A distinct case of an 8-year-old female with cyclic neutropenia presenting with C. septicum abdominal sepsis and myonecrosis requiring a bowel resection and leg fasciotomy.

Clostridium septicum is a very rare cause of severe spontaneous pediatric enterocolitis and is often associated with underlying malignancy or immunocompromise. Likewise, cyclic neutropenia is a rare congenital immunodeficiency that is characterized by cyclical periods of neutropenia, often with more severe symptoms in the pediatric population. Here, we present a unique case of spontaneous C. septicum enterocolitis, sepsis, and myonecrosis in a child with undiagnosed cyclic neutropenia. Early recognition of pediatric sepsis, frequent reevaluation and identification of rapidly progressive infection, and early surgical intervention are critical for the effective management of a rare and severe infection.

Immunoglobulin VDJ repertoires reveal hallmarks of germinal centers in unique cell clusters isolated from zebrafish (Danio rerio) lymphoid tissues.

DNA mutagenesis during antibody affinity maturation has potentially oncogenic or autoimmune outcomes if not tightly controlled as it is in mammalian germinal centers. Cold blooded vertebrates lack germinal centers, yet have a functional Ig gene mutator enzyme, Aicda. In fish there are clusters of Aicda+ cells encircled by pigmented 'melano-macrophages' and we test the hypothesis that these clusters are functionally analogous to germinal centers. Sequenced IgH VDJ repertoire libraries from individual isolated clusters showed evidence of B-cell clonal expansion and VDJ somatic hypermutation. Construction of Ig clonal lineage trees revealed that unlike surrounding lymphoid tissue, each cluster is dominated by a few B-cell VDJ clonotypes having hundreds of mutated variants. Recruitment of B-cells to the clusters appears to be ongoing, as there are additional Ig clones having smaller lineages. Finally, we show evidence for positive selection for replacement mutations in regions encoding the antigen contact loops, but not in the framework regions, consistent with functional antibody modification. Melano-macrophages appear to trap the Ag used for post-mutation B-cell selection, performing a role analogous to the follicular dendritic cells of mammalian germinal centers. These findings provide insights into the evolution of the affinity maturation process, the improvement of fish vaccines and possibly also the workings of atypical ectopic germinal centers generated in several human diseases.

Comparative Usability Analysis and Parental Preferences of Three Web-Based Knowledge Translation Tools: Multimethod Study.

BACKGROUND: Connecting parents to research evidence is known to improve health decision making. However, guidance on how to develop effective knowledge translation (KT) tools that synthesize child-health evidence into a form understandable by parents is lacking. OBJECTIVE: The aim of this study was to conduct a comparative usability analysis of three Web-based KT tools to identify differences in tool effectiveness, identify which format parents prefer, and better understand what factors affect usability for parents. METHODS: We evaluated a Cochrane plain language summary (PLS), Blogshot, and a Wikipedia page on a specific child-health topic (acute otitis media). A mixed method approach was used involving a knowledge test, written usability questionnaire, and a semistructured interview. Differences in knowledge and usability questionnaire scores for each of the KT tools were analyzed using Kruskal-Wallis tests, considering a critical significance value of P=.05. Thematic analysis was used to synthesize and identify common parent preferences among the semistructured interviews. Key elements parents wanted in a KT tool were derived through author consensus using questionnaire data and parent interviews. RESULTS: In total, 16 parents (9 female) with a mean age of 39.6 (SD 11.9) years completed the study. Parents preferred the Blogshot over the PLS and Wikipedia page (P=.002) and found the Blogshot to be the most aesthetic (P=.001) and easiest to use (P=.001). Knowledge questions and usability survey data also indicated that the Blogshot was the most preferred and effective KT tool at relaying information about the topic. Four key themes were derived from thematic analysis, describing elements parents valued in KT tools. Parents wanted tools that were (1) simple, (2) quick to access and use, and (3) trustworthy, and which (4) informed how to manage the condition. Out of the three KT tools assessed, Blogshots were the most preferred tool by parents and encompassed these four key elements. CONCLUSIONS: It is important that child health evidence be available in formats accessible and understandable by parents to improve decision making, use of health care resources, and health outcomes. Further usability testing of different KT tools should be conducted involving broader populations and other conditions (eg, acute vs chronic) to generate guidelines to improve KT tools for parents.