Faecal microbiota transplantation plus selected use of vancomycin for severe-complicated Clostridium difficile infection: description of a protocol with high success rate.

BACKGROUND: Severe and severe/complicated Clostridium difficile infection (CDI) can result in ICU admission, sepsis, toxic megacolon and death. In this setting, colectomy is the standard of care but it is associated with a 50% mortality. AIM: To evaluate safety and efficacy of a sequential faecal microbiota transplantation (FMT) and antibiotic protocol in severe and severe/complicated CDI patients who are at high risk for colectomy. METHODS: All patients with severe and severe/complicated CDI refractory to oral vancomycin ± rectal vancomycin and intravenous metronidazole therapy were offered FMT. Treatment consisted of sequential FMTs via colonoscopy with the need for repeat FMT and continued vancomycin guided by clinical response and pseudomembranes at colonoscopy. RESULTS: A total of 29 patients underwent FMT between July 2013 and August 2014. The overall treatment response of endoscopic sequential FMT was 93% (27/29), with 100% (10/10) for severe CDI and 89% (17/19) for severe/complicated CDI. A single FMT was performed in 62%, two FMTs were performed in 31% and three FMTs in 7% of patients. The use of non-CDI antibiotics predicted repeat FMT (odds ratio = 17.5). The 30-day all-cause mortality after FMT was 7%, and the cumulative 3-month survival was 76%. Of the two patients who died within 30 days, one underwent colectomy and succumbed to sepsis; the other died from septic shock related to CDI. CONCLUSION: The success of a treatment protocol for severe and severe/complicated involving faecal microbiota transplantation and continued vancomycin in selected patients was high, and it warrants further evaluation.

3-Quaternary ammonium 1-carba-1-dethiacephems.

A series of structurally unique 1-carba-1-dethiacephems is described. The structural stability of the 1-carba-1-dethiacephem nucleus was essential for the preparation of this series of 3-quaternary ammonium carbacephems. The known p-nitrobenzyl 7 beta-(phenoxyacetamido)- 3-[(trifluoromethyl)sulfonyl]oxy]-1-carba-1-dethia-3-cephem- 4-carboxylate served as both a quaternization substrate as well as a precursor to derivatives such as allyl 7 beta-[[2-[allyloxy)carbonyl]amino-4- thiazoly] (methoxyimino)acetyl]amino]-3-[(trifluoromethyl) sulfonyl] oxy]-1-carba-1-dethia-3-cephem-4-carboxylate. Quaternization of these enol triflates was accomplished either by dissolution in acetonitrile containing the base or by dissolution in the base, with or without warning to 50 degrees C. Bases nucleophilic enough to displace the triflate include a variety of substituted pyridines and N-methylimidazole. Deprotection then produced a very active series of 1-[7 beta-[(2-amino- 4-thiazolyl)(methoxyimino)acetyl]amino]-2-carboxy-8-oxo- 1-azabicyclo[4.2.0]oct-2-en-3-yl] quaternary ammonium hydroxide inner salts. These compounds were extremely potent antibacterials against a broad range of Gram-positive and -negative bacteria including constitutive cephalosporinase producers, such as Enterobacter cloacae. The compounds exhibit similar hydrolysis kinetics and pharmacokinetics to the analogous cephalosporin-3'-quaternary ammonium salts.

Comparative reactivity of 1-carba-1-dethiacephalosporins with cephalosporins.

Nine matched pairs of cephalosporins and their 1-carba-1-dethiacephalosporin analogues have been compared with regard to microbiological activity, beta-lactam carbonyl infrared absorption, and aqueous stability. In general the microbiological activity of the pairs of compounds were very similar across a broad range of bacteria. The infrared absorption bands for the beta-lactam carbonyls of the pairs indicated a general trend for the 1-carba-1-dethiacephalosporins to absorb at lower frequencies than the corresponding cephalosporins. All of the 1-carba-1-dethiacephalosporins did however present a striking stability enhancement over their cephalosporin counterparts at pH = 10 or 11 in water. This marked contrast of MIC similarity with the observed differences in chemical reactivity clearly demonstrates hydroxide ion catalyzed hydrolysis is not a good model for transpeptidase activity unless the compounds comprise a limited domain of structural type.

3-trifluoromethylcarbacephems: synthesis of broad spectrum antibacterial compounds.

The enhanced stability of the carbacephem nucleus over the corresponding cephalosporin nucleus has allowed the synthesis of 7-arylglycyl-3-trifluoromethyl-carbacephems. These unique carbacephems possess broad spectrum activity and high stability to both plasmid and chromosomally mediated beta-lactamases.