The role of telavancin in the treatment of MRSA infections in hospital

Background: Serious infections caused by Gram-positive bacteria, particularly multi-drug resistant, are an important cause of morbidity and mortality in patients admitted to intensive care units. Thus, new antibiotics covering these pathogens are urgently needed. Objective: To review characteristics of telavancin, a novel antibiotic intended to use for treating infections caused by difficult Gram-positive bacteria, such as Staphylococcus aureus, resistant to meticillin or vancomycin, multi-drug-resistant Streptococcus pneumoniae or glycopeptide-resistant enterococci. Methods: The studies on microbiological activity, clinical efficacy and safety of telavancin were reviewed. Results/conclusion: Telavancin is a lipoglycopeptide administered intravenously once-daily and excreted with urine. It proved to be microbiologically active against numerous Gram-positive pathogens including drug-resistant staphylococci, enterococci and pneumococci. Large randomized Phase II and III clinical trials on efficacy and safety of telavancin in treating complicated skin and skin structure infections reported telavancin to be non-inferior to standard treatment (mostly vancomycin). Preliminary data on telavancin in hospital-acquired pneumonia, including ventilator-associated pneumonia, documented that telavancin was efficacious for this indication. Overall incidence of adverse events was similar for telavancin and the comparator arms. Mild and transient disgeusia, nausea and vomiting resulted to be more frequent in telavancin group. Increase in creatinine values was also observed in telavancin arm.     

Seasonality of staphylococcal infections

Characterization of seasonal variation of Staphylococcus aureus is important in understanding the epidemiology of, and designing preventive strategies against this highly virulent and ever-evolving pathogen. In this review, we summarize the findings of epidemiological studies that have evaluated seasonality in S. aureus colonization and infection. Although most studies published to date are methodologically weak, some seasonal variation in the occurrence of S. aureus infection appears to exist, particularly an association of warm-weather months with S. aureus skin and soft-tissue infections. We highlight the limitations of the published literature, and provide suggestions for future studies on this topic.     

Identification of a methicillin-resistant Staphylococcus aureus inhibitory compound isolated from Serratia marcescens

In this study, we identified an antimicrobial compound produced by the Gram-negative bacterium Serratia marcescens. Colonies of S. marcescens inhibited the growth of nine different methicillin-resistant Staphylococcus aureus (MRSA) isolates and several other tested Gram-positive bacterial species, but not Gram-negative bacteria. Genetic analysis revealed the requirement for the swrW gene which codes for a non-ribosomal peptide synthetase that generates the cyclodepsipeptide antibiotic serratamolide, also known as serrawettin W1. This is the first report describing the anti-MRSA properties of serratamolide.     

Comparing a single-day swabbing regimen with an established 3-day protocol for MRSA decolonization control

ObjectivesSuccess of methicillin-resistant Staphylococcus aureus (MRSA) decolonization procedures is usually verified by control swabs of the colonized body region. This prospective controlled study compared a single-day regimen with a well-established 3-day scheme for noninferiority and adherence to the testing scheme.MethodsTwo sampling schemes for screening MRSA patients of a single study cohort at a German tertiary-care hospital 2 days after decolonization were compared regarding their ability to identify MRSA colonization in throat or nose. In each patient, three nose and three throat swabs were taken at 3- to 4-hour intervals during screening day 1, and in the same patients once daily on days 1, 2 and 3. Swabs were analysed using chromogenic agar and broth enrichment. The study aimed to investigate whether the single-day swabbing scheme is not inferior to the 3-day scheme with a 15% noninferiority margin.ResultsOne hundred sixty patients were included, comprising 105 and 101 patients with results on all three swabs for decolonization screening of the nose and throat, respectively. Noninferiority of the single-day swabbing scheme was confirmed for both pharyngeal and nasal swabs, with 91.8% and 89% agreement, respectively. The absolute difference of positivity rates between the swabbing regimens was 0.025 (−0.082, 0.131) for the nose and 0.006 (−0.102, 0.114) (95% confidence interval) for the pharynx as calculated with McNemar's test for matched or paired data. Compliance with the single-day scheme was better, with 12% lacking second-day swabs and 27% lacking third-day swabs from the nostrils.ConclusionsThe better adherence to the single-day screening scheme with noninferiority suggests its implementation as the new gold standard.     

Ceftaroline fosamil as first-line versus second-line treatment for acute bacterial skin and skin structure infections (ABSSSI) or community-acquired bacterial pneumonia (CABP)

The Clinical Assessment Program and Teflaro^® Utilization Registry (CAPTURE) is a multicenter registry study of acute bacterial skin and skin structure infection (ABSSSI) and community-acquired bacterial pneumonia (CABP) patients treated with ceftaroline fosamil in the US. Data for this analysis were collected between August 2011 and February 2013 at US study centres by randomly ordered chart review. Clinical success rates among ABSSSI patients were >81% when ceftaroline fosamil was used as first- or second-line therapy, including monotherapy and concurrent therapy. Among CABP patients, clinical success rates were >77% among first-line and second-line patients and patients who received first-line concurrent therapy or second line monotherapy or concurrent therapy. For CABP patients treated with ceftaroline fosamil as first-line monotherapy, the clinical success rate was 70%. Ceftaroline fosamil is an effective treatment option for patients with ABSSSI or CABP with similar clinical success rates when used as first-line or second-line treatment.     

Genetic diversity and antimicrobial resistance of Staphylococcus aureus from recurrent tonsillitis in children

The aim of this study was to analyze the prevalence of Staphylococcus aureus in the tonsils of children subjected tonsillectomy due to recurrent tonsilitis and to determine the spa types of the pathogens, carriage of virulence genes and antimicrobial resistance profiles. The study included 73 tonsillectomized children. Bacteria, including S. aureus were isolated from tonsillar surface prior to tonsillectomy, recovered from tonsillar core at the time of the surgery, and from posterior pharynx 2–4 weeks after the procedure. Staphylococcus aureus isolates were compared by spa typing, tested for antimicrobial susceptibility and for the presence of superantigenic toxin genes (sea-seu, eta, etb, tst, lukS/lukF-PV) by multiplex polymerase chain reaction. Seventy-three patients (mean 7.1 ± 4.1 years, 61.6% male) were assessed. The most commonly isolated bacteria were S. aureus. The largest proportion of staphylococcal isolates originated from tonsillar core (63%), followed by tonsillar surface (45.1%) and posterior pharynx in tonsillectomized children (18.2%, p = 0.007). Five (6.3%) isolates were identified as MRSA (mecA-positive). Up to 67.5% of the isolates synthesized penicillinases (blaZ-positive isolates), and 8.8% displayed MLS_B resistance. The superantigenic toxin genes were detected in more than half of examined isolates (56.3%). spa types t091, t084, and t002, and clonal complexes (CCs) CC7, CC45, and CC30 turned out to be most common. Staphylococcus aureus associated with RT in children showed pathogenicity potential and considerable genetic diversity, and no clones were found to be specific for this condition although further studies are needed.