The Journal of infectious diseases
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Glutathione protects mice from lethal sepsis by limiting inflammation and potentiating host defense.
Neutrophils have a dual role in sepsis-defending against infection and mediating organ failure. Because glutathione (GSH) is lower in sepsis, the hypothesis that GSH depletion might impair the migratory response of neutrophils to infection was tested. ⋯ Conversely, the GSH precursor N-acetyl-l-cysteine augmented neutrophil infiltration in the peritoneum but not in the lung, decreased bacterial colonies, and improved survival. Thus, migration of neutrophils to a site of infection and to a distant site is differently regulated, and optimal GSH levels are important for an efficient response to sepsis.
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The transmission dynamics of vancomycin-resistant enterococci (VRE) and factors contributing to their dissemination are complex. Mathematical modeling was used to simulate patterns of dissemination among patients and health care workers (HCWs) and to quantify the contribution of specific factors and infection control interventions on the endemic prevalence (EP) of VRE in a long-term hemodialysis unit. The model predicted that (1) an EP of 12% would be reached over time, regardless of the number of patients initially colonized, (2) endemicity would be sustained by the constant influx of newly colonized patients discharged from the hospital, (3) duration of VRE gastrointestinal colonization would have the most impact on the number of secondary cases, increasing the EP to a maximum of 70%, and (4) decreasing the patient:HCW ratio or improving hand hygiene would decrease the EP to 3%. Decreasing the duration of colonization, limiting hospital acquisition of VRE, and improving compliance with hand hygiene in the hemodialysis unit may decrease the rapidly rising rates of VRE in the patient population.
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Chlamydia trachomatis and Neisseria gonorrhoeae are universally acknowledged as urethral pathogens, yet the etiology in the majority of cases of urethritis is unclear. Our case-control study assessed the association of Mycoplasma genitalium, Ureaplasma urealyticum, and other potential pathogens with acute nongonococcal urethritis (NGU) in heterosexual men presenting to an urban sexually transmitted diseases clinic. ⋯ U. urealyticum was not associated with NGU. By multivariate analyses, controlling for age, race, history of prior urethritis, and chlamydial infection, M. genitalium was associated with a 6.5-fold increased risk of urethritis (95% confidence interval, 2.1-19.5), which supports a role of this organism in the etiology of NGU.
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Vitamin A deficiency impairs epithelial integrity and systemic immunity and increases the incidence and severity of infections during childhood. However, findings from vitamin A supplementation trials are not consistent. Supplementation has resulted in significant reductions in mortality in several (but not all) large community-based trials among apparently healthy children. ⋯ Vitamin A supplements also reduced the severity of diarrhea in most (but not all) trials. Potential explanations for the differences in efficacy across trials are reviewed. While vitamin A supplementation is effective in reducing total mortality and complications from measles infections, it is likely to be more effective in populations suffering from nutritional deficiencies.
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The cecal ligation and puncture (CLP) model was used to investigate whether failure of neutrophil migration occurs in sepsis and whether it correlates with disease outcome. It was observed that the severity of sepsis correlates with the number of punctures in the cecum: mice with 2 punctures (sublethal [SL]-CLP) developed mild peritonitis (100% survived), whereas mice with 12 punctures (lethal [L]-CLP) developed severe peritonitis and bacteremia that evolved to sepsis (none survived). ⋯ This phenomenon was shown to be mediated by nitric oxide, because aminoguanidine prevented the failure of neutrophil migration and improved the survival of L-CLP animals. In conclusion, impairment of neutrophil migration is a crucial event in the worsening of sepsis, and nitric oxide seems to be responsible for the phenomenon.