简介：AbstractImportance:Hypervirulent variants of Klebsiella pneumoniae (hvKp) are capable of causing life-threatening pyogenic liver abscesses (PLAs), but hvKp caused PLAs was seldom reported in pediatric populations. Hence, there is an urgent need to raise our awareness of this phenomenon in pediatric populations.Objective:This study aimed to report the clinical characteristics of hvKp that caused fatal PLA complicated by bacteremia in an adolescent and further identify the microbiological and genomic features of the causative strain.Methods:A 14-year-old boy with diabetes mellitus was admitted to our hospital with a diagnosis of PLA complicated by bacteremia. A hypermucoviscous hvKp strain, KPN_19-106, was isolated from the drainage fluid present within the liver abscess cavity and blood. The hypermucoviscosity phenotype of the causative strain was determined by string test. Its virulence was measured using serum resistance assay and Galleria mellonella larvae-killing assay. Antimicrobial susceptibility was determined by broth microdilution method. Genetic information was obtained by whole-genome sequencing and bioinformatics analysis.Results:KPN_19-106 belonged to sequence type 380 and serotype K2 and exhibited stronger serum resistance and higher in vivo lethality than the well-characterized hvKp NTUH-K2044 strain. Although KPN_19-106 is susceptible to most antibiotics, no sign of improvement was observed during treatment with such drugs. Whole-genome sequencing revealed that the isolate had integrated multiple mobile genetic elements related to virulence.Interpretation:Antibiotic-susceptible hvKp can cause fatal PLA complicated by bacteremia in adolescents, with no improvement during antimicrobial therapy. The causative strain in this case had integrated multiple virulence genes and thus exhibited higher virulence both in vitro and in vivo when compared with NTUH-K2044.

简介：AbstractImportance:Acute necrotizing encephalopathy (ANE) is a rare disease with high mortality. Plasma exchange (PLEX) has recently been reported to treat ANE of childhood (ANEC), but its efficacy is uncertain.Objective:This study aimed to investigate the effectiveness of PLEX on ANEC.Methods:A retrospective study was conducted in four pediatric intensive care units from December 2014 to December 2020. All patients who were diagnosed with ANEC were included; however, these patients were excluded if their length of stay was less than 24 h. Participants were classified into PLEX and non-PLEX groups.Results:Twenty-nine patients with ANEC were identified, 10 in the PLEX group and 19 in the non-PLEX group. In the PLEX group, C-reactive protein, procalcitonin, alanine aminotransferase, and aspartate aminotransaminase levels were significantly lower after 3 days of treatment than before treatment (13.1 vs. 8.0, P = 0.043; 9.8 vs. 1.5, P = 0.028; 133.4 vs. 31.9, P = 0.028; 282.4 vs. 50.5, P = 0.046, respectively). Nine patients (31.0%, 9/29) died at discharge, and a significantly difference was found between the PLEX group and non-PLEX group [0 vs. 47.4% (9/19), P = 0.011]. The median follow-up period was 27 months, and three patients were lost to follow-up. Thirteen patients (50.0%, 13/26) died at the last follow-up, comprising three (33.3%, 3/9) in the PLEX group and ten (58.8%, 10/17) in the non-PLEX group, but there was no significant difference between the two groups (P = 0.411). Three patients (10.3%, 3/29) fully recovered.Interpretation:PLEX may reduce serum C-reactive protein and procalcitonin levels and improve liver function in the short term. PLEX may improve the prognosis of ANEC, and further studies are needed.

简介：AbstractImportance:Neuroblastoma is the most common extracranial malignant solid tumor in children. Multidisciplinary care is critical to improving the survival of pediatric patients with neuroblastoma.Objective:To systematically summarize the clinical characteristics of children with neuroblastoma and evaluate their prognosis with multidisciplinary care provided in a single center.Methods:This retrospective study analyzed the clinical data of 1041 patients with neuroblastoma who were diagnosed, treated, and followed-up in the Hematology-Oncology Center of Beijing Children’s Hospital from 2007 to 2019.Results:The median age at diagnosis was 34 months; 80.8% of the patients were younger than 5 years of age. Notably, 243 patients (23.3%) were classified as low-risk, 249 patients (23.9%) were classified as intermediate-risk, and 549 (52.7%) were classified as high-risk. Furthermore, 956 patients underwent surgical resections; 986 (94.7%) patients received chemotherapy; and 176 patients with high-risk neuroblastoma received hematopoietic stem cell transplantation. The 5-year event-free survival (EFS) rate was 91.3% and 5-year overall survival (OS) rate was 97.5% in low-risk group; in the intermediate-risk group, these rates were 85.1% and 96.7%, respectively, while they were 37.7% and 48.9% in the high-risk group (P < 0.001 for both). The 5-year EFS and OS rates were significantly higher in patients diagnosed between 2015 and 2019 than in patients diagnosed between 2007 and 2014 (P < 0.001). In total, 278 patients (26.7%) exhibited tumor relapse or progression; the median interval until relapse or progression was 14 months. Of the 233 patients who died, 83% died of relapse or progression of neuroblastoma and 4.3% died of therapy-related complications.Interpretation:The 5-year OS rate was low in high-risk patients, compared with low-and intermediate-risk patients. Multidisciplinary care is critical for improvement of survival in pediatric patients with neuroblastoma. Additional treatment strategies should be sought to improve the prognosis of patients with high-risk neuroblastoma.