EBV-associated T/NK-cell lymphoproliferative disease (T/NK-LPD) is defined as

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Next-generation sequencing (NGS) has been applied in the field of infectious diseases. Bronchoalveolar lavage fluid (BALF) is considered a sterile type of specimen that is suitable for detecting pathogens of respiratory infections. The aim of this study was to comprehensively identify causative pathogens using NGS in BALF samples from immunocompetent pediatric patients with respiratory failure. Ten patients hospitalized with respiratory failure were included. BALF samples obtained in the acute phase were used to prepare DNA- and RNA-sequencing libraries. The libraries were sequenced on MiSeq, and the sequence data were analyzed using metagenome analysis tools. A mean of 2,041,216 total reads were sequenced for each library. Significant bacterial or viral sequencing reads were detected in eight of the 10 patients. Furthermore, candidate pathogens were detected in three patients in whom etiologic agents were not identified by conventional methods. The complete genome of enterovirus D68 was identified in two patients, and phylogenetic analysis suggested that both strains belong to subclade B3, which is an epidemic strain that has spread worldwide in recent years. Our results suggest that NGS can be applied for comprehensive molecular diagnostics as well as surveillance of pathogens in BALF from patients with respiratory infection.

MicroRNAs (miRNAs) are non-coding RNAs that regulate gene expression of targeted mRNAs, which are important in the pathogenesis of autoimmune diseases. MiRNAs may have the potential to serve as biomarkers of disease. We evaluated serum levels of selected miRNAs and their associations with disease activity in juvenile idiopathic arthritis (JIA). Sera and peripheral blood leukocytes were collected from patients with JIA (8 systemic onset, 16 polyarthritis) and healthy controls. Levels of miR-16, miR-132, miR-146a, miR-155, and miR-223 were quantified. Levels of miR-223 in sera were significantly higher in patients in the active phase of systemic onset JIA than in controls. MiRNAs of peripheral blood leukocytes did not exhibit any difference between patients with JIA and controls. In both systemic onset JIA and polyarthritis patients, levels of miR-223 and miR-16 correlated with erythrocyte sedimentation rate and matrix metalloproteinase-3, respectively. MiR-146a and miR-223 in polyarthritis showed correlations with matrix metalloproteinase-3. Expressions of miRNAs were altered in patients with JIA. Serum levels of miR-223 may be a potential disease biomarker. Investigation of miRNAs could be helpful in understanding the pathogenesis of JIA and could aid in the identification of additional disease biomarkers.

Background Vaccination to prevent hepatitis B (HB) virus infection is important for children undergoing immunosuppressive treatment. Information on the efficacy of HB vaccination in children with rheumatic diseases undergoing immunosuppressive therapy is scarce. Methods Children with rheumatic diseases administered HB vaccine during immunosuppressive treatment between May 2013 and September 2016 were enrolled. Patients were vaccinated three times (primary series). Those who remained seronegative after the primary series received a secondary series of vaccinations. Patient baseline characteristics and treatment details from the medical records were retrospectively investigated. The proportion of patients that was seropositive for HB virus antibody after primary‐and secondary series of vaccinations was calculated. Associations between immunosuppressants and serostatus were evaluated. Results Fifteen of 26 patients (58%) produced anti‐hepatitis B surface antibody (anti‐HBs) after the primary vaccinations. Eight of 10 patients (80%) taking methotrexate and 3 of 11 (27%) taking mycophenolate mofetil (MMF) were seropositive. Multivariate analysis adjusted for dosage of prednisolone per body weight. Multivariate analysis showed MMF was a factor impeding seroconversion (odds ratio 0.093, 95% confidence interval 0.014–0.615). In six of seven patients (86%) who received a secondary series of vaccinations, anti‐HBs were produced. Conclusions MMF may impede seroconversion after a primary series of HB vaccinations, thus requiring secondary series of vaccinations in pediatric patients with a rheumatic disease undergoing immunosuppressive therapy.