Postoperative Wound Infection After Primary Closure in Pediatric Dog Bite Injuries.

INTRODUCTION: Guidelines recommend three to 5 d of antibiotic prophylaxis after dog bite injury, but variation exists in clinical practice after primary closure of wounds. The purpose of this study was to analyze antibiotic duration and incidence of infection during a study period in which an institutional protocol limiting postrepair antibiotics to a maximum of 3 d was implemented. METHODS: Dog bite injuries that underwent primary closure in patients ≤18 y were retrospectively identified from 2018 to 2022 at a level 1 pediatric trauma center. Demographic and clinical data were collected. Protocol compliance and short course of antibiotics were defined as ≤3 d of antibiotics. Multivariable regression analysis for variables associated with wound infection was performed. RESULTS: 455 injuries were included for analysis. After protocol implementation, the mean antibiotic duration decreased from 6.8 to 4.4 d (P < 0.001). Postrepair follow-up data were available for 235 (51.6%) cases in the cohort. Multivariable logistic regression identified superficial wounds and anatomic injury location to be significantly associated with wound infection. Shorter antibiotic duration was not associated with increased risk of wound infection on regression analysis, and there was no difference in postoperative wound infection rate between short-course and long-course groups (7.5% versus 7.1%, P = 0.912). CONCLUSIONS: Standardization of postoperative antibiotic duration was associated with a decrease antibiotic duration without an increase in the incidence of wound infections after closure of dog bite wounds. This study highlights the feasibility of multidisciplinary standardization of pediatric trauma care across specialties and the safety of minimizing antibiotic duration after pediatric dog bite repairs.

Clinical Characteristics and Treatment Patterns of Open Hand Fractures in the Pediatric Population.

BACKGROUND: Open hand fractures are one of the most common injuries in the pediatric population. These injuries are at higher risk of infection, especially in cases of frank contamination. Several studies on adult hand fractures are available in the literature; however, pediatric open hand fractures have yet to be extensively studied. This study aimed to define pediatric open hand fracture's demographics, clinical characteristics, and treatment patterns. METHODS: Using the Protected Health Information database, pediatric patients (<18 y old) with the diagnosis of open hand fracture from June 2016 to June 2018 were extracted. Demographic, treatment, and follow-up data were collected. Clinical outcomes included readmission and postoperative infection rates. RESULTS: There were a total of 4516 patients who met the inclusion criteria; the median age was 7 years (interquartile range: 3 to 11); 60% males; 60% white. Displaced fractures occurred in 74% of patients, with the right hand (52%) and middle finger (27%) predominance. The most common mechanism of injury was a crushing injury in-between objects (56%). Associated nerve injury occurred in 78 patients (4%) and vascular injury in 43 patients (2%). Open reduction and internal fixation were performed in 30% of patients. Cephalosporins were the most commonly prescribed antibiotics (73%), followed by aminopenicillins (7%). Nine patients had complications related to surgical intervention (0.2%), and postoperative infection occurred in 44 patients (1%). CONCLUSIONS: Pediatric open hand fractures most often occur during childhood and more frequently in males. These fractures tend to be more distal and displaced; reduction and fixation are required in one-third of the cases. Despite the absence of treatment guidelines and variability, this injury exhibits low complication rates. LEVEL OF EVIDENCE: Level III, retrospective study.

Multisystem Inflammatory Syndrome in Children: Survey of Protocols for Early Hospital Evaluation and Management.

OBJECTIVE: To describe the similarities and differences in the evaluation and treatment of multisystem inflammatory syndrome in children (MIS-C) at hospitals in the US. STUDY DESIGN: We conducted a cross-sectional survey from June 16 to July 16, 2020, of US children's hospitals regarding protocols for management of patients with MIS-C. Elements included characteristics of the hospital, clinical definition of MIS-C, evaluation, treatment, and follow-up. We summarized key findings and compared results from centers in which >5 patients had been treated vs those in which ≤5 patients had been treated. RESULTS: In all, 40 centers of varying size and experience with MIS-C participated in this protocol survey. Overall, 21 of 40 centers required only 1 day of fever for MIS-C to be considered. In the evaluation of patients, there was often a tiered approach. Intravenous immunoglobulin was the most widely recommended medication to treat MIS-C (98% of centers). Corticosteroids were listed in 93% of protocols primarily for moderate or severe cases. Aspirin was commonly recommended for mild cases, whereas heparin or low molecular weight heparin were to be used primarily in severe cases. In severe cases, anakinra and vasopressors frequently were recommended; 39 of 40 centers recommended follow-up with cardiology. There were similar findings between centers in which >5 patients vs ≤5 patients had been managed. Supplemental materials containing hospital protocols are provided. CONCLUSIONS: There are many similarities yet key differences between hospital protocols for MIS-C. These findings can help healthcare providers learn from others regarding options for managing MIS-C.

The Emergence of Zoonotic Onchocerca lupi Infection in the United States--A Case-Series.

This case-series describes the 6 human infections with Onchocerca lupi, a parasite known to infect cats and dogs, that have been identified in the United States since 2013. Unlike cases reported outside the country, the American patients have not had subconjunctival nodules but have manifested more invasive disease (eg, spinal, orbital, and subdermal nodules). Diagnosis remains challenging in the absence of a serologic test. Treatment should be guided by what is done for Onchocerca volvulus as there are no data for O. lupi. Available evidence suggests that there may be transmission in southwestern United States, but the risk of transmission to humans is not known. Research is needed to better define the burden of disease in the United States and develop appropriately-targeted prevention strategies.

PREVALENCE OF ATOPIC DISORDERS AMONG PEDIATRIC PATIENTS WITH PULMONARY AND DISSEMINATED COCCIDIOIDOMYCOSIS.

Type 2 inflammatory responses are associated with worse prognosis in coccidioidomycosis. It is unclear whether patients with preexisting type 2 inflammation and atopic disorders are predisposed to disseminated coccidioidomycosis. A retrospective analysis of pediatric patients with disseminated coccidioidomycosis revealed no significant difference in the history of atopic disorders or eosinophilia as compared to those with isolated pulmonary disease. Tissue-specific type 2 responses may still play a role in coccidioidomycosis immune dysregulation, and further investigation is needed.

Treatments and Severe Outcomes for Patients Diagnosed With MIS-C at Four Children's Hospitals in the United States, March 16, 2020-March 10, 2021.

BACKGROUND: Clinical management of multisystem inflammatory syndrome in children (MIS-C) has varied over time and by medical institution. METHODS: Data on patients with MIS-C were collected from 4 children's hospitals between March 16, 2020 and March 10, 2021. Relationships between MIS-C treatments and patient demographics, clinical characteristics, and outcomes were described. Propensity score matching was utilized to assess the relative risk of outcomes dependent on early treatment with intravenous immunoglobulin (IVIG) or low-dose steroids, controlling for potential confounding variables. RESULTS: Of 233 patients diagnosed with MIS-C, the most commonly administered treatments were steroids (88.4%), aspirin (81.1%), IVIG (77.7%) and anticoagulants (71.2%). Compared with those patients without respiratory features, patients with respiratory features were less likely to receive IVIG and steroids on the same day (combination treatment) (44.1%). Controlling for confounding variables, patients receiving IVIG within 1 day of hospitalization were less likely to have hospital length of stay ≥8 days (RR = 0.53, 95% CI: 0.31-0.88). Patients receiving low-dose steroids within 1 day of hospitalization were less likely to develop ventricular dysfunction (RR = 0.45, 95% CI: 0.26-0.77), have increasingly elevated troponin levels (RR = 0.55, 95% CI: 0.40-0.75) or have hospital length of stay ≥8 days (RR = 0.46, 95% CI: 0.29-0.74). CONCLUSION: Treatments for MIS-C differed by hospital, patient characteristics and illness severity. When IVIG and low-dose steroids were administered in combination or low-dose steroids were administered alone within 1 day of hospitalization, the risk of subsequent severe outcomes was decreased.

Distinguishing Multisystem Inflammatory Syndrome in Children From COVID-19, Kawasaki Disease and Toxic Shock Syndrome.

BACKGROUND: Distinguishing multisystem inflammatory syndrome in children (MIS-C) from coronavirus disease 2019 (COVID-19), Kawasaki disease (KD), and toxic shock syndrome (TSS) can be challenging. Because clinical management of these conditions can vary, timely and accurate diagnosis is essential. METHODS: Data were collected from patients <21 years of age hospitalized with MIS-C, COVID-19, KD, and TSS in 4 major health care institutions. Patient demographics and clinical and laboratory data were compared among the 4 conditions, and a diagnostic scoring tool was developed to assist in clinical diagnosis. RESULTS: A total of 233 patients with MIS-C, 102 with COVID-19, 101 with KD, and 76 with TSS were included in the analysis. Patients with MIS-C had the highest prevalence of decreased cardiac function (38.6%), myocarditis (34.3%), pericardial effusion (38.2%), mitral regurgitation (31.8%) and pleural effusion (34.8%) compared with patients with the other conditions. Patients with MIS-C had increased peak levels of C-reactive protein and decreased platelets and lymphocyte nadir counts compared with patients with COVID-19 and KD and elevated levels of troponin, brain natriuretic peptide and pro-brain natriuretic peptide compared with COVID-19. Diagnostic scores utilizing clinical findings effectively distinguished MIS-C from COVID-19, KD, and TSS, with internal validation showing area under the curve ranging from 0.87 to 0.97. CONCLUSIONS: Compared with COVID-19, KD, and TSS, patients with MIS-C had significantly higher prevalence of cardiac complications, elevated markers of inflammation and cardiac damage, thrombocytopenia, and lymphopenia. Diagnostic scores can be a useful tool for distinguishing MIS-C from COVID-19, KD, and TSS.

Serologic and Cytokine Signatures in Children With Multisystem Inflammatory Syndrome and Coronavirus Disease 2019.

BACKGROUND: The serologic and cytokine responses of children hospitalized with multisystem inflammatory syndrome (MIS-C) vs coronavirus disease 2019 (COVID-19) are poorly understood. METHODS: We performed a prospective, multicenter, cross-sectional study of hospitalized children who met the Centers for Disease Control and Prevention case definition for MIS-C (n = 118), acute COVID-19 (n = 88), or contemporaneous healthy controls (n = 24). We measured severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike receptor-binding domain (RBD) immunoglobulin G (IgG) titers and cytokine concentrations in patients and performed multivariable analysis to determine cytokine signatures associated with MIS-C. We also measured nucleocapsid IgG and convalescent RBD IgG in subsets of patients. RESULTS: Children with MIS-C had significantly higher SARS-CoV-2 RBD IgG than children with acute COVID-19 (median, 2783 vs 146; P < .001), and titers correlated with nucleocapsid IgG. For patients with MIS-C, RBD IgG titers declined in convalescence (median, 2783 vs 1135; P = .010) in contrast to patients with COVID-19 (median, 146 vs 4795; P < .001). MIS-C was characterized by transient acute proinflammatory hypercytokinemia, including elevated levels of interleukin (IL) 6, IL-10, IL-17A, and interferon gamma (IFN-γ). Elevation of at least 3 of these cytokines was associated with significantly increased prevalence of prolonged hospitalization ≥8 days (prevalence ratio, 3.29 [95% CI, 1.17-9.23]). CONCLUSIONS: MIS-C was associated with high titers of SARS-CoV-2 RBD IgG antibodies and acute hypercytokinemia with IL-6, IL-10, IL-17A, and IFN-γ.

A decreased frequency of regulatory T cells in patients with common variable immunodeficiency.

INTRODUCTION: Common variable immunodeficiency disorder (CVID) is a heterogeneous syndrome, characterized by deficient antibody production and recurrent bacterial infections in addition abnormalities in T cells. CD4(+)CD25(high) regulatory T cells (Treg) are essential modulators of immune responses, including down-modulation of immune response to pathogens, allergens, cancer cells and self-antigens. OBJECTIVE: In this study we set out to investigate the frequency of Treg cells in CVID patients and correlate with their immune activation status. MATERIALS AND METHODS: Sixteen patients (6 males and 10 females) with CVID who had been treated with regular intravenous immunoglobulin and 14 controls were enrolled. Quantitative analyses of peripheral blood mononuclear cells (PBMC) were performed by multiparametric flow cytometry using the following cell markers: CD38, HLA-DR, CCR5 (immune activation); CD4, CD25, FOXP3, CD127, and OX40 (Treg cells); Ki-67 and IFN-gamma (intracellular cytokine). RESULTS: A significantly lower proportion of CD4(+)CD25(high)FOXP3 T cells was observed in CVID patients compared with healthy controls (P<0.05). In addition to a higher proportion of CD8(+) T cells from CVID patients expressing the activation markers, CD38(+) and HLA-DR(+) (P<0.05), we observed no significant correlation between Tregs and immune activation. CONCLUSION: Our results demonstrate that a reduction in Treg cells could have impaired immune function in CVID patients.

Elevated frequency of gamma interferon-producing NK cells in healthy adults vaccinated against influenza virus.

Recent studies indicate that innate immunity in influenza virus infection is an area of substantial importance for our understanding of influenza virus pathogenesis, yet our knowledge of the mechanisms controlling innate immunity remains limited. Further delineation of the roles of NK cells and innate immunity in viral infection may have important implications for the development of improved influenza virus vaccines. In this study, we evaluated the phenotype and function of NK and T lymphocytes, as well as influenza virus-specific immunoglobulin G production, prior to and following vaccination with the routinely administered trivalent influenza virus vaccine. We demonstrate influenza virus antigen-specific innate and adaptive cellular responses and evaluate changes in NK cell receptor expression over time. Our results demonstrate increased innate and adaptive cellular immune responses and show that NK cells are a significant source of gamma interferon (IFN-gamma) following influenza virus vaccination. An increase in the frequency of IFN-gamma-producing NK cells was observed in many subjects postvaccination. The subset distribution with respect to CD56(dim) and CD56(bright) NK cell subsets remained stable, as did the NK cell phenotype with respect to expression of cell surface activating and inhibitory receptors. These results may form the basis for further investigations of the role of NK cells in immunity to influenza.

Natural killer cells in perinatally HIV-1-infected children exhibit less degranulation compared to HIV-1-exposed uninfected children and their expression of KIR2DL3, NKG2C, and NKp46 correlates with disease severity.

NK cells play an integral role in the innate immune response by targeting virally infected and transformed cells with direct killing and providing help to adaptive responses through cytokine secretion. Whereas recent studies have focused on NK cells in HIV-1-infected adults, the role of NK cells in perinatally HIV-1-infected children is less studied. Using multiparametric flow cytometric analysis, we assessed the number, phenotype, and function of NK cell subsets in the peripheral blood of perinatally HIV-1-infected children on highly active antiretroviral therapy and compared them to perinatally exposed but uninfected children. We observed an increased frequency of NK cells expressing inhibitory killer Ig-like receptors in infected children. This difference existed despite comparable levels of total NK cells and NK cell subpopulations between the two groups. Additionally, NK cell subsets from infected children expressed, with and without stimulation, significantly lower levels of the degranulation marker CD107, which correlates with NK cell cytotoxicity. Lastly, increased expression of KIR2DL3, NKG2C, and NKp46 on NK cells correlated with decreased CD4+ T-lymphocyte percentage, an indicator of disease severity in HIV-1- infected children. Taken together, these results show that HIV-1-infected children retain a large population of cytotoxically dysfunctional NK cells relative to perinatally exposed uninfected children. This reduced function appears concurrently with distinct NK cell surface receptor expression and is associated with a loss of CD4+ T cells. This finding suggests that NK cells may have an important role in HIV-1 disease pathogenesis in HIV-1-infected children.