Poor outcome after hematopoietic stem cell transplantation of patients with unclassified inherited bone marrow failure syndromes.

Classification of inherited bone marrow failure syndromes (IBMFSs) according to clinical and genetic diagnoses enables proper adjustment of treatment. Unfortunately, 30% of patients enrolled in the Canadian Inherited Marrow Failure Registry (CIMFR) with features suggesting hereditability could not be classified with a specific syndromic diagnosis. We analyzed the outcome of hematopoietic stem cell transplantation (HSCT) in unclassified IBMFSs (uIBMFSs) and the factors associated with outcome. Twenty-two patients with uIBMFSs and 70 patients with classified IBMFSs underwent HSCT. Five-year overall survival of uIBMFS patients after HSCT was inferior to that of patients with classified IBMFSs (56% vs 76.5%). The outcome of patients with uIBMFS who received cord blood was significantly lower than that of patients who received other stem cell sources (14.8% vs 90.9%). Engraftment failure was higher among patients with uIBMFS who received cord blood than those who received bone marrow. None of the following factors were significantly associated with poor survival: transfusion load, transplant indication, the intensity of conditioning regimen, human leukocyte antigen-identical sibling/alternative donor. We suggest that identifying the genetic diagnosis is essential to modulate the transplant procedure including conditioning agents and stem cell sources for better outcome and the standard cord blood transplantation (CBT) should be avoided in uIBMFS.

Pediatric Benign Neutropenia: Assessing Practice Preferences in Canada.

Pediatric benign neutropenia is a self-limited condition with a benign clinical course. An approach to this condition is not well-defined in the literature. Our objective was to use a case-based survey to elucidate trends in the diagnosis and management of benign neutropenia among pediatric hematology/oncology practitioners in Canada. We received 46 completed surveys (response rate 66%). At initial presentation with fever and neutropenia, 67% of respondents recommended partial septic workup but 11% recommended no investigations. Nearly 70% recommended admission for empiric intravenous antibiotics, while 24% would discharge home without antibiotics. In a patient with fever and known neutropenia, respondents were more likely to pursue outpatient antibiotic therapy. For investigation of chronic neutropenia, most respondents (60%) do not use antineutrophil antibody testing. Common indications for bone marrow biopsy were severe infection, prolonged neutropenia, or before initiating granulocyte colony stimulating factor. Indications for granulocyte colony stimulating factor were based on severity and frequency of infection. Most respondents (84%) would not recommend antibiotic prophylaxis. Results demonstrate the considerable variability in management of benign neutropenia among pediatric hematology/oncology practitioners in Canada and highlight the need for prospective studies to establish diagnostic criteria for benign neutropenia and evaluate management of fever in this population.

Management and outcome of febrile neutropenia in admitted presumed immunocompetent patients with suspected viral illness.

Objectives: Febrile neutropenia (FN) creates concern in paediatrics due to the risk of serious bacterial infections (SBI). Protocols with empiric antibiotics designed for hematology and oncology are often applied in healthy children with FN despite lower rates of SBI in this population. This study quantifies rates of infections in presumed immunocompetent children hospitalized with suspected viral illnesses and FN. Methods: This was a retrospective chart review of healthy children admitted to the Stollery Children's Hospital between 2007 and 2017 with fever, absolute neutrophil counts < 0.5 × 109/L, and viral symptoms. Primary outcomes were the incidence of SBI and bacterial pneumonia. Results: Of 383 encounters reviewed, 96 admissions for 82 patients met inclusion criteria. Eighty-eight encounters (91.7%) were managed with empiric antibiotics. Viruses were identified in 42% of encounters. Three blood cultures were positive for coagulase-negative Staphylococcus and one for Coryneforms, all considered contaminants. There were three urinary tract infections and two pneumonias. Eighty-three per cent of patients had normalization of neutrophil counts, with a median neutropenia duration of 3.2 months. Follow-up diagnoses included chronic benign neutropenia of childhood (N = 17) and three rheumatologic/autoimmune conditions (N = 3). Conclusion: Our results support previous findings of low rates of invasive bacterial infections in healthy children with FN. With an SBI rate of 3.1% and few patients found to have any pathologic etiology for their neutropenia, prospective studies would be valuable to evaluate the need for a practice change regarding antibiotic use in low-risk patients with suspected viral-induced neutropenia.

Androgen therapy in inherited bone marrow failure syndromes: analysis from the Canadian Inherited Marrow Failure Registry.

Progressive cytopenia is a serious complication among paediatric patients with inherited bone marrow failure syndromes (IBMFS). Androgens have been used to improve blood counts in different bone marrow failure conditions. Little is known about efficacy and toxicity with new androgens (i.e., danazol) in different types of IBMFS. We identified 29 patients from the Canadian Inherited Marrow Failure Registry, who received oxymetholone or danazol. Sixteen (55%) had haematological response including patients with unclassified IBMFS (45%). Danazol showed a better toxicity profile and similar efficacy compared to oxymetholone. Androgens are an effective and safe option to ameliorate bone marrow failure in IBMFS.

Cold External Temperatures and Sickle Cell Morbidity in Children: A Retrospective Analysis.

BACKGROUND: Genetic and environmental factors affect the occurrence of vaso-occlusive crises (VOCs) in patients with sickle cell disease (SCD). Research provides inconsistent evidence on how environmental temperature affects SCD. Edmonton, Alberta, has an increasing SCD population and is the northern-most city in North America with a population of over a million. OBJECTIVE: The objective of this study was to identify whether pediatric patients with SCD experience increased morbidity in cold external temperatures. MATERIALS AND METHODS: This study was a retrospective case series. Emergency visits, phone calls, and admission data for VOC in children were recorded from July 2011 to June 2016. Temperatures were recorded and statistically analyzed using descriptive statistics, to determine the relation to VOC. RESULTS: A total of 118 patients with 257 VOC events were reviewed. When analyzing the mean, minimum, and change in temperatures at presentation, the largest percentage of VOC events occurred at mild to moderate temperatures. Temperature data at 24 and 48 hours before the presentation had similar results. When accounting for the relative frequency of extreme weather days, there are increased VOC events with temperature fluctuations >20°C. CONCLUSIONS: There was no correlation between mean and minimum temperature change. Fluctuation in temperature of >20°C was associated with increased relative VOC frequency, suggesting that large temperature variability should be avoided in SCD, but a prospective study is required to determine causality.

Syrian Refugees and Their Impact on Health Service Delivery in the Pediatric Hematology/Oncology Clinics Across Canada.

This study examined the impact of Syrian refugees on 1 area of the Canadian health care sector. We predicted that pediatric hematology clinics across Canada would see a spike in their Syrian refugee patient population in proportion to their recent migration and, as a result, an increase in perceived workload. Data on the number of refugee patients, types of diseases, and perceived workload were gathered from hematology clinics across Canada using a clinical survey (Supplemental Digital Content 1, http://links.lww.com/JPHO/A315). The results showed that Ontario had the most Syrian refugee patients, followed by the Quebec, Western Canadian, and Atlantic regions. The results also showed that perceived workload ranged from "no increase" (4 programs) to "minimal increase" <25% (1 program), "moderate increase" 25% to 75% (4 programs), and "significant increase" >75% (3 programs, 2 of which had no transfusion-dependent thalassemia patients before the immigration).

Supplemental oxygen therapy recommendations in patients with sickle cell disease during air travel: A cross-sectional survey of North American health care providers.

INTRODUCTION: Air travel may expose patients with sickle cell disease (SCD) to an increased risk of disease-related complications. Several factors are felt to contribute including prolonged hypoxia, dehydration, temperature changes, and stress. The Canadian Paediatric Society (CPS) position statement, published in 2007, recommends that SCD patients use supplemental oxygen on flights. While the National Heart, Lung and Blood Institute (NHLBI) recommend that SCD patients dress warmly, stay hydrated, and move about the cabin. Other guidelines do not make specific recommendations. METHODS: A cross-sectional online survey was circulated through the Canadian Hemoglobinopathy Association (CanHaem) and American Society of Pediatric Hematology and Oncology (ASPHO) listservs to North American health care practitioners (HCPs). Participants were asked to share their air travel recommendations for patients with SCD. Similarly, a patient survey regarding experiences with air travel was circulated through the Sickle Cell Disease Association of Canada (SCDAC) and the Sickle Cell Foundation of Alberta (SCFOA) listservs and discussion boards. RESULTS: Although air travel is perceived to be a risk factor for sickling complications, only 18% of HCPs recommend supplemental oxygen. Most HCPs advise patients to increase hydration, carry analgesics, and wear warm clothes to prevent sickling complications. The patient survey was limited by a low response rate. CONCLUSION: The majority of HCPs are not routinely recommending prophylactic oxygen to patients with SCD during air travel.

The Changing Epidemiology of Pediatric Hemoglobinopathy Patients in Northern Alberta, Canada.

BACKGROUND: Hemoglobinopathies are associated with significant morbidity and mortality. Accurate epidemiologic data reflecting the number of hemoglobinopathy patients are lacking in Canada. Immigration patterns are shifting such that regions where these diseases were rare are seeing a rapid population expansion, revealing a gap in the health care system and the need for a public health response. METHODS: To understand the epidemiology of pediatric hemoglobinopathy patients given the provincial population growth and immigration patterns, a retrospective chart review was conducted at the Stollery Children's Hospital from January 2004 to July 2014. RESULTS: A total of 88% of patients had sickle cell disease; 55% of patients were Canadian born and 63% of families originated from Africa. There was a 3.5-fold increase in patient numbers with acceleration in patient accrual over the study period and a delay in diagnosis in 70% of patients. There was a significant increase in the number of hospitalizations over the study period. Thirteen percent required at least 1 exchange transfusion, 16% received chronic transfusions, and 30% of patients developed at least 1 severe complication related to their diagnosis. CONCLUSIONS: It is imperative to demonstrate the growing hemoglobinopathy population and changing health care requirements to advocate for appropriate resources, educate health care providers, and increase awareness.

Reanalysing genomic data by normalized coverage values uncovers CNVs in bone marrow failure gene panels.

Inherited bone marrow failure syndromes (IBMFSs) are genetically heterogeneous disorders with cytopenia. Many IBMFSs also feature physical malformations and an increased risk of cancer. Point mutations can be identified in about half of patients. Copy number variation (CNVs) have been reported; however, the frequency and spectrum of CNVs are unknown. Unfortunately, current genome-wide methods have major limitations since they may miss small CNVs or may have low sensitivity due to low read depths. Herein, we aimed to determine whether reanalysis of NGS panel data by normalized coverage value could identify CNVs and characterize them. To address this aim, DNA from IBMFS patients was analyzed by a NGS panel assay of known IBMFS genes. After analysis for point mutations, heterozygous and homozygous CNVs were searched by normalized read coverage ratios and specific thresholds. Of the 258 tested patients, 91 were found to have pathogenic point variants. NGS sample data from 165 patients without pathogenic point mutations were re-analyzed for CNVs; 10 patients were found to have deletions. Diamond Blackfan anemia genes most commonly exhibited heterozygous deletions, and included RPS19, RPL11, and RPL5. A diagnosis of GATA2-related disorder was made in a patient with myelodysplastic syndrome who was found to have a heterozygous GATA2 deletion. Importantly, homozygous FANCA deletion were detected in a patient who could not be previously assigned a specific syndromic diagnosis. Lastly, we identified compound heterozygousity for deletions and pathogenic point variants in RBM8A and PARN genes. All deletions were validated by orthogonal methods. We conclude that careful analysis of normalized coverage values can detect CNVs in NGS panels and should be considered as a standard practice prior to do further investigations.

Leukotriene A4 hydrolase expression in PEL cells is regulated at the transcriptional level and leads to increased leukotriene B4 production.

Primary effusion lymphoma (PEL) is a herpesvirus-8-associated lymphoproliferative disease characterized by migration of tumor cells to serous body cavities. PEL cells originate from postgerminal center B cells and share a remarkable alteration in B cell transcription factor expression and/or activation with classical Hodgkin's disease cells. Comparative analysis of gene expression by cDNA microarray of BCBL-1 cells (PEL), L-428 (classical Hodgkin's disease), and BJAB cells revealed a subset of genes that were differentially expressed in BCBL-1 cells. Among these, four genes involved in cell migration and chemotaxis were strongly up-regulated in PEL cells: leukotriene A4 (LTA4) hydrolase (LTA4H), IL-16, thrombospondin-1 (TSP-1), and selectin-P ligand (PSGL-1). Up-regulation of LTA4H was investigated at the transcriptional level. Full-length LTA4H promoter exhibited 50% higher activity in BCBL-1 cells than in BJAB or L-428 cells. Deletion analysis of the LTA4H promoter revealed a positive cis-regulatory element active only in BCBL-1 cells in the promoter proximal region located between -76 and -40 bp. Formation of a specific DNA-protein complex in this region was confirmed by EMSA. Coculture of ionophore-stimulated primary neutrophils with BCBL-1 cells leads to an increased production of LTB4 compared with coculture with BJAB and L-428 cells as measured by enzyme immunoassay, demonstrating the functional significance of LTA4H up-regulation.