Plasmid-mediated extended spectrum beta-lactamases

Comparative evaluation of the clinical and microbiological efficacy of co-amoxiclav vs cefixime or ciprofloxacin in bacterial exacerbation of chronic bronchitis

In an open randomized study 218 outpatients (159 males and 59 females) ranging between 18 and 85 years of age (mean 61.9) suffering from bacterial exacerbation of chronic bronchitis have been randomly treated: 79 with co-amoxiclav (amoxicillin 875 mg+clavulanic acid 125 mg) twice daily, 69 with cefixime (400 mg) once daily, and 70 with ciprofloxacin (500 mg) twice daily for an average period of 10 days. Before treatment start, 234 bacterial strains (105 Gram-positive and 129 Gram-negative) were isolated as the cause of exacerbation; the leading pathogens were Streptococcus pneumoniae and Haemophilus spp. Eradication rates at the end of treatment were 82.2% for the co-amoxiclav group, 77.6% for the cefixime group, and 81.2% for ciprofloxacin group. Clinical success (cure+improvement) was obtained in 90.8% of the cases treated with co-amoxiclav, in 80.9% for the cefixime group and in 85.7% of patients treated with ciprofloxacin. Seven adverse events (8.9%) of which 4 cases of diarrhea and 3 of itching, were recorded in the co-amoxiclav group. Eleven adverse events (14.7%) were recorded in the cefixime group including gastrointestinal disturbances in 6 patients and mild to moderate increase of liver function in 2. Nine adverse events (12.9%) occurred in the ciprofloxacin group, including insomnia in 3 patients, gastrointestinal disturbances in 2, and serious increase of liver function tests in one patient. It can be concluded that there were no statistically significant differences among the three treatment groups. However, co-amoxiclav demonstrated a higher efficacy rate than cefixime and ciprofloxacin and was better tolerated. Therefore, it can be used as a first-choice drug in the treatment of exacerbation of chronic bronchitis.

Cefotaxime. Unchanged antibacterial activity over years?

During recent years new mechanisms of beta-lactam resistance have developed with the genetic origin on the chromosome or plasmids. Nevertheless, most multicenter studies can demonstrate that cefotaxime has retained its antibacterial activity toward the relevant species. However, it is important to follow the development of resistance closely in hospitals, where epidemic outbreaks of bacterial strains with extended-spectrum beta-lactamases can create difficulties in the treatment of infectious diseases.