Assessing bacterial viability by molecular markers might help accelerate the measurement of antibioticinduced killing. This study investigated whether rRNA could be suitable for this purpose. Cultures of penicillin-susceptible and penicillin-tolerant (Tol1 mutant) Streptococcus gordonii were exposed to mechanistically different penicillin and levofloxacin. Bacterial survival was assessed by viable counts and compared to quantitative real-time PCR amplification of either the 16S rRNA genes or the 16S rRNA, following reverse transcription. Penicillin-susceptible S. gordonii lost >4 log 10 CFU/ml of viability over 48 h of penicillin treatment. In comparison, the Tol1 mutant lost <1 log 10 CFU/ml. Amplification of a 427-bp fragment of 16S rRNA genes yielded amplicons that increased proportionally to viable counts during bacterial growth but did not decrease during drug-induced killing. In contrast, the same 427-bp fragment amplified from 16S rRNA paralleled both bacterial growth and drug-induced killing. It also differentiated between penicillin-induced killing of the parent and the Tol1 mutant (>4 log 10 CFU/ml and <1 log 10 CFU/ml, respectively) and detected killing by mechanistically unrelated levofloxacin. Since large fragments of polynucleotides might be degraded faster than smaller fragments, the experiments were repeated by amplifying a 119-bp region internal to the original 427-bp fragment. The amount of 119-bp amplicons increased proportionally to viability during growth but remained stable during drug treatment. Thus, 16S rRNA was a marker of antibiotic-induced killing, but the size of the amplified fragment was critical for differentiation between live and dead bacteria.

We propose a treatment algorithm based on clinical and radiological criteria. Because of the high failure rate after NOM, PSAE should be the treatment of choice to manage grade I through IV splenic ruptures after colonoscopy in hemodynamically stabilized patients.

Electrical stimulation modulated caecal motility, and provoked localized and propagated colonic contractions.

Background Serum procalcitonin (PCT) is a useful biomarker to tailor the duration of antibiotics in respiratory infections. The objective of this study was to determine whether PCT levels could tailor postoperative antibiotic therapy in patients operated for peritonitis. Method Patients with peritonitis were randomized postoperatively. The control group received antibiotics for a defined duration according to institutional guidelines. In the study group, antibiotics were stopped based on serum PCT levels. Patients were stratified into three categories: (1) gastrointestinal perforation, (2) perforated appendicitis, and (3) postoperative complication. Primary outcome was duration of antibiotics. Results We included 162 patients; 83 and 79 patients in the control group and study group, respectively. In the subgroup of patients with peritonitis due to gastrointestinal perforation, we found 7 days of antibiotics in the PCT group versus 10 days in the control group (p value 0.065). There was no difference in infectious complications, mortality, median length of hospital stay, and necessity to restart antibiotics. Conclusion No significant differences were found in duration of antibiotics when applying PCT guidance. However, in the subgroup of primary perforation of the gastrointestinal tract, there was a difference in duration of antibiotics in favor of the PCT group without obtaining significance, as the study was not powered for subgroup analysis. Further studies including only this subgroup should be performed.