Nosocomial exposure of health care workers to a visitor with active pulmonary tuberculosis in a pediatric intensive care unit: A contact investigation.

Visitors with active tuberculosis (TB) can lead to uncontrolled introductions in health care settings, even in facilities with robust TB control programs. We report a pediatric case of TB meningitis who had an adult visitor with active pulmonary TB. We identified 96 contacts from the index case. One high-risk contact had a positive follow-up TB test with no clinical symptoms. TB control programs should incorporate the risk of TB exposure from adult visitors, especially in pediatric settings.

Adverse events associated with weekly short course isoniazid and rifapentine therapy in pediatric patients with latent tuberculosis: A chart and literature review.

BACKGROUND: Effective yet safe treatment of latent tuberculosis is important for preventing the spread of tuberculosis and the progression to active disease in pediatric patients. As of 2017, the short course combination regimen of weekly isoniazid and rifapentine (3HP) administered by directly observed therapy (DOT) has replaced 9 months of isoniazid as the standard of treatment for latent tuberculosis in pediatric patients. The literature, limited in size, has established the 3HP regimen's superior safety and adherence. METHODS: We completed a retrospective chart review (n = 22) of pediatric patients at our institution receiving the 3HP regimen via DOT between 2017 and 2019. Frequencies of selected outcomes were compared to previously published data collected in a literature review. RESULTS: In this retrospective chart review, pediatric patients ages 2-20 years receiving 3HP with DOT for latent tuberculosis experienced frequent adverse events, more severe adverse events such as anaphylaxis, and higher treatment discontinuation than that which has been previously reported in the literature. Of note, our cohort's race/ethnicity differed from the cohorts described in the literature. CONCLUSIONS: Our data suggests that the short course combination regimen for pediatric latent tuberculosis patients may have a higher adverse event rate than previously established. Although this sample size is small, this study urges further investigation of more diverse cohorts to better establish the 3HP regimen's safety and tolerability.

Commensal Candida albicans Positively Calibrates Systemic Th17 Immunological Responses.

Mucosal barriers are densely colonized by pathobiont microbes such as Candida albicans, capable of invasive disseminated infection. However, systemic infections occur infrequently in healthy individuals, suggesting that pathobiont commensalism may elicit host benefits. We show that intestinal colonization with C. albicans drives systemic expansion of fungal-specific Th17 CD4+ T cells and IL-17 responsiveness by circulating neutrophils, which synergistically protect against C. albicans invasive infection. Protection conferred by commensal C. albicans requires persistent fungal colonization and extends to other extracellular invasive pathogens such as Staphylococcus aureus. However, commensal C. albicans does not protect against intracellular influenza virus infection and exacerbates allergic airway inflammation susceptibility, indicating that positively calibrating systemic Th17 responses is not uniformly beneficial. Thus, systemic Th17 inflammation driven by CD4+ T cells responsive to tonic stimulation by commensal C. albicans improves host defense against extracellular pathogens, but with potentially harmful immunological consequences.