In Vitro Antibacterial Activity of Pazufloxacin (PZFX) against Clinical Isolates from Infectious Enteritis

Abstract

Antibacterial activity of pazufloxacin (PZFX) against 65 strains of Shigella spp., 13 strains of Salmonella spp., 7 strains of Escherichia coli, 4 strains of Vibrio parahaemolyticus, 4 strains of V. cholerae 01, 2 strains of Aeromonas spp., 4 strains of Plesionomas shigelloides and 3 strains of V. cholerae non-01 isolated from patients of infectious enteritis and carriers was compared with that of ofloxacin (OFLX), ciprofloxacin (CPFX), tosufloxacin (TFLX) and nalidixic acid (NA). The MIC₉₀ of PZFX against Shigella spp., Salmonella spp. and E. coli were 0.025, 0.025 and 0.025μ g/ml, respectively. The MIC₉₀ of PZFX against Shigella spp. was comparable to that of CPFX, 2-fold higher than that of TFLX and 4-fold lower than that of OFLX. Against Salmonella spp., MIC₉₀ of PZFX was comparable to TFLX and 2-to 8-fold lower than those of CPFX and OFLX. PZFX showed the highest antibacterial activity between the drugs tested. Against other species, the MIC90 values of PZFX were ≤-0.006-0.1 μg/ml. No NA-resistant isolates were observed.
The antibacterial activity of PZFX against stocked strains (clinical isolates from Aug 1989 to Feb 1991), containing 51 strains of Shigella spp., 50 strains of Salmonella spp., 19 strains of E. coli, 12 strains of V. cholerae 01 and 13 strains of V. parahaemolyticus, was also investigated. The MIC₉₀ of PZFX of each strains were 0.05μg/ml for Shigella spp., 0.05μg/ml for Salmonella spp., 0.1μg/ml for E. coli, 0.0125 μg/ml for V. cholerae 01, 0.2 μg/ml for V. parahaemolyticus, respectively.
As shown above, PZFX has strong antibacterial activity against isolates from infectious enteritis and this suggests the usefulness of PZFX for the treatment of these patients and carriers.