 5-year survival rates were not statistically different between patients with or without HC (25% vs. 39%; P= .20). The presence of the identified risk factors should prompt closer follow-up with screening tests and preventive measures for BK virus and adenovirus infections in patients undergoing HSCT.

Objective Measures of Pre-Transplant Physiologic Fitness Are Strong Predictors of Very-Short Term Transplantation Related Mortality

Background Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy for many hematological malignancies, however high mortality associated with the procedure remains a significant obstacle. Predictors of intermediate- and long-term treatment-related mortality (TRM) have been established, including two well-validated scoring systems (HCT-CI, Sorror 2005; EBMT, Gratwohl 2012). These scores reflect overall comorbidity burden (HCT-CI) and disease status together with specifics of the transplant procedure (EBMT). Early mortality post-HSCT may be related closely to the patient's immediate physiological state at the time of HSCT. We hypothesized that clinical laboratory values taken at the time of admission for HSCT may give a useful representation of physiological age and fitness for transplant, and thus be highly predictive of early (100 day) and very-early (30 day) treatment-related mortality (TRM).Methods This was a retrospective study on a cohort of patients who underwent HSCT at a single center for any indication between 2000 and 2014. Hematology and chemistry laboratory data were collected from the time of admission for transplantation, prior to the initiation of conditioning regimens. Variables representing bone marrow function (neutrophils, platelets, hemoglobin), kidney function (creatinine clearance estimated by EPI), liver function (total bilirubin, AST, ALT), nutritional status (albumin) as well as age were included in a Fine & Gray Competing Risk regression at time-points of 30, 100 and 365 days. Cumulative incidence curves were constructed for variables deemed significant at each time-point.Results A total of 1,045 patients were included in this study. The median patient age was 52 (IQR 39-60). Myeloablative conditioning was used for 274 patients (26.2%) while reduced-intensity conditioning was used for 765 patients (73.2%). 568 (54.4%) patients received transplants from sibling donors, and 477 (45.6%) patients received grafts from unrelated donors. Risk associated with individual laboratory biomarkers changed over the course of the first year post-transplantation. Creatinine clearance, albumin and total bilirubin were strong predictors of early mortality (p < 0.01) at 30 days, with hazard ratios of 4.5, 3 and 2.6 respectively. Notably, the prognostic weight of these variables decreased over time. In contrast, the prognostic role of age became evident only later in the first year (table 1). Cumulative incidence of TRM in patients with creatinine clearance < 60 mL/min (fig. 1a) and with albumin < 3.5 g/dL (fig. 1b) showed markedly poorer outcomes over time, with especially strong effect in the immediate aftermath of transplantation.Conclusions Our study demonstrates that common laboratory biomarkers of physiological fitness and biological age are strong determinants of early transplantation-related mortality. These markers are complimentary to existing prognostic models, which utilize broader comorbidity categories (HCT-CI) or specifics of the transplantation procedure (EBMT score) to predict medium and long-term survival trends. Laboratory variables are readily-available objective measures, and may be of particular importance when assessing fitness for the initial transplantation procedure. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Vancomycin-Resistant Enterococcus Colonization and Bacteremia and Hematopoietic Stem Cell Transplantation Outcomes

The association between pre–hematopoietic stem cell transplantation (HSCT) vancomycin-resistant Enterococcus (VRE) colonization, HSCT-associated VRE bacteremia, and HSCT mortality is disputed. We studied 161 consecutive patients with acute leukemia who underwent HSCT at our hospital between 2006 and 2014, of whom 109 also received leukemia induction/consolidation on our unit. All inpatients had weekly VRE stool surveillance. Pre-HSCT colonization was not associated with increases in HSCT mortality but did identify a subgroup of HSCT recipients with a higher risk for VRE bacteremia and possibly bacteremia from other organisms. The major risk factor for pre-HSCT colonization was the number of hospital inpatient days between initial admission for leukemia and HSCT. One-third of evaluable patients colonized before HSCT were VRE-culture negative on admission for HSCT; these patients had an increased risk for subsequent VRE stool surveillance positivity but not VRE bacteremia. Molecular typing of VRE isolates obtained before and after HSCT showed that VRE strains frequently change. Postengraftment VRE bacteremia was associated with a much higher mortality than pre-engraftment VRE bacteremia. Pre-engraftment bacteremia from any organism was associated with an alternative donor and resulted in an increase in hospital length of stay and cost. Mortality was similar for pre-engraftment VRE bacteremia and pre-engraftment bacteremia due to other organisms, but mortality associated with post-engraftment VRE bacteremia was higher and largely explained by associated severe graft-versus-host disease and relapsed leukemia. These data emphasize the importance of distinguishing between VRE colonization before HSCT and at HSCT, between pre-engraftment and postengraftment VRE bacteremia, and between VRE bacteremia and bacteremia from other organisms.

Quality of life and mood predict posttraumatic stress disorder after hematopoietic stem cell transplantation.

During hospitalization for hematopoietic stem cell transplantation (HCT), patients experience a steep deterioration in quality of life (QOL) and mood. To our knowledge, the impact of this deterioration on patients' QOL and posttraumatic stress disorder (PTSD) symptoms after HCT is unknown. We conducted a prospective longitudinal study of patients hospitalized for HCT. They assessed QOL using the Functional Assessment of Cancer Therapy-Bone Marrow Transplantation (FACT-BMT) and depression and anxiety symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9) at the time of admission for HCT, during hospitalization, and 6 months after HCT. We also used the Hospital Anxiety and Depression Scale (HADS) to measure patients' anxiety and depression symptoms at baseline and during HCT hospitalization. The PTSD Checklist was used to assess for PTSD symptoms. Multivariable linear regression models were used to identify predictors of QOL and PTSD symptoms at 6 months. We enrolled 90 of 93 consecutively eligible patients (97%) undergoing autologous and allogeneic HCT. Data at 6 months were available for 67 participants. At 6 months, 28.4% of participants met the criteria for PTSD and 43.3% had clinically significant depression. On multivariable regression analyses adjusting for significant covariates, changes in QOL and depression scores from week 2 of HCT hospitalization to baseline predicted worse QOL (changes in scores between week 2 and baseline [Δ] QOL: β, 0.94 [P<.0001] and Δ PHQ-9: β, -2.59 [P = 0.001]) and PTSD symptoms (Δ QOL: β, -0.40 [P<.0001] and Δ PHQ-9: β, 1.26 [P<.0001]) at 6 months after HCT. Six months after HCT, a significant percentage of patients met the criteria for PTSD and depression. A decline in QOL and an increase in depressive symptoms during hospitalization for HCT were found to be the most important predictors of 6-month QOL impairment and PTSD symptoms. Therefore, managing symptoms of depression and QOL deterioration during HCT hospitalization may be critical to improving QOL at 6 months and reducing the risk of PTSD. Cancer 2016;122:806-812. © 2015 American Cancer Society.

Trends of Venous Thromboembolism (VTE) and Risk Factors for Developing VTE in Pediatric Patients Undergoing Hematopoietic Stem Cell Transplant (HSCT) in children’s Hospitals-a PHIS Database Study

Background: The incidence of venous thromboembolism (VTE) is rising in critically ill children. It is one of the most common hospital acquired complications and the use of thromboprophylaxis remains controversial. Exposure to risk factors including central venous lines, infection/inflammation and prolonged immobilization increases the risk of VTE while underlying coagulopathy, thrombocytopenia, requirement of invasive procedures, organ failure or medications increase the risk of bleeding. Therefore, understanding these risk factors in various subsets of critically ill children is vital to develop VTE prevention strategies. Since Hematopoietic Stem Cell Transplant (HSCT) recipients comprise a subset of patients at high risk of developing VTE due to exposure to the risk factors above, we explored the trends and risk factors for VTE in children undergoing HSCT using a national administrative database during the past decade.Methods: ThePediatric Health Information System (PHIS) database was queried using the ICD-9-CM codes to identify children <=18 years old who underwent HSCT at 40 hospitals from 2004-2013. A step-wise search strategy was developed to identify the subset of patients whose billing codes indicate that they had developed at least one incidence of VTE after discharge or during their HSCT admission. The patient level data (age, gender, ethnicity, pre-HSCT diagnosis) and HSCT related data [Graft versus host disease (GVHD), Veno-occlusive disease (VOD), Cytomegalovirus infection (CMV) and length of stay) was abstracted from the HSCT encounter. Descriptive analyses were performed to compare means, and percentages between VTE and various risk factors. Chi Square and Fisher exact test were used as appropriate. We performed a linear regression analysis to compare the trends of VTE over the last 10 years.Results: A total of 8559 children underwent HSCT from 2004 to 2013. Of these, 450 (5.26%) developed VTE after HSCT discharge. The details of patient characteristics are shown in Table 1. The VTE incidence and 95% confidence intervals by year are shown in figure 1. There was no significant linear change in the trends of VTE in the patients undergoing an HSCT over the last 10 years, (p=0.296), Figure 1. In bivariate analyses, patients who developed VTE were older, had more hematological malignancies, longer length of hospitalization during the encounter and had higher incidence of acute GVHD (aGVHD), chronic GVHD (cGVHD) and VOD (p<0.001).Conclusions: This study showed that despite concerns about rising incidence of VTE in critically ill hospitalized children, the incidence of VTE as defined by the billing codes in the HSCT population has remained stable during the last decade.We have also described that age, prolonged hospitalization and hematological malignancy were associated with occurrence of VTE in this group of patients. The higher incidence of aGVHD, VOD and cGVHD in patients imply that ongoing inflammation predisposes to prothrombotic milieu. These findings warrant consideration prior to implementing VTE prophylaxis in HSCT patients. More prospective studies are needed to explore the utility of primary thromboprophylaxis in this population. Table 1CharacteristicPatients with thrombosisN=450Patients without thrombosisN=8109p-valueAge (years)MeanSt. Deviation9.2 5.98 5.3<0.0001 GenderMaleFemale249 (55%) 201 (45%)4717 (58%) 3392 (42%)0.235EthnicityHispanicNon-hispanicUnknown79 (18%) 221 (49%) 150 (33%)1546 (19%) 3593 (44%) 2970 (37%)0.136DiagnosisAplastic anemiaHematological malignancy(including MDS)NHLBrain tumorSCIDSickle Cell DiseaseThalassemiaOthers24 (5%) 158 (35%) 19 (4%) 23 (5%) 11 (2%) 7 (2%) 0 (0%) 208 (46%)498 (6%) 2412 (30%) 213 (3%) 554 (7%) 166 (2%) 131 (2%) 2 (0.02%) 4133 (51%)0.485 0.017 0.042 0.156 0.564 0.921 0.739Length of stay (days)MeanSt. Deviation59 51.9144 34.06<0.0001Acute GVHD75 (17%)729 (9%)<0.0001Chronic GVHD73 (16%)521 (6%)<0.0001VOD14 (3%)124 (2%)0.009CMV Viremia15 (3%)236 (3%)0.604 [Display omitted] DisclosuresNo relevant conflicts of interest to declare.