129 research outputs found
Mupirocin Ointment with and without Chlorhexidine Baths in the Eradication of Staphylococcus Aureus Nasal Carriage in Nursing Home Residents
Mupirocin ointment has been shown to be effective in eradicating Staphylococcus aureus nasal carriage in residents of a long- term care facility. Antiseptic soaps have been used as adjunct to this therapy. We compared the efficacy of short-term intranasal mupirocin ointment with and without chlorhexidine baths in the eradication of S. aureus nasal carriage with follow-up for 12 weeks. METHODS: Residents in four nursing homes known to have endemic methicillin-resistant S. aureus were screened for nasal carriage of S. aureus. Residents who had anterior nares cultures positive for S. aureus on two separate occasions were divided into two groups. Both groups received intranasal mupirocin ointment twice daily for 5 days and one group also received chlorhexidine baths for the first 3 days. Cultures of anterior nares, axilla, and groins were performed before treatment and 1 day and 1, 4, 8, and 12 weeks after treatment. RESULTS: After treatment, S. aureus nasal carriage was eradicated in all residents. Recolonization with S. aureus had occurred at 12 weeks in 24% of residents receiving mupirocin ointment alone (6/25) and in 15% of residents receiving mupirocin ointment plus chlorhexidine baths (4/27). CONCLUSIONS: A short course of mupirocin ointment was effective in eradicating nasal carriage of S. aureus in nursing home residents. There were no statistical differences in efficacy between the two regimens with respect to the eradication of nasal carriage and prevention of recolonization with S. aureus
The efficacy of mupirocin ointment and chlorhexidine body scrubs in the eradication of nasal carriage of Staphylococcus aureus among patients undergoing long-term hemodialysis
Patients undergoing long-term hemodialysis have a high prevalence of Staphylococcus aureus nasal carriage, which may lead to serious infections. Mupirocin ointment has been used intranasally to eradicate S. aureus carriage in health human volunteers and health care workers. Chlorhexidine, an antiseptic with excellent antistaphylococcal activity, is widely used for handwashing and skin cleansing. METHODS: Anterior nares cultures were obtained from patients older than 18 years who were undergoing long-term hemodialysis. Patients with S. aureus nasal carriage were enrolled in the study. Axillae and groins were cultured. Patients were given mupirocin ointment intranasally twice per day for 7 days and chlorhexidine body scrubs daily for the first 3 days. Follow-up cultures were obtained from anterior nares, axillae, and groins at 1 day, and 1, 4, 8 and 12 weeks after treatment. RESULTS: One day after completion of treatment nasal carriage was eradicated in 83% of patients (15/18). After 12 weeks, 69% of patients (11/16) were free of nasal carriage. CONCLUSIONS: Success rates of eradication were excellent compared with those in other published reports. This simple and effective regimen had no major side effect
Cloxacillin versus vancomycin for presumed late-onset sepsis in the Neonatal Intensive Care Unit and the impact upon outcome of coagulase negative staphylococcal bacteremia: a retrospective cohort study
BACKGROUND: Coagulase negative staphylococcus (CONS) is the main cause of late-onset sepsis in Neonatal Intensive Care Units (NICU). Although CONS rarely causes fulminant sepsis, vancomycin is frequently used as empiric therapy. Indiscriminate use of vancomycin has been linked to the emergence of vancomycin resistant organisms. The objective of this study was to compare duration of CONS sepsis and mortality before and after implementation of a policy of selective vancomycin use and compare use of vancomycin between the 2 time periods. METHODS: A retrospective study was conducted of infants ≥4 days old, experiencing signs of sepsis with a first positive blood culture for CONS, during two 12-month periods. Late-onset sepsis was treated empirically with vancomycin and gentamicin during period 1, and cloxacillin and gentamicin during period 2. The confidence interval method was used to assess non-inferiority of the outcomes between the two study groups. RESULTS: There were 45 episodes of CONS sepsis during period 1 and 37 during period 2. Duration of sepsis was similar between periods (hazard ratio of 1.00, 95%CI: 0.64, 1.57). One death during period 2 was possibly related to CONS sepsis versus none in period 1. Vancomycin was used in 97.8% of episodes in period 1 versus 81.1% of episodes in period 2. CONCLUSION: Although we failed to show non-inferiority of duration of sepsis in the cloxacillin and gentamicin group compared to the vancomycin and gentamicin group, duration of sepsis was clinically similar. Restricting vancomycin for confirmed cases of CONS sepsis resistant to oxacillin appears effective and safe, and significantly reduces vancomycin use in the NICU
Impact of Empiric Antimicrobial Therapy on Outcomes in Patients with Escherichia coli and Klebsiella pneumoniae Bacteremia: A Cohort Study
<p>Abstract</p> <p>Background</p> <p>It is unclear whether appropriate empiric antimicrobial therapy improves outcomes in patients with bacteremia due to <it>Escherichia coli </it>or <it>Klebsiella</it>. The objective of this study is to assess the impact of appropriate empiric antimicrobial therapy on in-hospital mortality and post-infection length of stay in patients with <it>Escherichia coli </it>or <it>Klebsiella </it>bacteremia while adjusting for important confounding variables.</p> <p>Methods</p> <p>We performed a retrospective cohort study of adult patients with a positive blood culture for <it>E. coli </it>or <it>Klebsiella </it>between January 1, 2001 and June 8, 2005 and compared in-hospital mortality and post-infection length of stay between subjects who received appropriate and inappropriate empiric antimicrobial therapy. Empiric therapy was defined as the receipt of an antimicrobial agent between 8 hours before and 24 hours after the index blood culture was drawn and was considered appropriate if it included antimicrobials to which the specific isolate displayed <it>in vitro </it>susceptibility. Data were collected electronically and through chart review. Survival analysis was used to statistically assess the association between empiric antimicrobial therapy and outcome (mortality or length of stay). Multivariable Cox proportional hazards models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI).</p> <p>Results</p> <p>Among 416 episodes of bacteremia, 305 (73.3%) patients received appropriate empiric antimicrobial therapy. Seventy-one (17%) patients died before discharge from the hospital. The receipt of appropriate antimicrobial agents was more common in hospital survivors than in those who died (p = 0.04). After controlling for confounding variables, there was no association between the receipt of appropriate empiric antimicrobial therapy and in-hospital mortality (HR, 1.03; 95% CI, 0.60 to 1.78). The median post-infection length of stay was 7 days. The receipt of appropriate antimicrobial agents was not associated with shortened post-infection length of stay, even after controlling for confounding (HR, 1.11; 95% CI 0.86 to 1.44).</p> <p>Conclusion</p> <p>Appropriate empiric antimicrobial therapy for <it>E. coli </it>and <it>Klebsiella </it>bacteremia is not associated with lower in-hospital mortality or shortened post-infection length of stay. This suggests that the choice of empiric antimicrobial agents may not improve outcomes and also provides data to support a randomized trial to test the hypothesis that use (and overuse) of broad-spectrum antibiotics prior to the availability of culture results is not warranted.</p
Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited
BACKGROUND: Invasive infection with Streptococcus pneumoniae (pneumococci) causes significant morbidity and mortality. Case series and experimental data have shown that the capsular serotype is involved in the pathogenesis and a determinant of disease outcome. METHODS: Retrospective review of 464 cases of invasive disease among adults diagnosed between 1990 and 2001. Multivariate Cox proportional hazard analysis. RESULTS: After adjustment for other markers of disease severity, we found that infection with serotype 3 was associated with an increased relative risk (RR) of death of 2.54 (95% confidence interval (CI): 1.22–5.27), whereas infection with serotype 1 was associated with a decreased risk of death (RR 0.23 (95% CI, 0.06–0.97)). Additionally, older age, relative leucopenia and relative hypothermia were independent predictors of mortality. CONCLUSION: Our study shows that capsular serotypes independently influenced the outcome from invasive pneumococcal disease. The limitations of the current polysaccharide pneumococcal vaccine warrant the development of alternative vaccines. We suggest that the virulence of pneumococcal serotypes should be considered in the design of novel vaccines
Clostridia Initiate Heavy Metal Bioremoval in Mixed Sulfidogenic Cultures
Sulfate reducing bacteria (SRB) are widely used for attenuating heavy metal pollution by means of sulfide generation. Due to their low metal tolerance, several SRB species depend on associated bacteria in mixed cultures to cope with metal-induced stress. Yet the identity of the SRB protecting bacteria is largely unknown. We aimed to identify these associated bacteria and their potential role in two highly metal-resistant mixed SRB cultures by comparing bacterial
community composition and SRB activity between these cultures and two sensitive ones. The SRB composition in the resistant and sensitive consortia was similar. However, whereas the SRB in the sensitive cultures were strongly inhibited by a
mixture of copper, zinc, and iron, no influence of these metals was detected on SRB growth and activity in the resistant cultures.
In the latter, a Gram-positive population mostly assigned to Clostridium spp.initiated heavy metal bioremoval based on sulfide
generation from components of the medium (mainly sulfite) but not from sulfate. After metal levels were lowered by the
Clostridium spp. populations, SRB started sulfate reduction and raised the pH of the medium. The combination of sulfite
reducing Clostridium spp. with SRB may improve green technologies for removal of heavy metals
Rhesus Macaques (Macaca mulatta) Are Natural Hosts of Specific Staphylococcus aureus Lineages
Currently, there is no animal model known that mimics natural nasal colonization by Staphylococcus aureus in humans. We investigated whether rhesus macaques are natural nasal carriers of S. aureus. Nasal swabs were taken from 731 macaques. S. aureus isolates were typed by pulsed-field gel electrophoresis (PFGE), spa repeat sequencing and multi-locus sequence typing (MLST), and compared with human strains. Furthermore, the isolates were characterized by several PCRs. Thirty-nine percent of 731 macaques were positive for S. aureus. In general, the macaque S. aureus isolates differed from human strains as they formed separate PFGE clusters, 50% of the isolates were untypeable by agr genotyping, 17 new spa types were identified, which all belonged to new sequence types (STs). Furthermore, 66% of macaque isolates were negative for all superantigen genes. To determine S. aureus nasal colonization, three nasal swabs from 48 duo-housed macaques were taken during a 5 month period. In addition, sera were analyzed for immunoglobulin G and A levels directed against 40 staphylococcal proteins using a bead-based flow cytometry technique. Nineteen percent of the animals were negative for S. aureus, and 17% were three times positive. S. aureus strains were easily exchanged between macaques. The antibody response was less pronounced in macaques compared to humans, and nasal carrier status was not associated with differences in serum anti-staphylococcal antibody levels. In conclusion, rhesus macaques are natural hosts of S. aureus, carrying host-specific lineages. Our data indicate that rhesus macaques are useful as an autologous model for studying S. aureus nasal colonization and infection prevention
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