Velociraptor: Cross-Platform Quantitative Search Using Hallmark Cell Features

A key challenge for single cell discovery analysis is to identify new cell types, describe them quantitatively, and seek these novel cells in new studies often using a different platform. Over the last decade, tools were developed to address identification and quantitative description of cells in human tissues and tumors. However, automated validation of populations at the single cell level has struggled due to the cytometry field's reliance on hierarchical, ordered use of features and on platform-specific rules for data processing and analysis. Here we present Velociraptor, a workflow that implements Marker Enrichment Modeling in three cross-platform modules: 1) identification of cells specific to disease states, 2) description of hallmark features for each cell and population, and 3) searching for cells matching one or more hallmark feature sets in a new dataset. A key advance is that Velociraptor registers cells between datasets, including between flow cytometry and quantitative imaging using different, overlapping feature sets. Four datasets were used to challenge Velociraptor and reveal new biological insights. Working at the individual sample level, Velociraptor tracked the abundance of clinically significant glioblastoma brain tumor cell subsets and characterized the cells that predominate in recurrent tumors as a close match for rare, negative prognostic cells originally observed in matched pre-treatment tumors. In patients with inborn errors of immunity, Velociraptor identified genotype-specific cells associated with GATA2 haploinsufficiency. Finally, in cross-platform analysis of immune cells in multiplex imaging of breast cancer, Velociraptor sought and correctly identified memory T cell subsets in tumors. Different phenotypic descriptions generated by algorithms or humans were shown to be effective as search inputs, indicating that cell identity need not be described in terms of per-feature cutoffs or strict hierarchical analyses. Velociraptor thus identifies cells based on hallmark feature sets, such as protein expression signatures, and works effectively with data from multiple sources, including suspension flow cytometry, imaging, and search text based on known or theoretical cell features.

An International Learning Collaborative Phase 2 Trial for Haploidentical Bone Marrow Transplant in Sickle Cell Disease

In the setting of a learning collaborative, we conducted an international multicenter phase 2 clinical trial testing the hypothesis that non-myeloablative related haploidentical BMT with thiotepa and post-transplant cyclophosphamide (PTCy) will result in 2-year event-free survival (no graft failure or death) of at least 80%. A total of 70 participants (median age 19.1 (IQR 14.1 - 25.0) were evaluable based on the conditioning protocol. Graft failure occurred in 11.4% (8/70) and only in participants <18 years (p=0.001); all had autologous reconstitution. After a median follow-up of 2.4 years (IQR 1.5-3.9), the 2-year Kaplan-Meier-based probability of event-free survival was 82.6% (95% CI 71.4%-89.7%). The 2-year overall survival was 94.1% (95% CI 84.9%-97.7%) with no difference between the child and adult participants (p=0.889). After excluding participants with graft failure (n=8), participants with engraftment had median whole blood donor chimerism values at D+180 and D+365 post-transplant of 100.0% (IQR 99.8 - 100.0%; n=59) and 100.0% (IQR 100.0 - 100.0%; n=58), respectively, and 96.6% (57/59) were off immunosuppression at 1-year post-transplant. The 1-year grades III-IV acute graft versus host disease (GvHD) rate was 10.0% (95% CI 4.6 - 18.6%), and the 2-year moderate-severe chronic GvHD rate was 10.0% (95% CI 4.6 - 18.6%). Five participants (7.1%) died from infectious complications. We demonstrate that non-myeloablative haploidentical BMT with thiotepa and PTCy is a readily available curative therapy for most adults, even those with organ damage, instead of the more expensive myeloablative gene therapy and gene editing. Additional strategies are required for children to decrease graft failure rates (ClinicalTrials.gov identifier NCT01850108).

Alemtuzumab and CXCL9 levels predict likelihood of sustained engraftment after reduced intensity conditioning HCT

Overall survival following reduced intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (HCT) using alemtuzumab, fludarabine, and melphalan is favorable in patients transplanted for inborn errors of immunity (IEI), but RIC is associated with high rates of mixed chimerism (MC) and secondary graft failure (GF). We hypothesized that peri-transplant alemtuzumab levels or specific patterns of inflammation would predict these risks. We assessed samples from BMT CTN 1204 (NCT01998633) to study the impact of alemtuzumab levels and cytokine patterns on MC and impending or established secondary GF (defined as donor chimerism <5% after initial engraftment and/or requirement of cellular intervention). Thirty-three patients with HLH (n=25) and other IEI (n=8) who underwent HCT with T-cell replete grafts were included. Patients with day 0 alemtuzumab levels ≤0.32μg/mL had a markedly lower incidence of MC, 14.3%, versus 90.9% in patients >0.32μg/mL (p=0.008). Impending or established secondary GF was only observed in patients with day 0 alemtuzumab levels >0.32µg/mL (p=0.08). Unexpectedly, patients with impending or established secondary GF had lower CXCL9 levels. The cumulative incidence of impending or established secondary GF in patients with a day +14 CXCL9 level ≤2394pg/mL (day +14 median) was 73.6% versus 0% in patients >2394pg/mL (p=0.002). CXCL9 levels inversely correlated with alemtuzumab levels. These findings support a relationship between alemtuzumab levels, CXCL9 levels, and sustained engraftment. These data suggest a model in which higher levels of alemtuzumab at day 0 deplete donor T-cells, inhibit the graft-versus-marrow reaction (thereby suppressing CXCL9 levels), and adversely impact sustained engraftment in the non-myeloablative HCT setting. Clinical Trial # NCT01998633.

Applying a risk prediction model for bloodstream infection in a febrile, nonseverely neutropenic cohort of pediatric stem cell transplant patients

BACKGROUND

The optimal management of febrile stem cell transplant (SCT) patients presenting without severe neutropenia (absolute neutrophil count [ANC] ≥ 500/µL) is unclear. The authors have developed iterative risk prediction models (Esbenshade Vanderbilt [EsVan] models) that reliably predict bloodstream infections (BSIs) in the febrile general pediatric oncology population without severe neutropenia, but SCT-specific data are limited.

METHODS

All SCTs occurring from May 2005 to November 2019 at a single institution were identified. Episodes of fever with a central venous catheter and ANC values ≥ 500/µL were abstracted. All previous versions of the EsVan model were applied to the SCT data, and c-statistics were generated. The models were additionally applied to each type of transplant (autologous/allogeneic), and a new allogeneic model that further adjusted for metrics of immunosuppression, Esbenshade Vanderbilt Allogeneic SCT Model (EsVanAlloSCT), was developed and internally validated.

RESULTS

For 429 SCT episodes (221 autologous and 208 allogeneic), the BSI incidence was 19.6% (84 of 429), and it was higher in allogeneic transplant patients (25.5%) than autologous transplant patients (14.0%; p < .01). All versions of the EsVan model performed well for the overall SCT cohort (c-statistics, 0.759-0.795). The EsVan models performed better for the autologous episodes (c-statistics, 0.869-0.881) than the allogeneic SCT episodes (c-statistics, 0.678-0.717). The new allogeneic transplant-specific model, EsVanAlloSCT, which added an adjustment for the extent of immunosuppression, yielded a c-statistic of 0.792 (bootstrap-corrected, 0.750).

CONCLUSIONS

The EsVan models work exceptionally well when they are applied to autologous SCT, but they work less well for allogeneic SCT. EsVanAlloSCT appears to improve the predictive ability in allogeneic SCT, but it will need additional external validation.

A Diagnostic Prediction Model to Distinguish Multisystem Inflammatory Syndrome in Children

OBJECTIVE

Features of multisystem inflammatory syndrome in children (MIS-C) overlap with other syndromes, making the diagnosis difficult for clinicians. We aimed to compare clinical differences between patients with and without clinical MIS-C diagnosis and develop a diagnostic prediction model to assist clinicians in identification of patients with MIS-C within the first 24 hours of hospital presentation.

METHODS

A cohort of 127 patients (<21 years) were admitted to an academic children's hospital and evaluated for MIS-C. The primary outcome measure was MIS-C diagnosis at Vanderbilt University Medical Center. Clinical, laboratory, and cardiac features were extracted from the medical record, compared among groups, and selected a priori to identify candidate predictors. Final predictors were identified through a logistic regression model with bootstrapped backward selection in which only variables selected in more than 80% of 500 bootstraps were included in the final model.

RESULTS

Of 127 children admitted to our hospital with concern for MIS-C, 45 were clinically diagnosed with MIS-C and 82 were diagnosed with alternative diagnoses. We found a model with four variables-the presence of hypotension and/or fluid resuscitation, abdominal pain, new rash, and the value of serum sodium-showed excellent discrimination (concordance index 0.91; 95% confidence interval: 0.85-0.96) and good calibration in identifying patients with MIS-C.

CONCLUSION

A diagnostic prediction model with early clinical and laboratory features shows excellent discrimination and may assist clinicians in distinguishing patients with MIS-C. This model will require external and prospective validation prior to widespread use.

Disease Progression of WHIM Syndrome in an International Cohort of 66 Pediatric and Adult Patients

Warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome (WS) is a combined immunodeficiency caused by gain-of-function mutations in the C-X-C chemokine receptor type 4 (CXCR4) gene. We characterize a unique international cohort of 66 patients, including 57 (86%) cases previously unreported, with variable clinical phenotypes. Of 17 distinct CXCR4 genetic variants within our cohort, 11 were novel pathogenic variants affecting 15 individuals (23%). All variants affect the same CXCR4 region and impair CXCR4 internalization resulting in hyperactive signaling. The median age of diagnosis in our cohort (5.5 years) indicates WHIM syndrome can commonly present in childhood, although some patients are not diagnosed until adulthood. The prevalence and mean age of recognition and/or onset of clinical manifestations within our cohort were infections 88%/1.6 years, neutropenia 98%/3.8 years, lymphopenia 88%/5.0 years, and warts 40%/12.1 years. However, we report greater prevalence and variety of autoimmune complications of WHIM syndrome (21.2%) than reported previously. Patients with versus without family history of WHIM syndrome were diagnosed earlier (22%, average age 1.3 years versus 78%, average age 5 years, respectively). Patients with a family history of WHIM syndrome also received earlier treatment, experienced less hospitalization, and had less end-organ damage. This observation reinforces previous reports that early treatment for WHIM syndrome improves outcomes. Only one patient died; death was attributed to complications of hematopoietic stem cell transplantation. The variable expressivity of WHIM syndrome in pediatric patients delays their diagnosis and therapy. Early-onset bacterial infections with severe neutropenia and/or lymphopenia should prompt genetic testing for WHIM syndrome, even in the absence of warts.

Irradiation-free, T-cell replete haploidentical transplant for Fanconi anaemia, weighing the benefits

The optimal haploidentical haematopoietic cell transplant approach for Fanconi anaemia (FA) patients is not well established, given the rarity of the disease, the increased sensitivity to DNA-damaging agents and the high risk of severe graft-versus-host disease (GVHD). The report by Xu et al. suggests that excellent engraftment and short-term survival can be achieved in FA patients without irradiation, but their retrospective cohort was plagued by a high rate of severe GVHD. Our commentary explores the outcomes in T-cell replete haploidentical haematopoietic cell transplant and ponders whether elimination of total body irradiation in FA patients is the best method if it limits the ability to safely administer post-transplant cyclophosphamide.

Systems Immunology Analyses of STAT1 Gain-of-Function Immune Phenotypes Reveal Heterogeneous Response to IL-6 and Broad Immunometabolic Roles for STAT1

Patients with STAT1 gain-of-function (GOF) pathogenic variants have enhanced or prolonged STAT1 phosphorylation following cytokine stimulation and exhibit increased yet heterogeneous susceptibility to infections, autoimmunity, and cancer. Although disease phenotypes are diverse and other genetic factors contribute, how STAT1 GOF affects cytokine sensitivity and cell biology remains poorly defined. In this study, we analyzed the immune and immunometabolic profiles of two patients with known pathogenic heterozygous STAT1 GOF mutation variants. A systems immunology approach of peripheral blood cells from these patients revealed major changes in multiple immune cell compartments relative to healthy adult and pediatric donors. Although many phenotypes of STAT1 GOF donors were shared, including increased Th1 cells but decreased class-switched B cells and plasmacytoid dendritic cell populations, others were heterogeneous. Mechanistically, hypersensitivity for cytokine-induced STAT1 phosphorylation in memory T cell populations was particularly evident in response to IL-6 in one STAT1 GOF patient. Immune cell metabolism directly influences cell function, and the STAT1 GOF patients shared an immunometabolic phenotype of heightened glucose transporter 1 (GLUT1) and carnitine palmitoyl transferase 1A (CPT1a) expression across multiple immune cell lineages. Interestingly, the metabolic phenotypes of the pediatric STAT1 GOF donors more closely resembled or exceeded those of healthy adult than healthy age-similar pediatric donors, which had low expression of these metabolic markers. These results define new features of STAT1 GOF patients, including a differential hypersensitivity for IL-6 and a shared increase in markers of metabolism in many immune cell types that suggests a role for STAT1 in metabolic regulation of immunity.

Diagnosis and therapeutic decision-making for the neutropenic patient

Determining the cause of a low neutrophil count in a pediatric or adult patient is essential for the hematologist's clinical decision-making. Fundamental to this diagnostic process is establishing the presence or lack of a mature neutrophil storage pool, as absence places the patient at higher risk for infection and the need for supportive care measures. Many diagnostic tests, eg, a peripheral blood smear and bone marrow biopsy, remain important tools, but greater understanding of the diversity of neutropenic disorders has added new emphasis on evaluating for immune disorders and genetic testing. In this article, a structure is provided to assess patients based on the mechanism of neutropenia and to prioritize testing based on patient age and hypothesized pathophysiology. Common medical quandaries including fever management, need for growth factor support, risk of malignant transformation, and curative options in congenital neutropenia are reviewed to guide medical decision-making in neutropenic patients.

484. Identification of Early Features to Differentiate Hospitalized Children Admitted for Suspected MIS-C from Alternative Diagnoses

Background

Multi-system inflammatory syndrome in children (MIS-C) is a rare consequence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). MIS-C shares features with common infectious and inflammatory syndromes and differentiation early in the course is difficult. Identification of early features specific to MIS-C may lead to faster diagnosis and treatment. We aimed to determine clinical, laboratory, and cardiac features distinguishing MIS-C patients within the first 24 hours of admission to the hospital from those who present with similar features but ultimately diagnosed with an alternative etiology.

Methods

We performed retrospective chart reviews of children (0-20 years) who were admitted to Vanderbilt Children’s Hospital and evaluated under our institutional MIS-C algorithm between June 10, 2020-April 8, 2021. Subjects were identified by review of infectious disease (ID) consults during the study period as all children with possible MIS-C require an ID consult per our institutional algorithm. Clinical, lab, and cardiac characteristics were compared between children with and without MIS-C. The diagnosis of MIS-C was determined by the treating team and available consultants. P-values were calculated using two-sample t-tests allowing unequal variances for continuous and Pearson’s chi-squared test for categorical variables, alpha set at < 0.05.

Results

There were 128 children admitted with concern for MIS-C. Of these, 45 (35.2%) were diagnosed with MIS-C and 83 (64.8%) were not. Patients with MIS-C had significantly higher rates of SARS-CoV-2 exposure, hypotension, conjunctival injection, abdominal pain, and abnormal cardiac exam (Table 1). Laboratory evaluation showed that patients with MIS-C had lower platelet count, lymphocyte count and sodium level, with higher c-reactive protein, fibrinogen, B-type natriuretic peptide, and neutrophil percentage (Table 2). Patients with MIS-C also had lower ejection fraction and were more likely to have abnormal electrocardiogram.

Conclusion

We identified early features that differed between patients with MIS-C from those without. Development of a diagnostic prediction model based on these early distinguishing features is currently in progress.

Disclosures

Natasha B. Halasa, MD, MPH, Genentech (Other Financial or Material Support, I receive an honorarium for lectures - it’s a education grant, supported by genetech)Quidel (Grant/Research Support, Other Financial or Material Support, Donation of supplies/kits)Sanofi (Grant/Research Support, Other Financial or Material Support, HAI/NAI testing) Natasha B. Halasa, MD, MPH, Genentech (Individual(s) Involved: Self): I receive an honorarium for lectures - it’s a education grant, supported by genetech, Other Financial or Material Support, Other Financial or Material Support; Sanofi (Individual(s) Involved: Self): Grant/Research Support, Research Grant or Support James A. Connelly, MD, Horizon Therapeutics (Advisor or Review Panel member)X4 Pharmaceuticals (Advisor or Review Panel member)

Immunogenicity and safety of the human papillomavirus vaccine in young survivors of cancer in the USA: a single-arm, open-label, phase 2, non-inferiority trial

BACKGROUND

Young survivors of cancer are at increased risk for cancers that are related to human papillomavirus (HPV), primarily caused by oncogenic HPV types 16 and 18. We aimed to examine the immunogenicity and safety of the three-dose series of HPV vaccine in young survivors of cancer.

METHODS

We conducted an investigator-initiated, phase 2, single-arm, open-label, non-inferiority trial at five National Cancer Institute-designated comprehensive cancer centres in the USA. Eligible participants were survivors of cancer who were HPV vaccine-naive, were aged 9-26 years, in remission, and had completed cancer therapy between 1 and 5 years previously. Participants received three intramuscular doses of either quadrivalent HPV vaccine (HPV4; enrolments on or before March 1, 2016) or nonavalent HPV vaccine (HPV9; enrolments after March 1, 2016) over 6 months (on day 1, at month 2, and at month 6). We also obtained data from published clinical trials assessing safety and immunogenicity of HPV4 and HPV9 in 9-26-year-olds from the general population, as a comparator group. The primary endpoint was antibody response against HPV types 16 and 18 at month 7 in the per-protocol population. A response was deemed non-inferior if the lower bound of the multiplicity-adjusted 95% CI was greater than 0·5 for the ratio of anti-HPV-16 and anti-HPV-18 geometric mean titres (GMTs) in survivors of cancer versus the general population. Responses were examined separately in male and female participants by age group (ie, 9-15 years and 16-26 years). Safety was assessed in all participants who received at least one vaccine dose and for whom safety data were available. This study is registered with ClinicalTrials.gov, NCT01492582. This trial is now completed.

FINDINGS

Between Feb 18, 2013, and June 22, 2018, we enrolled 453 survivors of cancer, of whom 436 received one or more vaccine doses: 203 (47%) participants had survived leukaemia, 185 (42%) were female, and 280 (64%) were non-Hispanic white. Mean age at first dose was 15·6 years (SD 4·6). 378 (83%) of 453 participants had evaluable immunogenicity data; main reasons for exclusion from per-protocol analysis were to loss to follow-up, patient reasons, and medical reasons. Data were also obtained from 26 486 general population controls. The ratio of mean GMT for anti-HPV types 16 and 18 in survivors of cancer versus the general population was more than 1 for all subgroups (ie, aged 9-15 years, aged 16-26 years, male, and female groups) in both vaccine cohorts (ranging from 1·64 [95% CI 1·12-2·18] for anti-HPV type 16 in female participants aged 9-15 years who received HPV9, to 4·77 [2·48-7·18] for anti-HPV type 18 in male participants aged 16-26 years who received HPV4). Non-inferiority criteria were met within each age and sex subgroup, except against HPV type 18 in female participants aged 16-26 years receiving HPV9 (4·30 [0·00-9·05]). Adverse events were reported by 237 (54%) of 435 participants; injection site pain was most common (174 [40%] participants). One serious adverse event (ie, erythema nodosum) was possibly related to vaccine (HPV9; 16-26 year female cohort).

INTERPRETATION

Immunogenicity and safety of HPV vaccine three-dose series in survivors of cancer is similar to that in the general population, providing evidence for use in this clinically vulnerable population.

FUNDING

US National Cancer Institute, Merck, Sharp & Dohme, and American Lebanese Syrian Associated Charities.

Immunodeficiency and bone marrow failure with mosaic and germline TLR8 gain of function

Inborn errors of immunity (IEI) are a genetically heterogeneous group of disorders with a broad clinical spectrum. Identification of molecular and functional bases of these disorders is important for diagnosis, treatment, and an understanding of the human immune response. We identified 6 unrelated males with neutropenia, infections, lymphoproliferation, humoral immune defects, and in some cases bone marrow failure associated with 3 different variants in the X-linked gene TLR8, encoding the endosomal Toll-like receptor 8 (TLR8). Interestingly, 5 patients had somatic variants in TLR8 with <30% mosaicism, suggesting a dominant mechanism responsible for the clinical phenotype. Mosaicism was also detected in skin-derived fibroblasts in 3 patients, demonstrating that mutations were not limited to the hematopoietic compartment. All patients had refractory chronic neutropenia, and 3 patients underwent allogeneic hematopoietic cell transplantation. All variants conferred gain of function to TLR8 protein, and immune phenotyping demonstrated a proinflammatory phenotype with activated T cells and elevated serum cytokines associated with impaired B-cell maturation. Differentiation of myeloid cells from patient-derived induced pluripotent stem cells demonstrated increased responsiveness to TLR8. Together, these findings demonstrate that gain-of-function variants in TLR8 lead to a novel childhood-onset IEI with lymphoproliferation, neutropenia, infectious susceptibility, B- and T-cell defects, and in some cases, bone marrow failure. Somatic mosaicism is a prominent molecular mechanism of this new disease.

Quality of life and patient-reported outcomes in chronic severe neutropenia conditions

Quality of life (QOL) and patient-reported outcomes (PROs) assessments in immunodeficiency patients, including those with chronic severe neutropenia conditions, are imperative to determining modifiable health-related features to optimize care. We present the largest study to date of QOL in those with chronic severe neutropenia conditions with further evaluation of patient provider satisfaction and patient-reported outcome measures. Subjects completed electronic surveys assessing QOL, PROs, and patient provider satisfaction. There is a significantly negative impact of a chronic severe neutropenia disorder on QOL, fatigue, physical function, cognitive function and pain in adult patients when compared to controls. Children with a chronic neutropenia condition had comparable QOL to controls, but reported fewer depressive symptoms, improved mobility, and stronger self-reported peer relationships. Adults had worse scores for QOL, depression and fatigue when compared to children. Adult and pediatric chronic severe neutropenia patients or their caregivers felt that their medical provider was compassionate, trustworthy, and accessible. However, less than 50% of adult patients agreed their clinician had excellent expertise in white blood cell disorders. Chronic neutropenia complexly affect QOL and PROs. An analysis of these parameters allows for targeted interventions to improve patient psychosocial, physical and neurocognitive health.

Sexual behaviors and human papillomavirus vaccine non-initiation among young adult cancer survivors

BACKGROUND

Young adult cancer survivors are at risk for subsequent human papillomavirus (HPV)-related malignancies. High-risk sexual behavior increases risk for HPV acquisition; HPV vaccination protects against infection. We aimed to determine the prevalence of sexual behaviors, factors related to high-risk sexual behaviors, and the relationship between sexual behaviors and HPV vaccine non-initiation among survivors.

METHODS

Survivors at comprehensive cancer centers, aged 18-26 years and 1-5 years post-treatment, reported sexual behaviors and HPV vaccine initiation (i.e., ≥ 1 dose). Multivariable logistic regression was performed to calculate odds ratios (OR) and 95% confidence intervals (95%CI) for factors associated with high-risk sexual behaviors (age at first intercourse < 16 years, ≥ 3 lifetime sexual partners, or condom use ≤ 50% of the time) and to explore the relationship between sexual behaviors and vaccine non-initiation.

RESULTS

Of the 312 participants (48.1% female, median age at cancer diagnosis 17.2 years and at survey 20.9 years), sexual intercourse was reported by 63.1%. Of those reporting intercourse, 74.6% reported high-risk sexual behavior. Factors related to high-risk sexual behavior included currently dating/partnered (OR = 4.39, 95%CI 2.5-7.7, P < 0.001) and perceived susceptibility to HPV (OR = 1.76, 95%CI 1.3-2.5, P < 0.001). Most survivors (75.3%) reported HPV vaccine non-initiation; sexual behaviors were not associated with vaccine non-initiation (P = 0.4).

CONCLUSIONS

Many survivors participate in high-risk sexual behaviors, yet HPV vaccine initiation rates are low. Factors related to high-risk sexual behaviors can inform interventions to reduce risk for HPV acquisition among survivors.

IMPLICATIONS FOR CANCER SURVIVORS

Cancer survivors participate in sexual behaviors that increase risk for HPV acquisition and would benefit from vaccination.

Multidisciplinary Guidance Regarding the Use of Immunomodulatory Therapies for Acute Coronavirus Disease 2019 in Pediatric Patients

BACKGROUND

Immune-mediated lung injury and systemic hyperinflammation are characteristic of severe and critical coronavirus disease 2019 (COVID-19) in adults. Although the majority of severe acute respiratory syndrome coronavirus 2 infections in pediatric populations result in minimal or mild COVID-19 in the acute phase of infection, a small subset of children develop severe and even critical disease in this phase with concomitant inflammation that may benefit from immunomodulation. Therefore, guidance is needed regarding immunomodulatory therapies in the setting of acute pediatric COVID-19. This document does not provide guidance regarding the recently emergent multisystem inflammatory syndrome in children (MIS-C).

METHODS

A multidisciplinary panel of pediatric subspecialty physicians and pharmacists with expertise in infectious diseases, rheumatology, hematology/oncology, and critical care medicine was convened. Guidance statements were developed based on best available evidence and expert opinion.

RESULTS

The panel devised a framework for considering the use of immunomodulatory therapy based on an assessment of clinical disease severity and degree of multiorgan involvement combined with evidence of hyperinflammation. Additionally, the known rationale for consideration of each immunomodulatory approach and the associated risks and benefits was summarized.

CONCLUSIONS

Immunomodulatory therapy is not recommended for the majority of pediatric patients, who typically develop mild or moderate COVID-19. For children with severe or critical illness, the use of immunomodulatory agents may be beneficial. The risks and benefits of such therapies are variable and should be evaluated on a case-by-case basis with input from appropriate specialty services. When available, the panel strongly favors immunomodulatory agent use within the context of clinical trials. The framework presented herein offers an approach to decision-making regarding immunomodulatory therapy for severe or critical pediatric COVID-19 and is informed by currently available data, while awaiting results of placebo-controlled randomized clinical trials.

Neutropenia Is an Underrecognized Finding in Pediatric Primary Immunodeficiency Diseases: An Analysis of the United States Immunodeficiency Network Registry

BACKGROUND

The frequency of neutropenia in pediatric primary immunodeficiency disorders (PIDDs) is unknown and potentially underappreciated. Our study aimed to determine the overall frequency and severity of neutropenia in children diagnosed with a PIDD entered in the United States Immunodeficiency Network (USIDNET) patient registry.

PROCEDURE

Neutropenia data and demographic/clinical information from 1145 patients younger than 21 years of age was obtained from the USIDNET registry.

RESULTS

Neutropenia is more common in PIDD patients entered within the USIDNET registry than previously appreciated. There was a >10% occurrence rate of neutropenia in all broad primary immunodeficiency categories as well as in nearly all individual PIDDs. Neutropenia frequency was greater in African American pediatric PIDD patients than in white or Asian patients. The degree of neutropenia did not associate with mortality in pediatric patients with a PIDD.

CONCLUSION

Although our study did not assess the frequency of PIDD in patients presenting with neutropenia, the possibility of a primary immune disorder should be considered in patients with idiopathic neutropenia.

Patient-Level Factors Associated With Lack of Health Care Provider Recommendation for the Human Papillomavirus Vaccine Among Young Cancer Survivors

PURPOSE

Young cancer survivors are at increased risk for morbidities related to infection with the human papillomavirus (HPV), yet their HPV vaccine initiation rates remain low. Patient-/parent-reported lack of health care provider recommendation for HPV vaccination is strongly associated with vaccine noninitiation. We aimed to identify patient-level factors associated with survivor-/parent-reported lack of provider recommendation for HPV vaccination among young cancer survivors.

METHODS

Cancer survivors ages 9-26 years and 1-5 years off therapy completed a cross-sectional survey (parent-completed for survivors 9-17 years of age). Lack of health care provider HPV vaccine recommendation was the outcome of interest in a multivariable logistic regression model that included relevant patient-level sociodemographic, clinical, and vaccine-related variables.

RESULTS

Of 955 survivors, 54% were male, 66% were non-Hispanic White, and 36% had leukemia. At survey participation, survivors were an average age (± standard deviation) of 16.3 ± 4.7 years and 32.8 ± 14.7 months off therapy. Lack of provider HPV vaccine recommendation was reported by 73% (95% CI, 70% to 75%) of survivors. For the entire cohort, patient-level factors associated with lack of reported provider recommendation included perceived lack of insurance coverage for the HPV vaccine (odds ratio [OR], 4.0; 95% CI, 2.7 to 5.9; P < .001), male sex (OR, 2.8; 95% CI, 1.9 to 4.0; P < .001), and decreased parent-survivor communication regarding HPV vaccination (OR, 1.7 per unit decrease in score; 95% CI, 1.3 to 2.2; P < .001). In the sex- and age-stratified models, perceived lack of insurance coverage (all models) and male sex (age-stratified models) were also significantly associated with lack of reported provider recommendation.

CONCLUSION

We identified factors characterizing survivors at risk for not reporting receipt of a health care provider HPV vaccine recommendation. Future research is needed to develop interventions that facilitate effective provider recommendations for HPV vaccination among all young cancer survivors.

Pericardial effusion following hematopoietic stem cell transplantation in children: Incidence, risk factors, and outcomes

PCE is a complication of HSCT that has previously been described in small single-center studies. This study aimed to assess the frequency of, risk factors for, and outcomes of children with a PCE following HSCT across a large multi-center cohort. All patients ≤21 years undergoing first HSCT (1/2005-9/2015) were identified from the Pediatric Health Information System. ICD-9 codes were used to identify patients with a PCE during or following the transplant encounter. Multivariable modeling assessed risk factors for developing a PCE and assessed the impact of PCE on patient outcome. Of 10 455 included patients, 739 (7.1%) developed a PCE (median 69 days post-HSCT, interquartile range 33-165 days). PCE developed more commonly in allogeneic vs autologous HSCT recipients (9.1% vs 2.9%, P < .001). Among allogeneic HSCT recipients, independent risk factors for PCE included thrombotic microangiopathy (AHR 2.94, 95% CI 2.16-4.00), heart failure (AHR 2.07, 95% CI 1.61-2.66), PCE pre-HSCT (AHR 1.92, 95% CI 1.19-3.09), arrhythmia (AHR 1.76, 95% CI 1.44-2.16), graft-versus-host disease (AHR 1.31, 95% CI 1.05-1.62), female sex (AHR 1.28, 95% CI 1.07-1.52), and malignancy (AHR 1.28, 95% CI 1.02-1.60). Allogeneic HSCT patients with PCE demonstrated worse survival than those without PCE (5-year survival 50.8% vs 76.9%, P < .001). PCE was independently associated with mortality (AHR 1.96, 95% CI 1.62-2.37) following allogeneic HSCT and was not impacted by pericardial intervention. PCE occurs more commonly in patients following allogeneic (vs autologous) HSCT and is associated with inferior outcomes.

Hematopoietic Stem Cell Transplantation to Treat Leukodystrophies: Clinical Practice Guidelines from the Hunter's Hope Leukodystrophy Care Network

The leukodystrophies are a heterogeneous group of inherited diseases characterized by progressive demyelination of the central nervous system leading to devastating neurologic symptoms and premature death. Hematopoietic stem cell transplantation (HSCT) has been successfully used to treat certain leukodystrophies, including adrenoleukodystrophy, globoid leukodystrophy (Krabbe disease), and metachromatic leukodystrophy, over the past 30 years. To date, these complex patients have primarily been transplanted at a limited number of pediatric centers. As the number of cases identified through pregnancy and newborn screening is increasing, additional centers will be required to treat these children. Hunter's Hope created the Leukodystrophy Care Network in part to create and standardize high-quality clinical practice guidelines to guide the care of affected patients. In this report the clinical guidelines for the care of pediatric patients with leukodystrophies undergoing treatment with HSCT are presented. The initial transplant evaluation, determination of patient eligibility, donor selection, conditioning, supportive care, and post-transplant follow-up are discussed. Throughout these guidelines the need for early detection and treatment and the role of the partnership between families and multidisciplinary providers are emphasized.

Impact of IgG Monitoring and IVIG Supplementation on the Frequency of Febrile Illnesses in Pediatric Acute Lymphoblastic Leukemia Patients Undergoing Maintenance Chemotherapy

Monitoring serum immunoglobulin G (IgG) levels in pediatric oncology patients and treating subtherapeutic levels with intravenous immunoglobulin (IVIG) may prevent infections; however, evidence is limited. This retrospective study assessed pediatric acute lymphoblastic leukemia patients diagnosed 2006 to 2011 to evaluate if monitoring/supplementing IgG would reduce febrile illnesses during maintenance chemotherapy. A subject was categorized as "ever IgG monitored" if they had ≥1 IgG levels checked and their risk days were stratified into not IgG monitored days and IgG monitored days. IgG monitored days were further stratified into IgG monitored with IVIG supplementation, monitored with no IVIG supplementation (IgG level >500 mg/dL) and monitored with no IVIG supplementation days (IgG level <500 mg/dL). Generalized linear mixed effects poisson models were used to compare events (febrile episode, positive blood culture, and febrile upper respiratory infection rates among these groups. In 136 patients, the febrile episode rate was higher in the ever IgG monitored cohort than the never monitored cohort (5.26 vs. 3.78 episodes/1000 d). Among monitored patients, IVIG monitoring and supplementation did not significantly impact the febrile episode, febrile upper respiratory infection, or the positive blood culture rates. These data suggest that monitoring/supplementing low IgG is not indicated for infection prophylaxis in acute lymphoblastic leukemia patients during maintenance chemotherapy.

Congenital Neutropenia and Rare Functional Phagocyte Disorders in Children

Both profound neutropenia and functional phagocyte disorders render patients susceptible to recurrent, unusual, and/or life-threatening infections. Many disorders also have nonhematologic manifestations and a substantial risk of leukemogenesis. Diagnosis relies on clinical suspicion and interrogation of the complete blood count with differential/bone marrow examination coupled with immunologic and genetic analyses. Treatment of the quantitative neutrophil disorders depends on granulocyte colony-stimulating factor, whereas management of functional phagocyte disease is reliant on antimicrobials and/or targeted therapies. Hematopoietic stem cell transplant remains the only curative option for most disorders but is not used on a routine basis.

Autoimmune Enteropathy: An Updated Review with Special Focus on Stem Cell Transplant Therapy

Autoimmune enteropathy (AIE) is a complex disease affecting both children and adults. Although associated with significant morbidity and mortality, the pathophysiology of the disease and its treatment have not been well characterized. This study aims to review the medical literature available on this rare but clinically significant ailment, to help establish a better understanding of its pathophysiology and enumerate the available diagnostic and treatment modalities. A literature search was conducted on PubMed using key terms related to autoimmune enteropathy and intractable diarrhea, with no restrictions on the date of publication or language. We found a total of 98 reports of AIE published in the form of case reports and case series. The evidence reviewed suggests that AIE is a multifaceted disorder that requires a high index of suspicion in the appropriate clinical setting to be able to make an early diagnosis. Current evidence supports the use of supportive care to correct nutritional and metabolic deficiencies, and immunosuppressives and immunomodulators as directed therapies. Hematopoietic stem cell transplant is an aggressive, but successful curative modality for patients with AIE as part of immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome. Cumulative clinical experience with management of AIE has allowed improved outcomes in transplanted and non-transplanted AIE patients even though morbidity and mortality with are still high in patients with this condition. More research is needed to further define the role of new therapies for AIE, and a central registry with participation of multiple institutions might help share and standardize care of patients with this rare but serious condition.

SCID genotype and 6-month posttransplant CD4 count predict survival and immune recovery

The Primary Immune Deficiency Treatment Consortium (PIDTC) performed a retrospective analysis of 662 patients with severe combined immunodeficiency (SCID) who received a hematopoietic cell transplantation (HCT) as first-line treatment between 1982 and 2012 in 33 North American institutions. Overall survival was higher after HCT from matched-sibling donors (MSDs). Among recipients of non-MSD HCT, multivariate analysis showed that the SCID genotype strongly influenced survival and immune reconstitution. Overall survival was similar for patients with RAG, IL2RG, or JAK3 defects and was significantly better compared with patients with ADA or DCLRE1C mutations. Patients with RAG or DCLRE1C mutations had poorer immune reconstitution than other genotypes. Although survival did not correlate with the type of conditioning regimen, recipients of reduced-intensity or myeloablative conditioning had a lower incidence of treatment failure and better T- and B-cell reconstitution, but a higher risk for graft-versus-host disease, compared with those receiving no conditioning or immunosuppression only. Infection-free status and younger age at HCT were associated with improved survival. Typical SCID, leaky SCID, and Omenn syndrome had similar outcomes. Landmark analysis identified CD4+ and CD4+CD45RA+ cell counts at 6 and 12 months post-HCT as biomarkers predictive of overall survival and long-term T-cell reconstitution. Our data emphasize the need for patient-tailored treatment strategies depending upon the underlying SCID genotype. The prognostic significance of CD4+ cell counts as early as 6 months after HCT emphasizes the importance of close follow-up of immune reconstitution to identify patients who may need additional intervention to prevent poor long-term outcome.

Allogeneic Hematopoietic Cell Transplantation for Chronic Granulomatous Disease: Controversies and State of the Art

Chronic granulomatous disease (CGD) is a congenital disorder characterized by recurrent life-threatening bacterial and fungal infections and development of severe inflammation secondary to a congenital defect in 1 of the 5 phagocyte oxidase (phox) subunits of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. Hematopoietic cell transplant (HCT) is a curative treatment for patients with CGD that provides donor neutrophils with functional NADPH and superoxide anion production. Many characteristics of CGD, including preexisting infection and inflammation and the potential for cure with mixed-donor chimerism, influence the transplant approach and patient outcome. Because of the dangers of short-term death, graft-versus-host disease, and late effects from chemotherapy, HCT historically has been reserved for patients with high-risk disease and a matched donor. However, as advances in CGD and HCT treatments have evolved, recommendations on transplant eligibility also must be amended, but the development of modern guidelines has proven difficult. In this review, we provide an overview of HCT in patients with CGD, including the debate over HCT indications in them, the unique aspects of CGD that can complicate HCT, and a summary of transplant outcomes.

Identification of novel MECOM gene fusion and personalized therapeutic targets through integrative clinical sequencing in secondary acute myeloid leukemia in a patient with severe congenital neutropenia: a case report and literature review

Severe congenital neutropenia (SCN) is a rare hematologic disorder characterized by defective myelopoiesis and a high incidence of malignant transformation to myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). SCN patients who develop MDS/AML have excessive toxicities to traditional chemotherapy, and safer therapies are needed to improve overall survival in this population. In this report, we outline the use of a prospective integrative clinical sequencing trial (PEDS-MIONCOSEQ) in a patient with SCN and AML to help identify oncogenic targets for less toxic agents. Integrative sequencing identified two somatic cis-mutations in the colony stimulating factor 3 receptor (CSF3R) gene, a p.T640N mutation in the transmembrane region and a p.Q768* truncation mutation in the cytoplasmic domain. A somatic mutation p.H105Y, in the runt homology domain (RHD) of runt-related transcription factor 1 (RUNX1), was also identified. In addition, sequencing discovered a unique in-frame EIF4A2-MECOM (MDS1 and ectopic viral integration site 1 complex) chromosomal translocation with high MECOM expression. His mutations in CSF3R served as potential targets for tyrosine kinase inhibition and therefore provided an avenue to avoid more harmful therapy. This study highlights the utility of integrative clinical sequencing in SCN patients who develop leukemia and outlines a strategy on how to approach these patients in a future clinical sequencing trial to improve historically poor outcomes. A thorough review of leukemia in SCN and the role of CSF3R mutations in oncologic therapy are provided to support a new strategy on how to approach MDS/AML in SCN.

Human Papillomavirus Vaccination Rates in Young Cancer Survivors

Purpose

Cancer survivors are at high risk for human papillomavirus (HPV)-related morbidities; we estimated the prevalence of HPV vaccine initiation in cancer survivors versus the US population and examined predictors of noninitiation.

Methods

Participants included 982 cancer survivors (9 to 26 years of age; 1 to 5 years postcompletion of therapy); we assessed HPV vaccine initiation, sociodemographic and clinical characteristics, and vaccine-specific health beliefs; age-, sex-, and year-matched US population comparisons were from the National Immunization Survey-Teen and the National Health Interview Survey (2012-2015).

Results

The mean age at the time of the study was 16.3 ± 4.7 years; the mean time off therapy was 2.7 ± 1.2 years; participants were 55% male and 66% non-Hispanic white; 59% had leukemia/lymphoma. Vaccine initiation rates were significantly lower in cancer survivors versus the general population (23.8%; 95% CI, 20.6% to 27.0% v 40.5%; 95% CI, 40.2% to 40.7%; P < .001); survivors were more likely to be HPV vaccine-naïve than general population peers (odds ratio [OR], 1.72; 95% CI, 1.41 to 2.09; P < .001). Initiation in adolescent survivors (ages 13 to 17 years) was 22.0% (95% CI, 17.3% to 26.7%), significantly lower than population peers (42.5%; 95% CI, 42.2% to 42.8%; P < .001). Initiation in young adult survivors and peers (ages 18 to 26 years) was comparably low (25.3%; 95% CI, 20.9% to 29.7% v 24.2%; 95% CI, 23.6% to 24.9%). Predictors of noninitiation included lack of provider recommendation (OR, 10.8; 95% CI, 6.5 to 18.0; P < .001), survivors' perceived lack of insurance coverage for HPV vaccine (OR, 6.6; 95% CI, 3.9 to 11.0; P < .001), male sex (OR, 2.9; 95% CI, 1.7 to 4.8; P < .001), endorsement of vaccine-related barriers (OR, 2.7; 95% CI, 1.6 to 4.6; P < .001), and younger age (9 to 12 years; OR, 3.7; 95% CI, 1.8-7.6; P < .001; comparison, 13 to 17 years).

Conclusion

HPV vaccine initiation rates in cancer survivors are low. Lack of provider recommendation and barriers to vaccine receipt should be targeted in vaccine promotion efforts.

Primary immunodeficiency in the neonate: Early diagnosis and management

Many primary immunodeficiencies (PIDs) manifest in the neonatal period but can be challenging to diagnose and manage optimally. In part, the difficulty stems from the natural immaturity of the neonatal immune system that may mask immune deficits and/or complicate interpretation of clinical findings and laboratory assays. The great diversity of PIDs--from innate immune system defects to those that impact the humoral and/or cellular components of the adaptive immune system--and the rapid rate at which new PIDs are being discovered makes it challenging for practitioners to stay current. Moreover, recent appreciation for immune deficiencies that lead to autoinflammation and autoimmunity have broadened the spectrum of neonatal PID, adding additional complexity to an already intricate field. This article serves to highlight the deficiencies in the neonatal immune system, while providing a review of the more common PIDs that present in the neonate and guidelines for diagnosis and supportive care.

Integrative Clinical Sequencing in the Management of Refractory or Relapsed Cancer in Youth

IMPORTANCE

Cancer is caused by a diverse array of somatic and germline genomic aberrations. Advances in genomic sequencing technologies have improved the ability to detect these molecular aberrations with greater sensitivity. However, integrating them into clinical management in an individualized manner has proven challenging.

OBJECTIVE

To evaluate the use of integrative clinical sequencing and genetic counseling in the assessment and treatment of children and young adults with cancer.

DESIGN, SETTING, AND PARTICIPANTS

Single-site, observational, consecutive case series (May 2012-October 2014) involving 102 children and young adults (mean age, 10.6 years; median age, 11.5 years, range, 0-22 years) with relapsed, refractory, or rare cancer.

EXPOSURES

Participants underwent integrative clinical exome (tumor and germline DNA) and transcriptome (tumor RNA) sequencing and genetic counseling. Results were discussed by a precision medicine tumor board, which made recommendations to families and their physicians.

MAIN OUTCOMES AND MEASURES

Proportion of patients with potentially actionable findings, results of clinical actions based on integrative clinical sequencing, and estimated proportion of patients or their families at risk of future cancer.

RESULTS

Of the 104 screened patients, 102 enrolled with 91 (89%) having adequate tumor tissue to complete sequencing. Only the 91 patients were included in all calculations, including 28 (31%) with hematological malignancies and 63 (69%) with solid tumors. Forty-two patients (46%) had actionable findings that changed their cancer management: 15 of 28 (54%) with hematological malignancies and 27 of 63 (43%) with solid tumors. Individualized actions were taken in 23 of the 91 (25%) based on actionable integrative clinical sequencing findings, including change in treatment for 14 patients (15%) and genetic counseling for future risk for 9 patients (10%). Nine of 91 (10%) of the personalized clinical interventions resulted in ongoing partial clinical remission of 8 to 16 months or helped sustain complete clinical remission of 6 to 21 months. All 9 patients and families with actionable incidental genetic findings agreed to genetic counseling and screening.

CONCLUSIONS AND RELEVANCE

In this single-center case series involving young patients with relapsed or refractory cancer, incorporation of integrative clinical sequencing data into clinical management was feasible, revealed potentially actionable findings in 46% of patients, and was associated with change in treatment and family genetic counseling for a small proportion of patients. The lack of a control group limited assessing whether better clinical outcomes resulted from this approach than outcomes that would have occurred with standard care.

Alterations in Memory and Impact on Academic Outcomes in Children Following Allogeneic Hematopoietic Cell Transplantation

The prevalence of late effects following allogeneic hematopoietic cell transplantation (HCT), a curative treatment for pediatric leukemia, is high: 79% of HCT recipients experience chronic medical conditions. The few extant studies of cognitive late effects have focused on intelligence and are equivocal about HCT neurotoxicity. In an archival study of 30 children (mean transplant age = 6 years), we characterize neuropsychological predictors of academic outcomes. Mean intellectual and academic abilities were average, but evidenced extreme variability, particularly on measures of attention and memory: ∼25% of the sample exhibited borderline performance or lower. Medical predictors of outcome revealed paradoxically better memory associated with more severe acute graft-versus-host disease (GVHD) and associated with steroid treatment. Processing speed and memory accounted for 69% and 61% of variance in mathematics and reading outcomes, respectively. Thus, our findings revealed neurocognitive areas of vulnerability in processing speed and memory following HCT that contribute to subsequent academic difficulties.

Recurrence of Neonatal Lupus Post-Cord Blood Transplant for Severe Congenital Neutropenia

Neonatal lupus erythematosus (NLE) is a rare autoimmune disorder associated with transplacental migration of maternal autoantibodies against SS-A (Ro) or SS-B (La) antigens that results in cardiac, hepatic, cutaneous, and hematologic manifestations. Although NLE-associated neutropenia is considered transient and benign, neutropenia caused by severe congenital neutropenia (SCN) is life-threatening. Diagnosing a complicated picture of neonatal neutropenia can be challenging because there are many overlapping features between the acquired and inherited etiologies. This article highlights this diagnostic challenge with a case of delayed diagnosis of SCN due to an initial diagnosis of concurrent NLE. Secondary to SCN refractory to granulocyte colony-stimulating factor, our patient underwent a matched sibling cord blood transplant. Posttransplant, the patient developed recurrence of NLE symptoms, representing the first case of maternally transferred autoantibodies causing symptoms in a cord blood recipient. This novel finding prompted a review of the standards for collecting, processing, and storing of cord blood donations. This article also discusses the importance of physician familiarity with the differences and similarities between publicly and privately banked cord blood donations to adequately counsel expectant parents.

Reducing Treatment-Related Mortality Did Not Improve Outcomes of Allogeneic Myeloablative Hematopoietic Cell Transplantation for High-Risk Multiple Myeloma: A University of Michigan Prospective Series

Despite the ongoing advent of more effective immunomodulators and proteasome inhibitors, multiple myeloma (MM) remains incurable and no effective therapy is available for advanced aggressive disease. Although allogeneic (Allo) hematopoietic cell transplantation (HCT) has a curative potential, the outcomes remain poor because of high treatment-related mortality (TRM), mostly due to regimen-related toxicities and graft-versus-host disease (GVHD) in case of myeloablative conditionings, high relapse rate in case of reduced-intensity or nonmyeloablative regimens, and possibly other unknown MM-specific issues. In an attempt to improve TRM, without compromising conditioning intensity, we prospectively explored the feasibility and efficacy of a myeloablative but reduced-toxicity conditioning regimen, consisting of fludarabine and busulfan (FluBu4; fludarabine 40 mg/m(2)/day and busulfan 3.2 mg/kg/day i.v. × 4 days) in 22 patients with high-risk or advanced refractory MM. The majority (14 of 22, 64%) had prior autologous HCT. The median HCT-specific comorbidity index score was 3 (range, 0 to 6), with 46% having a Karnofsky performance score < 80%. Ten patients had unrelated donors, 3 of whom were 7/8 HLA-loci matched. GVHD prophylaxis was tacrolimus and methotrexate in 20 (91%). Most patients had active MM at transplantation, with a partial response in 12 of 22 (46%) and stable disease in 1 of 22 (4.5%). All 22 patients tolerated the FluBu4 conditioning well, without early toxic deaths or graft failure. Common regimen-related toxicities included mild to moderate mucositis (18 of 22, 82%) and mild transient liver function abnormality (9 of 22, 41%). There were no grade 4 toxicities but grade 3 mucositis occurred in 7 of 22 patients (32%). The cumulative incidence of severe, grades III and IV acute GVHD at day 180 was 23% (95% confidence interval [CI], 10% to 47%) and that of chronic GVHD was 68% (95% CI, 46% to 88%). The cumulative incidences of TRM at 100 days, 1 year, and 3 years were 9% (95% CI, 2% to 33%), 19% (95% CI, 7% to 44%), and 29% (95% CI, 13% to 55%), respectively. Two TRMs were due to idiopathic pneumonia syndrome and 1 was due to cirrhosis. They all had decreased pre-HCT corresponding organ function, with HCT-specific comorbidity index scores of > 3. With a median follow-up of 58.7 (range, 39 to 82) months, the cumulative incidences of relapse at 1 and 3 years were 37% (95% CI, 20% to 61%) and 50% (95% CI, 29% to 75%); those for 1-year and 3-year overall survival (OS) were 58% (95% CI, 40% to 83%) and 29% (95% CI, 15% to 57%), respectively, and those for the 1-year and 3-year progression-free survivals (PFS) were 40% (95% CI, 23% to 67%) and 15% (95% CI, 5% to 42%), respectively. In summary, the use of the myeloablative FluBu4 conditioning Allo-HCT for high-risk MM resulted in decreased TRM, compared with that of Allo-HCT using conventional myeloablative regimens; however, the relapse rate was high, including in those developing moderate-to-severe chronic GVHD. This suggested a less robust graft-versus-myeloma effect against high-risk MM, thus resulting in poor PFS and OS. Nonetheless, the FluBu4 regimen may be used as a lower-TRM platform to combine with other strategies, eg, addition of an MM-targeted agent and/or maintenance therapy with these agents, to decrease relapse or progression in patients with high-risk MM.

Strain measurement by cardiovascular magnetic resonance in pediatric cancer survivors: validation of feature tracking against harmonic phase imaging

BACKGROUND

Left ventricular strain may be a more sensitive marker of left ventricular dysfunction than ejection fraction in pediatric cancer survivors after anthracycline therapy, but there is limited validation of strain measurement by feature tracking on cardiovascular magnetic resonance (MR) images.

OBJECTIVE

To compare left ventricular circumferential and radial strain by feature tracking vs. harmonic phase imaging analysis (HARP) in pediatric cancer survivors.

MATERIALS AND METHODS

Twenty-six patients (20.2 ± 5.6 years old) underwent cardiovascular MR at least 5 years after completing anthracycline therapy. Circumferential and radial strain were measured at the base, midventricle and apex from short-axis myocardial tagged images by HARP, and from steady-state free precession images by feature tracking.

RESULTS

Left ventricular ejection fraction more closely correlated with global circumferential strain by feature tracking (r = -0.63, P = 0.0005) than by HARP (r = -0.39, P = 0.05). Midventricular circumferential strain did not significantly differ by feature tracking or HARP (-20.8 ± 3.4 vs. -19.5 ± 2.5, P = 0.07), with acceptable limits of agreement. Midventricular circumferential strain by feature tracking strongly correlated with global circumferential strain by feature tracking (r = 0.87, P < 0.0001). Radial strain by feature tracking had poor agreement with HARP, particularly at higher values of radial strain. Intraobserver and interobserver reproducibility was excellent for feature tracking circumferential strain, but reproducibility was poor for feature tracking radial strain.

CONCLUSION

Midventricular circumferential strain by feature tracking is a reliable and reproducible measure of myocardial deformation in patients status post anthracycline therapy, while radial strain measurements are unreliable. Further studies are necessary to evaluate potential relation to long-term outcomes.

Newborn screening for severe combined immunodeficiency in 11 screening programs in the United States

IMPORTANCE

Newborn screening for severe combined immunodeficiency (SCID) using assays to detect T-cell receptor excision circles (TRECs) began in Wisconsin in 2008, and SCID was added to the national recommended uniform panel for newborn screened disorders in 2010. Currently 23 states, the District of Columbia, and the Navajo Nation conduct population-wide newborn screening for SCID. The incidence of SCID is estimated at 1 in 100,000 births.

OBJECTIVES

To present data from a spectrum of SCID newborn screening programs, establish population-based incidence for SCID and other conditions with T-cell lymphopenia, and document early institution of effective treatments.

DESIGN

Epidemiological and retrospective observational study.

SETTING

Representatives in states conducting SCID newborn screening were invited to submit their SCID screening algorithms, test performance data, and deidentified clinical and laboratory information regarding infants screened and cases with nonnormal results. Infants born from the start of each participating program from January 2008 through the most recent evaluable date prior to July 2013 were included. Representatives from 10 states plus the Navajo Area Indian Health Service contributed data from 3,030,083 newborns screened with a TREC test.

MAIN OUTCOMES AND MEASURES

Infants with SCID and other diagnoses of T-cell lymphopenia were classified. Incidence and, where possible, etiologies were determined. Interventions and survival were tracked.

RESULTS

Screening detected 52 cases of typical SCID, leaky SCID, and Omenn syndrome, affecting 1 in 58,000 infants (95% CI, 1/46,000-1/80,000). Survival of SCID-affected infants through their diagnosis and immune reconstitution was 87% (45/52), 92% (45/49) for infants who received transplantation, enzyme replacement, and/or gene therapy. Additional interventions for SCID and non-SCID T-cell lymphopenia included immunoglobulin infusions, preventive antibiotics, and avoidance of live vaccines. Variations in definitions and follow-up practices influenced the rates of detection of non-SCID T-cell lymphopenia.

CONCLUSIONS AND RELEVANCE

Newborn screening in 11 programs in the United States identified SCID in 1 in 58,000 infants, with high survival. The usefulness of detection of non-SCID T-cell lymphopenias by the same screening remains to be determined.