ABSTRACT
Bacteria use bicarbonate as substrate for crucial metabolic reactions. We report the first case of bacteremia by capnophilic E. coli without the YadF gene (also known as CynT2 or Can2) that needs high concentrations of CO2 to non-enzymatically produce bicarbonate. This lack may also apply to previously reported capnophilic Enterobacteriaceae.
Subject(s)
Bacteremia/microbiology , Bicarbonates/metabolism , Enterobacteriaceae/metabolism , Aged , Carbon Dioxide/metabolism , Carbonic Anhydrases/metabolism , Escherichia coli Proteins/metabolism , Humans , MaleABSTRACT
INTRODUCTION: Neoadjuvant 5-FU-based chemoradiotherapy in resectable rectal cancer (RC) is a standard of treatment. The use of oral fluoropyrimidines and new agents such as oxaliplatin may improve efficacy and tolerance. MATERIAL AND METHODS: Between 1999 and 2009, 126 RC patients with T3-T4 and/or N+ disease were given three successive protocols: UFT (32), UFT-oxaliplatin (75) and capecitabine-oxaliplatin (19), alongside 45 Gy of radiotherapy; with surgery 4-6 weeks after. Adjuvant treatment was given in all patients. The primary objective was pathologic complete response (pCR). RESULTS: Preoperative therapy was well tolerated, with no toxic deaths and a 15% grade 3-4 toxicity rate. Eighty-five percent of patients received the full chemotherapy dose, 56% had an abdominoperineal resection, 6% reinterventions and 57% received the full adjuvant chemotherapy planned. The pCR rate was 13%. The downstaging rate was 80%; 8% had progression of disease. The relapse rate was 20%, with local relapse in 6%. By 5 years of followup, 92% of relapses had occurred. Median follow-up was 73 months, 5- and 10-year disease-free survival rates were 75% and 50%, and 5- and 10-year overall survival rates were 79% and 66% respectively. There was no benefit from the use of oxaliplatin regarding survival or pCR rates. Older patients had worse long-term outcomes. CONCLUSIONS: Neoadjuvant chemoradiotherapy with oral fluoropyrimidines and oxaliplatin is feasible and well tolerated. The risk of early progression is low. However, there was no added benefit with the use of oxaliplatin. There were no relapses in patients with pCR. The role of adjuvant chemotherapy is unclear (AU)