In vitro activity of thiamphenicol, erythromycin and fluoroquinolones against Legionella pneumophila

Antibiotic Resistance of Legionella pneumophila in Clinical and Water Isolates-A Systematic Review

The current systematic review investigates the antibiotic susceptibility pattern of Legionella pneumophila isolates from the 1980s to the present day, deriving data from clinical and/or water samples from studies carried out all over the world. Eighty-nine papers meeting the inclusion criteria, i.e., “Legionella pneumophila” and “resistance to antibiotics”, were evaluated according to pre-defined validity criteria. Sixty articles referred to clinical isolates, and 18 articles reported water-related L. pneumophila isolates, while 11 articles included both clinical and water isolates. Several methods have been proposed as suitable for the determination of MICs, such as the E-test, broth and agar dilution, and disk diffusion methods, in vivo and in vitro, using various media. The E-test method proposed by the European Society of Clinical Microbiology and Infectious Diseases (EUCAST) seems to be the second most frequently used method overall, but it is the preferred method in the most recent publications (2000–2019) for the interpretation criteria. Erythromycin has been proved to be the preference for resistance testing over the years. However, in the last 19 years, the antibiotics ciprofloxacin (CIP), erythromycin (ERM), levofloxacin (LEV) and azithromycin (AZM) were the ones that saw an increase in their use. A decrease in the sensitivity to antibiotics was identified in approximately half of the reviewed articles.

A Therapeutic Approach in the Treatment of Infections of the Upper Airways: Thiamphenicol Glycinate Acetylcysteinate in Sequential Treatment (Systemic-Inhalatory Route)

Eight hundred and seventeen patients with upper respiratory tract infections were treated with thiamphenicol glycinate acetylcisteinate (TGA) or other standard antibiotics for 6–10 days in a randomised trial. In 419 out of 817 patients, the symptomatology was severe and they were treated with TGA in sequential therapy (TGA 500 mg- as thiamphenicol- b.i.d. intramuscularly on the first day and TGA 500 mg b.i.d by aerosol during the following days) (n=151), or with antibiotics of comparison (n=268) given intramuscularly. In this group the disappearance of the symptomatology with TGA ranged from 90% of the patients with otitis media to 94% in pharyngotonsillitis and rhinosinusitis; in this latter group TGA was significantly better than cefazolin. In 398 patients with mild symptomatology TGA (250 mg - as thiamphenicol- b.i.d.) was given by aerosol (n=149) and the antibiotics of comparison by oral route (n=249). In TGA patients, the disappearance of symptoms was achieved in 87% of those with rhinosinusitis, in 88% of those with pharyngotonsillitis and in 91% of those with otitis media. S. pyogenes, S. pneumoniae and H. influenzae were the most frequently isolated pathogens, and none of the isolated bacteria proved to be resistant to TGA. Microbiological eradication was obtained in TGA groups in a percentage of patients ranging from 90.2 to 96.0% in those with severe forms, and from 86.2 to 91.6% in those with a mild clinical picture. Investigators rated the TGA efficacy as “excellent” in 96–100% of the patients with severe forms and in 85.5%–100% of the patients with mild forms, whereas in the group of patients with rhinosinusitis the comparison of TGA versus other treatment was significantly in favour of TGA. The Investigator rating of treatment tolerability significantly favoured TGA in sequential treatments in comparison to the other antibiotics. No patient dropped out from the trial because of adverse events.