Colonization of humans with Staphylococcus aureus is a critical prerequisite of subsequent clinical infection of the skin, blood, lung, heart and other deep tissues. S. aureus persistently or ...intermittently colonizes the nares of approximately 50% of healthy adults, whereas approximately 50% of the general population is rarely or never colonized by this pathogen. Because microbial consortia within the nasal cavity may be an important determinant of S. aureus colonization we determined the composition and dynamics of the nasal microbiota and correlated specific microorganisms with S. aureus colonization.
Nasal specimens were collected longitudinally from five healthy adults and a cross-section of hospitalized patients (26 S. aureus carriers and 16 non-carriers). Culture-independent analysis of 16S rRNA sequences revealed that the nasal microbiota of healthy subjects consists primarily of members of the phylum Actinobacteria (e.g., Propionibacterium spp. and Corynebacterium spp.), with proportionally less representation of other phyla, including Firmicutes (e.g., Staphylococcus spp.) and Proteobacteria (e.g. Enterobacter spp). In contrast, inpatient nasal microbiotas were enriched in S. aureus or Staphylococcus epidermidis and diminished in several actinobacterial groups, most notably Propionibacterium acnes. Moreover, within the inpatient population S. aureus colonization was negatively correlated with the abundances of several microbial groups, including S. epidermidis (p = 0.004).
The nares environment is colonized by a temporally stable microbiota that is distinct from other regions of the integument. Negative association between S. aureus, S. epidermidis, and other groups suggests microbial competition during colonization of the nares, a finding that could be exploited to limit S. aureus colonization.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A novel coronavirus (MERS-CoV) is causing severe disease in the Middle East. In this report on a hospital outbreak of MERS-CoV infection, 23 confirmed cases and evidence of person-to-person ...transmission were identified. The median incubation period was 5.2 days.
Respiratory viruses are an emerging threat to global health security and have led to worldwide epidemics with substantial morbidity, mortality, and economic consequences. Since the severe acute respiratory syndrome (SARS) pandemic in 2003–2004,
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two additional human coronaviruses — HKU-1 and NL-63 — have been identified, both of which cause mild respiratory infection and are distributed worldwide.
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In September 2012, the World Health Organization (WHO) reported two cases of severe community-acquired pneumonia caused by a novel human β-coronavirus, subsequently named the Middle East respiratory syndrome coronavirus (MERS-CoV).
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Since then, MERS-CoV has been identified as the cause of pneumonia . . .
Azithromycin for Prevention of Exacerbations of COPD Albert, Richard K; Connett, John; Bailey, William C ...
New England journal of medicine/The New England journal of medicine,
08/2011, Letnik:
365, Številka:
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Journal Article
Recenzirano
Odprti dostop
Exacerbations of chronic obstructive pulmonary disease (COPD) are a source of substantial morbidity. In this randomized, controlled trial involving patients with moderately severe COPD, daily ...treatment with azithromycin for 1 year was associated with fewer exacerbations.
Acute exacerbations of chronic obstructive pulmonary disease (COPD) result in frequent visits to physicians' offices and emergency rooms and numerous hospitalizations and days lost from work; they also account for a substantial percentage of the cost of treating COPD.
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Patients who have acute exacerbations of COPD, as compared with patients with COPD who do not have acute exacerbations, have an increased risk of death, a more rapid decline in lung function, and reduced quality of life.
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Although inhaled glucocorticoids, long-acting beta
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-agonists, and long-acting muscarinic antagonists reduce the frequency of acute exacerbations of COPD,
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patients receiving . . .
Clinical immunity to P. falciparum malaria is non‐sterilizing, with adults often experiencing asymptomatic infection. Historically, asymptomatic malaria has been viewed as beneficial and required to ...help maintain clinical immunity. Emerging views suggest that these infections are detrimental and constitute a parasite reservoir that perpetuates transmission. To define the impact of asymptomatic malaria, we pursued a systems approach integrating antibody responses, mass cytometry, and transcriptional profiling of individuals experiencing symptomatic and asymptomatic P. falciparum infection. Defined populations of classical and atypical memory B cells and a TH2 cell bias were associated with reduced risk of clinical malaria. Despite these protective responses, asymptomatic malaria featured an immunosuppressive transcriptional signature with upregulation of pathways involved in the inhibition of T‐cell function, and CTLA‐4 as a predicted regulator in these processes. As proof of concept, we demonstrated a role for CTLA‐4 in the development of asymptomatic parasitemia in infection models. The results suggest that asymptomatic malaria is not innocuous and might not support the induction of immune processes to fully control parasitemia or efficiently respond to malaria vaccines.
Synopsis
Asymptomatic Plasmodium falciparum malaria infection supports protective humoral responses, but it also features an immunosuppressive transcriptional signature with upregulation of pathways involved in the inhibition of T‐cell function.
Asymptomatic malaria is thought to be beneficial for maintaining clinical immunity and remains untreated.
Despite supporting protective humoral immune responses, asymptomatic malaria infections feature an immunosuppressive blood transcriptional signature with upregulation of pathways involved in the control of T‐cell function.
These results suggest that asymptomatic malaria is not innocuous and might not support immune processes to fully control parasitemia or efficiently respond to malaria vaccines.
Asymptomatic Plasmodium falciparum malaria infection supports protective humoral responses, but it also features an immunosuppressive transcriptional signature with upregulation of pathways involved in the inhibition of T‐cell function.
Background. Although complicated skin and soft-tissue infections (SSTIs) are among the most common infections requiring hospitalization, their clinical spectrum, management, and outcomes have not ...been well described. Methods. We report a cohort of consecutive adult patients hospitalized for SSTI from 1 January through 31 December 2007 at an academic medical center. Cases meeting inclusion criteria were reviewed and classified as cellulitis, cutaneous abscess, or SSTI with additional complicating factors. Results. In total, 322 patients were included; 66 (20%) had cellulitis, 103 (32%) had cutaneous abscess, and 153 (48%) had SSTI with additional complicating factors. Injection drug use, diabetes mellitus, and alcohol abuse were common comorbidities. Serum inflammatory markers were routinely measured and blood cultures and imaging studies were routinely performed in each group. Of 150 patients with a positive culture result for an abscess, deep tissue, or blood, Staphylococcus aureus or streptococci were identified in 145 (97%). Use of antibiotics with broad aerobic gram-negative activity (61%–80% of patients) or anaerobic activity (73%–83% of patients) was frequent in each group. The median duration of therapy for cellulitis, cutaneous abscess, and SSTI with additional complicating factors was 13 (interquartile range IQR, 10–14), 13 (IQR, 10–16), and 14 (IQR, 11–17) days, respectively. Treatment failure, recurrence, or rehospitalization due to SSTI within 30 days occurred in 12.1%, 4.9%, and 9.2% of patients, respectively. Conclusions. Hospitalizations for SSTI were common; more than half were due to cellulitis or cutaneous abscess. Frequent use of potentially unnecessary diagnostic studies, broad-spectrum antibiotic therapy, and prolonged treatment courses in these patients suggest targets for antimicrobial stewardship programs.
Staphylococcus aureus remains a leading, virulent pathogen capable of expressing complex drug resistance that requires up to 2–4days for laboratory analysis. In this study, we evaluate the ability of ...automated microscopy of immobilized live bacterial cells to differentiate susceptible from non-susceptible responses of S. aureus isolates (MRSA/MSSA, clindamycin resistance/susceptibility and VSSA/hVISA/VISA) to an antibiotic based on the characterization of as few as 10 growing clones after 4h of growth, compared to overnight growth required for traditional culture based methods. Isolates included 131 characterized CDC isolates, 3 clinical isolates and reference strains. MRSA phenotype testing used 1h of 1μg/mL cefoxitin induction followed by 3h of 6μg/mL cefoxitin. Clindamycin susceptibility testing used 1h of induction by 0.1μg/mL erythromycin followed by 3h of 0.5μg/mL clindamycin. An automated microscopy system acquired time-lapse dark-field images, and then computed growth data for individual immobilized progenitor cells and their progeny clones while exposed to different test conditions. Results were compared to concurrent cefoxitin disk diffusion and D-test references. For CDC organisms, microscopy detected 77/77 MRSA phenotypes and 54/54 MSSA phenotypes, plus 53/56 clindamycin-resistant and 75/75 clindamycin susceptible strains. Automated microscopy was used to characterize heterogeneous and inducible resistance, and perform population analysis profiles. Microscopy-based hVISA population analysis profiles (PAPs) were included as an extended proof of concept, and successfully differentiated VSSA from hVISA and VISA phenotypes compared to plate-based PAP.
•Automated microscopy analyzes growth of immobilized bacterial cells.•It can differentiate susceptible from non-susceptible phenotypes after 4h growth.•Heterogeneous and inducible resistance mechanisms were characterized in 4h.•MRSA phenotype, clindamycin resistance and hVISA were detected.•MRSA phenotype and clindamycin resistance detection required as few as 10 cells.
Dental Disease and Periprosthetic Joint Infection Young, Heather; Hirsh, Joel; Hammerberg, E Mark ...
Journal of bone and joint surgery. American volume,
2014-January-15, 2014-Jan-15, 2014-1-15, 20140115, Letnik:
96, Številka:
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Journal Article
Recenzirano
➤ The number of patients with end-stage osteoarthritis is increasing, and treatment with hip and knee arthroplasty is expected to increase over the next several decades.➤ Dental disease has long been ...anecdotally associated with increased periprosthetic joint infections, although case-control studies do not support this relationship.➤ While most recent guidelines for the prevention of endocarditis have favored treatment of fewer patients, the most recent recommendations for prevention of periprosthetic joint infection have increased the number of patients who would receive antibiotics before a dental procedure.➤ Antibiotics given before a dental procedure decrease the risk of bacteremia from the oral cavity, but this is of uncertain clinical importance.➤ The number of patients who would require antibiotics before dental procedures to prevent one periprosthetic joint infection greatly outnumbers the number of patients who would experience an adverse event associated with antibiotics given before a dental procedure.
IMPORTANCE Antibiotic-resistant bacteria are associated with increased patient morbidity and mortality. It is unknown whether wearing gloves and gowns for all patient contact in the intensive care ...unit (ICU) decreases acquisition of antibiotic-resistant bacteria. OBJECTIVE To assess whether wearing gloves and gowns for all patient contact in the ICU decreases acquisition of methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) compared with usual care. DESIGN, SETTING, AND PARTICIPANTS Cluster-randomized trial in 20 medical and surgical ICUs in 20 US hospitals from January 4, 2012, to October 4, 2012. INTERVENTIONS In the intervention ICUs, all health care workers were required to wear gloves and gowns for all patient contact and when entering any patient room. MAIN OUTCOMES AND MEASURES The primary outcome was acquisition of MRSA or VRE based on surveillance cultures collected on admission and discharge from the ICU. Secondary outcomes included individual VRE acquisition, MRSA acquisition, frequency of health care worker visits, hand hygiene compliance, health care–associated infections, and adverse events. RESULTS From the 26 180 patients included, 92 241 swabs were collected for the primary outcome. Intervention ICUs had a decrease in the primary outcome of MRSA or VRE from 21.35 acquisitions per 1000 patient-days (95% CI, 17.57 to 25.94) in the baseline period to 16.91 acquisitions per 1000 patient-days (95% CI, 14.09 to 20.28) in the study period, whereas control ICUs had a decrease in MRSA or VRE from 19.02 acquisitions per 1000 patient-days (95% CI, 14.20 to 25.49) in the baseline period to 16.29 acquisitions per 1000 patient-days (95% CI, 13.48 to 19.68) in the study period, a difference in changes that was not statistically significant (difference, −1.71 acquisitions per 1000 person-days, 95% CI, −6.15 to 2.73; P = .57). For key secondary outcomes, there was no difference in VRE acquisition with the intervention (difference, 0.89 acquisitions per 1000 person-days; 95% CI, −4.27 to 6.04, P = .70), whereas for MRSA, there were fewer acquisitions with the intervention (difference, −2.98 acquisitions per 1000 person-days; 95% CI, −5.58 to −0.38; P = .046). Universal glove and gown use also decreased health care worker room entry (4.28 vs 5.24 entries per hour, difference, −0.96; 95% CI, −1.71 to −0.21, P = .02), increased room-exit hand hygiene compliance (78.3% vs 62.9%, difference, 15.4%; 95% CI, 8.99% to 21.8%; P = .02) and had no statistically significant effect on rates of adverse events (58.7 events per 1000 patient days vs 74.4 events per 1000 patient days; difference, −15.7; 95% CI, −40.7 to 9.2, P = .24). CONCLUSIONS AND RELEVANCE The use of gloves and gowns for all patient contact compared with usual care among patients in medical and surgical ICUs did not result in a difference in the primary outcome of acquisition of MRSA or VRE. Although there was a lower risk of MRSA acquisition alone and no difference in adverse events, these secondary outcomes require replication before reaching definitive conclusions. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT0131821
Background. Staphylococcus aureus bacteremia causes considerable morbidity and mortality, and strategies to improve management and outcomes of this disease are needed. Methods. Routine consultation ...with an infectious diseases specialist for cases of S. aureus bacteremia was mandated at our institution in May 2005. We compared the evaluation, management, and outcomes of cases before and after this policy change. All comparisons are by period (i.e., before or after initiation of the policy of routine consultation). Results. In the year before and the year after after the implementation of routine consultation, 134 and 100 cases of S. aureus bacteremia, respectively, were evaluated. Consultation rates increased from 53% of cases before to 90% of cases after the policy change (Pt;.001). Echocardiography (57% vs. 73%; P=.01) and radiographic studies (81% vs. 91%; P=.04) were used more frequently during the period of routine consultation, and infective endocarditis or metastatic infections were diagnosed more frequently (33% vs. 46%; P=.04). All 4 standards of care (removal of intravascular foci of infection, obtaining follow-up blood culture samples, use of parenteral β-lactam therapy when possible, and administration of es;28 days of therapy for complicated infections) were adhered to more frequently with routine consultation (40% vs. 74%; Pt;.001). Treatment failure (microbiological failure, recurrent bacteremia, late metastatic infection, or death) occurred less often during the intervention year (17% vs. 12%), but this difference was not statistically significant (P=.27). Conclusions. A policy of routine consultation with an infectious diseases specialist for patients with S. aureus bacteremia resulted in more-detailed evaluation, more-frequent detection of endocarditis and metastatic infection, and improved adherence to standards of care.
Diagnosis of ventilator-associated pneumonia (VAP) is imprecise.
To (1) determine whether alternate-day surveillance mini-bronchoalveolar lavage (mini-BAL) in ventilated adults could reduce time to ...initiation of targeted treatment and (2) evaluate the potential for automated microscopy to reduce analysis time.
Adult intensive care unit patients who were anticipated to require ventilation for at least a further 48 hours were included. Mini-BALs were processed for identification, quantitation, and antibiotic susceptibility, using (1) clinical culture (50 ± 7 h) and (2) automated microscopy (∼5 h plus offline analysis).
Seventy-seven mini-BALs were performed in 33 patients. One patient (3%) was clinically diagnosed with VAP. Of 73 paired samples, culture identified 7 containing pneumonia panel bacteria (>10(4) colony-forming units/ml) from five patients (15%) (4 Staphylococcus aureus 3 methicillin-resistant S. aureus, 2 Stenotrophomonas maltophilia, 1 Klebsiella pneumoniae) and resulted in antimicrobial changes/additions to two of five (40%) of those patients. Microscopy identified 7 of 7 microbiologically positive organisms and 64 of 66 negative samples compared with culture. Antimicrobial responses were concordant in four of five comparisons. Antimicrobial changes/additions would have occurred in three of seven microscopy-positive patients (43%) had those results been clinically available in 5 hours, including one patient diagnosed later with VAP despite negative mini-BAL cultures.
Microbiological surveillance detected infection in patients at risk for VAP independent of clinical signs, resulting in changes to antimicrobial therapy. Automated microscopy was 100% sensitive and 97% specific for high-risk pneumonia organisms compared with clinical culturing. Rapid microscopy-based surveillance may be informative for treatment and antimicrobial stewardship in patients at risk for VAP.
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