Antibiotic prescribing for endodontic infections: a survey of dental students in Italy

Aim To determine the knowledge of final year undergraduate students attending Italian universities on the appropriate use of systemic antibiotics for endodontic infections. Methodology Final year dental students from twenty Italian universities completed a one-page questionnaire on antibiotic use for the treatment of endodontic infections. Data were analysed using descriptive statistics and chi-square tests. Results A total of three hundred and three students completed the questionnaire. The average duration of antibiotic prescription proposed by respondents was 5.48 1.06 days. Amoxicillin with clavulanic acid was the first-choice antibiotic (85.2%) followed by amoxicillin alone (13.5%), azithromycin (1.0%) and clarithromycin (0.3%), for patients not allergic to penicillin. Clarithromycin was the first-choice drug for patients with a penicillin allergy (56.1%), followed from azithromycin (31.7%), clindamycin (11.9%) and levofloxacin (0.3%). Alveolar abscess with systemic manifestations was reported as the principal reason to prescribe antibiotics (97.7%) followed by the same condition without systemic manifestations (85.5%). For the scenario of irreversible pulpitis, 5% of students considered antibiotics necessary. Almost 52% of students would prescribe antibiotics for apical acute periodontitis; 29.7% would prescribe antibiotics for chronic apical periodontitis with sinus tract, and 13.5% indicated these drugs for chronic apical periodontitis without sinus tract. Conclusions The results demonstrate that it is necessary to improve the knowledge of Italian students on antibiotics and indications for their use in endodontics

Rapid generation of human B-cell lymphomas via combined expression of Myc and Bcl2 and their use as a preclinical model for biological therapies

Although numerous mouse models of B-cell malignancy have been developed via the enforced expression of defined oncogenic lesions, the feasibility of generating lineage-defined human B-cell malignancies using mice reconstituted with modified human hematopoietic stem cells (HSCs) remains unclear. In fact, whether human cells can be transformed as readily as murine cells by simple oncogene combinations is a subject of considerable debate. Here, we describe the development of humanized mouse model of MYC/BCL2-driven ‘double-hit’ lymphoma. By engrafting human HSCs transduced with the oncogene combination into immunodeficient mice, we generate a fatal B malignancy with complete penetrance. This humanized-MYC/BCL2-model (hMB) accurately recapitulates the histopathological and clinical aspects of steroid-, chemotherapy- and rituximab-resistant human ‘double-hit’ lymphomas that involve the MYC and BCL2 loci. Notably, this model can serve as a platform for the evaluation of antibody-based therapeutics. As a proof of principle, we used this model to show that the anti-CD52 antibody alemtuzumab effectively eliminates lymphoma cells from the spleen, liver and peripheral blood, but not from the brain. The hMB humanized mouse model underscores the synergy of MYC and BCL2 in ‘double-hit’ lymphomas in human patients. Additionally, our findings highlight the utility of humanized mouse models in interrogating therapeutic approaches, particularly human-specific monoclonal antibodies.Kathy and Curt Marble Cancer Research FundSingapore-MIT Alliance for Research and TechnologyNational Institutes of Health (U.S.) (Grant R01-CA128803)Virginia and Daniel K. Ludwig Graduate FellowshipNational Institute of General Medical Sciences (U.S.) (Medical Scientist Training Program Grant T32GM007753)MIT School of Science (Cancer Research Fellowship

Antibiotic prophylaxis for endocarditis: time to reconsider

The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Some cardiac conditions require antibiotic prophylaxis for some types of dental treatment to reduce the risk of infective endocarditis (IE). All medical and dental practitioners are familiar with this practice but tend to use different regimens in apparently similar circumstances. Generally, the trend has been to prescribe antibiotics if in doubt. This review explores the evidence for antibiotic prophylaxis to prevent IE: does it work and is it safe? The changing nature of IE, the role of bacteraemia of oral origin and the safety of antibiotics are also reviewed. Most developed countries have national guidelines and their points of similarity and difference are discussed. One can only agree with the authority who describes antibiotic guidelines for endocarditis as being ‘like the Dead Sea Scrolls, they are fragmentary, imperfect, capable of various interpretations and (mainly) missing!’ Clinical case-controlled studies show that the more widely antibiotics are used, the greater the risk of adverse reactions exceeding the risk of IE. However, the consensus is that antibiotic prophylaxis is mandatory for a small number of high-risk cardiac and high-risk dental procedures. There are a large number of low-risk cardiac and dental procedures in which the risk of adverse reactions to the antibiotics exceeds the risk of IE, where prophylaxis should not be provided. There is an intermediate group of cardiac and dental procedures for which careful individual evaluation should be made to determine whether IE or antibiotics pose the greater risk. These categories are presented. All medical and dental practitioners need to reconsider their approach in light of these current findings.J Singh, I Straznicky, M Avent and AN Gos

Should patients with hip joint prosthesis receive antibiotic prophylaxis before dental treatment?

The safety committee of the American Academy of Orthopedic Surgeons (AAOS) recommended in 2009 that clinicians should consider antibiotic prophylaxis for all patients with total joint replacement before any invasive procedure that may cause bacteremia. This has aroused confusion and anger among dentists asking for the evidence. The present review deals with different aspects of the rationale for this recommendation giving attention to views both in favor of and against it