Osvalda De Giglio1, Christian Napoli1, Grazia Lovero1, Giusy Diella1, Serafina Rutigliano1, Giuseppina Caggiano1, Maria Teresa Montagna2. 1. Department of Biomedical Science and Human Oncology, Hygiene Section, University of Bari "Aldo Moro", Piazza Giulio Cesare 11, 70124 Bari, Italy. 2. Department of Biomedical Science and Human Oncology, Hygiene Section, University of Bari "Aldo Moro", Piazza Giulio Cesare 11, 70124 Bari, Italy. Electronic address: mariateresa.montagna@uniba.it.
Abstract
OBJECTIVES: The purpose of this study was to describe the susceptibility of environmental strains of Legionella spp. to 10 antimicrobials commonly used for legionellosis therapy. A study of environmental strains could be useful to timely predict the onset of antibiotic resistance in the environment before it is evidenced in clinical specimens. METHODS: The minimum inhibitory concentrations (MICs) of 100 environmental Legionella pneumophila (Lpn) strains belonging to serogroups (sgs) 1, 6, 8, and 10 were tested using the E-test methodology on buffered charcoal yeast extract agar supplemented with α-ketoglutarate. The most frequent sgs were selected from those obtained during microbiological surveillance conducted in 2014 in a hospital in Southern Italy. The MICs were read after 2 days of incubation at 35 °C in a humidified atmosphere without CO2. RESULTS: All isolates were inhibited by low concentrations of fluoroquinolones and macrolides. Rifampicin was the most active drug against the isolates in vitro. All Lpn isolates were inhibited by the following drugs (in decreasing order of their MICs): doxycycline>tigecycline>cefotaxime. The MICs of azithromycin, ciprofloxacin, levofloxacin, moxifloxacin, and tigecycline were significantly lower for Lpn non-sg 1 than Lpn sg 1 isolates. CONCLUSIONS: Susceptibility testing of Legionella strains to appropriate antibiotics should be performed often to evaluate the possible emergence of resistance, to improve the outcomes of patients, and to reduce the direct costs associated with hospitalization.
OBJECTIVES: The purpose of this study was to describe the susceptibility of environmental strains of Legionella spp. to 10 antimicrobials commonly used for legionellosis therapy. A study of environmental strains could be useful to timely predict the onset of antibiotic resistance in the environment before it is evidenced in clinical specimens. METHODS: The minimum inhibitory concentrations (MICs) of 100 environmental Legionella pneumophila (Lpn) strains belonging to serogroups (sgs) 1, 6, 8, and 10 were tested using the E-test methodology on buffered charcoal yeast extract agar supplemented with α-ketoglutarate. The most frequent sgs were selected from those obtained during microbiological surveillance conducted in 2014 in a hospital in Southern Italy. The MICs were read after 2 days of incubation at 35 °C in a humidified atmosphere without CO2. RESULTS: All isolates were inhibited by low concentrations of fluoroquinolones and macrolides. Rifampicin was the most active drug against the isolates in vitro. All Lpn isolates were inhibited by the following drugs (in decreasing order of their MICs): doxycycline>tigecycline>cefotaxime. The MICs of azithromycin, ciprofloxacin, levofloxacin, moxifloxacin, and tigecycline were significantly lower for Lpn non-sg 1 than Lpn sg 1 isolates. CONCLUSIONS: Susceptibility testing of Legionella strains to appropriate antibiotics should be performed often to evaluate the possible emergence of resistance, to improve the outcomes of patients, and to reduce the direct costs associated with hospitalization.
Authors: Caitlin Proctor; Emily Garner; Kerry A Hamilton; Nicholas J Ashbolt; Lindsay J Caverly; Joseph O Falkinham; Charles N Haas; Michele Prevost; D Rebecca Prevots; Amy Pruden; Lutgarde Raskin; Janet Stout; Sarah-Jane Haig Journal: Water Res Date: 2021-12-22 Impact factor: 11.236
Authors: Giuseppe Fleres; Natacha Couto; Mariette Lokate; Luc W M van der Sluis; Christophe Ginevra; Sophie Jarraud; Ruud H Deurenberg; John W Rossen; Silvia García-Cobos; Alex W Friedrich Journal: Microorganisms Date: 2018-07-18
Authors: Benedetta Barchielli; Clarissa Cricenti; Francesca Gallè; Elita Anna Sabella; Fabrizio Liguori; Giovanna Da Molin; Giorgio Liguori; Giovanni Battista Orsi; Anna Maria Giannini; Stefano Ferracuti; Christian Napoli Journal: Int J Environ Res Public Health Date: 2022-09-21 Impact factor: 4.614