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CASE PRESENTATION: We report a rare case of Moraxella bovis bacteremia and polyarticular septic arthritis in a 37-year-old pregnant woman with HIV who injects drugs. Two sets of blood cultures obtained 5 hours apart were positive for gram-negative bacilli, and purulent fluid was present intra-operatively from both her left knee and her right third MCP joints. DIAGNOSIS: Organism identification using ligation sequencing confirmed both her blood culture and synovial tissue isolates as M. bovis. Her infection was initially treated with third-generation cephalosporins and later changed to moxifloxacin because of a drug reaction; although she defervesced clinically with improvement in her C-reactive protein levels, she died most likely as a result of a non-traumatic fat embolism after an elective cesarean delivery. DISCUSSION: In contrast to Moraxella catarrhalis, other Moraxella species are rarely associated with disease in human hosts. M. bovis is classically associated with infectious bovine keratoconjunctivitis in cattle; interestingly, our patient denied significant animal exposure. To the authors’ knowledge, this is the first case describing infection secondary to M. bovis in an adult host.

SUMMARY Infections remain a major cause of death worldwide and antimicrobial resistance is increasing. With fewer new antimicrobial agents in development it is imperative for available antibiotics to last by observing key points: judicious use, appropriate doses and optimizing regimen compliance in order to reduce the risk of increasing resistance. This review discusses these issues, using treatment of the respiratory tract pathogen Streptococcus pneumoniae with the macrolide clarithromycin as a case study. Clarithromycin is active against common respiratory pathogens achieving high tissue, fluid and serum levels, and has a relatively short half-life. These characteristics influence the risk of developing resistance when compared with erythromycin or azithromycin. High local drug concentrations further reduce the risk of therapeutic failure. Long half-lives associated with a long tail in the curve of minimum inhibitory concentration (MIC) over time may increase the risk of emerging resistant strains. Azit...

The CANWARD study (Canadian Ward Surveillance Study) assessed the antimicrobial susceptibility of a variety of available agents against 15 644 pathogens isolated from patients in Canadian hospitals between 2007 and 2009. The most active (based on MIC data) agents against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci were daptomycin, linezolid, tigecycline, and vancomycin (MRSA only) with MIC(90)'s (μg/mL) of 0.25 and 2, 2 and 2, 0.5 and 0.12, and 1, respectively. The most active agents against extended-spectrum β-lactamase-producing Escherichia coli were colistin (polymyxin E), doripenem, ertapenem, meropenem, and tigecycline with MIC(90)'s (μg/mL) of 1, ≤ 0.12, 0.25, ≤ 0.12, and 1, respectively. The most active agents against Pseudomonas aeruginosa were amikacin, cefepime, ceftazidime, colistin, doripenem, meropenem, and piperacillin-tazobactam with MIC(90)'s (μg/mL) of 32, 16, 32, 2, 4, 8, and 64, respectively. Overall, the most active agents versus Gram-positive cocci from Canadian hospitals were vancomycin, linezolid, daptomycin, and tigecycline and versus Gram-negative bacilli were amikacin, cefepime, doripenem, ertapenem (excluding Pseudomonas aeruginosa), meropenem, piperacillin-tazobactam, and tigecycline (excluding Pseudomonas aeruginosa).

The purpose of this study was to assess the adequacy of our institution's ultrasound probe-disinfecting protocols, determine compliance with the guidelines, and then implement changes if needed.We first assessed the prevalence of bacterial contamination (and thus the potential for bacterial transmission) by swabbing all ultrasound probes (n = 31) in the radiology department and culturing the samples. Next, in conditions simulating the typical work environment, we determined the efficacy of our probe-disinfecting protocols by seeding probes with 10(4)-10(9) CFU/mL of methicillin-resistant Staphylococcus aureus (MRSA), disinfecting the seeded probes with 0.5% accelerated hydrogen peroxide, and then swabbing the disinfected probes to assess for bacterial growth.Seven of 31 (22.6%) probes were positive for bacterial growth--none of which were endocavity probes (0/4). Four of 14 visibly soiled probes (28.6%) showed bacterial growth, and four of seven probes positive for bacteria (57.1%) were visibly soiled. No MRSA grew after seeding probes with MRSA and then disinfecting with 0.5% accelerated hydrogen peroxide. Sonography guidelines and general disinfecting guidelines were reviewed.Our protocols for disinfecting nonendocavity and endocavity probes are compliant with sonography guidelines and general disinfecting guidelines. Although limited by a small sample size, our study showed that our protocol for disinfecting endocavity probes seems adequate. With a 25.9% bacterial contamination rate for nonendocavity probes, the adequacy of our protocol for disinfecting nonendocavity probes is more debatable; however, this bacterial contamination rate is at the lower end of the values reported in the literature. With the use of an effective disinfectant, education of sonographers, and implemented changes, we hope to decrease bacterial contamination rates and thus decrease the potential for bacterial transmission.