Journal of Infection and Chemotherapy

The aim of this study was to evaluate the antimicrobial susceptibilities of probiotic strains that are suggested to be effective for preventing antibiotics-associated diarrhea (AAD). The minimum inhibitory concentrations (MICs) of 17 antibiotics against probiotic strains were tested by the agar plate dilution method or broth microdilution method. In all, eight probiotic strains containing Enterococcus faecalis, Bifidobacterium spp., Clostridium butyricum, and Lactobacillus acidophilus were tested. Although the MIC range was wide, from less than 0.0625 to more than 1,024 μg/ml, the MICs of 11 beta-lactams were high for three of four enterococci, with a range of 32 to more than 1,024 μg/ml. In contrast, fluoroquinolones and vancomycin showed potent activities against all enterococci, of which MICs were 0.25–8 μg/ml. Two Bifidobacterium strains and one Lactobacillus strain showed low MICs against many of the beta-lactams, fluoroquinolones, macrolides, and vancomycin, with MICs of 8 μg/ml or less. Fosfomycin showed generally mild activity against enterococci (MIC, 8–32 μg/ml) and anaerobic strains (MIC, 32 to >1,024 μg/ml), respectively. The probiotics strains with high MIC values may survive in the intestinal tract, even if the patient was concomitantly using the antibiotics in clinical practice. Therefore, our results suggest that adequate combinations of probiotics strains and antibiotics should be important for preventing AAD. Further study is needed to determine the efficacy of probiotics in clinical practice.

This study aimed to develop breakpoints of carbapenems for intraabdominal infections, based on pharmacokinetics (PK) and pharmacodynamics (PD) at the target site. Imipenem, meropenem, and doripenem were each administered to 8–11 patients before abdominal surgery, and venous blood and peritoneal fluid samples were obtained. The drug concentrations in plasma and peritoneal fluid were determined and analyzed using population pharmacokinetic modeling. Using the pharmacokinetic model parameters, a Monte Carlo simulation was performed to estimate the probabilities of attaining the bacteriostatic and bactericidal targets (20% and 40% of the time above the minimum inhibitory concentration [MIC], respectively) in peritoneal fluid. The bacteriostatic and bactericidal breakpoints were defined as the highest MIC values at which the bacteriostatic and bactericidal probabilities in peritoneal fluid were 80% or more. The breakpoints for the minimum and maximum approved dosages of each drug were identical for imipenem, meropenem, and doripenem, and some of these values varied with dosing interval and infusion time. Site-specific PK-PD-based breakpoints are proposed here for the first time, and should help us to select appropriate carbapenem regimens for intraabdominal infections.

We describe a 76-year-old male farmer with no diabetes mellitus and no history of ocular trauma from soil or plants who developed a corneal infection from a plant pathogen. The organism was identified as Corynespora cassiicola based on both the morphological characteristics and the sequence of the internal transcribed spacer region of the ribosomal RNA gene. The patient was treated successfully with a combination of topical and systemic voriconazole. This is the first reported case of keratomycosis caused by C. cassiicola.