M Carmen Suárez-Arrabal1, Cesar Mella2, Santiago M Lopez3, Nicole V Brown4, Mark W Hall5, Sue Hammond6, William Shiels7, Judith Groner8, Mario Marcon9, Octavio Ramilo10, Asuncion Mejias11. 1. Center for Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA. Electronic address: mcarmen1981@yahoo.com. 2. Center for Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA; Division of Critical Care Medicine, Nationwide Children's Hospital and The Ohio State University School of Medicine, Columbus, OH, USA. Electronic address: cfmella@texaschildrens.org. 3. Center for Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA. 4. Center for Biostatistics, The Ohio State University, Columbus, OH, USA. 5. Division of Critical Care Medicine, Nationwide Children's Hospital and The Ohio State University School of Medicine, Columbus, OH, USA. 6. Department of Pathology, Nationwide Children's Hospital and The Ohio State University School of Medicine, Columbus, OH, USA. 7. Department of Radiology, Nationwide Children's Hospital and The Ohio State University School of Medicine, Columbus, OH, USA. 8. Section of Ambulatory Pediatrics, Nationwide Children's Hospital and The Ohio State University School of Medicine, Columbus, OH, USA. 9. Department of Microbiology and Laboratory Medicine, Nationwide Children's Hospital and The Ohio State University School of Medicine, Columbus, OH, USA. 10. Center for Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA; Division of Infectious Diseases, Nationwide Children's Hospital and The Ohio State University School of Medicine, Columbus, OH, USA. 11. Center for Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA; Division of Infectious Diseases, Nationwide Children's Hospital and The Ohio State University School of Medicine, Columbus, OH, USA. Electronic address: Asuncion.Mejias@nationwidechildrens.org.
Abstract
OBJECTIVES: Animal studies suggest that RSV increases nasopharyngeal (NP) bacterial colonization facilitating bacterial infections. We investigated the influence of antibiotic treatment and colonization with potentially pathogenic bacteria on inflammatory markers and disease severity in RSV-infected in infants. METHODS: Healthy young infants hospitalized with RSV bronchiolitis (n = 136) and age-matched healthy controls (n = 23) were enrolled and NP samples cultured for potentially pathogenic bacteria including: Gram-positive bacteria (GPB): Staphylococcus aureus, Streptococcus pneumoniae, β-hemolytic Streptococcus; and Gram-negative bacteria (GNB): Moraxella catarrhalis and Haemophilus influenzae. Clinical parameters and plasma IL-8, IL-6 and TNF-α concentrations were compared according to the bacterial class and antibiotic treatment. RESULTS: Antibiotic treatment decreased by 10-fold NP bacterial recovery. Eighty-one percent of RSV infants who did not receive antibiotics before sample collection were colonized with pathogenic bacteria. Overall, GNB were identified in 21% of patients versus 4% of controls who were mostly colonized with GPB. Additionally, in RSV patients NP white blood cell counts (p = 0.026), and blood neutrophils (p = 0.02) were higher in those colonized with potentially pathogenic bacteria versus respiratory flora. RSV patients colonized with GNB had higher plasma IL-8 (p = 0.01) and IL-6 (p < 0.01) concentrations than controls, and required longer duration of oxygen (p = 0.049). CONCLUSIONS: Infants with RSV bronchiolitis colonized with potentially pathogenic bacteria had increased numbers of mucosal and systemic inflammatory cells. Specifically, colonization with GNB was associated with higher concentrations of proinflammatory cytokines and a trend towards increased disease severity.
OBJECTIVES: Animal studies suggest that RSV increases nasopharyngeal (NP) bacterial colonization facilitating bacterial infections. We investigated the influence of antibiotic treatment and colonization with potentially pathogenic bacteria on inflammatory markers and disease severity in RSV-infected in infants. METHODS: Healthy young infants hospitalized with RSV bronchiolitis (n = 136) and age-matched healthy controls (n = 23) were enrolled and NP samples cultured for potentially pathogenic bacteria including: Gram-positive bacteria (GPB): Staphylococcus aureus, Streptococcus pneumoniae, β-hemolytic Streptococcus; and Gram-negative bacteria (GNB): Moraxella catarrhalis and Haemophilus influenzae. Clinical parameters and plasma IL-8, IL-6 and TNF-α concentrations were compared according to the bacterial class and antibiotic treatment. RESULTS: Antibiotic treatment decreased by 10-fold NP bacterial recovery. Eighty-one percent of RSV infants who did not receive antibiotics before sample collection were colonized with pathogenic bacteria. Overall, GNB were identified in 21% of patients versus 4% of controls who were mostly colonized with GPB. Additionally, in RSV patients NP white blood cell counts (p = 0.026), and blood neutrophils (p = 0.02) were higher in those colonized with potentially pathogenic bacteria versus respiratory flora. RSV patients colonized with GNB had higher plasma IL-8 (p = 0.01) and IL-6 (p < 0.01) concentrations than controls, and required longer duration of oxygen (p = 0.049). CONCLUSIONS:Infants with RSV bronchiolitis colonized with potentially pathogenic bacteria had increased numbers of mucosal and systemic inflammatory cells. Specifically, colonization with GNB was associated with higher concentrations of proinflammatory cytokines and a trend towards increased disease severity.
Authors: Christian Rosas-Salazar; Meghan H Shilts; Andrey Tovchigrechko; James D Chappell; Emma K Larkin; Karen E Nelson; Martin L Moore; Larry J Anderson; Suman R Das; Tina V Hartert Journal: Am J Respir Crit Care Med Date: 2016-05-15 Impact factor: 21.405
Authors: Matthew R Hendricks; Lauren P Lashua; Douglas K Fischer; Becca A Flitter; Katherine M Eichinger; Joan E Durbin; Saumendra N Sarkar; Carolyn B Coyne; Kerry M Empey; Jennifer M Bomberger Journal: Proc Natl Acad Sci U S A Date: 2016-01-04 Impact factor: 11.205
Authors: Wouter A A de Steenhuijsen Piters; Santtu Heinonen; Raiza Hasrat; Eleonora Bunsow; Bennett Smith; Maria-Carmen Suarez-Arrabal; Damien Chaussabel; Daniel M Cohen; Elisabeth A M Sanders; Octavio Ramilo; Debby Bogaert; Asuncion Mejias Journal: Am J Respir Crit Care Med Date: 2016-11-01 Impact factor: 21.405