Heterogeneous penetration of cefpirome and moxifloxacin into abscesses after simultaneous administration in humans

Results At incision performed 158 ± 112 min after administration, cefpirome concentrations in abscess ranged from below the limit of quantification to 47 mg/L (8.4 ± 14.1 mg/L), and moxifloxacin concentrations ranged from below the limit of quantification to 9.2 mg/L (1.9 ± 3.4 mg/L). Relative to plasma, abscess concentrations of moxifloxacin were significantly higher than of cefpirome (p = 0.037). Inhibitory concentrations of both antibiotics reported for abscess-relevant bacterial species were reached in several, but not in all abscess observations. Antibiotic abscess penetration could not be adequately explained considering covariates such as pH of abscess fluid, or the ratio of surface area to volume of abscesses, linked to plasma pharmacokinetics.