Disclosed are methods for treating various bacterial infections with (2R,4S,4aS)-11-fluoro-2,4-dimethyl-8-[(4S) -4-methyl-2-oxo-1,3-oxazolidin-3-yl]-1,2,4,4a-tetrahydro-2'H<; /i>;,6H-spiro[1,4-oxazino[4,3-a][1,2]oxazolo[4,5-g] quinoline-5,5'-pyrimidine]-2',4',6' (1'H,3'H)-trione, or a pharmaceutically acceptable salt thereof.Se divulgan métodos para tratar diversas infecciones bacterianas con (2R,4S,4aS)-11-fluoro-2,4-dimetil-8-[(4S)-4-metil-2-oxo-1,3-ox azolidin-3-il]-1,2,4,4a-tetrahidro-2´H,6H-espiro[1,4-oxazino[4,3- a][1,2]oxazolo[4,5-g]quinolin-5,5'-pirimidin]-2',4´,6´(1´H,3´H)-t riona, o una de sus sales farmacéuticamente aceptables.