G Taccetti1, M Denton2, K Hayes3, P Drevinek4, I Sermet-Gaudelus5. 1. Cystic Fibrosis Centre, Anna Meyer Children's University Hospital, Viale Pieraccini 24, Firenze 50139, Italy. Electronic address: g.taccetti@meyer.it. 2. Leeds Teaching Hospitals NHS Trust, Department of Microbiology, Old Medical School, Leeds General Infirmary, Leeds LS1 3EX, UK. Electronic address: milesdenton@nhs.net. 3. Centre for Experimental Medicine, The Queen's University of Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK. Electronic address: k.hayes@qub.ac.uk. 4. Department of Medical Microbiology, Motol University Hospital and 2nd Faculty of Medicine, Charles University, V Uvalu 84, Prague, CZ 150 06, Czech Republic. Electronic address: Pavel.drevinek@lfmotol.cuni.cz. 5. Isabelle Sermet-Gaudelus, Service de Pneumologie et Allergologie Pédiatriques, Centre de Ressources et de Compétence de la Mucoviscidose, Hôpital Necker Enfants Malades 149 rue de Sévres, INSERM U1151, Institut Necker Enfants Malades, Université Paris Sorbonne, Paris 75743, France. Electronic address: isabelle.sermet@aphp.fr.
Abstract
BACKGROUND: Definition of Pseudomonas aeruginosa (Pa) microbiological status is essential for patients' inclusion in clinical trials. The aim of this study was to agree on the definitions of Pa infection status for initial infection, eradication and chronic infection to be used in clinical trials and to propose additional future study areas. METHODS: An exhaustive literature search was performed. The clinimetric properties of different definitions of Pa microbiological status were evaluated. RESULTS: Historical studies have mostly used culture-based definitions, although some have also involved complementary anti-Pa antibodies. Clinimetric analysis showed great variability in the definitions used, leading to differences in reliability, validity, responsiveness to treatment and correlation with outcome measures. Use of serology for initial Pa infection and successful Pa eradication introduced a greater level of complexity as antibody tests are not standardised. Moreover, the chronology of the immune response to Pa antigenic determinants was not completely clear. Chronic Pa infection was characterized by high levels of antibodies and good concordance between culture results and serology. CONCLUSIONS: Microbiological monitoring, regular sampling from the airways and standardization of culture methods remain essential requisites for microbiological definitions. Despite limitations, serology should be incorporated in the definitions of initial infection and eradication used in clinical trials to better classify patients at enrolment, mainly in non-expectorating children. This requires standardization of serological testing.
BACKGROUND: Definition of Pseudomonas aeruginosa (Pa) microbiological status is essential for patients' inclusion in clinical trials. The aim of this study was to agree on the definitions of Pa infection status for initial infection, eradication and chronic infection to be used in clinical trials and to propose additional future study areas. METHODS: An exhaustive literature search was performed. The clinimetric properties of different definitions of Pa microbiological status were evaluated. RESULTS: Historical studies have mostly used culture-based definitions, although some have also involved complementary anti-Pa antibodies. Clinimetric analysis showed great variability in the definitions used, leading to differences in reliability, validity, responsiveness to treatment and correlation with outcome measures. Use of serology for initial Pa infection and successful Pa eradication introduced a greater level of complexity as antibody tests are not standardised. Moreover, the chronology of the immune response to Pa antigenic determinants was not completely clear. Chronic Pa infection was characterized by high levels of antibodies and good concordance between culture results and serology. CONCLUSIONS: Microbiological monitoring, regular sampling from the airways and standardization of culture methods remain essential requisites for microbiological definitions. Despite limitations, serology should be incorporated in the definitions of initial infection and eradication used in clinical trials to better classify patients at enrolment, mainly in non-expectorating children. This requires standardization of serological testing.
Authors: Paul Briaud; Sylvère Bastien; Laura Camus; Marie Boyadjian; Philippe Reix; Catherine Mainguy; François Vandenesch; Anne Doléans-Jordheim; Karen Moreau Journal: Front Cell Infect Microbiol Date: 2020-06-03 Impact factor: 5.293