Improving diagnostic precision, care and syndrome definitions using comprehensive next-generation sequencing for the inherited bone marrow failure syndromes

Background Phenotypic overlap among the inherited bone marrow failure syndromes (IBMFSs) frequently limits the ability to establish a diagnosis based solely on clinical features. \u3e70 IBMFS genes have been identified, which often renders genetic testing prolonged and costly. Since correct diagnosis, treatment and cancer surveillance often depend on identifying the mutated gene, strategies that enable timely genotyping are essential. Methods To overcome these challenges, we developed a next-generation sequencing assay to analyse a panel of 72 known IBMFS genes. Cases fulfilling the clinical diagnostic criteria of an IBMFS but without identified causal genotypes were included. Results The assay was validated by detecting 52 variants previously found by Sanger sequencing. A total of 158 patients with unknown mutations were studied. Of 75 patients with known IBMFS categories (eg, Fanconi anaemia), 59% had causal mutations. Among 83 patients with unclassified IBMFSs, we found causal mutations and established the diagnosis in 18% of the patients. The assay detected mutant genes that had not previously been reported to be associated with the patient phenotypes. In other cases, the assay led to amendments of diagnoses. In 20% of genotype cases, the results indicated a cancer surveillance programme. Conclusions The novel assay is efficient, accurate and has a major impact on patient care

Pandemic (H1N1) 2009 influenza in Canadian pediatric cancer and hematopoietic stem cell transplant patients

Background The impact of pandemic H1N1 influenza (pH1N1) virus in pediatric cancer is uncertain. The objectives of this study were to characterize the clinical course of pH1N1 and identify factors associated with severe outcomes. Methods We conducted a Canadian multicenter retrospective review of children with cancer and stem cell transplant (SCT) recipients who were diagnosed with laboratory-confirmed pH1N1 infection between May 1, 2009 and January 31, 2010. Results We identified 100 (19 in wave 1 and 81 in wave 2) cases of pH1N1 infection. Median age was 8·7years. 71% had a hematologic malignancy, and 20% received SCT. Median duration of fever and illness was 2 and 12·5days, respectively. 51 (51·5%) were hospitalized for a median of 5days, with no deaths and only 1 requiring admission to the intensive care unit. Radiologically confirmed pneumonia was diagnosed in 10 (10%). Interruption of chemotherapy or conditioning occurred in 43 patients. In multivariable analyses, age \u3c5years (relative to ≥10years) and neutropenia were associated with hospitalization while neutropenia was associated with pneumonia. Despite oseltamivir use in 89%, viral shedding was prolonged (median, 46days) and often persisted after symptom resolution. However, an extended treatment course (\u3e5days) correlated with shortened duration of viral shedding (P=0·041). Conclusions pH1N1 infection in pediatric cancer and SCT patients infrequently caused complications but commonly interrupted cancer treatment. Persistent shedding of virus after illness resolution was common. Further research is needed to verify this finding as it could have implications for treatment guidelines and infection control practices. © 2012 Blackwell Publishing Ltd

Infectious Events Prior to Chemotherapy Initiation in Children with Acute Myeloid Leukemia

Background:The primary objective was to describe infectious complications in children with acute myeloid leukemia from presentation to the healthcare system to initiation of chemotherapy and to describe how these infections differ depending on neutropenia.Methods:We conducted a retrospective, population-based cohort study that included children and adolescents with acute myeloid leukemia diagnosed and treated at 15 Canadian centers. We evaluated infections that occurred between presentation to the healthcare system (for symptoms that led to the diagnosis of acute myeloid leukemia) until initiation of chemotherapy.Results:Among 328 children, 92 (28.0%) were neutropenic at presentation. Eleven (3.4%) had sterile-site microbiologically documented infection and four had bacteremia (only one Gram negative). Infection rate was not influenced by neutropenia. No child died from an infectious cause prior to chemotherapy initiation.Conclusion:It may be reasonable to withhold empiric antibiotics in febrile non-neutropenic children with newly diagnosed acute myeloid leukemia until initiation of chemotherapy as long as they appear well without a clinical focus of infection. Future work could examine biomarkers or a clinical score to identify children presenting with leukemia and fever who are more likely to have an invasive infection. © 2013 Portwine et al

Association between corticosteroids and infection, sepsis, and infectious death in pediatric acute myeloid leukemia (AML): Results from the Canadian infections in AML research group

Background. Infection continues to be a major problem for children with acute myeloid leukemia (AML). Objectives were to identify factors associated with infection, sepsis, and infectious deaths in children with newly diagnosed AML.Methods. We conducted a retrospective, population-based cohort study that included children ≤18 years of age with de novo, non-M3 AML diagnosed between January 1995 and December 2004, treated at 15 Canadian centers. Patients were monitored for infection from initiation of AML treatment until recovery from the last cycle of chemotherapy, conditioning for hematopoietic stem cell transplantation, relapse, persistent disease, or death (whichever occurred first). Consistent trained research associates abstracted all information from each site.Results. 341 patients were included. Median age was 7.1 years (interquartile range [IQR], 2.0-13.5) and 29 (8.5%) had Down syndrome. In sum, 26 (7.6%) experienced death as a first event. There were 1277 courses of chemotherapy administered in which sterile site microbiologically documented infection occurred in 313 courses (24.5%). Sepsis and infectious death occurred in 97 (7.6%) and 16 (1.3%) courses, respectively. The median days of corticosteroid administration was 2 per course (IQR, 0-6). In multiple regression analysis, duration of corticosteroid exposure was significantly associated with more microbiologically documented sterile site infection, bacteremia, fungal infection, and sepsis. The only factor significantly associated with infectious death was days of corticosteroid exposure (odds ratio, 1.05; 95% confidence interval, 1.02-1.08; P =. 001).Conclusions. In pediatric AML, infection, sepsis, and infectious death were associated with duration of corticosteroid exposure. Corticosteroids should be avoided when possible for this population. © The Author 2012. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved

Infections in children with down syndrome and acute myeloid leukemia: A report from the Canadian infections in AML research group

Background: Children with Down syndrome (DS) are at high risk of infectious toxicity when treated with acute lymphoblastic leukemia chemotherapy protocols optimized in children without DS. Our objective was to determine if children with DS and acute myeloid leukemia (AML) have a different risk of infection when treated with chemotherapy protocols developed for children with DS compared to AML treatment protocols developed for children without DS. Methods. We conducted a retrospective, population-based cohort study that included DS children ≤ 18 years of age with de novo, non-M3 AML diagnosed between January 1995 and December 2004, and treated at 15 Canadian centers. Patients were monitored for infection from initiation of AML treatment until recovery from the last cycle of chemotherapy, conditioning for hematopoietic stem cell transplantation, relapse, persistent disease or death (whichever occurred first). Trained research associates abstracted all information from each site. Results: There were 31 children with DS included; median age was 1.7 (range 0.1-11.1) years. Eleven were treated according to a DS-specific protocol while 20 were treated with non-DS specific protocols. A total of 157 courses of chemotherapy were delivered. Microbiologically documented sterile site infection occurred in 11.9% and 14.3% of DS-specific and non-DS specific AML treatment courses respectively. Sepsis was rare and there were no infection-related deaths. In multiple regression, treatment with a DS-specific protocol was independently associated with a reduction in microbiologically documented sterile site infection (adjusted odds ratio (OR) 0.65, 95% confidence interval (CI) 0.42-0.99; P = 0.044), and clinically documented infection (adjusted OR 0.36, 95% CI 0.14-0.91; P = 0.031) but not bacteremia (adjusted OR 0.73, 95% CI 0.44-1.22; P = 0.231). Conclusions: Our study suggests that children with DS do not experience excessive infectious toxicity during treatment for AML compared to children without DS. Incorporation of DS-specific AML treatment protocols is associated with a more favorable infection profile for children with DS-AML. © 2013 Tran et al.; licensee BioMed Central Ltd

Measuring the care needs of mothers of children with cancer: development of the FIN-PED

This 2-phase study tested the Family Inventory of Needs-Pediatrics (FIN-PED), a 52-item instrument structured to include 2 subscales, the first measuring the importance of care needs and the second measuring the extent to which needs were met. In Phase I, an expert panel of 6 mothers of children with cancer rated the tool for clarity, apparent internal consistency, and content validity. All items met preset criteria for these assessments. In Phase II, 110 mothers rated the instrument for internal consistency reliability, stability over time, and internal construct validity. Both subscales achieved an estimated internal consistency of 0.94. Evidence of the instrument's stability over time was also achieved. Factor analysis resulted in 4 interpretable factors, suggesting that the tool is multidimensional