Effectiveness of antibiotics for acute sinusitis in real-life medical practice.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Determining bacterial aetiology of acute sinusitis is difficult without employing invasive procedures. Most episodes of acute sinusitis resolve spontaneously. Antibiotics have demonstrated efficacy for the treatment of acute bacterial sinusitis in clinical trials yet little is known of their effectiveness in real-life treatment settings. WHAT THIS STUDY ADDS: Most cases of untreated acute sinusitis resolved spontaneously. Antibiotics were more effective when given within the first 10 days of treatment. This had no effect on later recurrence. Patients with poor oro-dental condition or recent antibiotic use may derive the most benefit from an antibiotic prescription and this should be considered by prescribers. The antibiotics used were found to be equally effective. Existing recommendations to identify acute sinusitis with high probability of bacterial origin, such as the French recommendations, fever or duration of symptoms fail to identify patients in whom antibiotics are more effective. AIMS: To assess the effectiveness of antibiotics in acute bacterial sinusitis. METHODS: This was a prospective cohort study with 2 months follow-up of 5640 patients with acute sinusitis included by a random sample from 1174 GPs and 120 ENT specialists. Main outcomes were short-term initial success, defined as the absence of prescription of (another) antibiotic or sinus lavage within 10 days, and lack of recurrence between the 11th and 60th day, after initial success. RESULTS: Initial success was found in 88.7% (95% CI 85.1, 91.4%) of patients without antibiotic prescription at inclusion and 96.2% (95% CI 95.7, 96.7%) of patients prescribed antibiotics. The 10 day adjusted hazard ratio (HR) for treatment failure (new antibiotic prescription or sinus drainage) with initial antibiotics compared with no antibiotics was 0.30 (95% CI 0.21, 0.42) with no difference between antibiotics. Antibiotics were more effective in patients with poor oro-dental condition (HR 0.04, 95% CI 0.01, 0.20) and in patients who had already used antibiotics during the previous 2 months (HR 0.09, 95% CI 0.03, 0.28). For patients without failure at 10 days, recurrence between the 11th and 60th day was similar whether or not they had initially been prescribed an antibiotic, 94.1% (95% CI 93.4, 94.7%) and 93.4% (95%CI 90.3, 95.5%), respectively. CONCLUSION: Most acute sinusitis cases not prescribed antibiotics resolve spontaneously. Antibiotics reduced by 3.3-fold the risk of failure within 10 days, without impact on later recurrence. The greatest benefit of antibiotics was found for patients with poor oro-dental condition or with antibiotic use within the previous 2 months.

Carriage of CTX-M-15-producing Escherichia coli isolates among children living in a remote village in Senegal.

Two out of 20 children with no known antibiotic exposure, living in a very remote Senegalese village, were found to be fecal carriers of a multiresistant Escherichia coli clone that produced CTX-M-15. This highlights the current massive spread of extended-spectrum beta-lactamases, even in isolated communities.

Randomized comparison of serum teicoplanin concentrations following daily or alternate daily dosing in healthy adults.

Trough serum teicoplanin concentrations were compared in healthy adults following intravenous administration of one of two regimens: (i) 12 mg/kg of body weight every 12 h for 3 doses and then 15 mg/kg every 48 h for 4 doses (n = 16 subjects) or (ii) 6 mg/kg every 12 h for 2 doses and then 6 mg/kg every 24 h for 9 doses (n = 8 subjects). The mean +/- standard deviation trough concentrations in serum on day 11 (24 and 48 h after administration of the last dose for the daily and alternate-day dosing schedules, respectively) were 16.0 +/- 2.1 and 17.9 +/- 3.5 mg/liter for subjects receiving the two regimens, respectively, by a fluorescence polarization immunoassay. The limits of the 95% confidence interval of the difference (-0.2, 3.6 mg/liter) determined by a nonparametric test were situated above the -1.3-mg/liter maximum set difference and indicated a noninferiority of the alternate-day dosing to the daily dosing. Throughout the study the individual trough concentrations in serum in the alternate-day dosing group constantly exceeded 10 mg/liter, the presently recommended target concentration for the treatment of severe infections. The trough concentrations in the sera of all subjects were bactericidal for six Staphylococcus aureus strains for which teicoplanin MICs are between 0.5 and 4 mg/liter. The bactericidal activity of serum was related to total teicoplanin (protein bound and unbound). In conclusion, an alternate-day dosing schedule (15 mg/kg on alternate days following administration of a 12-mg/kg loading dose three times every 12 h) could be considered for further efficacy and safety studies.

Antibiotic safety assessment.

Antibiotics usually have positive risk-benefit ratios, their adverse effects being generally mild and reversible on treatment cessation. However, severe adverse drug reactions (ADR), associated with significant mortality and morbidity have resulted in the withdrawal of several active antibiotics, including new fluoroquinolones. Adverse reactions to antibiotics are often poorly documented. The purpose of this article is to examine current tools for investigating and preventing antibiotic toxicity and to suggest future lines of investigation. Structure/ADR relationships have been investigated with various antibiotics (beta-lactams, macrolides, quinolones, etc.) in an attempt to reduce the risk of adverse reactions. Some reactions can be linked to the drug's stereochemical composition. In the case of quinolones for instance, particularly ofloxacin and its derivatives, experimental data show that individual enantiomers have different toxicities. Another major factor that influences the risk of ADRs in a given population is metabolic variability, due to genetic differences in the relevant drug-metabolizing enzymes. Idiosyncratic antibiotic toxicity can be caused by a chemically reactive metabolite. Recent advances in molecular biology, and especially in individual genomic characterization (DNA chip technology, etc.), could in future be useful for identifying patients who are at a special risk of ADR. Finally, certain pharmacokinetic parameters (AUC, Cmax, etc.) can be used to predict adverse effects.