Airway microbiome and responses to corticosteroids in corticosteroid-resistant asthma patients treated with acid suppression medications

Studies also report that esophageal microbiota are subject to change in health and disease, including in patients with esophagitis and GERD.2 In large population studies, the use of acid suppression drugs has been associated with the development of community-acquired pneumonia, often of Streptococcal etiology.3,4 Importantly, Streptococcus spp had been reported to be able to tolerate an acidic environment better than other microorganisms.5 To date there are a lack of studies about the contribution of GERD and acid suppressor medications on airway microbiome composition in asthma, disease severity, and response to corticosteroid treatment. [...]our study demonstrates expansion of Streptococci in the airways of CR asthmatics taking acid suppression medications. [...]the ratio of 100 bacteria per cell is likely to occur in vivo. Cellular protein extraction, RNA preparation, Western blot, and real-time PCR were performed as previously described by us.E3 1 L.A. Houghton, A.S. Lee, H. Badri, K.R. DeVault, J.A. Smith, Respiratory disease and the oesophagus: reflux, reflexes and microaspiration, Nat Rev Gastroenterol Hepatol, Vol. 13, 2016, 445-460 2 J.K. Harris, R. Fang, B.D. Wagner, H.N. Choe, C.J. Kelly, S. Schroeder, Esophageal microbiome in eosinophilic esophagitis, PLoS One, Vol. 10, 2015, e0128346 3 S.E. Gulmez, A. Holm, H. Frederiksen, T.G. Jensen, C. Pedersen, J. Hallas, Use of proton pump inhibitors and the risk of community-acquired pneumonia: a population-based case-control study, Arch Intern Med, Vol. 167, 2007, 950-955 4 R.J. Laheij, M.C. Sturkenboom, R.J. Hassing, J. Dieleman, B.H. Stricker, J.B. Jansen, Risk of community-acquired pneumonia and use of gastric acid-suppressive drugs, JAMA, Vol. 292, 2004, 1955-1960 5 R.G. Quivey Jr., W.L. Kuhnert, K. Hahn, Adaptation of oral streptococci to low pH, Adv Microb Physiol, Vol. 42, 2000, 239-274 6 E. Goleva, L.P. Jackson, J.K. Harris, C.E. Robertson, E.R. Sutherland, C.F. Hall, The effects of airway microbiome on corticosteroid responsiveness in asthma, Am J Respir Crit Care Med, Vol. 188, 2013, 1193-1201 7 D. Shahinas, C.S. Thornton, G.S. Tamber, G. Arya, A. Wong, F.B. Jamieson, Comparative genomic analyses of Streptococcus pseudopneumoniae provide insight into virulence and commensalism dynamics, PLoS One, Vol. 8, 2013, e65670 8 J. Mitchell, Streptococcus mitis: walking the line between commensalism and pathogenesis, Mol Oral Microbiol, Vol. 26, 2011, 89-98 9 B.J. Vesper, A. Jawdi, K.W. Altman, G.K. Hai