In vitro synergistic/additive activity of levofloxacin with meropenem against Stenotrophomonas maltophilia

Synergy testing of levofloxacin and meropenem by Etest and time–kill assay (TKA) was performed against 30 genetically unique clinical Stenotrophomonas maltophilia isolates. Synergy was demonstrated in 18/30 (60%) isolates by Etest and in 13/30 (43%) by TKA; the remaining isolates were indifferent. Methods showed agreement for 25/30 (83%) of isolates.