Comparison of Musculoskeletal Infections due to Nontyphoidal Salmonella Species and Staphylococcus aureus in Immunocompetent Children.

BACKGROUND: Nontyphoidal Salmonella species (NTS) rarely cause musculoskeletal infections in healthy children. Data on NTS musculoskeletal infections in healthy children are limited. No previous studies have directly compared children with NTS musculoskeletal infections with those with Staphylococcus aureus. METHODS: This was a case-control study of children 30 days-18 years old seen at Texas Children's Hospital between 2010 and 2017 with NTS musculoskeletal infections. Controls were children with S. aureus musculoskeletal infections matched on date of infection. Patients with known predisposing conditions were excluded. Demographic and clinical risk factors between the 2 groups were compared. RESULTS: From 2010 to 2017, 27 cases of NTS musculoskeletal infections were identified, 12 (46.0%) of which occurred in healthy children. The control group had 53 patients. Predictors of NTS musculoskeletal infections included exposure to reptiles [odds ratio (OR) 8.50, 95% confidence interval (CI): 11.24-58.23] and preceding gastrointestinal symptoms (OR 5.63, 95% CI: 1.45-21.89). Children with NTS musculoskeletal infections had greater odds of pelvic and/or spinal involvement than S. aureus controls (OR 5.32, 95% CI: 1.42-20.13). Complications occurred in 16.7% of NTS cases versus 32% of S. aureus controls. CONCLUSIONS: Healthy children with NTS musculoskeletal infections more frequently report reptile exposure and preceding gastrointestinal symptoms and have pelvic and spinal involvement compared with children with musculoskeletal infections due to S. aureus. NTS should be considered as a potential cause of musculoskeletal infections in children with these risk factors. In contrast to previous case reports and case series, children with NTS musculoskeletal infections had a low rate of complications.

High-dose IgG therapy mitigates bile duct-targeted inflammation and obstruction in a mouse model of biliary atresia.

BACKGROUND: A proposed etiology of biliary atresia (BA) entails a virus-induced, progressive immune-mediated injury of the biliary system. Intravenous Ig (IVIg) has demonstrated clinical benefit in several inflammatory diseases. The aim of this study was to determine the therapeutic effects of high-dose IgG treatment in the rhesus rotavirus (RRV)-induced mouse model of BA. METHODS: Newborn mice were infected with RRV, and jaundiced mice were given high-dose IgG or albumin control. Survival, histology, direct bilirubin, liver immune cell subsets, and cytokine production were analyzed. RESULTS: There was no difference in overall survival between RRV-infected groups, however high-dose IgG resulted in decreased bilirubin, bile duct inflammation, and increased extrahepatic bile duct patency. High-dose IgG decreased vascular cell adhesion molecule-1, resulting in limited migration of immune cells to portal tracts. High-dose IgG significantly decreased CD4(+) T cell production of interleukin (IL)-2, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α and CD8(+) T cell production of IFN-γ, as well as increased levels of regulatory T cells. CONCLUSION: High-dose IgG therapy in murine BA dramatically decreased Th1 cell-mediated inflammation and biliary obstruction. This study lends support for consideration of IVIg clinical trials in infants with BA, to diminish the progressive intrahepatic bile duct injury.