Faculty Bibliography

Retapamulin activity against 53 isolates obtained from a mupirocin-resistant community-acquired methicillin-resistant Staphylococcus aureus pediatric disease cluster was evaluated using broth microdilution. All strains were susceptible to retapamulin with minimum inhibitory concentrations ≤ 0.5 μg/mL. DNA sequence analysis of rplC and cfr identified one rplC strain variant that did not demonstrate reduced phenotypic susceptibility to retapamulin. These results demonstrate that retapamulin may be a useful alternative therapy for mupirocin-resistant community-acquired methicillin-resistant S. aureus, especially in disease clusters.

BACKGROUND:In November 2020, the US Food and Drug Administration (FDA) provided Emergency Use Authorizations (EUA) for two novel virus-neutralizing monoclonal antibody therapies, bamlanivimab, and REGN-COV2 (casirivimab plus imdevimab), for the treatment of mild to moderate COVID-19 in adolescents and adults in specified high-risk groups. This has challenged clinicians to determine the best approach to use of these products. METHODS:A panel of experts in pediatric infectious diseases, pediatric infectious diseases pharmacy, pediatric intensive care medicine, and pediatric hematology from 29 geographically diverse North American institutions was convened. Through a series of teleconferences and web-based surveys, a guidance statement was developed and refined based on review of the best available evidence and expert opinion. RESULTS:The course of COVID-19 in children and adolescents is typically mild and there is no high-quality evidence supporting any high risk groups. There is no evidence for safety and efficacy of monoclonal antibody therapy for treatment of COVID-19 in children or adolescents, limited evidence of modest benefit in adults, and evidence for potential harm associated with infusion reactions or anaphylaxis. CONCLUSIONS:Based on evidence available as of December 20, 2020, the panel suggests against routine administration of monoclonal antibody therapy (bamlanivimab, or casirivimab and imdevimab), for treatment of COVID-19 in children or adolescents, including those designated by the FDA as at high risk of progression to hospitalization or severe disease. Clinicians and health systems choosing to use these agents on an individualized basis should consider risk factors supported by pediatric-specific evidence, and ensure implementation of a system for safe and timely administration that does not exacerbate existing healthcare disparities.

Streptococcus agalactiae (group B Streptococcus; GBS) remains a dominant cause of serious neonatal infections. One aspect of GBS that renders it particularly virulent during the perinatal period is its ability to invade the chorioamniotic membranes and persist in amniotic fluid, which is nutritionally deplete and rich in fetal immunologic factors such as antimicrobial peptides. We used next-generation sequencing of transposon-genome junctions (Tn-seq) to identify five GBS genes that promote survival in the presence of human amniotic fluid. We confirmed our Tn-seq findings using a novel CRISPR inhibition (CRISPRi) gene expression knockdown system. This analysis showed that one gene, which encodes a GntR-class transcription factor that we named MrvR, conferred a significant fitness benefit to GBS in amniotic fluid. We generated an isogenic targeted deletion of the mrvR gene, which had a growth defect in amniotic fluid relative to the wild type parent strain. The mrvR deletion strain also showed a significant biofilm defect in vitro. Subsequent in vivo studies showed that while the mutant was able to cause persistent murine vaginal colonization, pregnant mice colonized with the mrvR deletion strain did not develop preterm labor despite consistent GBS invasion of the uterus and the fetoplacental units. In contrast, pregnant mice colonized with wild type GBS consistently deliver prematurely. In a sepsis model the mrvR deletion strain showed significantly decreased lethality. In order to better understand the mechanism by which this newly identified transcription factor controls GBS virulence, we performed RNA-seq on wild type and mrvR deletion GBS strains, which revealed that the transcription factor affects expression of a wide range of genes across the GBS chromosome. Nucleotide biosynthesis and salvage pathways were highly represented among the set of differentially expressed genes, suggesting that MrvR may be involved in regulating nucleotide availability.

BACKGROUND:Although Coronavirus Disease 2019 (COVID-19) is a mild infection in most children, a small proportion develop severe or critical illness. Data evaluating agents with potential antiviral activity continue to expand, such that updated guidance is needed regarding use of these agents in children. METHODS:A panel of pediatric infectious diseases physicians and pharmacists from 20 geographically diverse North American institutions was convened. Through a series of teleconferences and web-based surveys, a set of guidance statements was developed and refined based on review of the best available evidence and expert opinion. RESULTS:Given the typically mild course of COVID-19 in children, supportive care alone is suggested for most cases. For children with severe illness, defined as a supplemental oxygen requirement without need for non-invasive or invasive mechanical ventilation or extra-corporeal membrane oxygenation (ECMO), remdesivir is suggested, preferably as part of a clinical trial if available. Remdesivir should also be considered for critically ill children requiring invasive or non-invasive mechanical ventilation or ECMO. A duration of 5 days is appropriate for most patients. The panel recommends against the use of hydroxychloroquine or lopinavir-ritonavir (or other protease inhibitors) for COVID-19 in children. CONCLUSIONS:Antiviral therapy for COVID-19 is not necessary for the great majority of pediatric patients. For children with severe or critical disease, this guidance offers an approach for decision-making regarding use of remdesivir.

Importance/UNASSIGNED:To date, no study has characterized the mucocutaneous features seen in hospitalized children with multisystem inflammatory syndrome in children (MIS-C) or the temporal association of these findings with the onset of systemic symptoms. Objective/UNASSIGNED:To describe the mucocutaneous findings seen in children with MIS-C during the height of the coronavirus disease 2019 (COVID-19) pandemic in New York City in 2020. Design, Setting, and Participants/UNASSIGNED:A retrospective case series was conducted of 35 children admitted to 2 hospitals in New York City between April 1 and July 14, 2020, who met Centers for Disease Control and Prevention and/or epidemiologic criteria for MIS-C. Main Outcomes and Measures/UNASSIGNED:Laboratory and clinical characteristics, with emphasis on mucocutaneous findings, of children who met criteria for MIS-C. The characterization of mucocutaneous features was verified by 2 board-certified pediatric dermatologists. Results/UNASSIGNED:Twenty-five children (11 girls [44%]; median age, 3 years [range, 0.7-17 years]) were identified who met definitional criteria for MIS-C; an additional 10 children (5 girls [50%]; median age, 1.7 years [range, 0.2-15 years]) were included as probable MIS-C cases (patients met all criteria with the exception of laboratory test evidence of severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] infection or known exposure). The results of polymerase chain reaction tests for SARS-CoV-2 were positive for 10 patients (29%), and the results of SARS-CoV-2 immunoglobulin G tests were positive for 19 patients (54%). Of the 35 patients, 29 (83%) exhibited mucocutaneous changes, with conjunctival injection (n = 21), palmoplantar erythema (n = 18), lip hyperemia (n = 17), periorbital erythema and edema (n = 7), strawberry tongue (n = 8), and malar erythema (n = 6) being the most common findings. Recognition of mucocutaneous findings occurred a mean of 2.7 days (range, 1-7 days) after the onset of fever. The duration of mucocutaneous findings varied from hours to days (median duration, 5 days [range, 0-11 days]). Neither the presence nor absence of mucocutaneous findings was significantly associated with overall disease severity. Conclusions and Relevance/UNASSIGNED:In this case series of hospitalized children with suspected MIS-C during the COVID-19 pandemic, a wide spectrum of mucocutaneous findings was identified. Despite their protean and transient nature, these mucocutaneous features serve as important clues in the recognition of MIS-C.

PURPOSE OF REVIEW/OBJECTIVE:Here we summarize current knowledge about multisystem inflammatory syndrome in children (MIS-C), a presumed postinfectious inflammatory condition that has emerged as an important COVID-19-associated complication, to help clinicians identify and manage cases. RECENT FINDINGS/RESULTS:Clinical presentation of MIS-C is dominated by significant inflammation. Fever, gastrointestinal symptoms, cardiac dysfunction, and hypotension are common features. Kawasaki disease-like findings are common, but epidemiologic data and recent mechanistic studies suggest that distinct inflammatory pathways mediate Kawasaki disease and MIS-C. A broad diagnostic approach is recommended, given overlapping presentations between MIS-C and many other disease processes. Current management of MIS-C is highly variable, depending on illness severity, and can range from supportive care to aggressive immune modulation. A multidisciplinary approach with early involvement of multiple pediatric subspecialists is recommended for complicated cases. SUMMARY/CONCLUSIONS:Several studies have described the clinical manifestations of MIS-C, but definitive diagnosis remains challenging. Robust information about long-term outcomes awaits further study, as do immunologic data to refine diagnostic and therapeutic strategies.