[Sensitivity to fosfomycin of multiresistant serotype 012 Pseudomonas aeruginosa. Multicenter study]

In a multicentric study including 214 strains of Pseudomonas aeruginosa, we observed that serotype O12 is more frequently sensitive to fosfomycine than other serotypes strains (72% vs 13.2%, p < 0.000001). Time killing experiments demonstrated that combination of ceftazidime-fosfomycine and amikacine-fosfomycine have usually bactericidal and synergistic activities and could be used for the treatment of multiresistant Pa O12 infections. However, an antagonism between beta-lactams and fosfomycin in disk diffusion needs an adequate concentration of both antibiotics in the site of infection.