Diverse Approaches to Gene Therapy of Sickle Cell Disease.

Sickle cell disease (SCD) results from a single base pair change in the sixth codon of the ß-globin chain of hemoglobin, which promotes aggregation of deoxyhemoglobin, increasing rigidity of red blood cells and causing vaso-occlusive and hemolytic complications. Allogeneic transplant of hematopoietic stem cells (HSCs) can eliminate SCD manifestations but is limited by absence of well-matched donors and immune complications. Gene therapy with transplantation of autologous HSCs that are gene-modified may provide similar benefits without the immune complications. Much progress has been made, and patients are realizing significant clinical improvements in multiple trials using different approaches with lentiviral vector-mediated gene addition to inhibit hemoglobin aggregation. Gene editing approaches are under development to provide additional therapeutic opportunities. Gene therapy for SCD has advanced from an attractive concept to clinical reality.

Hematopoietic stem cell gene therapy improves outcomes in a clinically relevant mouse model of multiple sulfatase deficiency.

Multiple sulfatase deficiency (MSD) is a severe, lysosomal storage disorder caused by pathogenic variants in the gene SUMF1, encoding the sulfatase modifying factor formylglycine-generating enzyme. Patients with MSD exhibit functional deficiencies in all cellular sulfatases. The inability of sulfatases to break down their substrates leads to progressive and multi-systemic complications in patients, similar to those seen in single-sulfatase disorders such as metachromatic leukodystrophy and mucopolysaccharidoses IIIA. Here, we aimed to determine if hematopoietic stem cell transplantation with ex vivo SUMF1 lentiviral gene therapy could improve outcomes in a clinically relevant mouse model of MSD. We first tested our approach in MSD patient-derived cells and found that our SUMF1 lentiviral vector improved protein expression, sulfatase activities, and glycosaminoglycan accumulation. In vivo, we found that our gene therapy approach rescued biochemical deficits, including sulfatase activity and glycosaminoglycan accumulation, in affected organs of MSD mice treated post-symptom onset. In addition, treated mice demonstrated improved neuroinflammation and neurocognitive function. Together, these findings suggest that SUMF1 HSCT-GT can improve both biochemical and functional disease markers in the MSD mouse.

Enterocytozoon bieneusi Infection after Hematopoietic Stem Cell Transplant in Child, Argentina.

We report a case of Enterocytozoon bieneusi infection in a pediatric hematopoietic stem cell transplant recipient in Argentina. Spores were visualized in feces using Calcofluor White and modified trichrome stainings. PCR and sequencing identified E. bieneusi genotype D in fecal samples and liver samples, confirming extraintestinal dissemination of the parasite.

A phase I/II study of adoptive SARS-CoV-2-specific T cells in immunocompromised hosts with or at risk of severe COVID-19 infection.

BACKGROUND: Post-transplant or hematological cancer patients have a higher risk of mortality after infection with ancestral and early variants of severe acute respiratory syndrome (SARS)-CoV-2. Adoptive cell therapy (ACT) with virus-specific T cells (VSTs) could augment endogenous T cell immunity to avoid disease deterioration before viral clearance. METHODS: We established a third-party SARS-CoV-2-specific T cell (COVID-T) bank in 2020 (NCT04351659) using convalescent and/or vaccinated donors. In a phase I/II study (NCT04457726), 13 adult and pediatric patients, acutely positive for SARS-CoV-2 and predicted to have a high chance of mortality, were recruited from September 2021 to February 2022. Twelve patients received a single dose of COVID-T cells, matched on at least 1 HLA. RESULTS: A dose of either 75,000 or 150,000 IFN-γ+CD3+ cells/m2 SARS-COV-2-specific T cells did not cause cytokine release syndrome, acute respiratory distress syndrome, or graft-versus-host disease. In the 8 patients who had detectable donor SARS-COV-2-specific T cells after ACT, none progressed to severe disease or died with COVID-19. In contrast, among the other four patients without evidence of donor micro-chimerism, two died of COVID-19. CONCLUSIONS: Long-acting third-party VSTs from convalescent or vaccinated donors could be expediently produced and might be clinically useful in future pandemics, particularly before global vaccination is implemented.

Impact of rabbit anti-thymocyte globulin (ATG) exposure on outcomes after ex vivo T-cell-depleted hematopoietic cell transplantation in pediatric and young adult patients.

BACKGROUND AIMS: Traditional weight-based dosing of rabbit anti-thymocyte globulin (rATG) used in allogeneic hematopoietic cell transplantation (HCT) to prevent graft-versus-host disease (GVHD) and graft rejection leads to variable exposures. High exposures induce delayed CD4+immune reconstitution (CD4+IR) and greater mortality. We sought to determine the impact of rATG exposure in children and young adults receiving various types of EX-VIVO T-cell-depleted (EX-VIVO-TCD) HCT. METHODS: Patients receiving their first EX-VIVO-TCD HCT (CliniMACS CD34+, Isolex or soybean lectin agglutination), with removal of residual T cells by E-rosette depletion (E-) between 2008 and 2018 at Memorial Sloan Kettering Cancer Center were retrospectively analyzed. rATG exposure post-HCT was estimated (AU*d/L) using a validated population pharmacokinetic model. Previously defined rATG-exposures, <30, 30-55, ≥55 AU*d/L, were related with outcomes of interest. Cox proportional hazard and cause-specific models were used for analyses. RESULTS: In total, 180 patients (median age 11 years; range 0.1-44 years) were included, malignant 124 (69%) and nonmalignant 56 (31%). Median post-HCT rATG exposure was 32 (0-104) AU*d/L. Exposure <30 AU*d/L was associated with a 3-fold greater probability of CD4+IR (P < 0.001); 2- to 4-fold lower risk of death (P = 0.002); and 3- to 4-fold lower risk of non-relapse mortality (NRM) (P = 0.02). Cumulative incidence of NRM was 8-fold lower in patients who attained CD4+IR compared with those who did not (P < 0.0001). There was no relation between rATG exposure and aGVHD (P = 0.33) or relapse (P = 0.23). Effect of rATG exposure on outcomes was similar in three EX-VIVO-TCD methods. CONCLUSIONS: Individualizing rATG dosing to target a low rATG exposure post-HCT while maintaining total cumulative exposure may better predict CD4+IR, reduce NRM and increase overall survival, independent of the EX-VIVO-TCD method.

High CD34-positive cell dose in matched unrelated donor allogeneic hematopoietic stem cell transplant is not associated with graft-versus-host disease or mortality.

BACKGROUND: CD34+ stem cells serve as the primary graft source for allogeneic transplants, with a minimum of 2-4 × 106 cells/kg needed for engraftment. There are conflicting data on outcomes at high stem cell doses, with studies limited by few patients receiving doses far above the minimum target. STUDY DESIGN AND METHODS: In this retrospective, single-center study of patients with hematologic malignancies who underwent matched unrelated donor transplants, we assessed outcomes for engraftment, survival, relapse, and graft-versus-host disease (GVHD) for the highest CD34+ dose quintile (>13 × 106 cells/kg, n = 36) compared to the remaining patients (n = 139). Similar analysis was performed correlating T cell dose and outcomes. RESULTS: There was no difference between the groups in neutrophil engraftment, with a trend toward faster platelet engraftment. There was no significant difference in mortality (adjusted risk ratio [aRR] = 1.02, 95% confidence interval [CI] = 0.85-1.22), relapse (aRR = 1.10, 95% CI = 0.85-1.42), or overall survival by Kaplan-Meier analysis (p = .44). High CD34+ dose was not associated with higher incidence of acute GVHD (aRR = 0.99 grades II-IV, aRR = 1.18 grades III-IV) or chronic GVHD (aRR = 0.87 overall, RR = 1.21 severe). There was limited correlation between CD34+ and T cell dose (R2 = .073), and there was no significant difference in survival, relapse, or GVHD in the highest T cell dose quintile (n = 33) compared to the remaining quintiles (n = 132). DISCUSSION: We found no difference in survival, relapse, or GVHD incidence or severity in patients receiving CD34+ doses above prior cutoffs reported in the literature. These data do not support the routine use of graft CD34+ dose reduction.

Temporal trends in critical care utilization and outcomes in allogeneic hematopoietic stem cell transplant recipients.

Historically, the prognosis of allogeneic hematopoietic stem cell transplant (allo-HCT) recipients who require intensive care unit (ICU) admission has been poor. We aimed to describe the epidemiological trends of ICU utilization and outcomes in allo-HCT patients. We conducted a retrospective cohort study including adults (≥ 18) undergoing allo-HCT between 01/01/2005 and 31/12/2020 at Mayo Clinic, Rochester. Temporal trends in outcomes were assessed by robust linear regression modelling. Risk factors for hospital mortality were chosen a priori and assessed with multivariable logistic regression modelling. Of 1,249 subjects, there were 486 ICU admissions among 287 individuals. Although older patients underwent allo-HCT (1.64 [95% CI: 1.11 to 2.45] years per year; P = 0.025), there was no change in ICU utilization over time (P = 0.91). The ICU and hospital mortality rates were 19.2% (55/287) and 28.2% (81/287), respectively. There was a decline in ICU mortality (-0.38% [95% CI: -0.70 to -0.06%] per year; P = 0.035). The 1-year post-HCT mortality for those requiring ICU admission was 56.1% (161/287), with no significant difference over time, versus 15.8% (141/891, 71 missing) among those who did not. The frequency and duration of invasive mechanical ventilation (IMV) declined. In multivariable analyses, higher serum lactate, higher sequential organ failure assessment (SOFA) scores, acute respiratory distress (ARDS), and need for IMV were associated with greater odds of hospital mortality. Over time, rates of ICU utilization have remained stable, despite increasing patient age. Several trends suggest improvement in outcomes, notably lower ICU mortality and frequency of IMV. However, long-term survival remains unchanged. Further work is needed to improve long-term outcomes in this population.

Isolated massive pleural effusion as a manifestation of chronic graft versus host disease successfully treated with corticosteroid.

Isolated pleural effusion is a rare manifestation of chronic graft versus host disease (cGVHD) after hematopoietic stem cell transplantation (HSCT). We herein report a 58-year-old woman presenting with massive pleural effusion approximately 1 year after allogeneic HSCT, who was successfully treated with corticosteroid. She had discontinued tacrolimus approximately 1 month before she presented with pleural effusion, which was attributed to cGVHD after a thorough exclusion process. This case illustrates a unique manifestation of atypical cGVHD and highlights the need for prompt therapy initiation.

Allogeneic hematopoetic stem cell transplant for patients with refractory T-Cell lymphomas.

OBJECTIVE: Allogeneic stem cell transplantation (allo-SCT) may have a curative potential due to the graft versus lymphoma effect. In this study, we aimed to compare transplant outcomes between refractory-T-NHL (ref-NHL) and Chemosensitive-T-NHL (CS-T-NHL). MATERIALS AND METHODS: We retrospectively reviewed the records of 26 ref-NHL and 29 CS-T-NHL consecutive patients who underwent allo-SCT at our center and compared the transplant outcomes between the groups. RESULTS: All patients were heavily pretreated with 27% of patients relapsing post-auto-SCT and two patients in the ref-T-NHL post-allo-SCT. Patients were transplanted mainly from unrelated donors. There were no differences in leucocytes and platelet engraftment between the two groups. At 3 years, the relapse incidence was 34% in Ref-TNHL and 19% in CS-TNHL (p = .33), with non-relapse mortality rates of 28% and 22%, respectively (p = .52). Female patients and those with a previous auto-SCT had lower relapse incidence (p = .045, p = .003). The 3-year overall survival was 39% in Ref-TNHL and 56% in CS-TNHL (p = .15). Trends for improved progression-free survival (PFS) and graft-versus-host disease relapse-free survival (GRFS) were observed in the CS-TNHL group (PFS: 60% vs. 30%, p = .075; GRFS: 38% vs. 21%, p = .1). CONCLUSION: Acknowledging the retrospective nature of our study, our results indicate that allo-SCT has a curative potential in patients with T-NHL even in refractory status.

Coping with stress styles and the level of perceived stress in hematopoietic cell transplant patients.

OBJECTIVE: Hematopoietic stem cell transplantation (HSCT) is considered an integral part of therapy in many hematological and non-hematological malignancies. The procedure can be highly stressful for patients. The primary objective of this study was to compare stress assessments in HSCT patients, depending on their stress coping style (CS) and type of treatment (autologous vs. allogeneic HSCT). METHODS: A short longitudinal study was conducted between May 2021 and June 2023 among patients with hematological cancers undergoing HSCT. The study involved four time points: the day of admission to hospital - T1, the day before HSCT - T2, 6 days after HSCT - T3, and the day of discharge - T4. Participants completed the Coping Inventory for Stressful Situations (CISS) on T1, and the Distress Thermometer (DT) on T1-T4. Descriptive statistics and a repeated measures ANOVA were conducted. RESULTS: A total of 128 participants completed the study: 54.2% female, mean age 48.7 years. They were divided into: (1) five groups based on their CS: task-oriented, emotion-oriented, avoidance-oriented, mix-oriented, differential-oriented; (2) two groups based on treatment type. The analyses showed significant differences in stress between the CS study groups (p = 0.001). The emotion-oriented group had the highest stress levels during the hospitalization period. There was also a significant time effect (p < 0.001): stress levels increased during the hospitalization period, peaking 6 days after HSCT, and decreased at discharge. CONCLUSIONS: Stress levels depend on coping styles and time points during the hospitalization period, which should be taken into account in planning psychological interventions for HSCT patients.

The impact of levofloxacin prophylaxis on empiric intravenous antibiotic use in pediatric hematopoietic stem cell transplant recipients.

Levofloxacin prophylaxis during periods of neutropenia in pediatric hematopoietic stem cell transplant (HSCT) may reduce the number of febrile episodes and use of empiric intravenous antibiotics (EIA); however, the literature is conflicting. This retrospective review compared EIA use before and after implementation of levofloxacin prophylaxis at a children's hospital. Levofloxacin prophylaxis was associated with reduced use of certain EIA; however, did not reduce the number of positive blood cultures or clinical deteriorations. Therefore, levofloxacin prophylaxis may have implications for the stewardship of broad-spectrum intravenous antibiotics used in pediatric HSCT.

Can extending time between vital sign checks improve sleep in hematopoietic stem cell transplant patients? Testing feasibility, acceptability, and preliminary efficacy.

BACKGROUND: Patients undergoing hematopoietic stem cell transplant (HSCT) experience barriers to quality sleep. Frequent vital sign checks are necessary early posttransplant given risk of complications but can disrupt sleep. This study tested feasibility and acceptability of extending time between checking vitals (EVs) from every 4 to every 6 h to improve sleep. PROCEDURE: HSCT patients ages 8-21 years (N = 50, mean age = 14.06, SD = 3.58) and their caregivers were enrolled 1-2 days prior to transplant, and 40 patients completed the 15-day study (NCT04106089). Patients wore an actigraph to estimate sleep and provided self- and caregiver-report of sleep. Sleep was observed for nights 0 to +4 posttransplant, and patients were then randomized to EVs either Days +5 to +9 or +10 to +14. Patients were assessed daily for medical eligibility to receive EVs; on days patients were eligible, nightshift nurses (N = 79) reported EV acceptability. RESULTS: Of 200 potential nights for EVs (5 nights x 40 patients), patients were eligible for EVs on 126 nights (63% of eligible nights), and patients received EVs on 116 (92%) of eligible nights. Most patients received EVs ≥3 nights (n = 26, 65%, median = 3 nights). Most patients (85%), caregivers (80%), and nurses (84%) reported that patients used the additional 2 h during EVs for sleep, with reporters indicating moderate to high acceptability. There was preliminary evidence of efficacy indicated by caregiver-reported sleep disturbance and actigraphy-estimated improvements in sleep efficiency during EVs. CONCLUSION: Extending time between vitals checks is highly acceptable to patients, caregivers, and nurses, and may offer a feasible approach to improve sleep in pediatric HSCT.

Invasive fungal infections are rare in pediatric and young adult autologous hematopoietic stem cell transplant patients.

BACKGROUND: Pediatric and young adult patients undergoing autologous hematopoietic stem cell transplant (auto-HSCT) face a crucial, yet understudied, risk of invasive fungal infections (IFI), especially compared to allogeneic transplants. This gap underscores the need for research in pediatric patients undergoing auto-HSCT. Our objective was to evaluate the incidence of IFI in pediatric and young adult patients during the first year after auto-HSCT. MATERIALS AND METHODS: We conducted a single-center retrospective analysis of 150 pediatric and young adult auto-HSCT patients who underwent transplant from January 2013 to January 2023. We focused on IFI incidence within the first-year post transplant, using the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria for IFI identification. RESULTS: Among the 150 patients analyzed, with 240 unique transplant episodes, the primary indication was neuroblastoma (37.3%), and micafungin was extensively used for prophylaxis (82.7%). There was an absence of IFI from yeast and mold species, suggesting a low IFI risk in this cohort. The incidence of IFI in pediatric auto-HSCT recipients receiving micafungin primary antifungal prophylaxis is rare. CONCLUSIONS: The findings advocate for further research to refine prophylaxis guidelines and highlight the need for individualized risk assessment to optimize post-transplant care.

Social determinants of health predict health outcomes following pediatric allogeneic hematopoietic stem cell transplant.

BACKGROUND: Pediatric hematopoietic stem cell transplantation (HCT) is an intensive medical procedure that places substantial financial and logistical burdens on families and is associated with significant health risks, such as graft-versus-host disease (GVHD), and infections. The influence of the social determinants of health (SDoH) on outcomes following pediatric HCT is understudied. This study aimed to examine whether SDoH predicts outcomes following pediatric HCT. PROCEDURE: Data were collected from 84 children who received HCT (Mage  = 5.8 years, SD = 3.7) and their primary caregiver. Detailed demographic information was collected from caregivers at baseline, and child health information was extracted from the electronic medical records. Multivariate logistic regression was used to examine the association between SDoH and health outcomes within a 24-month period following pediatric HCT. RESULTS: After controlling for malignancy as reason for transplant and donor type, lower family income predicted the incidence of chronic GVHD. Neighborhood deprivation, total family income, public health insurance, caregiver relationship status, caregiver educational attainment, and perceived family financial difficulties did not predict acute GVHD or the number of infections. CONCLUSIONS: Total family income is a simple family indicator of SDoH that predicts chronic GVHD after pediatric allogeneic HCT. These findings provide further support for the importance of screening of child and family SDoH risks to ensure that fundamental needs can be met to mitigate potential health disparities for up to 2 years following pediatric HCT.

Chronic disseminated candidiasis in a patient with acute leukemia - an illustrative case and brief review for clinicians.

Chronic disseminated candidiasis (CDC) is a severe but rarely seen fungal infection presenting in patients with hematologic malignancies after a prolonged duration of neutropenia. A high index of suspicion is required to diagnose CDC as standard culture workup is often negative. While tissue biopsy is the gold standard of diagnosis, it is frequently avoided in patients with profound cytopenias and increased bleeding risks. A presumptive diagnosis can be made in patients with recent neutropenia, persistent fevers unresponsive to antibiotics, imaging findings of hypoechoic, non-rim enhancing target-like lesions in the spleen and liver, and mycologic evidence. Here, we describe the case of an 18-year-old woman with relapsed B-cell acute lymphoblastic leukemia treated with re-induction chemotherapy who subsequently developed CDC with multi-organ involvement. The diagnosis was made based on clinical and radiologic features with positive tissue culture from a skin nodule and hepatic lesion. The patient was treated for a total course of 11 months with anti-fungal therapy, most notably amphotericin B and micafungin, and splenectomy. After initial diagnosis, the patient was monitored with monthly CT abdomen imaging that showed disease control after 5 months of anti-fungal therapy and splenectomy. The diagnosis, treatment, and common challenges of CDC are outlined here to assist with better understanding, diagnosis, and treatment of this rare condition.

Keratinocyte carcinomas in survivors of childhood cancer: A report from the childhood cancer survivor study.

BACKGROUND: Childhood cancer survivors (CCS) are at increased risk for keratinocyte carcinomas (KC) however, the long-term incidence of single and multiple KC is not well established. OBJECTIVE: Identify risk factors and quantify KC cumulative incidence and multiple-incidence burden in CCS. METHODS: KC were identified among Childhood Cancer Survivor Study participants, a cohort of 5-year cancer survivors diagnosed <21 years of age between 1970 and 1999 in North America. Cumulative incidence was estimated and multivariable models assessed relative rates of KC associated with survivor and treatment characteristics. RESULTS: Among 25,658 participants, 1446 developed 5363 KC (93.5% basal cell carcinoma, 6.7% squamous cell carcinoma; mean age 37.0 years (range 7.3-67.4), mean latency 25.7 years; 95.3% White and 88.4% with radiotherapy). Mean lesion count was 3.7 with 26.1% experiencing ≥4. Radiotherapy imparted a 4.5-fold increase in the rate of any KC and 9.4-fold increase in the rate of ≥4 KC. Allogeneic and autologous hematopoietic cell transplant were associated with a 3.4- and 2.3-fold increased rate of KC, respectively. LIMITATIONS: Participant self-reporting of some data including race without skin phototype and past medical history may have impacted analysis. CONCLUSIONS: The burden of KC in CCS remains high, but predictable risk factors should guide screening.

Adenovirus infection in adult patients undergoing allogeneic hematopoietic stem cell transplant: Incidence, clinical management, and outcome.

BACKGROUND: Adenovirus infection (ADVi) is an emergent complication in adult patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is associated with poor outcome. Available data on risk factors and optimal management of ADVi in adult allo-HSCT recipients are limited, and recommendations on monitoring and pre-emptive therapy are mainly based on pediatric data. METHODS: In this single-center, retrospective study, we reported all cases of positive ADV-DNA from adult patients undergoing allo-HSCT in the period 2014-2019. The study aimed to describe the incidence of ADVi at day +180 post-transplant. Secondly to describe timing, clinical presentation, risk factors, and outcome of ADVi and to analyze the application of a screening strategy in our cohort. RESULTS: In 445 allo-HSCT recipients, the day +180 incidence was: 9% (39/445) for ADVi, 5% (24/445) for ADV viremia (ADVv), and 3% (15/445) for localized ADVi. The median time to ADVi was 65 (IQR 19; 94) days after HSCT. ADVv-related mortality was 13% (3/24), all cases occurring with blood max-ADV-DNA > 10^3 cp/mL. Independent risk factors for ADVi were diagnosis of lymphoproliferative disease (p = .011) and acute graft-versus-host-disease (p = .021). CONCLUSIONS: In our cohort, ADVi and ADVv were more frequent than previously reported. ADVv with max-ADV-DNA > 10^3 cp/mL was associated with ADV-related mortality, thus careful monitoring and early initiation of treatment are advisable.

Clinicopathologic conference: Bloodstream infection in an allogeneic hamatopoietic cell transplant: Thinking beyond the usual.

This case involves a 53-year-old female with concurrent acute myeloid leukemia (AML) and multiple myeloma. She underwent cytarabine and daunorubicin (7+3) induction chemotherapy followed by cytarabine (HiDAC) consolidation, with an early AML relapse requiring azacitidine and venetoclax therapy. She achieved complete remission and incomplete count recovery. Following fludarabine, melphalan, and thymoglobulin induction chemotherapy, she underwent an allogeneic stem cell transplant with failure to engraft, requiring autologous stem cell rescue, buffy coat, and granulocyte transfusions, eventually presenting with a diffuse skin rash consistent with Steven-Johnson syndrome and toxic epidermal necrolysis, persistent neutropenic fevers and positive blood cultures.

Yield of repeat blood cultures in acute myeloid leukemia patients with febrile neutropenia and bacteremia following allogeneic hematopoietic stem cell transplant.

INTRODUCTION: This study explored the efficacy of repeat blood cultures in bacteremic acute myeloid leukemia (AML) patients following allogeneic hematopoietic stem cell transplantation (HSCT). METHODS: This was a retrospective study of AML patients who experienced febrile neutropenia (FN) and bacteremia following HSCT at the Taussig Cancer Center from January 1, 2019, to December 31, 2022. The primary endpoint was the rate of positive repeat blood cultures following initial positive blood culture. RESULTS: Fifty patients were included in the study. There were 50 occurrences of FN with positive initial blood cultures that were diagnosed following HSCT. Fifty initial sets of blood cultures and 96 sets of repeat blood cultures were drawn between the 50 occurrences of FN. Twelve of 96 (12.5%) repeat blood culture sets were positive for a pathogen, which occurred over nine of 50 (18.0%) episodes of FN. Three of 96 (3.2%) repeat blood culture sets grew a pathogen that differed from the pathogen that grew in the preceding positive blood culture. CONCLUSION: Among bacteremic AML patients in the post-HSCT period, the yield of repeat blood cultures for detecting previously detected and new pathogens was low.

A call to address penicillin allergy labels in patients with hematopoietic stem cell transplants: How to avoid rash decisions.

Among patients with hematopoietic stem cell transplants, infections, particularly multidrug-resistant infections, pose a grave threat. In this setting, penicillin allergy labels are both common and harmful. Though the majority of patients who report penicillin allergy can actually tolerate penicillin, penicillin allergy labels are associated with use of alternative antibiotics, which are often more broad spectrum, less effective, and more toxic. In turn, they are associated with more severe infections, multidrug-resistant infections, Clostridium difficile, and increased mortality. Evaluating penicillin allergy labels can immediately expand access to preferred therapeutic options, which are critical to care in patients with recent hematopoietic stem cell transplants. Point-of-care assessment and clinical decision tools now exist to aid the nonallergist in assessment of penicillin allergy. This can aid in expanding use of other beta-lactam antibiotics and assist in risk-stratifying patients to determine a testing strategy. In patients with low-risk reaction histories, direct oral challenges can be employed to efficiently delabel patients across clinical care settings. We advocate for multidisciplinary efforts to evaluate patients with penicillin allergy labels prior to transplantation.