Cephamycin A

Cephamycin C (CepC) is a β-lactam antibiotic that belongs to the cephalosporin class of drugs. This compound stands out from other cephalosporins for its greater resistance to β-lactamases, which are enzymes produced by pathogenic microorganisms that present a major mechanism of bacterial resistance to β-lactam antibiotics. Cephamycin C is produced by the bacterium Streptomyces clavuligerus. Knowledge about the stability of the compound under different values of pH is important for the development of the process of production, extraction, and purification aimed at obtaining higher yields. Therefore, the stability of cephamycin C under different pH levels (2.2, 6.0, 7.0, 7.6, and 8.7) at 20 °C was evaluated in this study. Ultrafiltered broth from batch fermentations of S. clavuligerus was used in the trials. The results indicated that cephamycin C is a more stable compound than other β-lactam compounds such as penicillin and clavulanic acid. A higher degradation rate was observed at very acidic or basic pH levels, while this rate was lower at quasi-neutral pH levels. After 100 h of trial, the initial CepC showed 46 % degradation at pH 2.2, 71 % degradation at pH 8.7, and varied from 15 to 20 % at quasi-neutral pH levels.

Objectives: To investigate the correlation between cephamycin consumption and the prevalence of antimicrobial resistance in Acinetobacter baumannii. Methods: Cephamycins consumption was expressed as defined daily dose (DDD) per 1,000 patient days by World Health Organization (WHO) Anatomical Therapeutic Chemical (ATC) classification index from 2001 to 2009. The incidences of antimicrobial resistance in A. baumannii were calculated using WHONET 5.4 software in the Microbiology Department. Correlation coefficient was used for statistical analysis. Results: The results showed that cefmetazole and total cephamycin consumption (i.e., cefmetazole, cefoxitin, cefminox) both positively correlated with the percentages of A. baumannii resistance to piperacillin/tazobactam, ceftazidime, cefepime, imipenem/cilastatin, amikacin, levofloxacin, meropenem, respectively, these antimicrobial agents involved beta-lactams, carbapenems, aminoglycosides and fluroquinolones. In addition, the A. baumannii resistance rates of piperacillin/tazobactam, ceftazidime, cefepime, imipenem/cilastatin, meropenem, amikacin, levofloxacin were associated with the A. baumannii resistance rates of a number of antimicrobial drugs. This finding indicated the possible cross-resistances in four different classes of antimicrobial drugs. It could be due to multidrug resistance in A. baumannii. Conclusions: The cephamycin consumption was significantly related to the prevalence of the antimicrobial drug resistance and might be correlated with multidrug resistance in A. baumannii. Hence, the prescription of cephamycin should be reduced and optimized in order to avoid the rapid increase of antimicrobial resistance in A. baumannii.

Cephamycin-associated hemorrhages have been reported since their launch. This research aimed to determine risk factors for cephamycin-associated hemorrhagic events and produce a risk scoring system using National Taiwan University Hospital (NTUH) database. Patients who were older than 20 years old and consecutively used study antibiotics for more than 48 hours (epidode) at NTUH between January 1st, 2009 and December 31st, 2015 were included. The population was divided into two cohorts for evaluation of risk factors and validation of the scoring system. Multivariate logistic regression was used for the assessment of the adjusted association between factors and the outcome of interest. Results of the multivariate logistic regression were treated as the foundation to develop the risk scoring system. There were 46402 and 22681 episodes identified in 2009-2013 and 2014-2015 cohorts with 356 and 204 hemorrhagic events among respective cohorts. Use of cephamycins was associated with a higher risk for hemorrhagic outcomes (aOR 2.03, 95% CI 1.60-2.58). Other risk factors included chronic hepatic disease, at least 65 years old, prominent bleeding tendency, and bleeding history. A nine-score risk scoring system (AUROC = 0.8035, 95% CI 0.7794-0.8275; Hosmer-Lemeshow goodness-of-fit test p = 0.1044) was developed based on the identified risk factors, with higher scores indicating higher risk for bleeding. Use of cephamycins was associated with more hemorrhagic events compared with commonly used penicillins and cephalosporins. The established scoring system, CHABB, may help pharmacists identify high-risk patients and provide recommendations according to the predictive risk, and eventually enhance the overall quality of care.