155 research outputs found
Dissemination of new methicillin-resistant Staphylococcus aureus clones in the community
No full textCopyright © 2002, American Society for Microbiology.Multiple methicillin-resistant Staphylococcus aureus (MRSA) clones carrying type IV staphylococcal cassette chromosome mec were identified in the community-acquired MRSA strains of both the United States and Australia. They multiplied much faster than health-care-associated MRSA and were resistant to fewer non-beta-lactam antibiotics. They seem to have been derived from more diverse S. aureus populations than health-care-associated MRSA strains.Keiko Okuma, Kozue Iwakawa, John D. Turnidge, Warren B. Grubb, Jan M. Bell, Frances G. O'Brien, Geoffrey W. Coombs, John W. Pearman, Fred C. Tenover, Maria Kapi, Chuntima Tiensasitorn, Teruyo Ito, and Keiichi Hiramats
The role for rapid molecular diagnostic tests for infectious diseases in precision medicine
No full textIntroduction: In an era of increasing antimicrobial resistance among both bacterial and fungal pathogens, the ability to identify infectious microorganisms directly in clinical specimens to guide effective antimicrobial therapy early in the course of disease has become paramount. Molecular diagnostic tests that can detect pathogens in multiple specimen types including blood, sputum, stool, urine or cerebrospinal fluid, can decrease the time to diagnosis often to less than 1 hour and improve both antimicrobial use and associated infection prevention measures. Although molecular tests typically demonstrate high degrees of sensitivity and specificity, their cost and the lack of outcome studies showing their positive impact on patient management can be impediments to uptake in laboratories. Areas covered: Diagnostic tests used to identify a broad range of infectious agents causing respiratory tract infections, sexually transmitted infections, sepsis, as well as tests for biomarkers indicative of infection are reviewed. Data are based on a search of the literature using PubMed. Expert commentary: Rapid molecular diagnostic methods are the standard of care for many sexually transmitted diseases and are used increasingly to identify agents of sepsis. Host response markers to identify the presence of infection and differentiate between bacterial and viral agents will be the next major wave of diagnostic tools. Barriers to implementation of molecular diagnostic tests include siloed hospital budgets and the reluctance of many physicians to switch to rapid technologies that, while often superior to traditional microbiological methods in sensitivity and specificity, have little published outcome data to support their use
Using Molecular Diagnostics to Develop Therapeutic Strategies for Carbapenem-Resistant Gram-Negative Infections
No full textInfections caused by multidrug-resistant Gram-negative organisms have become a global threat. Such infections can be very difficult to treat, especially when they are caused by carbapenemase-producing organisms (CPO). Since infections caused by CPO tend to have worse outcomes than non-CPO infections, it is important to identify the type of carbapenemase present in the isolate or at least the Ambler Class (i.e., A, B, or D), to optimize therapy. Many of the newer beta-lactam/beta-lactamase inhibitor combinations are not active against organisms carrying Class B metallo-enzymes, so differentiating organisms with Class A or D carbapenemases from those with Class B enzymes rapidly is critical. Using molecular tests to detect and differentiate carbapenem-resistance genes (CRG) in bacterial isolates provides fast and actionable results, but utilization of these tests globally appears to be low. Detecting CRG directly in positive blood culture bottles or in syndromic panels coupled with bacterial identification are helpful when results are positive, however, even negative results can provide guidance for anti-infective therapy for key organism-drug combinations when linked to local epidemiology. This perspective will focus on the reluctance of laboratories to use molecular tests as aids to developing therapeutic strategies for infections caused by carbapenem-resistant organisms and how to overcome that reluctance
Molecular and Mass Spectrometry Detection and Identification of Causative Agents of Bloodstream Infections
No full textBloodstream infections (BSIs) are severe diseases associated with a high morbidity and mortality, which increases with the delay until administration of the first appropriate antibiotic (1–8). For this reason, empiric treatments made of broad-range anti-infectious compounds or made of a combination of antimicrobials are started immediately after the sampling of blood bottles. BSIs can be caused by various microorganisms. In the absence of microbiological documentation, physicians suspect a BSI on the basis of clinical symptoms, which trigger the start of empirical treatments. The clinical presentations are multiple and include fever or hypothermia, increases in heart rate, change in inflammatory variable (C-reactive protein, procalcitonin, and white blood cell count increase), and organ failure (2, 9). These symptoms are generally nonspecific and only suggest bloodstream dissemination. Empirical treatments are made of broad-spectrum antibiotics on the basis of the clinical and epidemiological data, but this does not exclude any risk of inappropriate initial treatment
Recommendations for Preventing the Spread of Vancomycin Resistance; Recommendations of the Hospital Infection Control Practices Advisory Committee (HICPAC)
No full textSince 1989, a rapid increase in the incidence of infection and colonization with vancomycin-resistant enterococci (VRE) has been reported by U.S. hospitals. This increase poses important problems, including a) the lack of available antimicrobial therapy for VRE infections, because most VRE are also resistant to drugs previously used to treat such infections (e.g., aminoglycosides and ampicillin), and b) the possibility that the vancomycin-resistant genes present in VRE can be transferred to other gram-positive microorganisms (e.g., Staphylococcus aureus). An increased risk for VRE infection and colonization has been associated with previous vancomycin and/or multiantimicrobial therapy, severe underlying disease or immunosuppression, and intraabdominal surgery. Because enterococci can be found in the normal gastrointestinal and female genital tracts, most enterococcal infections have been attributed to endogenous sources within the individual patient. However, recent reports of outbreaks and endemic infections caused by enterococci, including VRE, have indicated that patient-to-patient transmission of the microorganisms can occur either through direct contact or through indirect contact via a) the hands of personnel or b) contaminated patient-care equipment or environmental surfaces. This report presents recommendations of the Hospital Infection Control Practices Advisory Committee for preventing and controlling the spread of vancomycin resistance, with a special focus on VRE. Preventing and controlling the spread of vancomycin resistance will require coordinated, concerted efforts from all involved hospital departments and can be achieved only if each of the following elements is addressed: a) prudent vancomycin use by clinicians, b) education of hospital staff regarding the problem of vancomycin resistance, c) early detection and prompt reporting of vancomycin resistance in enterococci and other gram-positive microorganisms by the hospital microbiology laboratory, and d) immediate implementation of appropriate infection-control measures to prevent person-to-person transmission of VRE.These guidelines were prepared for publication by the following CDC staff: Ofelia C. Tablan, Fred C. Tenover, William J. Martone, Robert P. Gaynes, William R. Jarvis, Martin S. Favero, J. Shaw, Hospital Infections Program, National Center for Infectious Diseases in collaboration with the Subcommittee on Prevention and Control of Antimicrobial-Resistant Microorganisms in Hospitals .Includes bibliographical references (p. 10-13)
Commentary on Blaser\u27s Antibiotic use and its consequences for the normal microbiome
No full textIf you have not read this eye-opening commentary by Dr. Martin Blaser about the negative impact of the widespread use of antibiotics in children, you should. The goal of giving antibiotics to children usually is to treat an infection — an earache, a respiratory tract infection, or perhaps a potentially deadly bloodstream infection. Those antibiotics, however, will often kill more than just the bacteria that are causing the infection. Humans have large quantities of “good bacteria” in our intestinal tracts, on our skin, and elsewhere on our body that play an important role in keeping us healthy
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